Subject: Explosion at Colima volcano
A strong explosion occurred yesterday (29 July 99) at 14:42 hrs (local time) at Colima volcano's crater. Mr. Jesus Mendez, who is the political
authority of La Yerbabuena village (8 km from the crater, ~195 inhabitants, the nearest community) informed via radio that the explosion
was clearly heard and seen from the village. He also estimated that the pyroclastic flows and rockfalls triggered by the explosion reached
approximately the same distances of those produced by the 17 July 1999 explosion: a maximum runout of 5- 5.5 km along La Lumbre gully (volcano's west flank). On the Cordoban barrancas (SW flank) the distal reachness of the pyroclastic flows was estimated by him in ~3-3.5 km from the crater. Following yerterday's explosion, a relatively intense ashfall occurred on La Yerbabuena, causing irritations on eyes among some villagers and visitors, but fortunatelly few minutes after the ashfall, volunteers of Pro
eccion Civil Colima (Cuauhtemoc County) arrived to the village to provide light surgery masks to the people, so the effects of the ashfall were substancially minimized. Before this explosion, policemen of Policia de Procuracion de Justicia de Colima who were at La Yerbabuena previously and during the explosion reported intense jet sounds at 12:40 and some rockfalls.
A very light ashfall was noticed at the city of Colima (32 km to the South of the crater), which started at 17:05 hrs and stopped at ~ 20:00 hrs. More intense ashfall was registered at some towns located on the S and SE sectors of the volcano (Queseria, 7,700 inhabitants, 14.5 km from the crater; Montitlan, more that 50 inhabitants, 12.2 km from the crater).
At 18:04 hrs a strong exhalation was ejected from the crater. The ash column, rose rapidly, and reached at least 5,500 m.a.s.l., which was
clearly seen from the city of Colima. The observers of Proteccion Civil Jalisco posted at their observatory (4,000 m.a.s.l.) on the W upper slopes of Nevado de Colima (5.7 km to the north of Colima volcano's crater) reported that they did not hear any explosion sound accompanying this exhalation. It looks that this exhalation was responsible of most ashfall registered yesterday at the city of Colima.
Juan Carlos Gavilanes Ruiz.
Observatorio Vulcanologico de la Universidad de Colima.
Coordinador del Grupo de Informacion a la Poblacion en Zonas de Alto y
Medino Riesgo.
Topic 2 of 99 [Geo]: Vulcanism
Response 51 of 997: Marcia (MarciaH) * Tue, Aug 3, 1999 (23:48) * 47 lines
Volcano Updates
Date: Mon, 02 Aug 1999 11:55:47 -0700
Subject: Taal News
Increased geothermal activity at Taal volcano in the Philippines continues
with prolonged geysering and volcanic earthquakes. This activity may be due
to heavy rains interacting with subterranean heat.
Full article at: Philippine Headline News
http://www.newsflash.org (see Hometown & Community News)
According to the news article at the above web site, the was a mud
geysering event
on August 1 at Taal that lasted 9 hours, accompanied by 3 volcanic
earthquakes and some steam eruption. Phivolcs has maintained a Level 1 alert at Taal volcano, and has banned visits to the main crater area.
Other information on Taal activity, as well as some recent explosions at
Pinatubo, can be found at the Manila Bulletin website:
http://www.mb.com.ph/main/9907/29jm01g.asp
___________________________________________________________________
Colima, Mexico
*******************************************
Date: Mon, 02 Aug 1999 11:55:47 -0700
Subject: 30 July 1999 Colima Update
The 30 July Press Release indicates that Colima continues to experience
high seismic levels accompanied by periodic moderate explosions or
degassing events, following the major eruption of 29 July.
Loosely translated from: http://www.ucol.mx/volcan/jul30.html
----------------------
Date: Fri, 30 Jul 1999 15:54:08 -0500 (CDT)
Subject: Impact of 29 July Colima explosion
Due to the ashfall caused by the 29 July 14:42 hrs. explosion and
18:04 hrs. exhalation of Colima volcano, aerial traffic at the national
airport of the City of Colima was interrupted from the afternoon of 29 July
until at least 13:00 hrs. on 30 July. Meanwhile, aerial arrivals were
redirected
to the city of Guadalajara (~180 km to the north of Colima city).
Observatorio Vulcanologico de la Universidad de Colima.
Coordinador del Grupo de Informacion a la Poblacion en Zonas de Alto y
Medino Riesgo.
*******************************************
Fuego, Guatemala
*******************************************
Date: Mon, 02 Aug 1999 11:55:47 -0700
Subject: Fuego Update
Fuego remains restless seismically. A periodic hot spot shows up on
satellite imagery and there may be some occasional small ash events. This
is from several reports at: http://www.ssd.noaa.gov/SSD/ML/vaacmsgs.html
Topic 2 of 99 [Geo]: Vulcanism
Response 52 of 997: Marcia (MarciaH) * Fri, Aug 27, 1999 (22:02) * 33 lines
************************************
Guagua Pichincha, Ecuador
************************************
Small phreatic eruption at Guagua Pichincha at 2109 on 16 August, followed
by one hour of tremor. The eruptions on 10 & 12 August have left a thin
veneer of ash on vegetation to the W of the dome. The most recent eruptions
have occurred from the W part of the dome itself. The Cristal River has
become muddy from recent ashfalls.
Photo of Guagua Pichincha showing active features at:
http://www.cybw.net/volcan/fotos/990720d.html
--------------------
On 23 August a small phreatic eruption took place at Guagua Pichincha, not
followed by tremor. At 0807 on 24 a large explosion took place, with a
mushroom-shaped eruption cloud rising to 6km a.s.l and ashfalls to the S.
Two smaller events followed, with an eruption plume to 3km. These events
were followed by tremor. Strong fumarolic activity in the 1981 crater and
the July 1999 craters on the W part of the dome was noted afterwards.
From: http://www.cybw.net/volcan/
************************************
Telica, Nicaragua
************************************
New eruption at Nicaragua's Telica volcano on 10 August, with ash clouds
ascending to 300-400 m above the volcano. This event was somewhat larger
than that of June.
From: www.igc.org
Topic 2 of 99 [Geo]: Vulcanism
Response 53 of 997: Marcia (MarciaH) * Mon, Sep 13, 1999 (13:58) * 0 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 54 of 997: Marcia (MarciaH) * Tue, Sep 14, 1999 (12:38) * 72 lines
U.S. Geological Survey
Hawaiian Volcano Observatory
2:00 p.m. - September 12, 1999
Earthquake swarm and ground deformation event at Kilauea Volcano
Starting about 1:31 Sunday morning, September 12, a swarm of small
earthquakes and associated volcanic tremor began at Kilauea Volcano. The
swarm was concentrated along the east rift zone between Devil's Throat and
Mauna Ulu, but earthquakes eventually occurred in a broader area involving
the summit and south flank areas. The strongest part of the swarm lasted a
couple of hours, but earthquakes are continuing at the time of writing
(2:00 p.m., September 12), as is tremor from the summit caldera. Many of
the earthquakes were felt by residents of Mauna Loa Estates, Volcano, and
other nearby areas. Most of the earthquakes were shallow, within 2-3 miles
of the ground surface. The largest rift zone earthquake was approximately
magnitude 3.0. At 5:59 a.m. the largest earthquake in this episode
occurred beneath Kilauea's south flank, near Pu`u `O`o. This earthquake
was approximately magnitude 3.7, but final calculations have not yet been
made.
Accompanying the earthquake swarm was deflation of the summit area
and the east rift zone between the summit and Pu`u `O`o. The deflation,
detected by five electronic tiltmeters newly installed in this area, began
at about the same time as the earthquakes and tremor. We anticipate that
GPS data, currently being processed, will show substantial widening of the
rift zone.
The floor of crater in Pu`u `O`o collapsed and is now mostly
overed with rubble. Aerial views at about 11 a.m. showed only a tiny pad
of weakly spattering lava remaining in the crater.
The flow of lava through the tube to the coast was weak and
luggish when observed between 11 a.m. and noon. One small trickle was
entering the ocean at the bench, most of which had collapsed into the sea
since about 8 a.m. this morning. By 1:30 p.m., the steam plume had died,
and the eruption had entered into another pause, which likely will last
from a few days to several weeks.
------From the HVO Eruption Update Web Page today:
700 September 13, 1999.
The swarm of earthquakes reported in yesterday's update
(see below) has ended. Summit tilt is slowly recovering, but
ermanent tilt may have been induced at several other
stations. There is no significant tremor at Pu`u `O`o, and the
pause in the eruption continues.
1500 September 12, 1999.
swarm of small earthquakes and associated volcanic tremor
egan at Kilauea at 0131 September 12. The swarm was
oncentrated in a short segment of the upper east rift zone
between Devil's Throat and Mauna Ulu but eventually spread
across the summit and south flank. The main swarm lasted a
couple of hours, but earthquakes continued until at least
1500. Most of the earthquakes were shallow (1-5 km) and small
(magnitude less than 3); nonetheless, residents of the
Volcano area felt many earthquakes in the early Sunday hours.
One magnitude 3.7 earthquake at 0559 took place near Pu`u
`O`o at about 10 km depth. Sharp deflation of the summit and
east rift zone began at the time of the swarm. The rift zone
between the summit and Pu`u `O`o sagged and presumably spread
as magma intruded into the rift zone from beneath the
summit. The floor of the crater in Pu`u `O`o collapsed
several tens of meters and is now strewn with rubble, with
only a tiny pad of weakly spattering lava remaining. These
events initiated a pause in eruptive activity. By 1330 the
steam plume at the ocean entry had died. The bench began to
collapse between about 0800 and 0915 and was more than 80
percent gone by noon. By analogy to episode 54 in January
1997, today's events may initiate a pause that lasts several
days or more.
Topic 2 of 99 [Geo]: Vulcanism
Response 55 of 997: Marcia (MarciaH) * Wed, Sep 15, 1999 (19:43) * 29 lines
Kilauea Volcano Eruption Update
http://wwwhvo.wr.usgs.gov/
Another pause in episode 55 of the Pu`u `O`o - Kupaianaha eruption began at 0131 HST on the
morning of September 12. The supply of magma to Pu`u `O`o was interrupted in response to an
intrusion into the upper east rift zone in an area between Pauahi Crater and Mauna Ulu, based
on the location of small earthquakes and the pattern of ground tilt from several tiltmeters. About
8 hours after the start of the intrusion, the active lava bench on the south coast of Kilauea began
collapsing into the sea. Several small collapses were observed by scientists on September 12,
and by the evening of September 13, about 2 ha (5 acres) had been removed. The discharge of
lava into the sea stopped completely in the afternoon of September 13.
The intrusion began when three tiltmeters at the summit showed a downward tilt of the ground
(red line) toward the caldera. A swarm of small earthquakes along the upper rift zone
accompanied the ground deformation. The downward tilt indicates that magma was moving out
of the summit reservoir; data from two other tiltmeters on the east rift zone (east of Pauahi
Crater and just uprift from Pu`u `O`o) indicate the magma was moving into the rift zone. The
reversal of summit tilt about 4-6 hours later indicates when the intrusion stopped and magma
once again moved into the summit reservoir. An inspection on September 12 of the ground
above the intrusion did not reveal new ground cracks, which suggests the magma intusion did
not reach to within 1-2 km of the surface.
Much remains to be learned from this event. Leveling across the zone of intrusion on September
14 showed changes in elevations that provide clear evidence for a dike, but the size and depth
of the dike remain to be calculated. The onset of seismicity and tilting on September 12 was
abrupt and simultaneous to within the one-minute resolution of the tilt data, all along the rift zone
and the summit. This intriguing observation will be the source of considerable interpretative
effort by HVO staff and colleagues.
Topic 2 of 99 [Geo]: Vulcanism
Response 56 of 997: Alexander Schuth (aschuth) * Fri, Sep 24, 1999 (12:19) * 1 lines
There were heavy quakes in Turkey and Greece, and in Taiwan, also. High casualties in Turkey and Taiwan, several dead in Greece.
Topic 2 of 99 [Geo]: Vulcanism
Response 57 of 997: Marcia (MarciaH) * Fri, Sep 24, 1999 (19:34) * 1 lines
Yes, Indeed - check Geo 9 - Seismology
Topic 2 of 99 [Geo]: Vulcanism
Response 58 of 997: Marcia (MarciaH) * Wed, Sep 29, 1999 (13:14) * 0 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 59 of 997: Marcia (MarciaH) * Wed, Sep 29, 1999 (13:17) * 1 lines
It appears that the mid-atlantic ridge separation and the Pacific Ring of Fire are the only two which are defined by volcanic activity...and the Great Rift Valley in Africa...Each of those little white triangles represents a volcano.
Topic 2 of 99 [Geo]: Vulcanism
Response 60 of 997: Gi (patas) * Thu, Sep 30, 1999 (04:34) * 1 lines
Wonderful map, Marcia, I think this is what I was looking for or very near it, I'll save and study it.:-)
Topic 2 of 99 [Geo]: Vulcanism
Response 61 of 997: Marcia (MarciaH) * Thu, Sep 30, 1999 (12:34) * 1 lines
Great! I found it while looking for something entirely different...and I downloaded it to my space on Spring's hard drive - it is definitely a keeper.
Topic 2 of 99 [Geo]: Vulcanism
Response 62 of 997: Marcia (MarciaH) * Thu, Oct 7, 1999 (18:26) * 30 lines
KILAUEA VOLCANO UPDATE
The lava pond in Pu`u `O`o remains active this
afternoon, and lava is oozing from the lava tube
system onto the surface between Pu`u `O`o and the
top of Pulama Pali. Tremor near the vent has increased
since yesterday.
1545 October 5, 1999
Observations yesterday and early this morning found no
active surface flows on Pulama pali or anywhere else in
the flow field. Consequently we are defining the period
from 2200 on October 3 to 0945 on October 5 as a pause.
During this time, tremor virtually ceased near Pu`u `O`o
and Kilauea's summit was showing slight swelling. However,
by 0945 today breakouts of lava were taking place from a
perched lava pond built above the lava tube about halfway
between Pu`u `O`o and the top of Pulama Pali. The pahoehoe
flows from the perched pond were small, but one entered a
kipuka just west of the pond and started fires. The surface
of Pu`u `O`o's lava lake this morning and early afternoon
was about 7 m below the terrace around the lake, which in
turn is about 50 m below the rim of the crater. A thin
crust caps the lake, broken only by three bubbling areas
and by sporadic crustal overturns. Tremor near Pu`u `O`o
is weak but distinctly higher than during the pause. Tilt
at Kilauea's summit is now flat.
Topic 2 of 99 [Geo]: Vulcanism
Response 63 of 997: Marcia (MarciaH) * Thu, Oct 7, 1999 (18:49) * 1 lines
Since this was written (two day ago) there have been more outbreaks reported by the tour pilots - a frequency I monitor with great regularity.
Topic 2 of 99 [Geo]: Vulcanism
Response 64 of 997: Wolf (wolf) * Fri, Oct 8, 1999 (17:36) * 1 lines
the triangles are volcanoes? didn't know we had so many on the west coast!
Topic 2 of 99 [Geo]: Vulcanism
Response 65 of 997: Marcia (MarciaH) * Fri, Oct 8, 1999 (17:52) * 1 lines
All of the Cascades are volcanic from Seattle to Mt Shasta in California...and Lassen!
Topic 2 of 99 [Geo]: Vulcanism
Response 66 of 997: Marcia (MarciaH) * Fri, Oct 8, 1999 (17:55) * 1 lines
The Pilots today are reporting that since the old tube system is blocked by cooling lava, the new flows are coming out of a "sky light" hole in the tube system and is forming a new cinder cone around the vent. Mountain building going on as we speak...almost in my back yard, actually!
Topic 2 of 99 [Geo]: Vulcanism
Response 67 of 997: Wolf (wolf) * Sat, Oct 9, 1999 (15:22) * 1 lines
watching nature recreate herself!
Topic 2 of 99 [Geo]: Vulcanism
Response 68 of 997: Marcia (MarciaH) * Sat, Oct 9, 1999 (16:52) * 1 lines
This is not only true at the vent (making the spatter and cinder cone) but also at the ocean where the island increases its size as flows harden and extend beyond the existing shoreline. From time to time that also becomes unstable and acres of the stuff crash back into the sea - and on occasion has taken a visitor, who ignored the warning signs and ropes, with it. I am a great believer in what the ranger tell us is safe and what is not safe - they are not there to spoil our fun!
Topic 2 of 99 [Geo]: Vulcanism
Response 69 of 997: Wolf (wolf) * Sat, Oct 9, 1999 (20:58) * 1 lines
good for you! cuz we wouldn't want our marcia and volcano lover to be too swept away in the moment!! *hugs*
Topic 2 of 99 [Geo]: Vulcanism
Response 70 of 997: Marcia (MarciaH) * Sat, Oct 9, 1999 (21:12) * 11 lines
*hugs* Thanks!...me too...! Gonna post a few pictures to show the different side of the story of lava - it nourishes as well as kills:
Stop sign in a buried street:
New Land and Black Sand Beach being created:
Little Ohia Tree growing in crack of hardened Pahoehoe Flow:
Topic 2 of 99 [Geo]: Vulcanism
Response 71 of 997: Wolf (wolf) * Sat, Oct 9, 1999 (21:37) * 1 lines
yes, just like natural occuring forest fires. it's done on purpose by mother nature herself!
Topic 2 of 99 [Geo]: Vulcanism
Response 72 of 997: Marcia (MarciaH) * Sat, Oct 9, 1999 (21:44) * 1 lines
Absolutely! Some seeds will not germinate without first having gone through a fire - or through the digestive tract of an animal! Very good point, My Dear!
Topic 2 of 99 [Geo]: Vulcanism
Response 73 of 997: Marcia (MarciaH) * Mon, Oct 11, 1999 (16:40) * 4 lines
VOLCANOES OF THE WEST COAST
Topic 2 of 99 [Geo]: Vulcanism
Response 74 of 997: Wolf (wolf) * Tue, Oct 12, 1999 (19:30) * 1 lines
i had no idea we had that many over there! and here i thought our only volcano in the conus was mt st. helens!!
Topic 2 of 99 [Geo]: Vulcanism
Response 75 of 997: Marcia (MarciaH) * Tue, Oct 12, 1999 (19:51) * 1 lines
...and who says the internet is not educational...?! I hunted for just this sort of map. I think there are many people who think the ones in Hawaii and perhaps Alaska and Mt St Helens are the only volcanoes we have. Not so!!! Ours are just more active at the moment...
Topic 2 of 99 [Geo]: Vulcanism
Response 76 of 997: John Burnett (mrchips) * Tue, Oct 12, 1999 (22:52) * 23 lines
Rock Becomes a River
--by John Burnett, copyright 1999
Rock becomes a river underground,
superheated, supercharged,
answering only to Madame Pele.
Rock becomes a river underground,
spewing forth as a mighty geyser
leaping, reaching ever higher,
seeking to paint the sky
and cover its blue
with a brilliant hue of red.
Rock becomes a river underground,
trickling to the surface, then meandering
at a nearly apologetic pace
while coursing an interminable, inevitable,
inescapable path,
altering both topographic and human landscapes,
playing no favorites--
and exploding in a toxic haze
where the river meets the sea.
Topic 2 of 99 [Geo]: Vulcanism
Response 77 of 997: Marcia (MarciaH) * Tue, Oct 12, 1999 (23:02) * 1 lines
This is magnificent, John. I am honored you chose to put it here! It is wonderful beyond words and Geo is privileged to have been so chosen. Mahalo Nui Loa.
Topic 2 of 99 [Geo]: Vulcanism
Response 78 of 997: John Burnett (mrchips) * Tue, Oct 12, 1999 (23:06) * 1 lines
It is unpublished, so Geo is first. Thank you.
Topic 2 of 99 [Geo]: Vulcanism
Response 79 of 997: Marcia (MarciaH) * Tue, Oct 12, 1999 (23:10) * 1 lines
(bowing with appreciation and humility)...*speechless but glowing* *HUG*
Topic 2 of 99 [Geo]: Vulcanism
Response 80 of 997: Marcia (MarciaH) * Tue, Oct 12, 1999 (23:42) * 5 lines
In tribute to your inspired poem, I offer the generation of that creative power
Pu'u O'o in Eruption
Topic 2 of 99 [Geo]: Vulcanism
Response 81 of 997: John Burnett (mrchips) * Wed, Oct 13, 1999 (00:26) * 1 lines
Pu`u Oh! Oh!
Topic 2 of 99 [Geo]: Vulcanism
Response 82 of 997: Marcia (MarciaH) * Wed, Oct 13, 1999 (00:33) * 1 lines
*laugh* You're delightful...!
Topic 2 of 99 [Geo]: Vulcanism
Response 83 of 997: John Burnett (mrchips) * Wed, Oct 13, 1999 (02:21) * 1 lines
In the immortal words of my late daddy, E: "Thankya verramuch!"
Topic 2 of 99 [Geo]: Vulcanism
Response 84 of 997: Gi (patas) * Thu, Oct 14, 1999 (14:00) * 5 lines
Both of you make this a very nice place to be. Thanks :-)
BTW, learned a new Internet symbol
[]
means "hug"
so please consider yourselves hugged :-)
Topic 2 of 99 [Geo]: Vulcanism
Response 85 of 997: Marcia (MarciaH) * Thu, Oct 14, 1999 (14:37) * 1 lines
Ah...Thank you! I did not know about that! All the ones I have in Arial are more square than that. Where did you find it? (other than in character map)
Topic 2 of 99 [Geo]: Vulcanism
Response 86 of 997: Marcia (MarciaH) * Thu, Oct 14, 1999 (14:40) * 1 lines
trying....
Topic 2 of 99 [Geo]: Vulcanism
Response 87 of 997: Karen (KarenR) * Mon, Oct 18, 1999 (23:41) * 1 lines
Where are the pictures of Mt. Etna? A whole lotta lava flowing...
Topic 2 of 99 [Geo]: Vulcanism
Response 88 of 997: Marcia (MarciaH) * Mon, Oct 18, 1999 (23:51) * 0 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 89 of 997: Marcia (MarciaH) * Mon, Oct 18, 1999 (23:53) * 1 lines
Nothing is showing on my life cam on the wx program. If this does not update I will scribble it and post static pictures of that eruption
Topic 2 of 99 [Geo]: Vulcanism
Response 90 of 997: Marcia (MarciaH) * Mon, Oct 18, 1999 (23:57) * 1 lines
Will post the photo captures from Mt Etna when I get them - the live cam did not update in here.
Topic 2 of 99 [Geo]: Vulcanism
Response 91 of 997: John Burnett (mrchips) * Mon, Oct 18, 1999 (23:57) * 1 lines
The new thematic buttons are nice, but the "forget" button forgot to download.
Topic 2 of 99 [Geo]: Vulcanism
Response 92 of 997: Marcia (MarciaH) * Tue, Oct 19, 1999 (00:00) * 1 lines
I have searched all over my three identical files Wolfie sent to me with the buttons...it is just not there. Unless one can be tweeked by the master tweeker and installed (I ftp'd extra buttons over to spring) perhaps the tweeker could post some other forget...! Actually, they forgot to send it!
Topic 2 of 99 [Geo]: Vulcanism
Response 93 of 997: Marcia (MarciaH) * Mon, Oct 25, 1999 (21:29) * 20 lines
EPISODIC ACTIVITY AND LAVA OVERFLOWS FROM THE BOCCA
NUOVA OF ETNA CONTINUE. Repeated surges of lava have overflowed
the western rim of the Bocca Nuova, one of Etna's four summit craters,
since late 17 October, and spilled up to 4 km down the western flank of
the volcano. The overflows were caused by episodes of violent Strombolian
activity and lava fountaining at the crater which is completely filled; a
sizeable pyroclastic cone is growing in the western part of the Bocca
Nuova. Bombs are thrown over a large part of the summit area, making
visits to the scene of this exceptional activity highly dangerous. A detailed
report will be posted later today on the Etna News Page. - WORLDWIDE
VOLCANISM UPDATE.
http://www.geo.mtu.edu/~boris/gifs/image/Etna181099_1.jpg
Topic 2 of 99 [Geo]: Vulcanism
Response 94 of 997: Marcia (MarciaH) * Mon, Oct 25, 1999 (21:34) * 13 lines
MT ETNA ERUPTION UPDATE http://www.geo.mtu.edu/~boris/ETNA_news.html
21 October 1999 update. After continuing vigorously until the early morning of 20 October, the
activity from the eruptive vents in the W and NW part of the Bocca Nuova ceased, and the
overflow of lava through the notch (formed on 17 October) in the W crater rim stopped. Sometime
around dawn (0700 h local time=GMT+2), forceful expulsions of ash began from the SE vent in
the Bocca Nuova, which had shown little activity in the past week. Later that day weather
conditions deteriorated, and visual observations were rendered impossible. However, it was
stated this morning that the activity was at low levels throughout the day (communication from
Marco Fulle, Osservatorio Astronomico di Trieste, who presently stays at the Rifugio Sapienza
and received this information from forest guard personnel). This morning at 0300 h, intense
eruptive activity reportedly resumed, with renewed lava overflow from the Bocca Nuova onto the
W flank. As of the early afternoon of 21 October, bad weather is preventing visual observations.
Topic 2 of 99 [Geo]: Vulcanism
Response 95 of 997: Gi (patas) * Tue, Oct 26, 1999 (12:59) * 2 lines
Awesome!
I was in Taormina two years ago, and we could see Mt. Etna in the distance. Very quiet at the time. Wonder what it looks like from out there now...
Topic 2 of 99 [Geo]: Vulcanism
Response 96 of 997: Marcia (MarciaH) * Tue, Oct 26, 1999 (13:04) * 1 lines
The weather has been particularly bad lately which is why their Volcano Cam is not sending images - it seems like fog and low clouds are obscuring the eruption, but a glow is suffused throughout the entire area surrounding the mountain. It will be nice with the weather clears - though eruptions have been known to make their own weather systems. We'll just have to wait...I promise to post something as soon as it is available.
Topic 2 of 99 [Geo]: Vulcanism
Response 97 of 997: Marcia (MarciaH) * Mon, Nov 1, 1999 (20:35) * 13 lines
Interesting Volcano Trivia http://www.dc.peachnet.edu/~pgore/students/f96/students/harris/webpage.htm
The Tambora Volcano, located in Indonesia, killed 92,000 people in 1815- the
most people ever killed by a volcano.
There are, at best guess, 1511 volcanoes that have erupted in the last 10,000 years.
The biggest volcano is the world is Mauna Loa in Hawaii (80,000 cubic kilometers).
The biggest volcano in our solar system is Olympus Mons on Mars (17 miles tall).
Ojos del Salado in Chile is the world's tallest volcano (22,589 ft or 6887m).
The largest eruption ever was Yellowstone 2.2 million years ago. The eruption
produced 2500 cubic kilometers of ash.
The youngest volcano is Paricutin in Mexico. It grew out of a cornfield in 1943 and erupted for 8-9 years.
Diamonds cannot be melted by lava.
Topic 2 of 99 [Geo]: Vulcanism
Response 98 of 997: Marcia (MarciaH) * Mon, Nov 1, 1999 (20:42) * 1 lines
Surtsey in Iceland is younger than Paricutin...And from Base to summit, Mauna Loa is the world's tallest volcano - 28,000' (8534.4 M) below sea level + almost 14,000' (4267 M) above sea level makes it 42,000' (12602 M) total.
Topic 2 of 99 [Geo]: Vulcanism
Response 99 of 997: Gi (patas) * Wed, Nov 3, 1999 (13:57) * 2 lines
(Marcia)Diamonds cannot be melted by lava.
So they are still a girl's best friend...;-D
Topic 2 of 99 [Geo]: Vulcanism
Response 100 of 997: Marcia (MarciaH) * Wed, Nov 3, 1999 (19:07) * 2 lines
...If the girl falls into lava - which is rather cool (a mere 2000°F or 1093°C).
You can evaporate your diamonds - they turn into Carbon Dioxide and burn with a blue flame, but then they are all gone!
Topic 2 of 99 [Geo]: Vulcanism
Response 101 of 997: Gi (patas) * Thu, Nov 4, 1999 (15:40) * 1 lines
I was thinking more along the lines of girl not falling into lava but home being washed by it... or whatever ;-)
Topic 2 of 99 [Geo]: Vulcanism
Response 102 of 997: Marcia (MarciaH) * Thu, Nov 4, 1999 (16:36) * 1 lines
Houses usually spontaneously combust when the lava approaches because of the intense heat...Then the lava paves over the entire place so nothing is left which is recognizable as having once been a home, yard, garden or proptecting wall around the place. It is urban renewal on a scale never imagined until you actually see it!
Topic 2 of 99 [Geo]: Vulcanism
Response 103 of 997: Marcia (MarciaH) * Thu, Nov 4, 1999 (22:13) * 31 lines
From Reuters Nwews Service
Send Page
Thursday - 20:57 11/04/99, EST
Mexican Volcano Shoots Smoke High Into The
Sky
MEXICO CITY (Reuters) - Mexico's Popocatepetl volcano sprang to life
Thursday morning after months of dormancy, sending smoke two miles into
the sky, officials said.
``Today, at 11:10 a.m. there was a moderately significant exhalation, lasting
19 minutes, that produced a smoke column of two to three kilometers in
height,'' the Interior Ministry said in a statement.
A series of tremors were also felt Wednesday at the volcano, 40 miles
southeast of Mexico City, from where 18 million residents can sometimes
see the volcano through the smog.
Ash was expected to rain on nearby communities. Mexico City airport was
placed on alert and some flights were delayed, airport officials said.
The government said there had been no significant change in activity at the
volcano, and that a yellow alert remained in place, prohibiting access within a
three-mile radius.
A yellow alert means that Popocatepetl, which last provoked safety warnings
in February, could erupt in weeks or months but probably no sooner.
Topic 2 of 99 [Geo]: Vulcanism
Response 104 of 997: Marcia (MarciaH) * Thu, Nov 4, 1999 (22:31) * 19 lines
On the best kids volcano site this letter and answer (by a Geologist I know personally!!!)http://volcano.und.nodak.edu/vwdocs/frequent_questions/grp13/question2153.html
dear srs: if the Popocatepetl volcano eruption could lava arrive to
Mexico City?
Alessandra
Hi Alessandra,
No, there won't be any lava from Popocatepetl getting to Mexico City. Popocatepetl does not produce very much lava and that
which it does produce is very viscous and slow-moving. Instead of flowing down the slopes it piles up into what is called a
dome. Popocatepetl is much more likely to produce explosive eruptions. These have already managed to spread ash all the
way to Mexico City, but the effects were not particularly serious. The biggest danger is from pyroclastic flows and lahars. These
are an immediate threat to the towns on the slopes of the volcano itself, and in the worst case scenario might affect Puebla, but
not Mexico City.
Sincerely,
Scott Rowland
Topic 2 of 99 [Geo]: Vulcanism
Response 105 of 997: anne hale (ommin) * Fri, Nov 5, 1999 (20:27) * 0 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 106 of 997: Marcia (MarciaH) * Fri, Nov 5, 1999 (20:52) * 1 lines
Well, it worked in Drool - guess I'll have to hunt thru telnet tomorrow te see what went wrong with your post here. Hmmm...thought we had it fixed!
Topic 2 of 99 [Geo]: Vulcanism
Response 107 of 997: Wolf (wolf) * Mon, Nov 8, 1999 (20:25) * 1 lines
did you guys notice the forgotten forget button has been remembered and is now part of the conference? (just thought i'd throw that in since every topic in this place is concerned about the fogotten forget button *grin*)
Topic 2 of 99 [Geo]: Vulcanism
Response 108 of 997: Marcia (MarciaH) * Mon, Nov 8, 1999 (20:51) * 1 lines
Yes, we did indeed see that. It is mentioned somewhere in this conference. Thanks for such lovely eruption buttons - I smile every time I come in here and admire them. I especially love the one without the frame.
Topic 2 of 99 [Geo]: Vulcanism
Response 109 of 997: Wolf (wolf) * Mon, Nov 8, 1999 (21:02) * 1 lines
so do i! *smile*
Topic 2 of 99 [Geo]: Vulcanism
Response 110 of 997: Marcia (MarciaH) * Mon, Nov 8, 1999 (21:23) * 1 lines
*sigh*
Topic 2 of 99 [Geo]: Vulcanism
Response 111 of 997: Gi (patas) * Tue, Nov 9, 1999 (10:23) * 1 lines
Why aren't the others made frameless as well?
Topic 2 of 99 [Geo]: Vulcanism
Response 112 of 997: Marcia (MarciaH) * Tue, Nov 9, 1999 (11:35) * 1 lines
Because Wolfie and I do not know how to do it. Only cfadm does, and he's not telling.
Topic 2 of 99 [Geo]: Vulcanism
Response 113 of 997: Marcia (MarciaH) * Sun, Jan 2, 2000 (14:37) * 2 lines
we have found a program online (nothing to download) which will make your frames transparent or
even different colors and reword your buttons. Very nice, Indeed. That is why they look gettr ( make that better) than before, but I need the font and size of same before I can change the interiors - which I now have to bother Wolfie about now...
Topic 2 of 99 [Geo]: Vulcanism
Response 114 of 997: Marcia (MarciaH) * Wed, Jan 5, 2000 (18:54) * 29 lines
The latest update on the Kilauea Eruption which began on January 4, 1983...
0645, January 5, 2000
Eruptive conditions are little changed from those of yester-
day. The ocean entries at the Lae`apuki bench continue to
be active. Lava continues to spread across the surface of
the west flow above and below Paliuli. The east arm of the
east flow remains active above Pulama pali.
This morning at 0550, at least four clusters of entry
points were feeding lava into the ocean from the front of
the Lae`apuki bench. There was, in addition, one sluggish
cascade over the old sea cliff near the west end of the new
bench.
Surface breakouts of pahoehoe toes continue just inland of
the bench. Much of the surface of the flow directly above
the old sea cliff has been renewed in the past several days.
Predawn glow this morning shows continued movement of the
reactivated part of the old easternmost flow. The location
of the glow suggests that the flow is active between about
1600 and 1100 feet elevation, above the top of Pulama
pali.
At least two small vents in the crater of Pu`u `O`o are
glowing this morning, but there is no flow or pond in the
crater. Seismic tremor near Pu`u `O`o is weak, and the tilt
at Kilauea summit is flat.
Topic 2 of 99 [Geo]: Vulcanism
Response 115 of 997: lidya maccarthy (livamago) * Fri, Jan 14, 2000 (22:33) * 1 lines
Hello, my dear! I finally made it...Do you know where to find a picture of the Irazu volcano in Costa Rica? My brother was just there, and he says it's beautiful. I've never seen a volcano in real life (my country is mercifully deprived of them), so pictures will have to do. ;-D
Topic 2 of 99 [Geo]: Vulcanism
Response 116 of 997: Marcia (MarciaH) * Sat, Jan 15, 2000 (00:59) * 4 lines
I did an altavista image search and this is the place you should start:
http://www.altavista.com/cgi-bin/query?pg=q&sc=on&q=Irazu&kl=en&stype=simage&wt=y
Loads of ggod things there for just pictures. If you wish more, go to web pages on the same search. Good luck! (and welcome back!!!)
Topic 2 of 99 [Geo]: Vulcanism
Response 117 of 997: lidya maccarthy (livamago) * Sat, Jan 15, 2000 (18:24) * 1 lines
Wow, it is beautiful! Thank you... (I thought the Best Western picture was hilarious...).
Topic 2 of 99 [Geo]: Vulcanism
Response 118 of 997: Marcia (MarciaH) * Sun, Jan 16, 2000 (11:59) * 1 lines
(so did I, and it was the first place I accessed.) Did your brother see any signs of activity at Irazu?
Topic 2 of 99 [Geo]: Vulcanism
Response 119 of 997: lidya maccarthy (livamago) * Sun, Jan 16, 2000 (20:20) * 1 lines
No, no activity, I think. I heard today that a volcano in Guatemala has started to erupt. Do you know the details? I must correct my previous statement, because I have indeed seen a volcano in real life; the Amatitlan peak in Guatemala, with its beautiful lake. I was just a child when I visited, though and we did not go to the top, but we could see the smoke. It has a baby volcano on one side, and that one was smoking too. Quite a site.
Topic 2 of 99 [Geo]: Vulcanism
Response 120 of 997: lidya maccarthy (livamago) * Sun, Jan 16, 2000 (20:21) * 1 lines
That is, quite a sight.
Topic 2 of 99 [Geo]: Vulcanism
Response 121 of 997: Marcia (MarciaH) * Mon, Jan 17, 2000 (00:22) * 2 lines
I heard an eye-witness on CNN radio telling of tall plumes of dark reddish hue rising high into the sky. The One URL I have for the Volcano no longer works. I shall hunt it down as soon as I can get some sleep and type more carefully.
(My New Year's Resolution!)
Topic 2 of 99 [Geo]: Vulcanism
Response 122 of 997: Maggie (sociolingo) * Sun, Feb 27, 2000 (14:05) * 10 lines
Saturday, 26 February, 2000, 21:51 GMT
Spectacular eruption of Icelandic volcano
A volcano in Iceland has erupted, sending clouds of ash and smoke up to ten kilometres into the air.
The Hekla volcano -- one of the highest in Europe -- is in the remote south-west of the island and the authorities say there's no danger to local people but aircraft have been warned not to fly over the area.
Witnesses say the eruption is a magnificent spectacle with red-hot lava flowing down the snow-covered slopes of the volcano. In Icelandic mythology, Hekla was believed to be one of the gates to hell and a haunt of witches.
Topic 2 of 99 [Geo]: Vulcanism
Response 123 of 997: Marcia (MarciaH) * Sun, Feb 27, 2000 (14:33) * 1 lines
Thanks, Maggie. I have hunted through all of the Icelandic volcanic-events links and they are not yet reporting anything. I will keep watch and post a picture and update as soon as I find one.
Topic 2 of 99 [Geo]: Vulcanism
Response 124 of 997: Maggie (sociolingo) * Sun, Feb 27, 2000 (14:46) * 1 lines
I went to the Icelandic news sources to see if I could find anything, but it is only on the BBC and few details. I think the last big ones for Hekla were 1991 and 1996.
Topic 2 of 99 [Geo]: Vulcanism
Response 125 of 997: Marcia (MarciaH) * Sun, Feb 27, 2000 (15:19) * 6 lines
There is a link I check when Vatnajokul happened
http://norvol.hi.is/bard3.html
- The Icelandic Volcano Observatory
http://xanadu.centrum.is/icerev/daily1.html#vat
- Daily updates (last was on Friday) of Iclandic news.
Topic 2 of 99 [Geo]: Vulcanism
Response 126 of 997: Marcia (MarciaH) * Sun, Feb 27, 2000 (17:24) * 17 lines
http://news.bbc.co.uk/hi/english/world/europe/newsid_659000/659187.stm
Iceland's volcanic spectacular
The volcano is an an uninhabited area Iceland's most active volcano, Mount Hekla, has erupted for the first time in almost 10 years, spewing columns of ash several kilometres into the sky.
Experts say the volcano poses no danger as it is situated in an uninhabited area about 120 km (75 miles) east of Reykjavik. The volcano, one of the highest in Europe, has erupted more than 20 times since the 11th century. In Icelandic folklore, it was believed to be one of the gates to purgatory.
Icelandic television said a lava flow from a fissure was estimated to be seven km (4.5 miles) long. Tousands of Icelanders have gone to witness the magnificent spectacle of red-hot lava and white snow. But the authorities warned drivers to beware of clouds of ash clogging up their engines. The 1,490-metre ( 4900-foot) volcano spewed ash all over Europe when it erupted last century. Seismologists say this latest incident resembles a 1991 eruption that lasted seven weeks.
No flights to or from Iceland had been cancelled. But despite the civil aviation authorities warning aircraft not to fly over the zone, a flying club announced that it was charging just over $100 for aerial tours of the volcano.
Topic 2 of 99 [Geo]: Vulcanism
Response 127 of 997: Marcia (MarciaH) * Sun, Feb 27, 2000 (17:28) * 1 lines
Next time I'm gonna remember to put "" around the left, center and right align command and they will not end up in a string on the left...*sigh*
Topic 2 of 99 [Geo]: Vulcanism
Response 128 of 997: Mike Griggs (mikeg) * Mon, Feb 28, 2000 (07:33) * 1 lines
that top picture looks like my wife-to-be when she's in a mood...
Topic 2 of 99 [Geo]: Vulcanism
Response 129 of 997: Marcia (MarciaH) * Mon, Feb 28, 2000 (10:45) * 2 lines
The top picture is the sort in which people here see Madame Pele looking benign/kind/sad/whatever and then the locals predict good or dire things. Your wife-to-be has a temper, does she? And, you are going into this with eyes open.
I think I'll worry some more about you - Poor Mike! He's got himself a Godess!
Topic 2 of 99 [Geo]: Vulcanism
Response 130 of 997: Marcia (MarciaH) * Mon, Feb 28, 2000 (14:32) * 28 lines
http://www.geo.mtu.edu/~boris/Latestnews.html
28 February 2000
POWERFUL EXPLOSIONS AT MAYON; HEKLA ACTIVITY DIMINISHES
Over the past two days, Mayon unleashed its strongest explosions so far, terrifying tens of
thousands of people living in the surrounding areas, and sending glowing pyroclastics hundreds of
meters into the sky. Press photos show spectacular incandescent fountains illuminating the summit
area, and the upper flanks covered by glowing projectiles. According to news reports, the latest
activity was purely explosive, following several days of predominantly effusive activity. Philippine
volcanologists noted that each explosion appeared to be stronger than its predecessor, and that the
climax might yet come. So far, more than 50,000 people have been evacuated. Many left the areas
around the volcano voluntarily, being impressed by the latest series of strong explosions. Local
authorities asked thousands of residents, who had left areas not under threat, to return home. The
refugees have been accomodated in evacuation centers, and news reports lament the lack of food
and the threat of diseases. Warnings have also voiced about the danger of lahars, which might be
caused by rainfalls washing the new pyroclastics from the slopes of the volcano.
LINKS TO OTHER MAYON INFORMATION
Mayon updates from the Philippine Institute of Volcanology and Seismology (PHIVOLCS)
ABS-CBN News (Philippine television news)
Links to on-line Philippine newspapers from Yahoo
Mayon Volcano Pictures:
Topic 2 of 99 [Geo]: Vulcanism
Response 131 of 997: Marcia (MarciaH) * Mon, Feb 28, 2000 (14:40) * 0 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 132 of 997: Marcia (MarciaH) * Mon, Feb 28, 2000 (14:43) * 6 lines
The top image above is a dublicate - sorry. Here is the intended one:
And, from Hekla:
Topic 2 of 99 [Geo]: Vulcanism
Response 133 of 997: Marcia (MarciaH) * Mon, Feb 28, 2000 (14:59) * 10 lines
Activity continues at Mayon Volcano, with several eruptions over the past
two days, and two powerful eruptions today (Mon. Feb. 28). There are
several news reports available online.
(for example, http://news.lycos.com/headlines/Science/)
Updates and general information on Mayon may be found at the Philippine
Institute of Volcanology and Seismology (PHIVOLCS) website:
http://www.phivolcs.dost.gov.ph/Volcanoes/Mayon/MayonIndex.html
Topic 2 of 99 [Geo]: Vulcanism
Response 134 of 997: Ginny (vibrown) * Mon, Feb 28, 2000 (22:59) * 1 lines
Amazing pictures and links! "Mother earth" is certainly restless these days...
Topic 2 of 99 [Geo]: Vulcanism
Response 135 of 997: Marcia (MarciaH) * Mon, Feb 28, 2000 (23:15) * 1 lines
either that or we are more aware of it because I am poking at her all day to find out what is happening. It is amazing to have people posting local weather from all over the world. What a luxury and a joy! How's Boston this evening?
Topic 2 of 99 [Geo]: Vulcanism
Response 136 of 997: Ginny (vibrown) * Mon, Feb 28, 2000 (23:43) * 3 lines
It's been rather warm (in the 40's F) and rainy for the past few days. It's been nice to get rid of all that dirty snow and ice. Looks like it might get up to the 50's this week...that's balmy for this time of year!
How are things in Hawaii? Is Pele still rumbling, or have the tremors calmed down for now?
Topic 2 of 99 [Geo]: Vulcanism
Response 137 of 997: Marcia (MarciaH) * Tue, Feb 29, 2000 (10:18) * 1 lines
Kilauea appears to have quieted down but the eruption continues on at its usual steady rate. It is still dark out as I write this, but it should be warm and sunny again...just another same old - same old day in Paradise *grin*
Topic 2 of 99 [Geo]: Vulcanism
Response 138 of 997: Ginny (vibrown) * Tue, Feb 29, 2000 (10:49) * 1 lines
Must you rub it in??? ;-)
Topic 2 of 99 [Geo]: Vulcanism
Response 139 of 997: Marcia (MarciaH) * Tue, Feb 29, 2000 (11:09) * 1 lines
...You asked...*smile* At least you are not mowing your lawn yet. Ours is deep enough to hide tigers and nasty things like that. We need a yard service!
Topic 2 of 99 [Geo]: Vulcanism
Response 140 of 997: Ginny (vibrown) * Tue, Feb 29, 2000 (11:28) * 3 lines
I also realize that you have your share of storms, earthquakes, etc.
It's only in the middle of winter that I start to dream of warmer climates. When the summer hits, I head for the air-conditioning and wonder why anyone would want to live in warmer places. (I can't deal with giant bugs, either.)
Topic 2 of 99 [Geo]: Vulcanism
Response 141 of 997: Marcia (MarciaH) * Tue, Feb 29, 2000 (12:10) * 1 lines
...and free-range lizards all over your house... Inside?!
Topic 2 of 99 [Geo]: Vulcanism
Response 142 of 997: Ginny (vibrown) * Tue, Feb 29, 2000 (12:19) * 1 lines
I forgot about the geckos...that would take some getting used to, but better them than the bugs, I guess.
Topic 2 of 99 [Geo]: Vulcanism
Response 143 of 997: Marcia (MarciaH) * Tue, Feb 29, 2000 (12:25) * 1 lines
Yup! They eat the bugs - and each other - then *bleep* on your picture frames, window sills, curtains, etc. The cat usually gets the lizards so we have far fewer of them than before the cat adopted us.
Topic 2 of 99 [Geo]: Vulcanism
Response 144 of 997: Maggie (sociolingo) * Thu, Mar 2, 2000 (17:21) * 1 lines
I like geckos and I'm not too keen usually on lizards. We always hoped to have them in our African houses - they actually like mosquitoes and can put away a surprising amount. I think they're sweet!
Topic 2 of 99 [Geo]: Vulcanism
Response 145 of 997: Marcia (MarciaH) * Thu, Mar 2, 2000 (18:03) * 1 lines
I think they're sweet, too. I take the babies outside so the big ones don't eat them. One night I heard crunching noises in the walkway. I turned on the front light to see what was happening, and there was a large Gekko (7" end to end) eating a large cockroach. Yup! Druther have gekkos any day of the week! Ours chirp, too!
Topic 2 of 99 [Geo]: Vulcanism
Response 146 of 997: Maggie (sociolingo) * Fri, Mar 3, 2000 (14:15) * 1 lines
Oh how nice, I don't remember any of ours making any noises.
Topic 2 of 99 [Geo]: Vulcanism
Response 147 of 997: Marcia (MarciaH) * Fri, Mar 3, 2000 (14:24) * 1 lines
I think ours are the only ones in the world which do...though there may be some other Polynesian ones which do also. It is very cute! And, no, for those wondering, they do not fall on you!
Topic 2 of 99 [Geo]: Vulcanism
Response 148 of 997: Maggie (sociolingo) * Fri, Mar 3, 2000 (15:12) * 1 lines
I can confirm that, I've never had a gecko fall on me yet, unlike cockraoches, millipedes, ear wigs ............
Topic 2 of 99 [Geo]: Vulcanism
Response 149 of 997: Cheryl (CherylB) * Fri, Mar 3, 2000 (15:43) * 1 lines
Are geckos the ones that lick their eyes with their tongues? Still if they're eating their fill of insect life, it's a small habit to get used to. Much better than an exterminator, works for free and best of all, is environmentally friendly.
Topic 2 of 99 [Geo]: Vulcanism
Response 150 of 997: Maggie (sociolingo) * Fri, Mar 3, 2000 (15:56) * 1 lines
African geckos are pink, sort of albino-ish, with bulging eyes, but I don't remeber them licking their eyes with their tongues, cone to that I don't remember ever seeing thier tongues! Marcia???
Topic 2 of 99 [Geo]: Vulcanism
Response 151 of 997: Marcia (MarciaH) * Fri, Mar 3, 2000 (16:16) * 1 lines
No, but they are pretty small. And I am sure they are very quick with that tongue unlike the pretend one on the Telly ads. We have two kinds. The ones which are supposedly are from Japan are larger, pink and almost albino (you can see the eggs in them when they are on your windows.) The Hawaiian are darker and change colors a bit more than the big pink ones and they are smaller and are prey for the bigger pink ones. Much rather have them than bugs - and we have earwigs, too!!!
Topic 2 of 99 [Geo]: Vulcanism
Response 152 of 997: Marcia (MarciaH) * Fri, Mar 3, 2000 (22:32) * 23 lines
Babies Born As Volcano Erupts
TABACO, Philippines (Reuters) - Nine babies have been born in cramped
evacuation centers in the central Philippines where refugees from the wrath of
Mayon volcano have been sheltering for over a week, relief officials said on
Friday.
One of the new mothers, 35-year-old Asuncion Broncate, gave birth to her
seventh child early on Thursday in a room at a school in Tabaco town, which
was serving as a temporary shelter for 10 families.
``Despite our miserable condition it is hot, there is no electricity everything
went smoothly with the grace of God,'' Broncate told Reuters as she
breastfed her one-day-old baby boy at the Panal Bangkilingan Elementary
School.
Broncate said she gave birth without the help of a midwife or any trained help
at dawn on Thursday.
Other evacuees in the school, mostly farmers living on the slopes of the 2,460
meter (8,000 foot) volcano, later took the baby to a nearby hospital for an
examination, she said.
Veronica Madulid, a provincial disaster official, said eight other babies were
born earlier in the week at other centers around Mayon.
More than 65,000 people are currently housed in various evacuation centers
in Albay province since Mayon first began erupting on February 24.
The volcano killed 77 people in its last major eruption in 1993.
Topic 2 of 99 [Geo]: Vulcanism
Response 153 of 997: Marcia (MarciaH) * Sat, Mar 11, 2000 (23:27) * 4 lines
Ginny's Photrograph published on http://ourworld.compuserve.com/homepages/hornak/
I enlarged it but do not recognize where it was taken and I was with her when she took it!
Topic 2 of 99 [Geo]: Vulcanism
Response 154 of 997: Marcia (MarciaH) * Sat, Mar 11, 2000 (23:30) * 3 lines
This is the slightly enlarged version - a beautiful and dramatic shot:
Topic 2 of 99 [Geo]: Vulcanism
Response 155 of 997: Ginny (vibrown) * Sun, Mar 12, 2000 (01:10) * 9 lines
Thanks, Marcia!
Actually, I took that picture (along with *many* more) the day that David, Polly and I hiked out to the lava shield near Pu'u O'o. I think it was called "Kupaianaha" (not sure about the spelling). Marcia was with us the day before, when we hiked out to where the lava was flowing into the ocean.
That was quite a hike...it took most of the day! We scratched the paint on the sides of the rental car just getting to our starting point for the hike! I enjoyed the jiffy pop, popped on a hot vent!
The picture was just published in the "Dictionary of Volcanology and Seismology". It's a Spanish-to-English/English-to-Spanish translation dictionary of volcanology and seismology terms. The author, Ken Hornak, found
my web site last year, and asked permission to use the photo on the title page of the book. My sample copy of the book, signed by the author, came in the mail yesterday. It's a first for me!
Topic 2 of 99 [Geo]: Vulcanism
Response 156 of 997: Marcia (MarciaH) * Sun, Mar 12, 2000 (15:59) * 2 lines
Congratulations to a puvblished photographer! I remember that hike but I did it with the graduation bunch in the day time and did the Jiffy-pop thing, too.
I recall being told (and I did not doubt it for a second) that it was gonna be a tough hike at night and that I should probably not go with you-all. I'm sure, from my hike of the same route that it was no easy thing to negotiate.
Topic 2 of 99 [Geo]: Vulcanism
Response 157 of 997: Ginny (vibrown) * Mon, Mar 13, 2000 (23:35) * 1 lines
If I remember correctly, the hike to where the lava flowed into the ocean was at night, and you joined us. The hike to the sea shield was a much longer hike, and we did that the next day. It took the whole day, and I was pretty tired by the end of it...and I was in better shape than I am now! :-)
Topic 2 of 99 [Geo]: Vulcanism
Response 158 of 997: Marcia (MarciaH) * Tue, Mar 14, 2000 (12:09) * 5 lines
I remember hiking to the sea with you and have photos to prove it - some from you and some from David.
Ginny's latest and now I recognize the surroundings:
Topic 2 of 99 [Geo]: Vulcanism
Response 159 of 997: Marcia (MarciaH) * Tue, Mar 14, 2000 (20:21) * 27 lines
Mayon Volcano Bulletin
12 March 2000
An ash puff with height of about one kilometer was observed at 0903H
yesterday. The ash column was drifted to the northwest direction. The ash
ejection was caused by water that comes in contact with the still hot lava
deposits at the summit. And at 1242H, another minor billowing ash was seen
descending the Bonga Gully due to the detachment of the new lava deposit at
the upper slope. The elutriated ash cloud drifted to the west-southwest by
the prevailing winds.
During the rest of the past observation period the volcano was relatively
quiet. This was manifested by faint crater glow at the tip of the cone and
weak to moderate emission of steam. Sulfur Dioxide (SO2) emission rate
decreased from the previous reading of 4,300 tonnes per day (t/d) to 4,000
t/d.
Seismic activity consisted of 5 low-frequency volcanic quakes and 7
episodes of short-duration tremors. Slight deflation of the volcano edifice
continued to be recorded by ground deformation measurements via precise
leveling.
PHIVOLCS considers the moderate seismic levels, deflation of the volcanic
cone, moderate steam ad SO2 outputs including crater glow to be part of the
volcanic processes involving the gradual return to quiet conditions. At
this stage, however, these parameters are still above normal repose levels
such that Alert Level 4 remains hoisted over the volcano.
http://www.phivolcs.dost.gov.ph/Volcanoes/Mayon/MayonIndex.html
Topic 2 of 99 [Geo]: Vulcanism
Response 160 of 997: Marcia (MarciaH) * Mon, Mar 20, 2000 (11:51) * 36 lines
VOLCANOES - updates
Mayon (Philippines) Summitcrater dome growth and escalating eruptions
herald evacuations
Barren Island (India) Naval aircraft flight crew sights unconfirmed
"volcanic emission of smoke"
Piton de la Fournaise (Reunion Island) A new eruption in February 2000
begins venting lava flows
Nyamuragira (Zaire) As 27 January eruption began, witnesses assumed they
heard artillery fire
Stromboli (Italy) 1999 seismic summary and some strongerthanusual eruptions
Kilauea (Hawaii) Ground deformation continues through June; earthquake
swarms begin in December
Tungurahua (Ecuador) More than twofold increase in longperiod earthquakes
during December
Pacaya (Guatemala) Map of new lava flows, satellite data, and perspective
on the 16 January eruption
Fuego (Guatemala) Satellite data reveals hot spot; field observers see
JanuaryFebruary ash puffs
Popocatepetl (Mexico) Increased number of exhalations and new dome growth
in late February
Soufriere Hills (Montserrat) Stillvigorous, potentially destructive
eruptions during JulyNovember 1999
http://www.volcano.si.edu/gvp/
Topic 2 of 99 [Geo]: Vulcanism
Response 161 of 997: Marcia (MarciaH) * Sun, Mar 26, 2000 (14:43) * 3 lines
This photo was taken some years ago when he and another geologist would spend several days in the field. They slept and stored all things under that rusty-roofed structure. It got covered by cinders regularly and had to be dug out. As I recall this place ( just in front of that vent - Pu'u O'o) was called Camp 7 and was covered entirely and permanently just as the 6 camps before them had been. The items on the tripods are lasers and reflectors with which they measure the deformation of the entire mountain of Kilauea.
Topic 2 of 99 [Geo]: Vulcanism
Response 162 of 997: Marcia (MarciaH) * Sun, Mar 26, 2000 (17:39) * 40 lines
STROMBOLI ON-LINE and ITALY'S VOLCANOES: THE CRADLE OF VOLCANOLOGY
proudly present:
Video clips of a paroxysmal eruptive episode at the Southeast Crater of
Mount Etna(Sicily), 15 February 2000, filmed by British film maker David
Bryant
A series of video clips in Quicktime format (.mov) showing the spectacular
eruptive episode at the Southeast Crater on Etna of 15 February 2000 has
been posted simultaneously at "Stromboli On-line" and "Italy's Volcanoes:
The Cradle of Volcanology". The videos, which range from 1.5 to 3.5 MB in
size, show all main stages of the spectacular event from the initial
Strombolian activity over the escalation and the rise of huge lava fountains
to the decline and end. We believe that this is extraordinary footage of a
volcanic eruption and are grateful to David Bryant for his availability to
share his material with volcano enthusiasts and volcanologists worldwide.
His full video will appear in a film about Mount Etna and Catania, which
will be broadcast later this year; information about this will be provided
timely to visitors of our web sites.
We have decided to post the video clips on both sites simultaneously,
because this will allow both U.S. and European visitors fast downloading. If
the connection to one of the sites is slow, you may thus switch to the other
site and see if this works faster. We also give tips about how to download
faster and without annoying ruptures of transmission, if you have a slow
line.
And this is where you will find the movie clips:
Stromboli On-line: http://stromboli.net/perm/etna/etna00av/index-en.html
Italy's Volcanoes: http://www.geo.mtu.edu/~boris/ETNA_15022000movie.html
Enjoy!
Topic 2 of 99 [Geo]: Vulcanism
Response 163 of 997: Maggie (sociolingo) * Mon, Mar 27, 2000 (04:32) * 1 lines
Got it - was in wrong topic earlier!
Topic 2 of 99 [Geo]: Vulcanism
Response 164 of 997: Marcia (MarciaH) * Mon, Mar 27, 2000 (15:01) * 1 lines
Got a cute one of him as a full-grown man....have I inflicted it on you, yet? It used to be visible in Spring Gallery on Porch conference.
Topic 2 of 99 [Geo]: Vulcanism
Response 165 of 997: Maggie (sociolingo) * Mon, Mar 27, 2000 (15:25) * 1 lines
I've got one - don't know if it's the same one though. You said it was your favourite.
Topic 2 of 99 [Geo]: Vulcanism
Response 166 of 997: Marcia (MarciaH) * Mon, Mar 27, 2000 (15:29) * 1 lines
You have the fav one, so far, that is...*smile*
Topic 2 of 99 [Geo]: Vulcanism
Response 167 of 997: anne hale (ommin) * Tue, Mar 28, 2000 (23:36) * 1 lines
wonderful pic. Marcia, now we have converted to netscape - didn,t realise how much better it is.
Topic 2 of 99 [Geo]: Vulcanism
Response 168 of 997: Marcia (MarciaH) * Wed, Mar 29, 2000 (14:06) * 1 lines
Finally! I told you (as they say)...it is true !
Topic 2 of 99 [Geo]: Vulcanism
Response 169 of 997: Ginny (vibrown) * Thu, Mar 30, 2000 (00:03) * 3 lines
That's a great picture of David! Was that close to where we went hiking (when I took the picture that just got published)? I remember seeing Pu'u 0'o when we were out there.
Wow, 7 camps buried by lava? I hope no one was *at* any of the camps when they got buried!!
Topic 2 of 99 [Geo]: Vulcanism
Response 170 of 997: anne hale (ommin) * Thu, Mar 30, 2000 (04:38) * 1 lines
Has the volcanic eruption due to come at any moment in Japan been reported. Also large earthquake in New Zealand today.
Topic 2 of 99 [Geo]: Vulcanism
Response 171 of 997: Marcia (MarciaH) * Thu, Mar 30, 2000 (10:33) * 37 lines
Nothing in here reported about the eruption, but my email is full of items from Dacid (Yes, Ginny, that is where you were! No one was endangered by the eruptions which buried any of the camps, thank goodness.) Did not know about the earthquake in NZ, but will post as soon as I get through here and wake up a little.
***************************
Usu Volcano, Japan crisis
***************************
Volcanic Advisory reports (nos. 1-7) on Usu Volcano, Hokkaido, Japan, were
issued from Japan Meteorological Agency (JMA) since 28 March. Number of
volcanic earthquakes around this volcano has increased since 8 a.m. (JST),
27 March; 16 times in 27 Mar. and 599 in 28 Mar. (including 68
felt-earthquakes) at the JMA site about 2 km south of the summit. At 07:08,
29 March, the quake of M3.4 occurred on this volcano. According to the Usu
Volcano Observatory, the hypocenter of the earthquakes locates on the
northern slope of the volcano. Neither volcanic tremor nor visible change
in fumarolic gas had not been observed by the 28 March night.
National Coordination Committee of Volcanic Eruption Prediction (Chaired by
Prof. Yoshiaki Ida, Univ. of Tokyo) commented a high possibility of
imminent eruption in this volcano in the 28 March evening. JMA is also
calling the local people's attention to mud flows triggered due to snow
melting by eruption. Hot spring resort locates on the northern foot of the
volcano, and about 1,600 guests stayed this night. However, more than 400
persons living around the volcano actively took refuge to safety places
like distant schools by the 28 March night, according to the attentions by
local governments.
Historical eruptions occurred in 1663, 1769, 1822, 1853, 1910, 1943-45
(Showa-shinzan lava dome eruption), and 1977-78. According to Akihiko
Tomiya, Geological Survey of Japan, precorsory phenomena of these
eruptions, mainly volcanic earthquake events, before eruptions lasted from
32 hours (1977-78) to 6 months (1943-45 eruption). Most of them began with
the Plinian phase, followed by pyroclastic flows and, then, dome growth.
The volume of tephra is 0.05 c.km for the 1943-45 eruption to 2.5 c.km for
the 1663 eruption. Information on Usu Volcano is in the site,
http://uvo.sci.hokudai.ac.jp/.
Topic 2 of 99 [Geo]: Vulcanism
Response 172 of 997: Marcia (MarciaH) * Fri, Mar 31, 2000 (17:07) * 74 lines
Japanese Volcano Eruption Forces 15,000 to Flee
DATE (Reuters) - Japan's snow-capped Mount Usu volcano erupted on
Friday, belching forth vast clouds of smoke and ash and forcing 15,000
people to flee their homes.
The 2,402-foot volcano, among Japan's most active, sent rocks hurtling into
the air as plumes of dark gray smoke streaked with blue lightning billowed
from the conical mountain.
Residents ran for cover, holding towels over their mouths as the smell of
sulfur pervaded the air.
Onlookers said they could taste grit from the eruption that hurled ash as high
as 8,850 feet into the sky. A carpet of ash coated cars and houses.
Tremors were jolting the hot spring resort area on the northern island of
Hokkaido as the eruption continued, Meteorological Agency official Manabu
Komiya told reporters.
Ash, volcanic rocks and mudslides had flowed toward the small town of Abuta
and the navy and the Coast Guard were deployed to evacuate the entire
population of some 2,000 from homes perched precariously between the
mountain and the sea.
Officials said four naval ships, five Coast Guard vessels and two military
helicopters had plucked residents to safety.
``Depending on developments, the eruption could cause even bigger damage,''
Prime Minister Keizo Obuchi said. ``The government will do whatever it can to
deal with the situation.''
Sailors on the naval vessels reported mudslides slipping down the
cone-shaped mountain toward Abuta, but navy officials said later these were
small.
Officials said there were no reports of casualties.
Mount Usu last erupted in 1978 after a series of earthquakes that gave birth
to a new and smaller volcano by its side. Mudslides triggered by that eruption
killed three people.
Troops had already helped to evacuate more than 15,000 people from towns
around the foot of the volcano and they were being housed in schools and
public halls.
Officials said they were establishing emergency post offices and banks to
allow residents easy access to their money.
FURTHER ERUPTIONS POSSIBLE
Government experts said another big explosion appeared unlikely but it could
take some time until the volcano settled down and more eruptions were
possible from new craters.
``The fact that the ash cloud rose so high suggests the force of the eruption
was strong. We can't dismiss the chance of other developments, like magma
moves,'' said Yoshiaki Ida, chairman of the government's volcano experts
panel.
Snow was falling heavily, further coating the slopes of the volcano still
shrouded by billowing smoke from explosions of gases from five craters on
the mountain's western slope.
Officials said initial assessments showed the eruption had not been as large
as first expected, but further blasts could not be ruled out. Thousands of
earthquakes had rumbled through the region since Sunday as the mountain
prepared to blow its top.
``Mount Usu has had seven significant eruptions that we know of, and at no
time has it ended quickly with only a small scale eruption, said Yoshio
Katsui, a professor at Hokkaido University.
The plume of smoke was not as large as the one spewed out by Mount Usu's
last eruption in 1978.
``It looks smaller than before,'' said one middle-aged woman watching the
smoke pillar from the shore of nearby Lake Toya.
Train services in the area had been disrupted, some flights had been diverted
and roads blocked off, officials said.
Officials warned residents to beware of mudslides amid predictions of heavy
rain later on Friday night because snow on the mountain, believed to be 11 to
31 inches thick, could melt rapidly.
Some 3,300 troops were providing food, water and blankets for evacuees.
Others were on reconnaissance missions around the mountain, including
some in helicopters.
A Hokkaido government official said 55,000 people living in five towns around
the foot of the mountain, including the hot spring resort town of Toya, could
be affected by an eruption.
Cabinet ministers, keen to appear on top of the situation after past criticism
for slow response to disasters, huddled at a crisis center at the prime
minister's residence to monitor events.
Officials warned there was a chance that an eruption at Mount Usu could
mimic the deadly flow of superheated gas and ash from Mount Fugen in
southern Japan in 1991, which killed 43 people.
Topic 2 of 99 [Geo]: Vulcanism
Response 173 of 997: Marcia (MarciaH) * Wed, Apr 12, 2000 (21:11) * 25 lines
From David:
************************************************
Stromboli On Line: Etna Video and smoke rings
************************************************
May we bring to your attention the fact that now
STROMBOLI ON-LINE's 1999-Etna videocassette is available,
featuring South East Crater lava flows and hornito activity, and
Bocca Nuova paroxysm with the "small scale pyroclastic flow".
All footage was digitally recorded and processed (58min; VHS-PAL,
VHS-NTSC upon request); original sound only, no commentary.
Written explanations in German, English and Italian are added.
For further details please consult our website:
http://stromboli.net/shop/index-en.html
We would also like to ask if any of you are aware of publications
regarding «smoke rings». We were able, in February 2000, to document
exceptionally beautiful and long-lasting rings on Etna, and this arose
an incredible interest about their nature. We would be therefore glad
to be able to present a rather complete list of scientific references
regarding their origin. Etna's «ring world» can be seen at
http://stromboli.net/perm/etna/etna00b/index-en.html
Topic 2 of 99 [Geo]: Vulcanism
Response 174 of 997: Marcia (MarciaH) * Wed, Apr 12, 2000 (21:40) * 4 lines
Go to this remarkable page of pictures - below is one of them:
http://educeth.ethz.ch/stromboli//perm/etna/etna00b/index-en.html
Topic 2 of 99 [Geo]: Vulcanism
Response 175 of 997: Ginny (vibrown) * Wed, Apr 12, 2000 (22:54) * 1 lines
Amazing pictures! I love the smoke rings.
Topic 2 of 99 [Geo]: Vulcanism
Response 176 of 997: Marcia (MarciaH) * Wed, Apr 12, 2000 (22:59) * 1 lines
There are incredible pictures on that web page, but I love the one I posted here. Never saw anything like it! Well, I did see Pu'u O'o do that during one episode way back in its infancy...and if someone else had not mentioned it, I would have thought I was seeing things.
Topic 2 of 99 [Geo]: Vulcanism
Response 177 of 997: Ginny (vibrown) * Wed, Apr 12, 2000 (23:08) * 1 lines
I would have thought I was seeing things, too! Pu'u O'o didn't do that while I was there (but I can't complain about what I *did* see).
Topic 2 of 99 [Geo]: Vulcanism
Response 178 of 997: Marcia (MarciaH) * Thu, Apr 13, 2000 (00:08) * 1 lines
Yup! You got close enought to get your feet "wet", as I recall.
Topic 2 of 99 [Geo]: Vulcanism
Response 179 of 997: Marcia (MarciaH) * Mon, May 1, 2000 (16:52) * 47 lines
***************************************
Submarine eruption: Madagascar Plateau
***************************************
A probable submarine eruption was observed during the April 24-25 night by
the solitary navigator Philippe MONNET, who is doing the world tour in
inverse order, near 30°S-45°E where there is a seamount, on the Madagascar
Plateau, the top of which is around 300-400 m. below sealevel.
He observed very big dark and white plumes up to 10 000 m. high, may be
more, glowing gleams in the base of the plumes issued of the sea, and many
flash of lightning. The sea was especialy rough in the zone.
He observed this phenomena during more than 14 hours, and April 25 in the
evening, many milles in the West, he could always see the glowing plume.
April 23 (4:16 UT) the Piton de la Fournaise Observatory recorded an
earthquake around 1 000 km in the West sector of Reunion Island. Relationship?
P. Lanier (Monnet's routeur) followed plumes on satellite images during
this period.
***************************************
Submarine eruption: Azores
***************************************
From: Hugh McNichol
Photos of the ocean surface during an eruption of an underwater
volcano near the Azores can be found at:
http://www.acores.net/fotos/foto_iris/
According to a marine historian living on the Azores, this underwater
volcano is only about 5 km offshore and the summit was 400 meters
below the surface in the summer, and it is only 200 meters below the
surface now.
According to the web sites below, the submarine eruption near Terceira,
Azores Islands, which began late in 1998 is still continuing as of
Feberuary 2000, albeit at a low and flucuating level. Pictures are
available at the first URL below.
http://www.virtualazores.com/crise99/index.html
Following from:
http://www.geo.aau.dk/palstrat/tom/santorini_homepage/ongoing_eruptions.htm#
terceira
26 February 2000
Ash and gas emission from the submarine eruptive fissure that started
erupting in late 1998 is still continuing at Terceira, Acores. For over one
year, the eruption is continuing at low, fluctuating levels.
Topic 2 of 99 [Geo]: Vulcanism
Response 180 of 997: Ginny (vibrown) * Tue, May 9, 2000 (00:25) * 72 lines
Sorry if this is a duplicate...haven't had a chance to catch up on all the Geo topics yet. From http://www.jpl.nasa.gov/releases/2000/jovianduststream.html
MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov
Contact: Jane Platt, (818) 354-0880
FOR IMMEDIATE RELEASE May 3, 2000
IO'S VOLCANOES SPLATTER DUST INTO THE SOLAR SYSTEM
Fiery volcanoes on Jupiter's moon Io are the main source of dust streams that flow from the Jupiter system into the rest of the solar
system, according to new findings from NASA's Galileo spacecraft analyzed by an international team of scientists.
The scientists, led by Amara Graps of the Max Planck Institute of Nuclear Physics in Heidelberg, Germany, analyzed the frequency of
dust impacts on Galileo's dust detector subsystem. They found peaks that coincided with the periods of Io's orbit (approximately 42 hours)
and of Jupiter's rotation (approximately 10 hours).
Although dust scientists had suspected Io as the source of the dust streams, it was difficult to prove. They ruled out several possible
sources, including Jupiter's main ring and Comet Shoemaker-Levy 9, but Jupiter's gossamer ring and Io remained as candidates. The dust
scientists studied several years of Galileo data to show that the motion of the dust stream particles is strongly influenced by Jupiter's
magnetic field, with a unique signature that could exist only if Io were the main contributor to the dust streams.
"Now, for the first time we have direct evidence that Io is the dominant source of the Jovian dust streams," said Graps, lead author of
a paper on the findings that appears in the May 4 issue of the journal Nature.
The Jovian dust streams are intense bursts of submicron- sized particles (as small as particles of smoke) that originate in Jupiter's
system and flow out about 290 million kilometers (180 million miles), or twice the distance between Earth and the Sun. They were first
discovered in 1992 by the dust detector onboard the Ulysses spacecraft during its Jupiter flyby.
"The escape of dust from the Jovian system in 1992 was a total surprise," said Dr. Mihaly Horanyi, a dust plasma physicist at the
Laboratory for Atmospheric and Space Physics, Boulder, CO, and co-author of the paper. Since 1995, the Galileo dust detector, a twin
to the Ulysses instrument, has observed the streams, both while the spacecraft was en route to Jupiter and within the Jupiter system.
Very, very early in the history of our solar system, before and during the formation of the planets, small dust grains were much more
abundant. These charged grains were influenced by magnetic fields from the early Sun, much as the dust on Io is affected by Jupiter's
magnetic field today. Thus, studies of the behavior of these dust grains may provide insight into processes that led to the formation of the
moons and planets in our solar system.
"The dust from the Jovian dust streams is clearly magnetically-controlled dust," said Dr. Eberhard Gruen of the Max Planck Institute.
"Dust particles carry information about charging processes in regions of the Jovian magnetosphere, where information is otherwise sparse
or unknown." Gruen built the dust detectors for several spacecraft, including Galileo, Ulysses and Cassini.
These new results provide a useful window on Io. In-situ dust measurements can monitor Io's volcanic plume activity, complementing
observations made by Galileo and from Earth-based telescopes.
The Jovian dust streams, with their Io source, are minor when compared to the huge amounts of dust created in the solar system by
comet activity and asteroid collisions. Nonetheless, they add to the variety of dust sources in the solar system. In fact, the Jovian dust
streams travel so fast that some particles can actually leave the solar system to join the local interstellar medium -- the gas and dust that fill
the space between stars.
In December 2000, during a joint observation of Jupiter by Galileo and Cassini, scientists will have a unique opportunity to study the
Jovian dust streams using dust instruments on both spacecraft.
In addition to Graps, Gruen and Horanyi, authors on this paper are Dr. Harald Krueger, Andreas Heck and Sven Lammers of Max
Planck, and Dr. Hakan Svedhem of the European Space Research and Technology Centre in Noordwijk, the Netherlands. This work was
supported by the German space agency, Deutsches Zentrum fuer Luft-und Raumfahrt E.V. (DLR).
More information on the Galileo mission is available at http://galileo.jpl.nasa.gov .
The Max Planck, Heidelberg Dust Group web site is at http://galileo.mpi-hd.mpg.de/ .
The Galileo, Cassini and Ulysses missions are managed by the Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of
Space Science, Washington, DC. JPL is managed by the California Institute of Technology in Pasadena.
#####
5/3/00 JP
#2000-042
Topic 2 of 99 [Geo]: Vulcanism
Response 181 of 997: Marcia (MarciaH) * Tue, May 9, 2000 (00:27) * 1 lines
I posted similar stuff before the beginning of the year in Geo 24 - which is why it was created - for Volcanoes other than on Earth. Thanks!
Topic 2 of 99 [Geo]: Vulcanism
Response 182 of 997: Ginny (vibrown) * Tue, May 9, 2000 (00:29) * 1 lines
Ah...wasn't sure which topic it belonged in...a little bit of "overlap"
Topic 2 of 99 [Geo]: Vulcanism
Response 183 of 997: Marcia (MarciaH) * Tue, May 9, 2000 (00:31) * 1 lines
That's really fascinating. I wonder how it will effect the magnetosphere over which Mike has now taken control on Geo 35 ( check out the cool diagram I found)
Topic 2 of 99 [Geo]: Vulcanism
Response 184 of 997: Marcia (MarciaH) * Tue, May 9, 2000 (00:36) * 1 lines
Not to worry - we'll catch 'em one way or the other. I often link it by saying look on topic whatever post who... I hope it is being read. I think I shall alert mike to your post so we can decide what is gonna happen to us. Btw, I now post all space news in topic 34 just for that purpose. I imagine they will come out with headlines about this, too...
Topic 2 of 99 [Geo]: Vulcanism
Response 185 of 997: Ginny (vibrown) * Tue, May 9, 2000 (01:03) * 3 lines
You certainly have been busy around here...gonna take me a while to catch up on all the postings! :-)
Well, it's 2am here, so good night all!
Topic 2 of 99 [Geo]: Vulcanism
Response 186 of 997: Marcia (MarciaH) * Tue, May 9, 2000 (12:10) * 1 lines
Oh, Ginny, they're worth it. Lots of good stuff in here lately (as usual, actually...) Welcome home!
Topic 2 of 99 [Geo]: Vulcanism
Response 187 of 997: Marcia (MarciaH) * Fri, May 26, 2000 (21:42) * 89 lines
Observations in late May 2000 by NZ geologists showed that the famous
Kavachi submarine volcano in the Solomon Islands is once again erupting,
with spectacular bomb ejections and possible island formation.
From: http://www.gns.cri.nz/news/release/volcisland.htm
NEWS RELEASE, 25 MAY 2000
NZ SCIENTISTS WATCH FIERY BIRTH OF NEW PACIFIC ISLAND
Two New Zealand scientists were part of an international team who this week
witnessed the dramatic birth of a new volcanic island near the Solomon
Islands. The rare observation was made during an investigation of seafloor
volcanic activity and associated mineral formation in the Bismark and
Solomon seas north of Australia.
Marine geochemist Gary Massoth and mineral geologist Cornel de Ronde, both
of the Institute of Geological & Nuclear Sciences Limited (GNS), were part
of an international team on the CSIRO research ship Franklin who made a
comprehensive study of the island-building eruptive activity.
The scientists found the shallow Kavachi seamount, which had been dormant
for nine years, had started a new phase of eruptive activity. Kavachi, in
the Solomon Island chain of volcanoes, is only 30km from the boundary of
the Indian and Australian tectonic plates.
A roughly conical feature rising from a seafloor depth of 1100m, Kavachi is
about eight kilometres in diameter at its base and has produced ephemeral
islands at least twice in the past century.
" When we arrived at Kavachi, we found violent eruptions taking place every
five minutes,’’ Mr Massoth said from Darwin today. " The eruptions were
ejecting molten lava up to 70 metres above sea level, and sulphurous steam
plumes rose to about 500 metres. At night we were treated to a spectacular
fireworks display with the red glow of eruptions continuing."
The peak of the volcano was forming a sandy ashen beach two metres below
sea level with regular violent bomb-like eruptions.
The ship approached to within 750 metres of the eruption centre and found
that the volcano had grown substantially since it was last surveyed in
1984. The scientists were able to sample freshly formed volcanic rocks from
the flanks of the erupting volcano.
" This was an unprecedented opportunity and has given us valuable
geological information. We also systematically sampled gases and seawater
at various depths around the perimeter of the volcano something that has
not been achieved before with an erupting submarine volcano.
" We detected particle and chemical plumes from the eruption at least 5
kilometres from the centre of the volcano. This has provided valuable
information about the impact of active volcanoes on ocean chemistry."
Mr Massoth said Kavachi differed from Brothers volcano, the largest and
most active submarine volcano north east of White Island, in that Brothers
was deeper and hydrothermally active while Kavachi was shallow and
volcanically active.
" Hot rock, or lava, predominates at Kavachi while hot water predominates
at Brothers." Hydrothermal fluids were venting from Brothers volcano at
about 300oC against 100oC at Kavachi. Hotter fluids react with the volcano
host rocks more efficiently and are more heavily laden with dissolved
minerals."
Observations at Kavachi showed that lava being quickly quenched in seawater
did not produce a strong chemical plume in the ocean, unlike the active
volcanoes northeast of White Island which vent large volumes of
hydrothermal fluids and heat into the ocean.
" Kavachi has confirmed our observations that forearc volcano chains, such
as the Kermadec chain north east of White Island, contribute significantly
to the global inventory of heat and chemical emissions entering the oceans.
" The work we have been doing in New Zealand waters is effectively
re-writing the textbook on submarine volcanism."
About 80 percent of the world’s volcanism occurred in the ocean and only a
small proportion of all submarine volcanoes had been systematically
surveyed with scientific equipment, Mr Massoth said.
At another location, the scientists dredged up what they believe is a
world-record size "black smoker" a 2.7m-high chimney prised from an
active volcanic vent at a depth of 1700m. Black smoker chimneys are packed
with minerals typically 1000 to 10,000 more concentrated than background
levels in seawater. The chimney was expected to be rich in silver, zinc and
gold, Mr Massoth said.
John Callan
Communications Co-ordinator
Institute of Geological & Nuclear Sciences Limited
Topic 2 of 99 [Geo]: Vulcanism
Response 188 of 997: Marcia (MarciaH) * Fri, May 26, 2000 (22:31) * 4 lines
Kavachi submarine volcano in the Solomon Islands is once again erupting,
with spectacular bomb ejections and possible island formation.
Topic 2 of 99 [Geo]: Vulcanism
Response 189 of 997: Maggie (sociolingo) * Sat, May 27, 2000 (04:29) * 1 lines
I'm glad i came and looked - that's a great photo
Topic 2 of 99 [Geo]: Vulcanism
Response 190 of 997: Marcia (MarciaH) * Sat, May 27, 2000 (12:08) * 1 lines
Thanks! There is nothing quite like watching an island emerge from the sea or watching what used to be a huge pit crater fill, then build a small mountain which becomes a named hill on maps. It is like peeking while God was creating the world...He has not stopped and for that I am eternally grateful. This island has grown by 400 sq acres since the current eruption began!
Topic 2 of 99 [Geo]: Vulcanism
Response 191 of 997: Marcia (MarciaH) * Sat, May 27, 2000 (17:04) * 7 lines
A few eye-witness accounts from a Honolulu guy who has had rather negative volcano experiences compared with mine:
I was in a 747 about 15 years ago flying somewhere over india..there had been a volcano erruption hundreds of miles away but the cloud at risen something like 60 thousand feet...the plane flew thru the cloud and all engines quit..pilot got them started back...
speaking of which..about 8-9 years ago I was on vacation in the Philippines and a volcano blew..I was about 10 miles away..I couldn't belive how quickly the ash traveled..in a matter of minutes all the trees where gone and the sky dark..it was a nightemare. If I hadn't of been in a pretty secure building at the time, I dont think I would of made it...everything around us was pretty much history..
Topic 2 of 99 [Geo]: Vulcanism
Response 192 of 997: Maggie (sociolingo) * Sun, May 28, 2000 (06:00) * 1 lines
Mmm some story.
Topic 2 of 99 [Geo]: Vulcanism
Response 193 of 997: Marcia (MarciaH) * Sun, May 28, 2000 (15:07) * 1 lines
Indeed. I am trying to encourage him to login and post his experiences. He is a most fascinating individual, and I would like to get to know him better.
Topic 2 of 99 [Geo]: Vulcanism
Response 194 of 997: Marcia (MarciaH) * Sun, May 28, 2000 (18:14) * 15 lines
He sent this url, and lest it be thought that Hawaii has the only beautiful volcanoes, this one is the archetypal shape and displays why composite cones of mostly ash are so beautiful and so deadly:
Mayon Volcano: Cagsawa Church Ruins
Photograph by C.G. Newhall on September 23, 1984
Pyroclastic flows descend the south-eastern flank of Mayon Volcano, Philippines.
Maximum height of the eruption column was 15 km above sea level, and volcanic ash
fell within about 50 km toward the west. There were no casualties from the 1984
eruption because more than 73,000 people evacuated the danger zones as
recommended by scientists of the Philippine Institute of Volcanology and Seismology.
Topic 2 of 99 [Geo]: Vulcanism
Response 195 of 997: Marcia (MarciaH) * Sun, May 28, 2000 (18:47) * 5 lines
Thanks, Donn, for the urls and the great pictures.
If you'd like to see where I did my disaster relief work, please check
http://hvo.wr.usgs.gov/kilauea/history/1990Kalapana/
It was heart-breaking because all I could do was to hug them as they sobbed and watched their homes disappear - one after the other.
Topic 2 of 99 [Geo]: Vulcanism
Response 196 of 997: Marcia (MarciaH) * Sun, May 28, 2000 (18:49) * 1 lines
correcting my html problem...
Topic 2 of 99 [Geo]: Vulcanism
Response 197 of 997: Gi (patas) * Wed, May 31, 2000 (13:53) * 1 lines
Fantastic pics. Love the one with the smoke ring particularly.
Topic 2 of 99 [Geo]: Vulcanism
Response 198 of 997: Marcia (MarciaH) * Wed, May 31, 2000 (16:42) * 1 lines
Oh, You had not seen that? Incredible, no?!
Topic 2 of 99 [Geo]: Vulcanism
Response 199 of 997: Maggie (sociolingo) * Fri, Jun 2, 2000 (15:34) * 11 lines
CAMEROON: Mount Cameroon oozing lava
Lava has started to flow again from Mount Cameroon but government officials said on state radio there was no immediate cause for alarm, news organisations reported on Wednesday.
It is unclear exactly when the volcano started to erupt, although
residents of Buea, the town closest to the volcano, said there were
light earth tremors on Monday and thick smoke and fire at the top of the
mountain, Reuters reported state radio as saying.
When Mount Cameroon last erupted, in March and April 1999, the authorities evacuated residents of villages around the volcano. It lies along a geological fault that includes Lakes Nyos, from which carbon dioxide emissions on 21 August 1986 killed 1,700 people.
Topic 2 of 99 [Geo]: Vulcanism
Response 200 of 997: Marcia (MarciaH) * Fri, Jun 2, 2000 (18:41) * 54 lines
frica's Mt. Cameroon has begun erupting again. Felt earthquakes were
noted on 29 May, and by 30 May the summit was erupting "fire". It is unclear as to the precise onset of the eruption, one report said eruptions began 20 May. Reports on 31 May indicate a 3 mi. long lava flow has formed while eruptions of incandescent material continue at the summit.
From: http://www.cnn.com/2000/WORLD/africa/05/30/bc.cameroon.volcano.reut/index.html
Mount Cameroon shows signs of fresh volcanic activity
May 30, 2000
Web posted at: 9:47 AM EDT (1347 GMT)
YAOUNDE, Cameroon (Reuters) -- Mount Cameroon has shown signs of fresh
activity and people living near the volcano have been put on a state of
maximum alert, state radio reported on Tuesday.
The radio said residents of Buea in south-western Cameroon reported
light earth tremors on Monday and a cloud of thick smoke and fire at the top of the 4,095-meter high (13,435 feet) mountain.
Mount Cameroon sits on a seismic fault line that crosses the country.
The volcano was last active in March and April, 1999, when lava cut a
key highway before stopping a few meters (yards) from the Atlantic Ocean.
A government monitoring station is due to go into service in June at
Ekona, north of Buea, to provide early warning of any volcanic activity or
eruption
From:
http://www.cameroonnews.com/?action=display&article=2187152&template=dou
ala/stories.txt&index=recent
Lava Gushes Out of Mount Cameroon
The Associated Press, Wed 31 May 2000
YAOUNDE, Cameroon (AP) - Lava is gushing out of the Mount Cameroon
volcano in this central African nation, state-run radio reported Wednesday.
The hot, molten stream had extended up to three miles, the radio said.
The volcano, 195 miles southwest of the capital, Yaounde, began erupting on
May 20.
Government officials, however, said there was no immediate cause for
alarm.
``There is intense volcanic activity at the top of the mountain, which is essentially characterized by flames and a small flow of lava, which is still not very important,'' said Henri Hogbe Nlend, minister for
scientific and technical research, who surveyed the volcano from a helicopter.
The flames and lava flow are also primarily on the less populated side
of the slope, he added.
It is the second time in just over a year that the volcano has erupted.
In March and April 1999, flowing lava displaced thousands of people and
destroyed farmland.
Topic 2 of 99 [Geo]: Vulcanism
Response 201 of 997: Marcia (MarciaH) * Tue, Jun 6, 2000 (20:40) * 25 lines
http://www.lineone.net/cgi-bin/loadcontent.pl?page=/cgi-bin/drecgi/express/00/06/06/news/n0320-d.html
Maggie, You did it again! Sounds very exciting...!
Flash, bang, wallop, what a picture, what a photograph
BY LOUISE JONES
ALL they wanted was a quiet stroll up Mount Etna to gaze at one of the wonders of the world.
What they got was a sudden eruption, a half-mile run for their lives - and some great pictures to stick in the family album.
The 16 British holidaymakers were within 300 yards of the main crater of Europe's most-active volcano when lumps of molten rock started pouring down the mountainside.
The eruption began at 10.15am and it seemed such fun that geography teacher Lucy Newstead felt confident enough to pose smiling for a photograph.
But at 10.16am all hell broke loose. The party's Italian tour guides screamed at them to "run, run" as the volcano threatened to engulf them in a flow of boiling lava.
Lucy, 31, who teaches at Diss High School, Norfolk, said: "Suddenly there was an explosion of ash. Straight away we could see this lava fountain of red hot rock.
"It just got bigger and bigger and then lava bombs started flying through the air. It was an incredibly awesome sight and it all seemed to happen in slow motion.
"We started running over the ash and ice until we reached a path. Every time I stopped because I was out of breath they made me carry on.
"Some people were terrified, but I don't remember being scared. I did not even think about what danger we were in until we had reached safety."
She was on the adventure holiday with Explore Worldwide when she took pictures of the group's escape.
"I am just delighted to be here. It could have been a very different story if we had been closer to the crater when it erupted," she said.
The eruption was the volcano's most violent this year and could be seen for miles.
Fellow hiker Pat Holding, 52, of Sutton Coldfield, West Midlands, said: "It blew with no warning whatsoever. We saw a big white puff to begin with and then it darkened immediately and got higher and higher.
"Every time I looked behind me the mushroom cloud was getting bigger and bigger."
Mrs Holding, also a geography teacher, added: "There was no time to be scared. We just had to run for our lives. We went on the holiday in the first place to look at volcanos, but we ended up with a bit more than we bargained for."
The group had driven up the mountainside in a four-wheel drive vehicle before climbing to the 11,000 ft high summit.
They had earlier visited the Sicilian volcanoes Stromboli and Vulcano on their £600-a-head holiday.
Travers Cox, managing director of Explore Worldwide, said: "We have been running trips to Etna for six years without any problems. A lot of our groups are disappointed if they do not see an active volcano so these people are lucky in a way."Our tour guides are very experienced and we try not to put people in any danger."
© Express Newspapers, 2000
Topic 2 of 99 [Geo]: Vulcanism
Response 202 of 997: Marcia (MarciaH) * Tue, Jun 13, 2000 (13:29) * 22 lines
Subject: Rise in underground temperature
Dear Sir/Madame,
I am writting on behalf of a geologist here in Tashkent (Capital City of)
Uzbekistan.
They have a new puzzle which they are trying to find some answers for,
through anyone & everyone who is a specialist, in geological & ecological
problems.
Here in various locations around Tashkent city, at a depth of around 10
meters, the ground temperature has risen from around the normal readings of
aprox. 15 Celsius, up to as high as 30 & 50 Celsius!
The questions are, what is causing such an increase in heat of the
underground temperature around Tashkent, & have other major cities of the
world has such cases of such readings?
Thanks for any help, & correspondance in this matter.
Joe Ruuskanen
(Humanitarian aid worker for Central Asian Free Exchange, Tashkent
Uzbekistan)
Topic 2 of 99 [Geo]: Vulcanism
Response 203 of 997: anne hale (ommin) * Wed, Jun 14, 2000 (06:15) * 1 lines
HOW STRANGE WHAT ON EARTH DOES IT MEAN? It sounds rather worrying to me. Can anyone confirm the meaning.
Topic 2 of 99 [Geo]: Vulcanism
Response 204 of 997: Curious Wolfie (wolf) * Wed, Jun 14, 2000 (08:27) * 1 lines
do they sit on a fault-line or volcanic area? wouldn't magma rising slowly to the surface cause the heat to increase? (oh, we're supposed to give answers not more questions!!)
Topic 2 of 99 [Geo]: Vulcanism
Response 205 of 997: Marcia (MarciaH) * Wed, Jun 14, 2000 (11:55) * 1 lines
I post questions as well as answers. If we had all the answers, there would be no purpose for Geo other than playing. hmmmm..that's what we do anyway. Get back to you on that question - gotta consult my experts!
Topic 2 of 99 [Geo]: Vulcanism
Response 206 of 997: Curious Wolfie (wolf) * Wed, Jun 14, 2000 (12:26) * 2 lines
oh, look, marcia has her own experts! *giggle* please let us know, this is most curious.
Topic 2 of 99 [Geo]: Vulcanism
Response 207 of 997: Marcia (MarciaH) * Wed, Jun 14, 2000 (23:38) * 1 lines
How about Funk and Wagnals?? Now you haave made me forget the question Yup, the family geologist/volcanologist... Wolfie, behave.....I thought you were my friend....*sigh* Google.com is my expert if all else fails...
Topic 2 of 99 [Geo]: Vulcanism
Response 208 of 997: Marcia (MarciaH) * Wed, Jun 14, 2000 (23:54) * 1 lines
Back from reading that post about the rise in temperatures of the ground in and around Tashkent...That was forwarded to me by son David who got it from a bulletin sent out to professional geologists and volcanologists. Apparently no one knows and they are asking for help. Will let you know further when I know.
Topic 2 of 99 [Geo]: Vulcanism
Response 209 of 997: Marcia (MarciaH) * Tue, Jun 20, 2000 (23:19) * 37 lines
Montserrat Volcano Observatory - Montserrat, W.I.
Report for the period midday, 9 June 2000 to midday, 16 June 2000
Rockfalls and small pyroclastic flows have occurred from the growing lava
dome throughout the week, with a dilute ash plume maintained to the west of
the island.
The broadband seismic network recorded a total of 326 rockfall signals, 49
hybrid earthquakes, 1 volcano-tectonic and 76 long period earthquakes for
the reporting period. There has been a marked increase in rockfall activity
this week and a sustained high level of long-period earthquakes. This
information suggests that the dome is still growing at a moderate rate.
Visual observations of the Soufrière Hills Volcano have again been hampered
throughout the week by low cloud. The upper parts of the dome were glimpsed
briefly early in the week. The high point on the dome is now close to 3,000
ft, and the size of the dome is approaching the same as it was immediately
prior to the large collapse event of 20 March 2000. Rockfall and
pyroclastic flow activity has been in the Tar River valley and within the
summit crater. There has been steady production of volcanic ash which has
blown westwards over Plymouth and out to sea; ash has not affected inhabited
areas.
The GPS network is fully operational, and the pattern of ground deformation
remains similar to that which has been seen since late last year.
Maintenance of field stations is still being hampered by the dry, ashy
conditions on the volcano.
Residents of and visitors to Montserrat are advised to tune in to ZJB Radio
for up-to-date information on the status of the volcano. Rockfall and
pyroclastic flow activity is likely to remain at a high level for several
weeks, producing more ash clouds which may blow over inhabited areas if
winds are from the south or southeast. Elevated levels of pyroclastic flow
activity may develop very rapidly. Ash masks should be worn in ashy
conditions or when you disturb ash. The Belham valley should be avoided
during and after periods of heavy rain and everyone is reminded that access
to Plymouth, Bramble airport and beyond is prohibited.
Topic 2 of 99 [Geo]: Vulcanism
Response 210 of 997: Marcia (MarciaH) * Tue, Jun 20, 2000 (23:20) * 20 lines
Mount Cameroon volcano lava threat recedes
June 14, 2000
Web posted at: 11:20 AM EDT (1520 GMT)
YAOUNDE, Cameroon (Reuters) -- Lava flowing down the flanks of Mount
Cameroon has slowed and the threat to people in the nearby town and
villages has receded, officials said on Wednesday.
"There is no more reason to panic. All is calm and the people are going
about their jobs normally," an aide to the governor of South West Province
in the town of Buea told Reuters by telephone on Wednesday.
Scientists monitoring the volcano, which showed fresh signs of activity on
May 29 and later began spewing lava, said last week that Buea was a high
risk zone and the authorities were on standby to evacuate people living in
the area.
The 4,095 meter (13,435 foot) volcano is on a geological fault line running
through Cameroon. It was last active in March and April, 1999, when lava
cut a key highway before stopping a few meters from the Atlantic Ocean.
Topic 2 of 99 [Geo]: Vulcanism
Response 211 of 997: Marcia (MarciaH) * Sun, Jun 25, 2000 (16:14) * 32 lines
For the European contingent, You have volcanoes too:
**************************************
Piton de la Fournaise - new eruption
**************************************
From: Dan Shackelford
Increased seismicity on 22 June and at ~1800 on 23 June a new eruption
began at Piton de la Fournaise, on the SE flank of Dolomieu. Bad weather
has precluded visual observations to date.
Following from Henry Gaudru
SVE INFORMATION release - June 24, 2000
PITON DE LA FOURNAISE - Reunion Island - (France)
Following an increasing of the seismic activity during Thursday 22nd a new
eruptive activity has began on the Piton de la Fournaise. From a local
source the new eruption occured on Friday 23 at 6 PM (local time).
Preliminary information shows that the eruption started from the Southeast
flanc of the Dolomieu crater (Summit of the Piton de la Fournaise) near the
site of the previous eruption of July 1999. Because poor meteorological
condition no direct observation was possible yesterday. (Further details next )
----------------------------------
European Volcanological Society
C.P.1 - 1211 Geneva 17
Switzerland
Fax : 41.22.759.21.05
Email : info@sveurop.org
http://www.sveurop.org
Topic 2 of 99 [Geo]: Vulcanism
Response 212 of 997: Marcia (MarciaH) * Sun, Jul 2, 2000 (20:26) * 33 lines
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 23 June 2000 to midday, 30 June 2000
Activity has increased at the Soufrière Hills Volcano this week, with almost
continuous rockfall activity and small pyroclastic flows being produced.
The broadband seismic network recorded a total of 315 rockfall signals, 4
hybrid earthquakes, 4 volcano-tectonic and 157 long period earthquakes for
the reporting period. The number and size of rockfall events increased
throughout the week. Long-period earthquake activity remains at a high
level, indicating relatively high pressures inside the dome.
Dome growth is occurring high on the eastern face of the dome at the top of
the Tar River Valley, forming a rough spiny area. Much of this material is
cascading down the steep eastern face of the dome producing many small
rockfalls and small pyroclastic flows. Rockfall talus is accumulating more
slowly around the southern edge of the dome, where it encroaches on a low
point which would lead into White River Valley. Good views of the notches
onto the north flanks of the volcano and into Gages Valley were not
obtained. Although the volcano appears to be quiet, the level of activity
can change extremely quickly and portions of the dome can collapse with no
warning and generate much larger pyroclastic flows than have been seen for
many months.
Residents of and visitors to Montserrat are advised to tune in to ZJB Radio
for up-to-date information on the status of the volcano. Rockfall and
pyroclastic flow activity is likely to remain at a high level for several
weeks, producing more ash clouds which may blow over inhabited areas if
winds are from the south or southeast. Elevated levels of pyroclastic flow
activity may develop very rapidly and could affect any valleys around the
volcano. Ash masks should be worn in ashy conditions or when you disturb
ash. The Belham valley should be avoided during and after periods of heavy
rain and everyone is reminded that access to Plymouth, Bramble airport and
beyond is prohibited. The daytime entry zone remains closed.
12 noon, Friday, 30 June 2000
Topic 2 of 99 [Geo]: Vulcanism
Response 213 of 997: Marcia (MarciaH) * Mon, Jul 10, 2000 (22:06) * 5 lines
Kilauea is not doing this right now, but in honor of Geo's Birthday....
Topic 2 of 99 [Geo]: Vulcanism
Response 214 of 997: Ginny (vibrown) * Mon, Jul 10, 2000 (23:45) * 1 lines
Love that last photo! When was that one taken? Kilauea did not do that when I was there...which is probably a good thing, considering where we were hiking... :-)
Topic 2 of 99 [Geo]: Vulcanism
Response 215 of 997: Marcia (MarciaH) * Tue, Jul 11, 2000 (00:05) * 2 lines
My thoughts exactly... we would have had to have the old asbestos umbrella handy. It was during this episode that the fountain reached 2000' (610M) and made a roar heard 10 miles away. I did not get up there to see it, and that phase did not last very long, but it WAS spectacular! I'll have to check with David and see if he can remember when it occurred. I can't seem to remember.
The lable on the image was just "gyser"(sic)
Topic 2 of 99 [Geo]: Vulcanism
Response 216 of 997: Maggie (sociolingo) * Fri, Jul 14, 2000 (05:16) * 35 lines
Friday July 14, 9:32 AM
Japan volcano erupts again on island off Tokyo
TOKYO (Reuters) - A Japanese volcano erupted for a second time on Friday, spewing ash and rocks high into the air and prompting officials to recommend the evacuation of residents, officials said.
A local government official said the eruptions were expected to be short-lived and were unlikely to pose threat to the nearly 4,000 inhabitants of the island.
However, they recommended the evacuation of residents of about 30 homes near the foot of Mount Oyama on the island of Miyakejima, some 200 km (125 miles) south of Tokyo, as large amounts of ash cascaded from the sky after the eruption.
"It's a pretty impressive cloud of ash, so we decided to issue the evacuation warning," a Miyakejima official said. "We will monitor the situation closely."
A Meteorological Agency official said Friday's second eruption from the summit of Mount Oyama took place at 3:50 p.m. (7.50 a.m.).
"The eruptions are within our expectations and unless there are other signs, we don't think there will be a major eruption," the official said.
There were no immediate reports of injuries or damage.
BILLOWING GRAY ASH
Like the first eruption earlier in the day, pale gray ash was seen being billowing about 1,000 metres into the air after a thunderous explosion from the volcano's summit.
Last Saturday, a similar eruption occurred at Mount Oyama, hurling ash and rocks into the air.
The volcano started to rumble at the end of June, but residents who had been evacuated from homes near the mountain were given the green light to return home after a few nights in local schools and other designated evacuation centres.
The island chain south of Tokyo has experienced tens of thousands of earthquakes over the past few weeks triggered by the increasingly active volcano.
This month, a powerful earthquake rocked the neighbouring island of Kozushima, triggering landslides that killed one man, the first earthquake fatality in the earthquake-prone nation for five years.
Miyakejima is one of a chain of seven islands south of Tokyo.
The island has a population of about 3,800 and its perimeter measures about 38 km (22 miles).
Mount Oyama's last major eruption was in 1983 when it destroyed 400 houses and left a moonscape of rock, burning out nearby forests and destroying a lake. A lava flow from an eruption in 1940 killed 11 people and it erupted again in 1962.
Topic 2 of 99 [Geo]: Vulcanism
Response 217 of 997: Maggie (sociolingo) * Fri, Jul 14, 2000 (05:16) * 1 lines
(loved the picture Marcia)
Topic 2 of 99 [Geo]: Vulcanism
Response 218 of 997: Marcia (MarciaH) * Fri, Jul 14, 2000 (12:41) * 1 lines
(Thanks, Maggie!) The photos and video on the morning news were truly horrifying. Thanks for posting the article!
Topic 2 of 99 [Geo]: Vulcanism
Response 219 of 997: Marcia (MarciaH) * Fri, Jul 14, 2000 (20:25) * 36 lines
Friday July 14 4:38 AM ET
Japan Volcano Erupts Again on Island Off Tokyo
TOKYO (Reuters) - A Japanese volcano erupted for a second time
on Friday, spewing ash and rocks high into the air and prompting
officials to recommend the evacuation of residents, officials said.
A local government official said the eruptions were expected to be
short-lived and were unlikely to pose threat to the nearly 4,000 inhabitants of the island.
However, they recommended the evacuation of residents of about 30 homes near the foot of
Mount Oyama on the island of Miyakejima, some 125 miles south of Tokyo, as large amounts of
ash cascaded from the sky after the eruption.
``It's a pretty impressive cloud of ash, so we decided to issue the evacuation warning,'' a
Miyakejima official said. ``We will monitor the situation closely.''
A Meteorological Agency official said Friday's second eruption from the summit of Mount Oyama
took place at 3:50 p.m.
``The eruptions are within our expectations and unless there are other signs, we don't think there
will be a major eruption,'' the official said.
There were no immediate reports of injuries or damage.
Billowing Gray Ash
Like the first eruption earlier in the day, pale gray ash was seen being billowing about 1,000
meters into the air after a thunderous explosion from the volcano's summit.
Last Saturday, a similar eruption occurred at Mount Oyama, hurling ash and rocks into the air.
The volcano started to rumble at the end of June, but residents who had been evacuated from
homes near the mountain were given the green light to return home after a few nights in local
schools and other designated evacuation centers.
The island chain south of Tokyo has experienced tens of thousands of earthquakes over the past
few weeks triggered by the increasingly active volcano.
This month, a powerful earthquake rocked the neighboring island of Kozushima, triggering
landslides that killed one man, the first earthquake fatality in the earthquake-prone nation for five
years.
Miyakejima is one of a chain of seven islands south of Tokyo.
The island has a population of about 3,800 and its perimeter measures about 22 miles.
Mount Oyama's last major eruption was in 1983 when it destroyed 400 houses and left a
moonscape of rock, burning out nearby forests and destroying a lake. A lava flow from an eruption
in 1940 killed 11 people and it erupted again in 1962.
Topic 2 of 99 [Geo]: Vulcanism
Response 220 of 997: Maggie (sociolingo) * Sat, Jul 15, 2000 (03:52) * 1 lines
(Hey, I just posted that - see 216!!! Great minds or somthing....)
Topic 2 of 99 [Geo]: Vulcanism
Response 221 of 997: Marcia (MarciaH) * Thu, Jul 20, 2000 (22:46) * 34 lines
Date: Thu, 20 Jul 2000 12:24:23 -0700
From: Barry Cameron
Subject: Eruption at Lascar, Chile
Sender: VOLCANO
Approved-by: Barry Cameron
To: VOLCANO@asu.edu
Reply-to: VOLCANO
X-Mailer: Internet Mail Service (5.5.2650.21)
*******************
Eruption at Lascar, Chile
July 20, 2000
*******************
The Washington Volcanic Ash Advisory Center has been notified of a major
eruption of Lascar in eastern Chile. GOES-8 satellite imagery confirmed the
eruption at approximately 14:10 UTC. The cloud, estimated at 35 to 40
thousand feet, is presently moving east into northern Argentina. Official
advisories will be issued by the Buenos Aires Volcanic Ash Advisory Center.
Satellite imagery including still images and loops can be viewed at the
NOAA Satellite Services Division website, at:
http://www.ssd.noaa.gov/SAB/cases.html
Brian Hughes
Meteorologist
NOAA/NESDIS Satellite Analysis Branch
Washington Volcanic Ash Advisory Center
Topic 2 of 99 [Geo]: Vulcanism
Response 222 of 997: Marcia (MarciaH) * Wed, Aug 2, 2000 (16:14) * 25 lines
Can't wait to read the papers coming out of this conference since I also live on an active volcano!
**************************************
Cities on Volcanoes-2
Auckland, New Zealand
February 12-16, 2001
Auckland is a modern vibrant city, with an international status in trade,
investment and business, superbly located on a green isthmus between two
magnificent harbours. However the metropolitan centre of Auckland has
developed across a potentially active basaltic volcanic field. It also faces
a hazard from several large central North Island volcanic centres. Auckland,
like many other cities, is preparing for a volcanic crisis through
collaborative work of specialists in a variety of fields, such as
volcanology, sociology, psychology, emergency management, economics and
city planning.
This meeting will provide a forum for specialists from several disciplines
and countries to collaborate to re-evaluate volcanic crises preparedness and
management in cities and densely populated areas. By drawing upon
multidisciplinary perspectives the workshop affords an opportunity to develop
strategies and consider the means for their implementation.
Topic 2 of 99 [Geo]: Vulcanism
Response 223 of 997: Marcia (MarciaH) * Wed, Aug 2, 2000 (16:38) * 33 lines
***********************
Eruption at Semeru, Indonesia
July 27, 2000
***********************
We sadly post this report:
At approximately 0621 on the morning of 27 July an eruption from the summit
crater of Semeru resulted in two deaths and injuries to six other
volcanologists near the crater. Both fatalities, Wildan and Mukti, were
Indonesian scientists from the Volcanological Survey of Indonesia (VSI).
Other members of the group sustained injuries caused by ejected material.
These included Kris from VSI, Amit Mushkin from the Hebrew University in
Israel, Mike Ramsey from the University of Pittsburgh, and Lee Siebert and
Paul Kimberly from the Smithsonian Institution. Kimberly's injuries were
more serious, including a broken hand, broken arm, and 3rd-degree burns. He
is now recovering in a Singapore hospital.
The members of the group had attended a meeting of the International
Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI)
in Bali during the previous week.
Background. Semeru, the highest volcano on Java, and one of its most
active, lies at the southern end of a volcanic massif extending north to
the Tengger caldera. The steepsided volcano, also referred to as Mahameru
(Great Mountain), rises abruptly to 3676 m elevation, towering above
coastal plains to the south. Gunung Semeru was constructed south of the
overlapping Ajekajek and Jambangan calderas. A line of lake-filled maars was
constructed along a NS trend cutting through the summit, and cinder cones
and lava domes occupy the eastern and NE flanks. Summit topography is
complicated by the shifting of craters from NW to SE. Frequent 19th and
20th century eruptions were dominated by small to moderate explosions from
the summit crater, with occasional lava flows and larger explosive
eruptions accompanied by pyroclastic flows that have reached the lower
flanks of the volcano. Semeru has been in almost continuous eruption since 1967.
Topic 2 of 99 [Geo]: Vulcanism
Response 224 of 997: Marcia (MarciaH) * Wed, Aug 2, 2000 (16:38) * 9 lines
************************
Lascar Eruption Images - July 20, 2000
************************
This kindly submitted by Dr. Jose Viramonte:
GOES 8 and NOAA 14 images of the Lascar eruption on
07/20/00 can be found at:
http://www.unsa.edu.ar/varias/lascar/
Topic 2 of 99 [Geo]: Vulcanism
Response 225 of 997: Marcia (MarciaH) * Thu, Aug 10, 2000 (20:43) * 35 lines
**************************************
Mount Oyama, Miyakejima, Japan
**************************************
http://dailynews.yahoo.com/h/nm/20000810/sc/japan_volcano_dc_3.html
Thursday August 10 2:37 AM ET
Japan Volcano Erupts Again on Island Off Tokyo
TOKYO (Reuters) - A volcano on a small Japanese island south of Tokyo
erupted again early Thursday, spewing steam, smoke and ash into the air,
and prompting local officials to urge nearby residents to evacuate.
The eruption from the summit of Mount Oyama on the island of Miyakejima,
some 113 miles south of Tokyo, took place at 6:59 a.m. (5:59 p.m. EDT
Wednesday), the Meteorological Agency said.
There were no reports of injuries or damage from the eruption. Some 4,000
people live on the small resort island.
The volcano has erupted several times since the end of June. It last
erupted on July 15.
Although the eruptions seemed to have subsided slightly, local officials
recommended the evacuation of some 630 residents from 315 homes near the
foot of the volcano.
"There has been no panic among the residents and the eruption is apparently
subsiding. But as a precaution, we have urged residents to evacuate," one
official said.
The eruption forced the airport on the island to close and commercial
flights between Tokyo and the island were canceled, an airport spokesman said.
The island chain south of Tokyo has experienced tens of thousands of
earthquakes in the past two months triggered by the increasingly active
volcano.
Mount Oyama's last major eruption was in 1983 when it destroyed 400 houses
and left a moonscape of rock, burning out nearby forests and destroying a
lake. A lava flow from an eruption in 1940 killed 11 people and it erupted
again in 1962.
Topic 2 of 99 [Geo]: Vulcanism
Response 226 of 997: Marcia (MarciaH) * Sun, Aug 20, 2000 (13:10) * 14 lines
**************************
Miyakejima eruption
**************************
Mount Oyama experienced its largest eruption in 17 years, forcing the
evacuation of residents. There were no reports of injuries, but some reports
said the ash had formed into a small rock-like objects that had fallen on to
car roofs. The volcano last erupted on August 10.
For full stories and links, see:
http://dailynews.yahoo.com/h/nm/20000818/sc/japan_volcano_dc_7.html
http://www.cnn.com/2000/ASIANOW/east/08/18/japan.volcano.reut/index.html
Topic 2 of 99 [Geo]: Vulcanism
Response 227 of 997: Marcia (MarciaH) * Mon, Aug 21, 2000 (00:52) * 40 lines
****************************************
Elevated seismicity at Bandaisan, Japan
****************************************
In 1888 a sector collapse at Japan's Bandaisan created a horseshoe-shaped
caldera open to the N and killing 461 people in the process. [There were
several explosions that may have triggered this event]. Some 1½ km3 of
debris deposits from the catastrophic slope failure.
Since Aug 14 there has been much elevated seismicity at this volcano,
including felt events and tremor. JMA began monitoring this volcano in 1965.
This information courtesy of:
http://hakone.eri.u-tokyo.ac.jp/vrc/erup/bandai.html
(maintained by S. Nakada of the University of Tokyo)
****************************************
White Island and Ruapehu, New Zealand
****************************************
For the week ending 18 August, White Island continued its mild gas and ash
venting unchanged, with plumes to ~1,000m. Ruapehu had an episode of moderate
to strong volcanic tremor without any visible change in its activity.
From:
http://www.gns.cri.nz/hazardwatch/latest/gweekvo.htm
White Island
Minor eruptive activity continued during the week. No notable changes in
activity occurred. Ash and gas plumes rose to a height of about 1000m and
drifted about 50 km downwind of the volcano. The Alert level remains at
2.
Ruapehu
A short period of moderate-strong volcanic tremor was recorded during the
week, but no volcanic activity was observed associated with this
tremor. Ruapehu remains at Alert Level 1 (signs of volcano unrest).
Topic 2 of 99 [Geo]: Vulcanism
Response 228 of 997: Marcia (MarciaH) * Tue, Aug 22, 2000 (23:22) * 26 lines
More info on Miyakejima, Japan
********************************
Following information from:
http://hakone.eri.u-tokyo.ac.jp/vrc/erup/miyake.html (maintained by S. Nakada)
Since the 8 July summit collapse opened a pit crater atop Miyakejima's
Oyama cone, collapse has continued, marked by ongoing deflation and
earthquakes. This now likely is a small caldera, currently 1.4km diam by
450m deep. Intermittent phreatic eruptions continue, especially since 10
August. Photos of the 10 and 14 August eruptions appear on the URL above.
Prior to 10 August, an est. 2 million cubic meters of ejecta while the
caldera vol. is about 0.35 cubic km. The eruption cloud on 10 Aug.
eventually achieved 10km in ht. A rather large eruption from ~1700 - ~1900
on 15 Aug. with the eruption cloud rising to at least 8km. "Abundant ash
fell mainly in the northwestern part of the volcano island; as thick as 15
cm about 3 km away from the crater. Cinders as large as 5 cm fell over the
airport which locates in the southeastern part of the island, breaking
windows of automobiles". All eruptions to date appear to solely phreatic in
nature, although the 18 Aug. tephra is still being analyzed.
**************************
Miyakejima, Japan photos
**************************
From: Claude Desgroseilliers
http://www3.50megs.com/claude/volcano/miyakejimavolcano.html --
Topic 2 of 99 [Geo]: Vulcanism
Response 229 of 997: Marcia (MarciaH) * Thu, Aug 24, 2000 (23:16) * 78 lines
I wish I could attend this:
*********************************
Penrose Conference Announcement
*********************************
Penrose Conference to address Longevity and Dynamics of Rhyolitic Magma
Systems
A Geological Society of America Penrose Conference, "Longevity and Dynamics
of Rhyolitic Magma Systems" will be held June 7-12, 2001, in Mammoth,
California. Mammoth Mountain forms the southwest rim of the Long Valley
caldera, one of three large Quaternary rhyolitic caldera centers in the
United States. Long Valley, a site of recent volcanic unrest, lies at the
heart of current debate over the mechanisms and time scales for the
production, storage, and differentiation of rhyolite magma. Such
information is critical to our understanding of fundamental geologic
problems such as the formation and growth of Earth's continents and
predicting volcanic hazards.
The purpose of the conference is to bring together petrologists,
geochemists, volcanologists and geophysicists actively studying the
generation and evolution of silicic magmas. We hope to try and resolve, or
at least constrain, a number of very important and currently highly topical
issues pertaining to the shallow-crustal evolution of large, typically
caldera-forming, silicic magma bodies. These include:
… What is a magma chamber-a large, long-lived fractionating liquid body or
a "sleepy" crystal mush that gets kicked to life every so often,
re-mobilizing existing material? A related issue is to what degree do
plutons carry-forward, in some integrated way, the expression of this?
… What do crystals really represent-phenocrysts vs. xenocrysts-and what
'memory' do they retain? Related to this issue are questions such as does
crystal growth- and dissolution-zoning reflect protracted fractionation of
a single magma body or remobilization and dispersal of crystal mush during
injection of fresh magma into the subvolcanic system and how do crystals
move in the magma system - or are the crystals effectively static in a
moving magma system?
… What is the efficacy of, and driving forces for, convection/mixing in
silicic magmas? Can crystal disequilibrium features, such as
chemical/isotopic zoning and dissolution surfaces, serve to discriminate
between thermal convection and magma mixing?
… What are the time scales needed to produce large, rhyolitic magma bodies?
Recent work using 40Ar/39Ar, Rb/Sr or U-series isotope data has led to the
suggestion that rhyolite magmas in the Long Valley system are stored,
following differentiation, for long (105-106) time scales. This contention
has been disputed principally on the basis that it would be difficult to
keep a body of magma thermally viable for such long periods, even if
grater than 500km3 volume. Alternative physical models have been proposed, such as
remobilization of juvenile plutons or cumulate materials and ion microprobe
work on zircons has variously upheld or contested the claims for long magma
residence times. A key focus of the meeting will be to evaluate the
different types of data available that bear on ages of magmatic events, and
discuss their interpretations.
A limited number of keynote talks will serve to outline the current state
of knowledge concerning the generation and evolution of large rhyolitic
magma systems, and will set the foundation for evaluation of existing
paradigms, development of new models, and discussion of future research
directions. Most of the meeting will focus on poster sessions and group
discussions. Mid-meeting field trips to selected Bishop Tuff and Sierran
plutonic locations will serve to raise questions concerning limits and
constraints on sampling and interpreting geochemical data from pyroclastic
deposits based on our knowledge of how large silicic systems erupt, links
between plutonic and volcanic environments, and the importance of recharge
and mixing in magma evolution.
The conference is limited to approximately 50 participants to ensure a
'workshop-type' atmosphere focussed on manageable discussions. We
encourage participation of graduate students working on silicic magma
systems; partial student subsidies will be available. The registration
fee, which will include lodging, some meals, field trips, and all other
conference costs except personal incidentals, is not expected to exceed
$750. Information on travel to the conference will be provided in the
letter of invitation.
Topic 2 of 99 [Geo]: Vulcanism
Response 230 of 997: Marcia (MarciaH) * Thu, Aug 24, 2000 (23:17) * 10 lines
Arenal, Costa Rica
Arenal Volcano erupted yesterday, Wednesday, Aug. 23, injuring two American
tourists and a Costan Rican tour guide hiking near the volcano. The tour
guide, Ignacio Protti, later died from second and third degree burns.
From:
http://www.nacion.co.cr/ln_ee/2000/agosto/24/pais1.html (in Spanish)
http://dailynews.yahoo.com/h/p/ap/20000824/wl/costa_rica_volcano_cof.html
Topic 2 of 99 [Geo]: Vulcanism
Response 231 of 997: Marcia (MarciaH) * Fri, Aug 25, 2000 (16:07) * 28 lines
From Maggie and Reuters: Friday August 25 12:54 AM ET
Japan Volcano-Hit Island Set to Evacuate Children
TOKYO (Reuters) - Japanese authorities plan to evacuate nearly 200 school children from an island near Tokyo after a volcanic eruption last week left the island covered in ash and fearful of more eruptions.
Officials on Miyakejima island, struck by its biggest eruption in 17 years on August 18, said the evacuation may occur within a week to have the children settled by September 1, the start of the new school term.
This would involve taking around 190 primary and junior high school children off the island, by ship, to an evacuation site somewhere in the Tokyo metropolitan area, they added.
``Authorities are saying there could be another eruption like the one last week, or even larger,'' said Chihoko Kaechi, an official at the Miyakejima Board of Education. ``We can't guarantee the children's safety.''
The total population of primary and junior high students is 327, but the rest have already left voluntarily.
A week ago, the island was plunged into darkness when a massive pall of smoke and ash from Mount Oyama was thrown as high as 26,400 feet into the air, burying the island in centimeters of gray ash.
The volcano has erupted repeatedly since late June. It spat out more ash Friday morning.
``This place is like a desert now,'' said Kaechi. ``It's very hot and the ash gets in your eyes. People with conditions like asthma are really suffering.''
Workers have been clearing the ash from roads and buildings, using shovels and brooms and scooping it into bags.
The Meteorological Agency has warned that, while they believe it unlikely, they cannot entirely rule out an eruption of magma at some point. Eruptions on the scale of the August 18 eruption, or larger, are also possible, with the chance of small rocks being thrown out with the ash.
Decision To Be Made Soon
Tokyo government officials said that while no final decision on the evacuation had yet been made, they expected one soon.
``The biggest difficulty is deciding whether to keep each school together or break them into smaller units and evacuate them separately,'' an official with the Tokyo Board of Education said. ``And of course it is quite hard to find a good site.''
About 4,000 people live on Miyakejima, 113 miles south of Tokyo, part of the Izu island chain, which has been jolted by tens of thousands of earthquakes in addition to volcanic eruptions over the past two months.
Some 800 have already left the island voluntarily. Those who remained have suffered through periodic orders for short-term evacuations to gymnasiums and public halls.
Mount Oyama's last major eruption in 1983 destroyed 400 houses and left a moonscape of rock, burning out nearby forests and destroying a lake. A lava flow from an eruption in 1940 killed eleven people.
Japanese media reported that Miyakejima's mayor had asked that all remaining residents be evacuated from the island, but a Tokyo city official said there had been no formal request.
The entire population of Oshima, another island in the chain, was evacuated when a volcano there erupted in 1986.
The Tokyo official said that the city was not considering such an evacuation at this point, adding that it was not yet dangerous enough to warrant the logistical difficulties and the trauma involved in uprooting people from their homes.
``Besides, the activity of this volcano is proving extremely difficult to predict. Who will take responsibility for evacuating people -- and then nothing happens for months or years?''
Topic 2 of 99 [Geo]: Vulcanism
Response 232 of 997: Marcia (MarciaH) * Fri, Aug 25, 2000 (20:16) * 13 lines
This web site contains the updating Etna, Vesuvius and Stromboli Volcanoes. Watch them erupt!
*******************************************
Earthquakes & Volcanoes in Sicily website
*******************************************
From: Villari Letterio
I should like to inform the Volcano List Server follower that since the
beginning of the current year weekly news on Earthquakes and Volcanoes in
Sicily (Italy) are available, on-line, by consulting the Poseidon web page,
at http://www.poseidon.nti.it address.
L. Villari, Director
Topic 2 of 99 [Geo]: Vulcanism
Response 233 of 997: Marcia (MarciaH) * Sun, Aug 27, 2000 (14:25) * 3 lines
Mt Etna is erupting and may get a lot bigger. Watch in real time:
http://www-personal.usyd.edu.au/~gerhard/cam_etna.html
Topic 2 of 99 [Geo]: Vulcanism
Response 234 of 997: Marcia (MarciaH) * Mon, Aug 28, 2000 (23:46) * 19 lines
"Today In Volcanic History"
This is for all of August-
August 4 1905- Savai'i, Samoa Erupts
August 8 1991- Hudson, Chile Erupts
August 16 1663- Usu, Japan Erupts
August 17 915- Towada, Japan Erupts
August 24 79- Vesuvius, Italy Erupts
I snitched this from
Yahoo! Clubs: WARNING Volcanology Activated
Topic 2 of 99 [Geo]: Vulcanism
Response 235 of 997: Maggie (sociolingo) * Tue, Aug 29, 2000 (03:09) * 21 lines
Update on the Japanese volcano:
Tuesday August 29 2:39 AM ET
Japan Island Volcano Erupts; Evacuation Speeded Up
By Elaine Lies
TOKYO (Reuters) - A volcano on a Japanese island 113 miles south of Tokyo spewed a huge column of steam, smoke and ash Tuesday, forcing authorities to speed up a planned evacuation of school children from the island. Officials on Miyakejima said they were taking the last remaining school children off the island Tuesday afternoon rather than Thursday, as previously scheduled.``This new eruption made us decide to speed up the evacuation as it's no longer safe,'' a Board of Education official said. Some 139 children, from primary to high school, were scheduled to leave by boat later Tuesday. There are normally close to 500 students on the island, but the rest had already left voluntarily.
Authorities were hurrying to take enough food and bedding to a boarding school in western Tokyo where the students will be housed, NHK public television said.
The evacuation will last at least until the end of September.
Television pictures showed Miyakejima island shadowed by a massive pall of smoke and ash that shot as high as 26,400 feet into the air from Mount Oyama.
Officials said the eruption -- the ninth in a series that began in late June -- emitted no volcanic cinders, unlike an eruption on August 18 that was the largest in 17 years, but warned that the situation remained extremely fluid.
``There is a strong smell of sulphur in the air, but this eruption is much smaller than the one two weeks ago,'' an official at the Miyakejima town office said.There was no outflow of lava but up to six inches of ash had accumulated on some parts of the island.
Emergency Task Force
Residents were told to stay indoors while officials prepared evacuation centers for residents who wanted to leave their homes.No formal evacuation order had been issued, however, and there were no reports of injuries.Chief cabinet secretary Hidenao Nakagawa told a regular news conference Tuesday the government was establishing an emergency task force to aid evacuation efforts and address safety issues.About 4,000 residents live on Miyakejima, part of the Izu island chain that has been jolted by tens of thousands of earthquakes in addition to volcanic eruptions over the past two months.The nearby islands of Niijima and Kozushima were jolted by a moderately strong earthquake that measured 5.0 on the Richter scale Tuesday morning, but there were no reports of damage or tidal waves.Around 1,159 people had left Miyakejima as of late Monday, Japanese media said -- more than one-third of the population.The Meteorological Agency has warned it cannot entirely rule out the possibility of an eruption of magma, althoug
this is considered unlikely. Eruptions on the scale of the August 18 eruption or larger are also possible, with the chance of small rocks spewing out with the ash.
Mount Oyama's last major eruption in 1983 destroyed 400 houses and left a moonscape of rock, burning out nearby forests and destroying a lake. A lava flow from an eruption in 1940 killed 11 people.The latest eruption also briefly appeared to boost sulphur dioxide levels to several times acceptable amounts in the air over areas west and south of Tokyo, where residents complained of a sulphurous smell Monday. No illnesses were reported.Prevailing winds apparently blew smoke from Miyakejima toward the area, Japanese media reported.
Topic 2 of 99 [Geo]: Vulcanism
Response 236 of 997: Marcia (MarciaH) * Tue, Aug 29, 2000 (13:08) * 1 lines
Thank, Maggie. David has not sent me the official update yet!
Topic 2 of 99 [Geo]: Vulcanism
Response 237 of 997: Marcia (MarciaH) * Tue, Aug 29, 2000 (23:59) * 38 lines
***********************
Arenal, Costa Rica
***********************
Last Wednesday 23 of August, Arenal Volcano, Costa Rica, erupted a sequence
of pyroclastic flows originated by a crater collapse in the north flank of
the volcano.
The first activity began at 15:45 hours GMT, with a vigorous emission that
began at 16:01 and had a duration of 23 minutes. Two tourists and their
guide were burnt by the front part of the flow, about 2.3 km. from the
crater. The guide Ignacio Protti took the two tourists, walking about 500m.
and driving about 2 km to a safer place. Mr. Protti died around midnight
(6:00 GMT of Aug. 24).
A second and more intense sequence of flows began at 19:23 GMT with a
duration of 1 hour and 14 min.
The deposits reached a maximum distance of 2.7 km. from the active crater
and expanded more than 300 m in the distal part.
The following activity has returned to the normal emission of gases
(carried to the west by the predominant winds) and lava through the same
direction of the pyroclastic flows.
The National Park was closed and most of the nearest hotels were evacuated.
On Saturday 26 an airplane with 10 passengers crashed against the
northeastern flank of Arenal Volcano, about 200 m. lower than the summit
and a distance of about 600 m from the collapse. All the occupants died.
The Red Cross are attempting to rescue the bodies today, Aug. 28.
More information could be found at the web pages
http://www.una.ac.cr/ovsi
http://www.nacion.co.cr/ln_ee/2000/agosto/24/pais1.html
http://dailynews.yahoo.com/h/p/ap/20000824/wl/costa_rica_volcano_cof.html
Topic 2 of 99 [Geo]: Vulcanism
Response 238 of 997: Marcia (MarciaH) * Wed, Aug 30, 2000 (15:00) * 18 lines
Thanks American_Patriot
VOLCANOES-
August 29 2000- Mt. Etna Explodes-
Italy's Mt. Etna Volcano erupted Monday afternoon, raining ash on the
Sicilian city of Catania to the south. No one was threatened by the lava
flows of Etna. The lava flowed from one of Etna's youngest craters
located on the southwestern flank.
August 29 2000- Mt. Oyama Erupts Twice-
Mt. Oyama is on Miyake island 120 miles south of Tokyo erupted twice on
Tuesday. Mt. Oyama's activity began in June but first erupted on
Tuesday at 4:35 AM and sent a plume of ash 5 miles into the sky. Then erupted
again at 2:53 PM (14:53). There were no immediate reports of damage or
injuries. These eruptions have so far been the largest since her last
eruption 17 years ago.
Topic 2 of 99 [Geo]: Vulcanism
Response 239 of 997: Marcia (MarciaH) * Wed, Aug 30, 2000 (15:11) * 16 lines
SHEVELUCH VOLCANO 56o38' N, 161o19' E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
PREVIOUS LEVEL OF CONCERN WAS YELLOW.
A short-lived explosive eruption was observed at 11:35 AM KDT (2235 OTC)
sending an ash-rich plume to an estimated altitude of 33,000 ft (10 km)
ASL; the ash cloud was reported as moving to the southeast. Increased
seismicity was noted at 2231-2237 followed by volcanic tremor. Seismicity
has decreased significantly and the eruption appears to be over at this
time. However, Sheveluch has had several short-lived explosive eruptions
recently as partial dome collapse has occurred and more eruptive activity
could occur.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS.
Topic 2 of 99 [Geo]: Vulcanism
Response 240 of 997: Marcia (MarciaH) * Wed, Aug 30, 2000 (21:58) * 109 lines
******************************
Indonesian volcano updates
******************************
Below is a summary of Indonesian volcanic activity reported for the week
ending 21 August. Interesting to note the Kaba appears to "active" and that
famed Merapi, after an unusually long quescence, appears to be increasing
in activity.
From: http://www.vsi.dpe.go.id/hotnews.html
VSI Weekly Report, 23 August 2000
Report for the period 15-21 August 2000
G. Kaba
During the week the weather around the volcano was cloudy, so the visual
observation can not be done clearly. But from seismicity of Kaba volcano
was still in active. That was represents from the number earthquakes.
Although the number of seismicity was decreased over last week, seismograph
was still recorded the main of volcanic earthquake, deep volcanic (A)
earthquake but the number lesser than previous. In contrast, tectonic
earthquake was increased over last week, 37 events during the week. On 17
August seismograph was recorded tremor harmonic earthquake with the maximum
amplitude of 14 mm.
The complete data were deep volcanic (A) earthquake 256 events, 1 event of
shallow volcanic (B) earthquake, and 12 events of tremor volcanic earthquake.
Kaba activity was stated in level 2 (out of four alert level).
Anak Krakatau
Anak Krakatau activity was still continuing. Although the haze obscured the
visual observation, observer was heard booming sound from the volcano.
Seismograph was still recorded many quakes, especially for explosion/small
explosion earthquakes which the number were increased over the
previous week, and infrasonic was also recorded 12 events of explosion
earthquakes but decreased for the number of deep volcanic (A) earthquakes.
The
complete seismicity were 1 event of deep volcanic (A) earthquake,
explosion/small explosion earthquake 326 events, infrasonic 12 events.
Anak Krakatau volcano is stated in level 2, alert.
G. Slamet
Central Java
109º13’20"N, 7º16’2"E, summit elevation 3676 m
Ash smoke was ejected from the summit with the height was about 50-100 m.
Seismicity was dominated by small explosion earthquake (1018 events during
the week) and tremor earthquakes, with the amplitude of about 0.5-15 mm.
Slamet activity is stated in level 2 (out of four alert level).
G. Semeru
East Java
112.92ºN, 8.11ºE, summit elevation 3676 m
Semeru activity was still high but lower than the week before. It was
represents from both visual and instrumental observations. From the volcano
was appears ash plume in white thin-brown color hit about 600 m height. The
number of seismicity were lesser than last week. Seismograph was still
recorded volcanic earthquake, but the dominant seismicity were explosion
earthquakes. The complete data were listed as follow deep volcanic (A)
earthquake 2 events, explosion earthquake 420 events, avalanche earthquake
17 events, and 5 events of tectonic earthquake.
Semeru activity is now stated in level 2, alert (out of four alert level).
G. Lokon
North Sulawesi
1º21.5’N, 124º47.5’E, summit elevation 1579 m
Based on visual observations, there is no major changes around the volcano
compare to the week before, but ash plume was still appears and reached about
100-300 m height above the rim of the crater. Night observations was notice
that the red flame was appears from the crater. The radiation was about 25
m height above the crater rim. It was observed from the Kakaskasen post
observatory. Seismicity was increased over the week before, mostly in deep
volcanic earthquake. Seismograph was recorded 3 events of shallow volcanic
(B) earthquake, 4 events of deep volcanic (A) earthquake, 40 events of
tectonic earthquake, and a continuous of tremor with the amplitude of 0.5 mm.
Lokon activity is now stated in level 3 (out of four alert level).
G. Soputan
North Sulawesi
124º41’12"N, 1º6’20"E, summit elevation 1783,7 m
On 14 August 21.05 (local time, WIB) was occurred again an explosion from
the main crater of Soputan volcano. Ash explosion was in dark grey rises to
2500 m. This activity was continued by strombolian explosion which hit 150
m height above the rim of the crater. The ash explosion was went to the
southwest. This activity was continuing until 6.00 am (local time) in the
morning and accompanied by a continuum of thundering sound which made
tremble the windows of people houses around the Maliku village (about 7 km
away from the summit). This explosion also accompanied by lava avalanche,
flowed down to the southwest 200 m away from the source. Seismicity was
still dominated by avalanche and tremor harmonic earthquakes. Tectonic
earthquake 18 events, explosion earthquake 3 events, avalanche earthquake
795 events, and a continuous of tremor earthquakes.
Soputan activity is now stated in level 4 (the highest level).
G. Merapi
Yogyakarta
110.45ºN, 7.54ºE, summit elevation 2911 m
Merapi activity continued to increase and now in level 2 (out of four alert
level). That was represents from both visual and instrumental monitoring.
By visual observations, solfatara was commonly in white thin-color with the
maximum height was about 460 m and low in pressure.
Based on instrumental monitoring, Merapi seismicity was higher, that was
marked by an increasing of both of deep volcanic (A) and shallow volcanic
(B) earthquakes which recorded in seismograph. But generally, seismicity
was still dominated by avalanche and multiphase earthquakes.
Topic 2 of 99 [Geo]: Vulcanism
Response 241 of 997: Marcia (MarciaH) * Wed, Aug 30, 2000 (22:01) * 11 lines
The AGU 2000 Fall Meeting will take place in San Francisco, Dec. 15-19 2000.
For your convenience, here is a summary list of special sessions
offered by the Volcanology, Geochemistry, Petrology (VGP) Section,
including cross-listed sessions. Convener contact information is included.
Full descriptions of each session can be found at:
http://www.agu.org/meetings/fm00_spss.html
Abstracts are due Sept. 1, 2000 by postal submission, and Sept. 7, 2000 by
electronic submission.
Topic 2 of 99 [Geo]: Vulcanism
Response 242 of 997: Marcia (MarciaH) * Wed, Aug 30, 2000 (23:28) * 13 lines
VOLCANO-
August 30 2000- Tokyo Prepares For Evacuations-
An earthquake and small eruption hit a volcanic island south of Tokyo
today, prompting naval forces to station a destroyer off the coast for a
speedy evacuation. The Tokyo city government offered shelter for the
remaining 1,600 residents of the island. Massive underground reservoirs
of magma are responsible for the recent volcanic and seismic activity on
Miyake, one of the Izu islands about 118 miles from Tokyo. Mt. Oyama
which experienced its last big eruption in 1983, shot a 1.6 mile-high
column of ash and smoke at 4:24 AM today. Hours later a magnitude 4.8
quake struck. No reports of injuries or damage were made.
Mahalo to A_P1
Topic 2 of 99 [Geo]: Vulcanism
Response 243 of 997: Marcia (MarciaH) * Sun, Sep 3, 2000 (19:36) * 3 lines
http://volcano.und.edu/vwdocs/current_volcs/arenal/arenal.html
Check out the above URL for information and a pic ture of the perfect composite cinder-cone Volcano. Hawaiian volcanoes are all shield volcanoes, as are those in Iceland.
Topic 2 of 99 [Geo]: Vulcanism
Response 244 of 997: Maggie (sociolingo) * Wed, Sep 6, 2000 (02:28) * 5 lines
You may have seen these before, but they were new to me. Here are some fantastic Hawaiian volcano pix by G. Brad Lewis - all copyright, but well worth a look see
https://secure.hialoha.net/kw/lavart/1999_catalog.html.
Topic 2 of 99 [Geo]: Vulcanism
Response 245 of 997: Maggie (sociolingo) * Wed, Sep 6, 2000 (02:30) * 3 lines
If that link doesn't work (it doesn't show up linked on here) try http://www.lavart.com/
and click on image catalog
Topic 2 of 99 [Geo]: Vulcanism
Response 246 of 997: Marcia (MarciaH) * Wed, Sep 6, 2000 (21:18) * 27 lines
****************************************
Volcanoes, Aerosols and Climate meeting
****************************************
VOLCANOES, AEROSOLS AND CLIMATE
Royal Meteorological Society
Volcanic and Magmatic Studies Group of the Geological Society of London
Aerosol Society
Royal Geographical Society, 1 Kensington Gore, London SW7 2AR, UK
Wednesday 18 October 2000, 1-5pm
The meeting will cover several aspects of the relationship between
volcanism and climate, from measurements of gases as they emanate
from active volcanoes, through the processes of aerosol formation,
growth and transport in the troposphere and stratosphere, and the
impacts of volcanic aerosol upon the chemical composition, radiation
budget, and climate of Earth's atmosphere.
The meeting is free and open to all who are interested.
For further details see:
http://www.royal-met-soc.org.uk/wedmeet.html
http://www.royal-met-soc.org.uk/wedabs001018.html
Topic 2 of 99 [Geo]: Vulcanism
Response 247 of 997: Marcia (MarciaH) * Wed, Sep 6, 2000 (21:22) * 58 lines
Ash eruptions - Komagatake,Popocatepetl,Tavurvur(Rabual)
The full report from the Japan Times (09/06/00) is available at:
http://www.japantimes.co.jp/news.htm
excerpt:
SAPPORO (Kyodo) A volcano in Hokkaido erupted Monday night for the first
time in nearly two years, the Meteorological Agency said early Tuesday.
Mount Komagatake in southwestern Hokkaido erupted at 10:14 p.m. ...There have
been no reports of casualties or damage. At around 5 a.m. Tuesday, the
Sapporo District Meteorological Observatory reported seeing smoke from the
volcano
reaching as high as 500 meters above the volcano...The observatory also
reported
that a seismic tremor was observed on the 1,133-meter mountain, which is
about
120 km southwest of Sapporo.
*************************
Popocatepetl, Mexico
*************************
from the CENAPRED September 5 Bulletin
http://www.cenapred.unam.mx/boletines.html
September 4. At 03:47 a moderate large plume of ash was produce. The
doppler radar detected the plume, that occurred at night. There were
reports ash fall in many towns in the North-west flank: Amecameca, Ozumba,
Tepetlixpa, San Juan Tehuxtitlan, Zoyatzingo and Valle de Chalco. Some ash
also fell on the South limit of Mexico City. The intense phase of this
event lasted 3 minutes, and was followed by 25 minutes of high frequency
tremor. A tectonovolcanic event, below the crater and of magnitude 1.8 also
ocurred. It is recommended not to approach the volcano to less than 7 km
from the crater.
The traffic light of volcanic alert is maintained yellow.
(Recent images of the volcano can be viewed in this web page.)
**************************
Tavurvur (Rabual), PNG
**************************
full Reuters report at:
http://dailynews.yahoo.com/h/nm/20000906/wl/papua_volcano_dc_1.html
excerpt:
BRISBANE (Reuters) - Thick clouds of volcanic ash have blown over the Papua
New Guinea town of Rabaul and authorities said on Wednesday they were
watching a nearby volcano closely for signs of increased activity. The
Tavurvur volcano in PNG's remote northeast province began blowing smoke and
debris last week but vulcanologists said the activity was still considered
normal and no alert had been issued to warn townspeople in the New Britain
island trading port. "In the past several days we have had strong
southeasterly winds which have blown the ash directly into Rabaul," Ima
Itikarai, director of the Rabaul Vulcanological Observatory, told Reuters
by telephone. "It is not at the stage where we would declare it critical,
but we will keep a close watch on it."...Itikarai said the current activity
is similar to events in 1995 and 1996, when Tavurvur spewed debris for
several hours at a time over a period of days before calming down.
Topic 2 of 99 [Geo]: Vulcanism
Response 248 of 997: Marcia (MarciaH) * Sun, Sep 10, 2000 (23:23) * 17 lines
VOLCANO-
Sept 7 2000- Volcano In Papua New Guinea Explodes-
Tavurvur Volcano, located in a remote NE province of Papua New Guinea,
exploded Wednesday. The volcano began showing signs of increased
activity last week, spewing smoke and volcanic debris. The activity was
within the mountain's normal range, and no alerts were issued. Rabaul,
located 500 miles NE of the capital Port Moresby, is built on the caldera of
the volcano. The city suffered extensive destruction in 1994 when
Tavurvur erupted simultaneously with a neighboring volcano, Vulcan, killing
five people. Both of the volcanoes erupted in 1937 triggering tsunamis
that flooded the city. Rabaul is surrounded by 6 volcanoes, and is
located on the Pacific's Ring of Fire.
Thanks to A_P again!
Topic 2 of 99 [Geo]: Vulcanism
Response 249 of 997: Carys (Carys) * Mon, Sep 11, 2000 (17:43) * 1 lines
Hello Marcia. I thought it best to make my maiden post at Geo on this conference. Since you mentioned living on an island with a large volcano -- Hawaii, the big island of course. You live in the shadow of the great goddess Pele. There used to be a beautiful black sand beach on Hawaii. It's gone now, under lava fields. The process of island building goes on!
Topic 2 of 99 [Geo]: Vulcanism
Response 250 of 997: Marcia (MarciaH) * Mon, Sep 11, 2000 (20:24) * 15 lines
Kalapana black sand beach is no more and I have it documented inch by painful inch in photographs as it was paved over by 20 feet of faceless lava. However, as the leading edge of molten lava hit the sea it fractured into minute particles and remade a balck sand beach several hundred feet from the former shoreline. Locals whose houses escaped collected coconuts which had sprouted in the kipukas (kipuka = island of original land which the new lava left untouched) and planted them in an arc around the new beach. It is getting pretty out there and they hold surfing contests again. Pele giveth and Pele taketh away. The current eruption just down the coast from Kalapana is still ongoing and has added over 5000 square acres to our island. The cartographers have a constant updating job here. I have watched two mini mountains form which are now on maps and have names. It is fascinating!
I was wondering when you would post in my conference...Aloha! E komo mai!
Original Kalapana Black Sand Beach\
New Black Sand Beach at Kalapana
Topic 2 of 99 [Geo]: Vulcanism
Response 251 of 997: Maggie (sociolingo) * Thu, Sep 14, 2000 (02:05) * 39 lines
Large rocks in strange places
http://www.islenews.com/
By Staff | 2000.9.7 - 17:19:53 HST
Sometimes in science you find something that theory says you shouldn't. Then your pulse starts racing. Are your observations or calculations wrong? Is the theory wrong? Or is there a middle ground, in which observations can be fit to theory if both are tweaked a little?
In late August two volcanologists from the USGS (one from HVO) and one from the Smithsonian Institution were faced with this dilemma. We don't yet know what the final outcome will be, but we're pretty excited.
As this column has previously noted, Kilauea has exploded more often than many people think. Ongoing research at HVO is trying to learn as much as possible about these explosions, for flying rocks are clearly hazardous events that will impact the public.
We went looking for rocks that were thrown out of the volcano about 1,000 years ago. Work in past months had shown that a wide variety of material was exploded from Kilauea then, mostly cherry-sized scoria and other fine-grained material. However, several times explosions were apparently more violent or powerful. They ejected large, heavy rocks, much like those from the 1924 explosions that litter the surface around Halema`uma`u today. The question we asked was how far out were such rocks thrown?
Using a hand-held GPS unit, we established a grid between the Hilina Pali Road and the `Ainahou Ranch Road. The grid is about 700 m (2,300 feet) on a side. At each node of the grid, we spent a total of 18 minutes looking for rocks on the surface-6 minutes per person with a full crew, and 9 minutes with only two of us. We selected the largest 10 rocks we could find during the search. It was like an Easter egg hunt, except the rocks can't be eaten and Nature put them there.
We were searching for the largest rocks we could find. We were not interested in those that broke off the surface of the lava flow beneath our feet, but in those that were clearly foreign-that reached their resting place by flying through the air ballistically. After a little practice, recognizing the ballistics became a simple matter. Some of the rocks are even coarse-grained gabbro, which cooled and crystallized underground before being blasted out.
What we found surprised, even shocked, us. Rather than seeing few, if any, large rocks so far from the caldera, we found lots. And some were very large.
At a distance of 10 km (6 miles) from the summit, we found one rock (a gabbro) weighing 1292 g (2 lbs 13 oz.). At 7.9 km (4.7 miles) from the summit, we found another weighing 1998 g (4 lbs 5 oz.). Many others weigh 100 g (3.5 oz.) or more.
When we compared our findings with theoretical models of how far such large rocks could have been thrown from a volcanic vent, we found that we were observing the impossible. The models simply say no dice, it can't be done. Even if we assume that the source for the rocks was on the east rift zone, say near Pauahi Crater or Mauna Ulu, the distance of more than 5.25 km (3.2 miles) is still too great for the models to accept. But, models or no models, the rocks traveled through the air to get where we found them-and that has to be explained.
We think we are on to something. Kilauea has likely had explosions that were either more powerful, or of a different type, than existing theoretical models can explain.
Before you toss out theory, all steps in the observation and interpretation process must be checked and double checked. We are doing that now. Explosions of such unusual power or type are significant; we can leave no stone unturned (pun intended) in trying to determine their nature and cause.
Topic 2 of 99 [Geo]: Vulcanism
Response 252 of 997: Maggie (sociolingo) * Thu, Sep 14, 2000 (02:17) * 28 lines
Waiting for the pause that refreshes
http://www.islenews.com/
By Staff | 2000.8.31 - 18:17:49 HST
What do Kilauea Volcano's eruption and Hilo's 7:30 a.m. traffic have in common? For one thing, lots of stops and starts. The stops and starts in the eruption at Kilauea are the by now familiar pauses; the stops and starts in busy Hilo traffic might be referred to in more colorful terms.
The latest pause in Kilauea's ongoing eruption occurred just over a week ago and was brief. The pause started late on Wednesday, August 23, and ended Saturday, August 26. This was the first Y2K pause but the 30th of the current eruptive episode, which began in February 1997. Eruptive pauses can be short--lasting only a few hours--or long--lasting days or even tens of days. For avid local volcano viewers and once-in-a-lifetime visitors, a pause can be a frustrating experience, since lava stops flowing completely, and there is little, if anything, to see that is red and molten. However, for residents and visitors who are acutely aware of air quality, a pause can be a refreshing experience.
Since the current eruption began in 1983, Kilauea has released a total of around 8 million tons of toxic sulfur dioxide gas (SO2)--enough to fill 400,000 Goodyear blimps or 350 billion party balloons. This gas, which reacts in the atmosphere to form sulfuric acid and other aerosols, is the principle gas responsible for the formation of volcanic smog (vog). At Kilauea, the amount of sulfur dioxide gas released is directly proportional to the amount of lava erupted. Therefore, when the lava eruption rate declines, there is generally a decrease in the amount of SO2 discharged.
During a long pause, the amount of SO2 released from the eruption site is usually drastically reduced. For example, during a 25-day break in the eruption in early 1997, so little SO2 was being emitted that it could not be detected downwind of the eruption site using our standard measurement techniques. This abrupt decrease in gas confirmed that, in addition to the absence of lava at the surface, magma had also withdrawn from beneath Pu`u `O`o.
Several months later, SO2 emissions were still only around half their typical value, reflecting the sluggish start-up of the eruption. During this delightful three-month period of very low SO2 emissions, Kona residents reported the return of the clear air that was the norm before 1986, when the eruption became continuous. Residents who had moved off-island to escape the hazy Kona air quality inquired whether the improved conditions were likely to continue and it might be time to move back. The respite was brief however, and as the lava production came up to full volume, so did the SO2 emissions, and thereby the air pollution problem.
During brief pauses, SO2 emissions may decline somewhat but not stop altogether. During the most recent event, measurements showed that the amount of SO2 released during the pause was still around two-thirds of what we had measured prior to the pause. Although no active lava was flowing, residual degassing of cooling lava, tubes, the vent areas, and shallow magma beneath Pu`u 'O`o continued. It can take many days for all of the gas to escape from the material remaining in the system, so a brief pause may give little chance for chronic volcanic air pollution, such as that in Kona, to clear.
Close to the emission sources, it may also be difficult to detect that a decrease in SO2 has occurred. Under steady trade wind conditions, a compact plume of the residual SO2 from the inactive eruption site can cross the Chain of Craters Road in Hawai`i Volcanoes National Park, 9 km (5.5 miles) from the emission source. This plume is concentrated enough so that a person would still experience the pungent smell, taste and ensuing watery eyes associated with SO2 exposure. Although the latest pause in Kilauea's ongoing eruption was brief, an extended "pause that refreshes" may lie in the future.
Topic 2 of 99 [Geo]: Vulcanism
Response 253 of 997: Marcia (MarciaH) * Thu, Sep 14, 2000 (17:18) * 2 lines
Maggie!!! This is hilarious stuff!!! Whoooooo...I did not know it was even out there let alone for God and everyone to read. Thanks for putting it here!!!
Kilauea continues to erupt on the southwest flank and continues to add acreage to the island as it does so....and more black sand for the beaches. The House Male assured me that the new Kalapana black sand has all washed away and thatr this other beach is a poor replacement for the old one. But, it is one of the few remaining beaches in the area. He said there are 200-foot (61 M) cliffs now where the "new" black sand beach used to be.
Topic 2 of 99 [Geo]: Vulcanism
Response 254 of 997: Marcia (MarciaH) * Thu, Sep 14, 2000 (19:52) * 17 lines
*******************************
Aoba Volcano, Vanuatu website
*******************************
From: Roberto Carniel
A short note to inform you that, in collaboration with Charlie Douglas and
Sandrine Wallez, Geohazard Mitigation section of the Department of Geology,
Mines and Water
resources of Vanuatu, and Michel Halbwachs and Michel Lardy, of French IRD,
we prepared a page regarding the current situation at Aoba volcano, in the
island of Ambae, Vanuatu.
STROMBOLI ON LINE, by J. Alean & R. Carniel, http://stromboli.net
From homepage follow link: *Eruptions worldwide", then "Aoba, Ambae, Vanuatu".
Best regards.
Roberto Carniel.
University of Udine, Italy
Topic 2 of 99 [Geo]: Vulcanism
Response 255 of 997: Maggie (sociolingo) * Fri, Sep 15, 2000 (04:06) * 1 lines
(did you see 251 as well?)
Topic 2 of 99 [Geo]: Vulcanism
Response 256 of 997: Maggie (sociolingo) * Fri, Sep 15, 2000 (05:42) * 39 lines
You probably know all this but it was new to me ...The following near-real-time Earthquake Bulletin is provided by the National
Earthquake Information Service (NEIS) of the U. S. Geological Survey as part of
a cooperative project of the Council of the National Seismic System. For
a description of the earthquake parameters listed below, the availability of
additional information, and our publication criteria, please finger
qk_info@gldfs.cr.usgs.gov.
This Bulletin is updated every 5 minutes, if necessary. The same Bulletin
is also available via the Internet at:
http://wwwneic.cr.usgs.gov/neis/bulletin/bulletin.html and that is the
preferred means of obtaining it.
Updated as of Thu Sep 14 22:22:40 GMT 2000.
DATE-(UTC)-TIME LAT LON DEP MAG Q COMMENTS
yy/mm/dd hh:mm:ss deg. deg. km
00/09/12 06:43:13 35.35N 99.32E 33.0 4.7Mb A QINGHAI, CHINA
00/09/12 09:50:50 22.65S 179.92W 544.7 4.6Mb B SOUTH OF FIJI ISLANDS
00/09/12 09:54:38 36.42N 120.99W 9.7 2.8Md CENTRAL CALIFORNIA
00/09/12 10:54:12 6.66N 73.05W 163.9 5.0Mb A NORTHERN COLOMBIA
00/09/12 15:54:33 27.41S 177.16W 33.0 4.8Mb B KERMADEC ISLANDS REGION
00/09/12 16:27:24 5.42S 101.76E 33.0 6.1Ms A SW OF SUMATERA, INDONESIA
00/09/13 00:11:26 51.00N 179.28E 33.0 4.3Mb B RAT ISLANDS, ALEUTIAN ISLANDS
00/09/13 00:13:33 23.86S 66.71W 33.0 4.9Mb B JUJUY PROVINCE, ARGENTINA
00/09/13 03:55:10 27.76N 51.74E 33.0 4.7Mb B PERSIAN GULF
00/09/13 04:17:04 27.77N 51.72E 33.0 4.8Mb A PERSIAN GULF
00/09/13 08:47:50 7.91S 74.41W 147.1 4.3Mb A PERU-BRAZIL BORDER REGION
00/09/13 09:04:22 27.48N 51.85E 33.0 4.7Mb B PERSIAN GULF
00/09/13 10:08:01 42.73N 145.09E 33.0 4.4Mb A HOKKAIDO, JAPAN REGION
00/09/13 10:34:53 58.38S 25.05W 33.0 4.8Mb B SOUTH SANDWICH ISLANDS REGION
00/09/13 13:09:46 27.82N 51.70E 33.0 5.1Mb A PERSIAN GULF
00/09/13 15:11:20 34.18N 95.08E 33.0 4.7Mb B QINGHAI, CHINA
00/09/13 20:39:03 9.12N 126.10E 132.0 4.7Mb B MINDANAO, PHILIPPINES
00/09/13 22:15:09 44.51N 140.56E 248.4 4.2Mb B EASTERN SEA OF JAPAN
00/09/13 22:29:10 54.31S 136.80W 10.0 5.3Mb C PACIFIC-ANTARCTIC RIDGE
00/09/14 14:59:57 15.65S 179.80E 33.0 6.2Ms A FIJI ISLANDS
00/09/14 17:33:27 22.43S 176.35W 104.5 5.2Mb A SOUTH OF FIJI ISLANDS
Topic 2 of 99 [Geo]: Vulcanism
Response 257 of 997: Maggie (sociolingo) * Fri, Sep 15, 2000 (05:48) * 18 lines
Also
http://www.drudgereport.com/quake.htm
The areas covered are:
LIVE REPORTS
WORLD LIST
LOS ANGELES LIST
LOS ANGELES MAP
SAN FRANCISCO LIST
SAN FRANCISCO MAP
INSTA CALI MAP
EMERGENCY INFO
SEISMO/H'WOOD
ENTIRE US MAP
AP QUAKE NEWS
UPI/REUTER QUAKE NEWS
MAMMOTH VOLCANO WATCH
Topic 2 of 99 [Geo]: Vulcanism
Response 258 of 997: Marcia (MarciaH) * Fri, Sep 15, 2000 (17:11) * 1 lines
Yup...post them daily in Geo 26, but I appreciat your posting them anyway. I am desperately trying to retrieve my foot from my mouth in which it has been firmly wedged all week! Appreciate your diligence. Btw, falcon came here in July and apparently was soooo bored that he has not been back since...!
Topic 2 of 99 [Geo]: Vulcanism
Response 259 of 997: Maggie (sociolingo) * Sat, Sep 16, 2000 (11:49) * 16 lines
Friday September 15 2:35 PM ET
Mexico's Popocatepetl Volcano Spouts Steam And Gas
MEXICO CITY (Reuters) - Mexico's Popocatepetl volcano spewed a column of steam and gas nearly a mile into the air on Friday but authorities said there was no threat to people living nearby.
The Center for the Prevention of Disasters (CENAPRED) said the volcano, 40 miles east of the nation's capital, remained on yellow alert, meaning it could erupt in weeks or months but probably no sooner.
The center advised people to stay at least 4.3 miles away from Popocatepetl, which means ``smoking mountain'' in the indigenous Nahuatl language.
Ramon Pena, director of Plan Popocatepetl at the center, told local radio the exhalation was normal for an active volcano. He attributed the emission to the presence of snow on the crater that evaporates rapidly on contact with the magma.
Recently, the 17,887-foot volcano has shown increased activity. ``Popo,'' as it is known locally, was inactive from 1927 to 1994, when there was a moderate eruption.
Since then it has been active, regularly sending up smoke and ash columns. In November 1998, the volcano spewed fragments of lava rock.
Topic 2 of 99 [Geo]: Vulcanism
Response 260 of 997: Marcia (MarciaH) * Sun, Sep 17, 2000 (15:01) * 8 lines
VOLCANO-
Sept 10 2000- Tavurvur, Rabual Caldera, New Britian Island, Papua New
Guinea Erupts-
On Sept 6, the stratovolcano Tavurvur erupted sending thick clouds of
ash over the town of Rabual. Tarvurvur began showing signs of increased
activity the week before, but not alerts were issued.
*Mahalo, A_P*
Topic 2 of 99 [Geo]: Vulcanism
Response 261 of 997: Marcia (MarciaH) * Sun, Sep 17, 2000 (15:15) * 55 lines
Asama-Yama Volcano Japan................
Asama-Yama, Japan
Location: 36.4N, 138.53E
Elevation: 8364 Ft. (2550 m)
Asama-yama is a stratovolcano. Three overlapping bodies make up this
volcano. It consists of a young stratovolcano with two craters lying on a
shield volcano. The shield volcano rests on an older stratovolcano.
Kurohu-yama is the name of the western crater rim of the older
stratovolcano. It stands 7888 ft (2405 m) high. Erosion has enlarged this crater
to 1.25 miles (2 km) around. Water rests in the crater and is drained to
the SW. The eastern part of this stratovolcano has been down-faulted
and buried under a shield volcano. A younger stratovolcano also lies on
top of this shield. This younger stratovolcano has two craters. The SW
rim of the outer crater is Maekake-yama. It stands 8177 ft. (2493 m)
high. The outer crater is ~3900 ft. (1200 m) across from east to west and
~3000 ft. (900 m) across from north to south. This crater is about 1.25
miles (2 km) east of Kurohu-yama. Kama-yama is a cone at the center of
the outer crater. It stands 8364 ft (2550 m) high. This cone rises 558
ft. (170 m) above the bottom of the crater. Its crater pit is ~1150 ft.
(350 m) across and very active. The depth of this crater changes with
time. It was 820 ft. (250 m) deep in 1893, but it was completely filled
with lava in 1912. All recorded eruptions have taken place from this
crater pit. Asama-yama sits on a flat plateau. This plateau is about 3300
ft. (1000 m) high. It is made of rocks erupted from other volcanoes,
lake deposits and rocks make up the older volcanoes. Hotoke-iwa exists as
a bulge to the SW of the outer crater of the younger stratovolcano.
Hotoke-iwa is a shield volcano with a steep slope. The first stage of
activity of Asama was the eruption of Kurohu-yama. This cone shaped
stratovolcano grew 6560 ft. (2000 m) from its base at the time. Its crater
began to grow by erosion once the cone itself stopped growing. The eastern
part of Kurohu-yama was destroyed by down-faulting and large scale
steam explosions. The second stage of activity involved the eruption of
Hotokeiwa. Several lava flows occurred during this stage. These are now
exposed at Hotokeiwa SSE of the present active crater. Ko-asama-yama is a
parasitic lava dome on the eastern side of Asama. It stands 5428 ft
(1655 m) high and is made of a rock similar to dacite erupted during the
formation of the shield volcano. The western side of the shield was
destroyed by down-faulting. The third state of activity consisted of the
eruptions of two pumice flows. These flows had great volume that spread
over wide areas to the north and south of the shield volcano. Andesite
stratovolcanoes grew during the fourth stage of activity. The recent
eruptions produced thick lava flows and pyroclastic ejecta together with
pyroclastic flows (nuees ardentes). On the southern side of this cone
there is a parasitic lava dome made of andesite. Its name is Sekison-zan.
It rises 656 ft. (200 m) from the surrounding cone. This cone is
younger than the cone of Kurohu-yama but older than the recent cone. Its age
relation with the shield volcano is unknown. Asama has erupted 121
times. Most of these eruptions have been Vulcanian. A weak solfatara is
active at the SW crater rim of the volcano. The last eruption was in 1990.
American_Patriot
[Yahoo! Clubs: WARNING Volcanology Activated]
Topic 2 of 99 [Geo]: Vulcanism
Response 262 of 997: Maggie (sociolingo) * Mon, Sep 18, 2000 (07:48) * 6 lines
This was a new site to me ...and I have been surprised at the sheer number of African volcanoes ...several I knew about but many here are new to me ...I think everyrone has pix...often from space, great detail and documented. Too much to explore right now, but I'll be coming back to this site for sure .......
http://volcano.und.nodak.edu/vwdocs/volc_images/africa/africa.html
I found this site through http://www.viexpo.com/dmstest/volcano.html
which is also well worth looking at ....
Topic 2 of 99 [Geo]: Vulcanism
Response 263 of 997: Marcia (MarciaH) * Mon, Sep 18, 2000 (23:01) * 1 lines
Been there and done that. Thanks for reminding me...!
Topic 2 of 99 [Geo]: Vulcanism
Response 264 of 997: Carys (Carys) * Sat, Sep 23, 2000 (10:36) * 1 lines
Marica, I'm sorry it took me ages to get back. I can't get here as often as I'd like having all those "Mom" things to do. Thank you so much for the lovely greeting and the information and beautiful photos of the two Kalapana black sand beaches. It must have been very painful to have seen it disappear. I admire and am amazed at the the people who had the forsight to collect the coconut sprouts and plant them on the new beach.
Topic 2 of 99 [Geo]: Vulcanism
Response 265 of 997: Marcia (MarciaH) * Sat, Sep 23, 2000 (22:41) * 3 lines
There are sacred-to-Hawaiian-Ohana (extended family) places all over the place down around Kalapana. There was little grieving by the Hawaiians who have lived with Madame Pele forever. Rather, the celebrate the new land and consecrate it with offerings of food, flowers, carefully made into haku leis, and chants.
One hike I took was with a class of geology students. My hiking buddy a local girl. She prayerfully collected flowers for her offering and prayers to Pele for safe passage over the just-barely-hardened flows. I still have the photo of her offerning and will try to scan it. There were about 20 students, one professor and one mom (guess who) who went on the night hike, and none intruded into her quiet departure from us when we reached the new lava on foot. She was just about 5 minutes away from us, out of sight, and no one doubted that her offering and chants helped us escape unscathed. One place we crossed made my hiking boots' soles smoke! It also poured on us at one point - so heavily that our feet made squelching sounds as we walked. But, in Hawaii, rain is a blessing. No one complained and we were all toasty-warm and dry by the time the hike was over!
Topic 2 of 99 [Geo]: Vulcanism
Response 266 of 997: Marcia (MarciaH) * Sat, Sep 23, 2000 (22:43) * 1 lines
A long story and no mention of the coconuts. Part of the Hawaiian respect for the 'Aina (the land) is their replanting where the lava has taken away.
Topic 2 of 99 [Geo]: Vulcanism
Response 267 of 997: Marcia (MarciaH) * Thu, Sep 28, 2000 (21:25) * 109 lines
***************************
Indonesian updates
***************************
Below is a summary of some of the Indonesian volcanic activities for the
week ending 18 September. Kerinci, Anak Krakatau, Slamet, Semeru
(pyroclastic flows too), Batur, Api Siau (nightime glares and continuous
tremor), Lokon-Empung (nighttime glow), Soputan, Ijen (minor ash plume) and
Merapi (rockfalls and ash falls) all continued to be active.
Following from: http://www.vsi.dpe.go.id/news/index.html
Weekly Report No. 581
12 - 18 September 2000
Kerinci
Jambi, Sumatera; 1°41.5' S, 101°16' E, summit elev. 3,800 m
During this week, the activity of Kerinci volcano was still ongoing.
Visually, a white thin-thick as plume was observed with a maximum height
reached about 300 m above the crater. Seismic record was still dominated by
emission earthquakes, but the seismicity decreased compare to the last
week. Recorded activities were emission earthquake 129 events and tectonic
15 events.
The alert level of Kerinci volcano is in level 2.
Anak Krakatau
Sunda strait; 6°6'5.8" S, 105°25'22.3" E
Anak Krakatau was covered by smog, so that the visual observation could not
be done from the observatory post. Boom sound was not heard from the post.
Seismograph was still recording emission earthquakes but the number
decreased compare to the last week. Infrasonic sensor recorded 4 explosion
earthquakes. Recorded activities were deep volcanic earthquake 2 events,
emission/explosion earthquake 1,477 events and tectonic earthquake 1 event.
Anak Krakatau volcano is in level 2.
Slamet
Central Java; 7°14.30' S,109°12.30' E
During this week, Slamet volcano produced a white medium-thick ash plume
with the height of 50-100 m above the summit. Seismicity was dominated by
emission and tremor earthquakes with the amplitude of 0.5-5 mm, but there
was no a significant change compared to the last week. Seismograph recorded
shallow volcanic earthquake 5 events, continuous tremor and emission
earthquake 212 events.
Slamet volcano is in level 2.
Semeru
East Java; 8°6.50' S, 112°55' E
The visual observation showed that a white gray thin ash plume rose up to
600 m above the summit. Seismicity was still dominated by explosion
earthquakes and the number showed a increase, whereas the number of ash
fall decreased. During this week, seismograph recorded 623 explosion
earthquakes, pyroclastic flow 3 events, tremor 2 events and ash fall 72
events.
The alert level of Semeru volcano is in level 2.
Batur
Bali; 8°14.30' S, 115°22.30' E
During this week, from the visual observation, Batur volcano produced a
white thin ash plume with the height of 10 m above the crater edge.
Seismograph recorded shallow volcanic earthquake 3 events, deep volcanic 8
events, emission earthquake 4 events and tectonic 14 events.
Batur volcano is in level 2.
Karangetang
Siau island; 2°47' N, 125°29' E
A white thin-thick ash plume from the main and the second craters rose up
to 400 m above the craters. At night, was observed the light around the
crater that the height reached 75 m above the crater. Continuous tremor
volcanic dominated seismic activity, with the amplitude of 0.5-29 mm, and
only 1 event of tectonic was recorded.
Karangetang volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
During this week, there was no a significant change from this volcano
compared with the last week. A white thin-thick ash plume rose up to 400 m
high from the crater edge. A light was seen around the crater with the
height of 25 m above the crater. Tremor earthquake was recorded with 0.5-1
mm of amplitude and also recorded 32 tectonic earthquakes.
Lokon volcano is in level 3
Soputan
North Sulawesi; 1°6.5' N, 124°43' E
A significant change of Soputan volcano was not seen visually. A white
thin-medium emission ash plume rose 50 up to 200 m above the summit.
Seismicity was dominated by ash fall earthquakes (178 events). Seismograph
also recorded deep volcanic 6 events and tectonic 33 events.
Soputan volcano is in level 4.
Ijen
East Java; 8°3.5' S, 114°14.5' E
A white thin-medium ash plume rose up to 25 m above the crater. Seismicity
showed a decreased in the number of volcanic earthquakes, but tremor
volcanic earthquakes were recorded continuously. The complete seismicity as
follows : deep volcanic 1 event, shallow volcanic 11 events and tectonic 8
events.
Ijen volcano is in level 2.
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Based on the visual and instrumental observations, the alert level of
Merapi volcano is waspada Merapi (level 2). The visual observation showed
that the volcano produced a white thin solfatar with the maximum height of
250 m from the summit and the pressure was low. Seismicity did not show a
significant decrease and increase in volcanic activity. The activities were
dominated by ash fall and multiphase earthquakes. Shallow and deep volcanic
events still occurred.
Merapi volcano is in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 268 of 997: Marcia (MarciaH) * Fri, Sep 29, 2000 (18:42) * 35 lines
Update On Previous Volcanic Cases- thanks to A_P
VOLCANOES-
Sept 20 2000- Japan Volcano Threatens To Explode-
Hundreds of earthquakes have jolted the region near central Japan's
Mt.Asama Volcano since the beginning of the week. On Monday, at least 138
quakes shook the mountain, located on the border between Nagano and
Gunma prefectures. There haven't been any evacutions. The tremors did
however increase on Tuesday by 40 an hour. It has been spewing steam. This
volcano has been silent for the last 217 years. A major explosion in
1783 killed 1,151 people.
Sept 20 2000- Mexican Volcano Threatens To Erupt-
On Wednesday a new lava dome formed on Popcatepetl Volcano which means
that lava is rising to the surface and could cause a major eruption.
The last major eruption of this volcano was in 1994 when it awoke from
its 67-year dormancy. Alert status has not been raised. The nearest
living establishment is 5 miles away from the base of this 17,259 foot
volcano.
Sept 22 2000- Guatemalan Volcano Spews Ash Cloud-
An active volcano in Guatemala shot out a huge cloud of ash and smoke
on Thursday, leaving nearby communities blanketed in ash. Plans to
evacuate residents is in consideration. Volcano del Fuego, which is Spanish
for Volcano of fire, was put on orange alert. The last major eruption
of this volcano was in May 1999.
Sept 28 2000- Japan Volcano Erupts-
Mt. Komagatake, a volcano in northern Japan, exploded on Thursday, but
there were no reports of damage or injuries. The 3,716-foot volcano,
located 441 miles NE of Tokyo, on the island of Hokkaido, last erupted
Sept.4. A major eruption of the volcano in 1929 killed two, and a 1856
eruption claimed 20.
Topic 2 of 99 [Geo]: Vulcanism
Response 269 of 997: Marcia (MarciaH) * Fri, Sep 29, 2000 (19:15) * 18 lines
Mt. Cameroon, Cameroon
Location: 4.20N, 9.17E
Elevation: 13,428 ft (4095 m)
Mt. Cameroon is a poorly studied stratovolcano located in the nation of
Cameroon, 180 miles west of the capital Yaounde. This volcano is also
known locally as Mt. Faka and "Chariot of the Gods". It is one of
Cameroon's main tourist attractions. Thousands of people participate in a
race up its rocky slopes each year. It is the highest peak in West and
Central Africa. Cameroon has erupted six times this century, most recently
in the summer of 1999. Eruptions generally occur on the flanks of the
volcano and produce small cinder cones and lava flows. Cameroon was the
site of one of the earliest recorded volcanic eruptions--in the 5th
century BC--observed by a Cathaginian ship captain while sailing down the
Atlantic Coast of Africa.
Mahalo to A_P
Topic 2 of 99 [Geo]: Vulcanism
Response 270 of 997: Marcia (MarciaH) * Thu, Oct 5, 2000 (13:42) * 26 lines
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Popocatepetl, Mexico
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Mexican Volcano Spouts Steam And Ash Column
full Reuters report at:
http://dailynews.yahoo.com/h/nm/20001004/sc/mexico_volcano_dc_2.html
excerpt:
Mexico's Popocatepetl volcano...spouted a 4-mile column of ash on Tuesday,
its biggest this year, authorities said....CENAPRED said on Sept. 15 that
Popocatepetl's main volcanic crater had been sealed by the formation of a
dome-like structure. Tuesday's eruption of ash, gases and water came as the
dome became slightly uncovered, Valdes said.
CENAPRED bulletins and links to images are available at:
http://www.cenapred.unam.mx/boletines.html
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Colima, Mexico
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The 22 September update for Colima volcano in Mexico indicate weakening
activity but steam and ash emissions still are occurring.
Loosely translated from URL
Topic 2 of 99 [Geo]: Vulcanism
Response 271 of 997: Marcia (MarciaH) * Thu, Oct 5, 2000 (13:43) * 43 lines
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Mt. Komagatake and Mt. Asama, Japan activity
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Information from Chris Eisinger
Mt. Komagatake erupted last week on Thursday, Sept. 28, following
an earlier eruption on Sept. 4. An AP news report is available at:
http://dailynews.yahoo.com/h/ap/20000928/wl/japan_volcano_1.html
AP news also reported previously that Mt. Asama in central Japan was
shaken by 138 earthquakes on Monday, Sept. 18 (compared with about 10
daily in recent months). By late Tuesday, Sept. 19 there were an average
of 40 volcanic tremors an hour. The last major eruption of Mt. Asama
in 1783 killed over 1,000 people.
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White Island and Ruapehu, NZ updates
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From: Dan Shackelford
For the week ending 29 September, White Island's MH vent continued to emit
gas with a very small amount of ash and the crater opened on 27 July
produced gas. Also, a swarm of high-frequency earthquakes took place, as
well as periodic low-frequency tremor.
Minor tremor noted at Ruapehu, but no change in surface activity.
From: http://www.gns.cri.nz/hazardwatch/latest/gweekvo.htm
White Island
During the week a swarm of small high-frequency earthquakes were recorded.
These were sourced at or near White Island. There has also been periodic
low-frequency tremor recorded. There have been no reported changes in
activity, with MH vent still producing a very small amount of ash. Both the
MH and the unnamed crater (formed July 27th) are emitting steam and gas.
The Scientific Alert Level remains at 1.
Other volcanoes
A small amount of volcanic tremor was observed at Ruapehu during the week.
No surface activity has been reported. The Scientific Alert Level remains
at 1.
Topic 2 of 99 [Geo]: Vulcanism
Response 272 of 997: Marcia (MarciaH) * Thu, Oct 5, 2000 (13:44) * 53 lines
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Mount Ulawun, Papua New Guinea
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From: Dan Shackelford
Papua New Guinea's Ulawun volcano erupted briefly on 29 Sept. 2000 at 0230
from its summit. Heavy ash falls prompted evacuations. As of 2-3 Oct. there
have been no further eruptions but the summit crater continues to emit
white fume, while low - moderate seismicity continues, including harmonic
tremor.
Full report: http://www.postcourier.com.pg/20001002/news02.htm
excerpt:
Mt Ulawun quiet but stage 2 alert remains.
The stage two alert on Mount Ulawun will be maintained indefinitely despite
a decline in the volcanic activity.
Mt Ulawun, on the border of East and West New Britain provinces, erupted at
2.30am on Friday but no casualties or major damages had been reported so far.
Government officials say that although the eruption had stopped, there was
still low to moderate seismic activity, which indicate that the volcano was
still active.
Reports of the early morning eruption were not received at the Rabaul
Volcanological Observatory until about 8am, because of communication
problems with its monitoring station on Mount Ulamona.
A team of government officials from East New Britain comprising the senior
volcanologist Ima Itikarai, provincial disaster co-ordinator Peniel Lotu
and health adviser Bernard Lukara flew to the area to assess the situation.
Their report was still to be ratified by the East and West New Britain
provincial disaster committees.
But government officers in Bialla said there has been a decline in
activity. The summit of the volcano was clear while the vent was emitting
thin white vapor.
Full report: http://www.postcourier.com.pg/20001003/news08.htm
excerpts:
Alert kept up on volcano
THE stage two alert on Mount Ulawun will remain in force until authorities
are convinced there is no imminent danger of another eruption.
An update on the volcanic activity by the East New Britain provincial
disaster committee, which is monitoring the situation through the Rabaul
Volcanological Observatory, said the summit activity had quietened down.
But the continuous occurrence of volcanic tremors provided evidence that
the volcano was still active.
West New Britain Governor Clement Nakmai yesterday met with the provincial
executive council, the administration and disaster committee, to discuss
the fate of the 3750 displaced people in care centres at Bakada, Soi and
Kabaya. Officials in Bialla said the immediate concern was to feed those in
care centres.
Topic 2 of 99 [Geo]: Vulcanism
Response 273 of 997: Marcia (MarciaH) * Wed, Oct 11, 2000 (22:29) * 39 lines
Kilauea update
0510 October 8, 2000
Note: Your observer will be attending a meeting in Waikiki
on October 9-11. The next predawn report will be written
on October 12. In the meantime, any important developments
will be reported here as needed.
Kamokuna continues to gobble up all the lava that makes
its way across the coastal flat. This Sunday morning at
0435, the entry was glowing brightly and giving off a
moderate steam plume. Still, the amount of lava entering
the water seems substantially less than that pouring
through the lava tube above Pulama pali. Apparently the
new flow on the coastal flat is inflating and consequently
taking up some of the lava that otherwise would make it
all the way to the coast.
Kamokuna is about 1.5 km west-southwest of Waha`ula and has
been the site of repeated entries over the years. Narrow
streams of lava are trickling over the old sea cliff there,
spaced across a shoreline distance of about 600 m. The mid-
dle of the three benches at Kamokuna is about 360 m wide
and has been the most active for the past several days.
On Pulama pali this morning at 0435, the only glow is from
the long-lived skylight high on the scarp.
The crater of Pu`u `O`o is dark on this cool, blustery
morning.
Volcanic tremor near Pu`u `O`o continues at a weak to
moderate level. Earthquake activity is low across the
island. The tilt at Kilauea summit is rather flat (ac-
tually continuing the long-term slow deflation underway
since the eruption began in 1983), as it is near Pu`u
`O`o and everywhere else along the east rift zone.
Topic 2 of 99 [Geo]: Vulcanism
Response 274 of 997: Marcia (MarciaH) * Tue, Oct 17, 2000 (20:52) * 11 lines
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Piton de la Fournaise eruption
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From: Jean-Louis CHEMINEE
A new eruption, the third in 2000, started at Piton de la Fournaise
(Reunion Island) Oct 12 at 5:05, local time, after a seismic crisis started
at 4:09, local time. This eruption, situated SE of Dolomieu crater flank,
in the Enclos Fouquet, follows 4 weeks of increasing seismicity and ground
deformations.
Topic 2 of 99 [Geo]: Vulcanism
Response 275 of 997: Marcia (MarciaH) * Tue, Oct 17, 2000 (20:55) * 63 lines
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MVO update, Friday, October 6, 2000
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From: Dan Shackelford
Subject: Spine growth, incandescent rockfalls and pyroclastic flows at
Soufriere Hills
For the week ending 6 October, Soufriere Hills displayed spine and dome
growth, small pyroclastic flows and incandescent rockfalls. Somewhat
reduced seismic levels when compared to the previous week,
Following from Montserrat Volcano Observatory, care of Peter Dunkley
:
Report for the period midday, 29 September 2000 to midday, 6 October 2000
Activity at the Soufrière Hills volcano has continued this week with the
summit lava dome continuing to grow.
Clear views of the summit of the volcano were seen on most days of the
week. A large steeply inclined lava spine dominated the eastern part of
the summit region of the dome and changed in size and shape throughout the
week. On the evening of the 30th September the top of the spine had reached
an altitude of 1054 metres, this being the highest measurement taken on the
dome so far. On the morning of 6 October there were several smaller spines.
Observation flights indicate that there has been no new growth on the
western flanks of the dome.
Rockfalls were confined to the eastern side of the dome, where they
contribute to a very broad apron of talus accumulating in the upper reaches
of the Tar River valley. Rockfalls of incandescent material were observed in
this area at night. There were a number of very small pyroclastic flows off
the eastern side of the dome, the largest of which passed down the Tar River
but did not reach the delta. This short-lived but energetic flow occurred on
the morning of the 2nd October and produced a dense, dark ash cloud which
remained at a low level and moved rapidly to the northwest on the prevailing
wind, depositing ash in the Salem area before being swept out to sea.
The level of seismic activity was considerably lower than in the previous
week. The broadband seismic network recorded a total of 169 rockfall
signals, 29 hybrid, 25 long period and 16 volcano-tectonic earthquakes for
the reporting period.
COSPEC measurements indicate an increase in sulphur dioxide emissions
compared with the previous week, with daily average values of 790 and 948
tonnes on the 2nd and 3rd October respectively.
Residents of Montserrat and visitors to the island are advised to tune in to
ZJB Radio for up-to-date information on the status of the volcano. Rockfall
and pyroclastic flow activity is likely to remain at a high level whilst the
dome continues to grow, producing ash clouds which may blow over inhabited
areas if winds are from the south or southeast. Elevated levels of
pyroclastic flow activity may develop very rapidly and could affect any
valleys around the volcano. Ash masks should be worn in ashy conditions or
when you disturb ash. The Belham valley should be avoided during and after
periods of heavy rain and everyone is reminded that access to Plymouth,
Bramble airport and beyond is prohibited. There is a maritime exclusion zone
around the southern part of the island that extends two miles beyond the
coastline from Trant's Bay in the east to Garibaldi Hill on the west coast.
The daytime entry zone remains closed.
12 noon, Friday, 6 October 2000
Topic 2 of 99 [Geo]: Vulcanism
Response 276 of 997: Marcia (MarciaH) * Tue, Oct 24, 2000 (23:02) * 111 lines
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KVERT Information Release; October 17, 2000
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From: Alaska Volcano Observatory
Kamchatkan Volcanic Activity
INFORMATION RELEASE 00-44
Wednesday, October 18, 2000, 12:20 KDT (2320 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Daylight Time, 21 hours ahead of Alaska Daylight Time.
BEZYMIANNY VOLCANO 55o 58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS GREEN.
A thermal anomaly, first observed in satellite images by AVO on September
21, has increased in intensity during the past week. According to AVO
satellite data, a 4 pixel thermal anomaly at Bezymianny was observed in a
nighttime AVHRR image at 07:04 KDT on October 18. One pixel was saturated
at 50 degrees Celsius, and a recovery pixel was also present, indicative of
intense thermal activity. Background temperature values were about -10 to
-15 degrees Celsius. This is the most intense thermal activity that has
been observed since the initial observation of the anomaly on September 21.
No ash plumes or drifting ash clouds have been detected. Thermal anomalies
detected in satellite data have preceded explosive eruptions of Bezymianny
by days to weeks in October 1995, May and December 1997, February 1999, and
March 2000. However, in June 1998, intense thermal activity was not
followed by an explosive event.
Only two small (M0) earthquakes were registered under the volcano during
the past 5 days. On most days, clouds obscured the volcano. On October 16,
weak fumarolic activity was observed.
It is necessary to note that the nearest seismic station ZLN has been out
of order since October 14.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS.
Olga Chubarova David Schneider
Kamchatka Volcanic Eruptions Alaska Volcano Observatory
Response Team, IVGG, Piip Blvd, 9 4200 University Drive
Petropavlovsk-Kamchatsky, 683006, RUSSIA Anchorage, Alaska 99508
E-mail: ochubarova@emsd.iks.ru E-mail: djschneider@usgs.gov
tel. (415-22)59385 907-786-7037
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KVERT Weekly Update, October 20, 2000
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From: Alaska Volcano Observatory
Kamchatkan Volcanic Activity
INFORMATION RELEASE 00-45
Friday, October 20, 2000, 12:00 KDT (2300 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Daylight Time, 21 hours ahead of Alaska Daylight Time.
KLYUCHEVSKAYA GROUP OF VOLCANOES
KLYUCHEVSKOY VOLCANO 56o03'N, 160o39'E; Elevation 4,750 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
During the past week (October 13-19), seismic activity was near
background levels. Shallow earthquakes occurred. On October 13, a
fumarolic plume rose 200 m above the volcano and extended 5 km to the
east. On October 15, weak fumarolic activity was observed. On other days,
clouds obscured the volcano.
BEZYMIANNY VOLCANO 55o58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
A thermal anomaly, first observed in satellite images by AVO on September
21, has increased in intensity and size during the past week.
Only three small (M0) earthquakes were registered under the volcano during
the past week. On most days, clouds obscured the volcano. On October 16,
weak fumarolic activity was observed.
SHEVELUCH VOLCANO 56o38'N, 161o19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
On October 15, weak fumarolic activity was observed. On October 16, a
gas-steam plume rose 350 m above the dome. On other days, clouds obscured
the volcano. Weak continuous volcanic tremor was recorded during the entire
week. At 15:12 KDT on October 14(02:12 UTC), seismic data indicated a
possible gas-ash explosion as a 20-minutes-long series of strong shallow
seismic events occurred. The height of the cloud was estimated on the
basis of the seismicity at ~7,500 m ASL.
KARYMSKY VOLCANO 54o03'N, 159o27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKAYA GROUP OF VOLCANOES, 53o15'N, 158o51'E;
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes is at normal levels.
MUTNOVSKAYA GROUP OF VOLCANOES
GORELY VOLCANO, 52o33'N, 158o02'E, Elevation 1,828M
MUTNOVSKY VOLCANO, 52o27'N, 158o12'E, Elevation 2,324 M.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On October 14-15 and 17-18, both of volcanoes were quiet. On other days,
clouds obscured the volcanoes. On October 13-16, microseismic signals were
registered on seismic station GRL.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS.
Olga Chubarova David Schneider
Kamchatka Volcanic Eruptions Alaska Volcano Observatory
Response Team, IVGG, Piip Blvd, 9 4200 University Drive
Petropavlovsk-Kamchatsky, 683006, RUSSIA Anchorage, Alaska 99508
E-mail: ochubarova@emsd.iks.ru E-mail: djschneider@usgs.gov
tel. (415-22)59385 907-786-7037
Topic 2 of 99 [Geo]: Vulcanism
Response 277 of 997: Marcia (MarciaH) * Fri, Oct 27, 2000 (23:12) * 92 lines
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Indonesian Volcano Update, 10-16 October
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For the week ending 16 October, the Indonesian volcanoes Slamet and Semeru
showed a decrease in the level of their activity, whereas the volcanoes Api
Siau (lava flow and avalanches) and Merapi (earthquake swarm and deep
earthquakes) showed a significant increase in their activities. Kerinci,
Krakatau, Lokon-Empung and Soputan remained at about the same level of activity.
From: http://www.vsi.dpe.go.id/news/index.html
Weekly Report No. 585 - 10-16 October 2000
Kerinci
Jambi, Sumatera; 1°41.5' S, 101°16' E, summit elev. 3,800 m
Ash plume still occurred and dominating at Kerinci activity. The color was
commonly in white thin-thick, rose up to 400 m height. Seismicity was still
dominated by small explosion earthquakes and increased in volcanic
earthquake. Deep volcanic (A) 3 events, shallow volcanic (B) 1 event, small
explosion 261 events, and 3 events of tectonic earthquake.
The alert level of Kerinci volcano is in level 2.
Anak Krakatau
Sunda strait; 6°6'5.8" S, 105°25'22.3" E
Krakatau activity more quite during the week. There was no thundering sound
from the volcano. Seismograph continued to record small explosion
earthquake but the number decreased over last week. The complete seismicity
during the week were 24 events of small explosion and 1 event of tectonic
earthquake.
Anak Krakatau volcano is in level 2.
Slamet
Central Java; 7°14.30' S,109°12.30' E
During the week Slamet activity showed a significant decreasing. It was
represent from both visual and instrumental monitoring. Ash plume rose
about 50-100 m height and seismograph only record a continuous tremor with
the amplitude of 0.15-7 mm.
Slamet volcano is in level 2.
Semeru
East Java; 8°6.50' S, 112°55' E
From seismograph recording Semeru activity indicated a major decreasing
this week. The number of seismicity was decreased over the previous week.
Pyroclastic flow occurred once time. Detail seismicity were deep volcanic
(A) 1 event, shallow volcanic (B) 3 events, explosion 592 events,
pyroclastic 1 event, avalanche 41 events, and 9 events of tectonic
earthquake.
The alert level of Semeru volcano is in level 2.
Karangetang
Siau island; 2°47' N, 125°29' E
Karangetang activity showed a major increasing within this week. Main
crater and crater II continued to ejecting white thin-thick ash plume, hit
about 500 m height above the summit. Sometime was heard a thundering sound
from the volcano and night view was observed the red flame up to 75 m.
On 14 October 2000, at 18.40 WITA (local time) was observed glowing lava
which flowed away 100 m distance to the Nenitu river. Meanwhile the
avalanche hit about 1000 m.
Seismograph recorded a significant increasing of deep volcanic (A) and
small explosion earthquake. Complete data listed as follow : deep volcanic
(A) 36 events, shallow volcanic (B) 1 event, small explosion 145 events,
tectonic 11 events, and a continuous of tremor earthquake with the
amplitude of 0.5-23 mm.
Karangetang volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
Based on visual observation there is no major change in Lokon activity. But
the volcano was still ejecting the white thin-thick ash plume that hit
about 250 m height. Red flame with the radiation of 25 m was shown from the
crater. Seismograph was recorded 6 events of deep volcanic (A) and 22
events of tectonic earthquake.
Lokon volcano is in level 2.
Soputan
North Sulawesi; 1°6.5' N, 124°43' E
There is major change in Soputan activity during this week. Seismicity was
dominated by avalanche earthquake but recorded 1 of deep volcanic
earthquake. Complete seismicity were deep volcanic (A) 1 event, tectonic 18
events, and 242 events of avalanche earthquake.
Soputan volcano is in level 2.
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Although visual observation was obscured by the haze, Merapi activity
showed a significant increasing. Seismograph recorded a significant swarm
and deep volcanic earthquake during this week. Meanwhile, seismicity was
still dominated by superficial earthquakes such as multiphase and avalanche
earthquake.
Merapi volcano is in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 278 of 997: Marcia (MarciaH) * Fri, Oct 27, 2000 (23:16) * 34 lines
I know this man with the JPL initials. VERY well, indeed. I also know Jim Griggs! We even share the same ISP!
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Year 2001 IAVCEI Volcano Calendars
************************************
From: John Lockwood
Dear Volcanophile Friends:
Brian Hausback and Steve McNutt's superb Labor of Love, the Sacramento
Volcanological Society's "2001 IAVCEI Volcano Calendars" (and other
calendars focusing on Hawaiian Volcanic activity) are now available at the
HAWAIIAN VOLCANO STORE (http://www.volcanostore.com).
Please pardon the delay in presenting these, but the Store has undergone a
change of ownership and management, and has been completely
redesigned. Jim Griggs of Volcano, Hawaii, well-known for his photographs
of Hawaiian volcanic activity, is the new Proprietor of the Store, and is
now responsible for carrying the shop to new heights!. Marti and I have
enjoyed filling thousands of orders for you over the past four years, but
have decided that we really weren't cut out to be "shopkeepers". There are
lots of volcanoes "out there", and so long as our legs stay strong, we
intend to make them our main focus in life - both for fun and work!
Jim and his colleagues will be greatly expanding the Store line of
volcano-related products in the near future, and they look forward to
hearing from you as to new quality products you'd like to see stocked. As
before, the Store will be offering most products to you at below retail
cost. Please stop by and see the changes!
Aloha 'Oukou,
Jack & Marti
Topic 2 of 99 [Geo]: Vulcanism
Response 279 of 997: Marcia (MarciaH) * Fri, Oct 27, 2000 (23:28) * 43 lines
Smithsonian Institution
Bulletin of the Global Volcanism Network
Volume 25, Number 8, August 2000
VOLCANOES
Arenal (Costa Rica) Maps, photos, and seismic data on the 23 August eruption
Poas (Costa Rica) Fumarolic activity and increased seismicity during
JanuaryJune 2000
Shishaldin (Alaska) Thermal anomaly and small explosions on 11 August
Shiveluch (Kamchatka) Fumarolic plume, multiple gasash explosions, and
partial dome collapses
Bandai (Japan) Unprecedented increase in seismicity during 1416 August
Komagatake (Japan) Small eruptions on 4 and 28 September, the first since
October 1998
Aoba (Vanuatu) Increase in temperature and acidity at Lake Voui during
AprilAugust 2000
Ulawun (Papua New Guinea) Eruption on 29 September causes the evacuation of
nearby towns
Rotorua (New Zealand) Smallscale hydrothermal eruption on 18 September
White Island (New Zealand) Ashandsteam emissions accompanied by magmatic
eruption
Stromboli (Italy) Lowtomoderate eruptive activity JanuarySeptember 2000
EARTHQUAKES
Santa Cruz Islands (Mw 6.7) 3 August; Sakhalin Island (Mw 6.8) 4 August;
Kermadec Islands (Mw 6.7) 15 August; Indonesia (Ms 6.8) 28 August
Editors: Rick Wunderman and Edward Venzke
Editorial Assistants: Gari Mayberry, Luke Jensen, Alicia Arroyo, David
Charvonia, and Jacquelyn Gluck
Topic 2 of 99 [Geo]: Vulcanism
Response 280 of 997: Marcia (MarciaH) * Sat, Oct 28, 2000 (23:53) * 3 lines
For an idea of how the Island of Hawaii is made of various volcanoes:
Topic 2 of 99 [Geo]: Vulcanism
Response 281 of 997: Marcia (MarciaH) * Sat, Oct 28, 2000 (23:54) * 33 lines
Hawaiian Meaning
The Hawaiian name "Kilauea" means "spewing" or "much spreading," apparently in
reference to the lava flows that it erupts.
Most Recent Eruption
Continuous since January 3, 1983
Number of Historical Eruptions
61, not counting the continuous lava-lake activity in Halema`uma`u crater
Summit Caldera
The caldera itself has no Hawaiian name other than Kilauea but houses the famous
crater, Halema`uma`u; "hale" is a house, "ma`uma`u" a type of fern. Kamapua`a, a
jilted suitor of Pele, is said to have built a house of ferns over Halema`uma`u to keep
Pele from escaping her home and causing eruptions. The ploy failed.
Dimension: 6 x 6 km (outermost faults), 3 x 5 km (main depression)
Depth: 165 m deep
Age: probably several incremental collapses 500-210 years ago
Oldest Dated Rocks
23,000 years old
Estimated Age of Earliest Subaerial Eruptions
50,000-100,000 years
Estimated Age of First Eruption of Kilauea
300,000-600,000 years before present
Hawaiian Volcano Stage
Shield-forming stage
Topic 2 of 99 [Geo]: Vulcanism
Response 282 of 997: Marcia (MarciaH) * Sat, Oct 28, 2000 (23:57) * 3 lines
Close-up of where the erutpion is taking place:
Topic 2 of 99 [Geo]: Vulcanism
Response 283 of 997: Marcia (MarciaH) * Sun, Oct 29, 2000 (00:04) * 27 lines
In our latest effort to improve the volcano-monitoring instruments on Mauna Loa and Kilauea, we
have just completed the installation of the most sensitive instruments available for monitoring the
strain deep beneath the surface of a volcano. Three holes more than 100 m deep were drilled into
Mauna Loa, and an existing deep hole in Kilauea's summit area was also used. In each hole were
installed an ultra-sensitive strainmeter and a seismic package consisting of a three-component
broadband seismometer and a strong-motion sensor. Currently the installations are being tested
and modified where necessary. Later this year, a borehole tiltmeter may be added high in each
hole. Once all of this is completed, the state-of-the-art instrumentation will radio data to the
Hawaiian Volcano Observatory in real time and make possible the early detection and tracking of
events occurring deep within Mauna Loa and Kilauea with unprecedented clarity.
The instruments were installed in a collaboration between USGS scientists from HVO and the
Earthquake Hazards Program (Menlo Park, CA) and scientists from the Center for the Study of
Active Volcanoes (CSAV), University of Hawai`i in Hilo. The Carnegie Institution of Washington
- Department of Terrestrial Magnetism manufactured the instruments and advised us in their
installation. Funding for the drilling came through a grant from the Department of Defense via
NASA.
The project received invaluable assistance from Hawai`i Volcanoes National Park, the Mauna
Loa Observatory, the Mauna Loa High Altitude Observatory, and Hokukano Ranch. The holes
on Mauna Loa were drilled by DOSECC (Drilling, Observation, and Sampling of the Earth's
Continental Crust, Inc.).
More... http://hvo.wr.usgs.gov/howwork/strain/
Topic 2 of 99 [Geo]: Vulcanism
Response 284 of 997: Marcia (MarciaH) * Tue, Oct 31, 2000 (19:32) * 90 lines
*********************************************
KVERT Information Release; October 29, 2000
*********************************************
Kamchatkan Volcanic Activity
INFORMATION RELEASE 00-47
Monday, October 30, 2000, 10:30 KST (2230 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Standard Time, 21 hours ahead of Alaska Standard Time.
KLYUCHEVSKAYA GROUP OF VOLCANOES
BEZYMIANNY VOLCANO 55o58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS YELLOW.
The number and energy of shallow earthquakes has continued to increase.
Seismic data indicate that (hot?) rock avalanches have rolled down from the
dome. Beginning at 01:15 KDT on October 28, energy from B-type earthquakes
increased. A thermal anomaly, first observed in satellite images by AVO on
September 21, continued to be detected (8 pixels with 4 pixel at saturation
temperature of 50 degrees Celsius in the satellite image at 06:32 KST on
October 30). At 08:10 KST on October 30, a gas-steam plume rose 1000 m
above the volcano and extended to the northeast. The previous few days, the
volcano was obscured by clouds. Unfortunately, KVERT has incomplete seismic
data because of unstable
seismic stations operation.
*********************************************
KVERT Update, Friday, October 27, 2000
*********************************************
Kamchatkan Volcanic Activity
INFORMATION RELEASE 00-46
Friday, October 27, 2000, 13:00 KDT (0000 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Daylight Time, 21 hours ahead of Alaska Daylight Time.
KLYUCHEVSKAYA GROUP OF VOLCANOES; KLYUCHEVSKOY VOLCANO 56o03'N, 160o39'E;
Elevation 4,750 m. CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN. During the
past week (October 20-26), seismic activity was near
background levels. Shallow earthquakes occurred. On October 23 and 25, weak
fumarolic activity was observed. On other days, clouds obscured the volcano.
BEZYMIANNY VOLCANO 55o58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
A thermal anomaly, first observed in satellite images by AVO on September
21, continued to be detected (4 pixels with one pixel at saturation
temperature of 50oC). On October 21, a fumarolic plume rose 50 m above the
volcano and extended to the east. On October 25, a fumarolic plume rose 50
m above the volcano and extended 20 km to the south. On other days, clouds
obscured the volcano. A few shallow earthquakes (M0) per day wee
registered under the volcano. Since October 25, seismic data indicate that
(hot?) rock avalanches have rolled down from the dome. From 20:40 to 21:00
KDT on October 26, spasmodic volcanic tremor was registered.
Unfortunately, KVERT has not complete seismic data because of unstable
seismic stations operation.
SHEVELUCH VOLCANO 56o38'N, 161o19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
On October 25, a gas-steam plume rose 200 m above the dome. On other days,
clouds obscured the volcano. Weak continuous volcanic tremor and small
shallow earthquakes were recorded on October 22-23. At 22:29 KDT on
October 14(09:29 UTC) and at 21:14 KDT on October 26, seismic data
indicated possible gas-ash explosions as shallow seismic events occurred.
The height of the cloud was estimated on the basis of the seismicity at
~4,000 m ASL. Since 01:00 on October 26, volcanic tremor continued to be
recorded.
KARYMSKY VOLCANO 54o03'N, 159o27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels. On October 25, weak local
events were registered and a small pyroclastic flow possibly occurred.
AVACHINSKAYA GROUP OF VOLCANOES, 53o15'N, 158o51'E;
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes is at normal levels.
MUTNOVSKAYA GROUP OF VOLCANOES: GORELY VOLCANO, 52o33'N, 158o02'E,
Elevation 1,828M; MUTNOVSKY VOLCANO, 52o27'N,158o12'E, Elev. 2,324 M.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On October 20 and 25,both volcanoes were quiet. On October 24, a gas-steam
plume rose 700 m above the Mutnovsky volcano. On other days, clouds
obscured the volcanoes. Since October 24, no microseismic signals were
registered on seismic station GRL.
Topic 2 of 99 [Geo]: Vulcanism
Response 285 of 997: Marcia (MarciaH) * Tue, Oct 31, 2000 (21:15) * 55 lines
****************************
Popocatepetl, Mexico
****************************
Subject: Renewed dome growth and explosive activity at Popocatepetl.
New dome growth is occurring at Mexico's Popocatepetl volcano. A rather
vigorous eruption on 29 October at 1710 lofted an impressive ash cloud to
~3 km above the crater, with ashfalls to the ENE. This event followed
several days of increased seismicity which is believed indicative of new
tholoid growth.
According to http://www.ssd.noaa.gov/VAAC/messages.html, a "hot spot" was
seen on satellite imagery for this event as well.
From: http://www.cenapred.unam.mx/cgi-bin/popo/reportes/ultrep.cgi
********************************************
KVERT Information Release, October 30, 2000
********************************************
From: Alaska Volcano Observatory
Kamchatkan Volcanic Activity
INFORMATION RELEASE 00-48
Tuesday, October 31, 2000, 11:00 KST (2300 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Standard Time, 21 hours ahead of Alaska Standard Time.
KLYUCHEVSKAYA GROUP OF VOLCANOES
BEZYMIANNY VOLCANO 55o58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Beginning at 23:00 KST on October 30, seismic activity increased. The
most intense seismic activity was registered from 01:46 to 02:46 KST on
October 31 (from 13:46 to 14:15 GMT on October 30). The seismic record did
not show a distinct explosive event.
AVHRR satellite data from AVO showed an ash eruption at Bezymianny. The
image from October 30 at 1700 GMT showed an ash plume extending from the
volcano to the southeast (azimuth 110-115 degrees) for 55 km (~30 nautical
miles). An image from October 30 at 1800 GMT, showed the ash plume
extending for about 80 km (45 nautical miles) to the southeast (azimuth
110-115 degrees). It was not possible to estimate the height of the ash
plume. Wind data from Petropavlovsk-Kamchatsky at 1200 GMT showed that the
wind was generally out of the west at all altitudes, so it was not possible
to estimate height based on cloud movement. According to visual report
from Koziyrevsk at 07:30 KST on October 31, a gas-steam plume rose 1500 m
above the volcano and extended to the southeast.
Seismic activity at the volcano continues. Seismic data analysis implies
that the volcanic activity may increase and another ash eruption can occur
with little warning.
Topic 2 of 99 [Geo]: Vulcanism
Response 286 of 997: Marcia (MarciaH) * Wed, Nov 1, 2000 (20:10) * 56 lines
**********************************************
MVO Weekly Activity Report, 27 October 2000
**********************************************
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 20 October 2000 to midday, 27 October 2000
Activity at the Soufrière Hills volcano has continued at an elevated level
this week.
Clear views of the summit of the volcano were seen on most days. Growth
of the lava dome continued on the east side of summit region where
spectacular incandescence was observed at night. Growth was dominated by
the semi-continuous extrusion of a broad lava spine inclined at a steep
angle upwards towards the east. At various stages large portions of the
spine broke off, but growth generally kept pace with disintegration as fresh
material continued to be extruded. On the 25h October the top of the spine
had an altitude of 1039 metres, and the general height of the surrounding
summit region of the active lobe had an altitude of around 1000 metres.
Observation flights indicate that there has been no new growth on the
western and northern flanks of the dome.
Rockfalls were confined to the eastern side of the dome, where they
contribute to the talus fan accumulating in the upper reaches of the Tar
River valley. The talus is beginning to bury the remnant buttress of older
dome material on the north-east flank which formed during the 1995-98 phase
of growth. Rockfalls produced small ash clouds which drifted
north-westwards on the prevailing wind and gave rise to very light ash falls
in the populated areas of the island. Rockfalls of incandescent material
were observed at night.
The level of seismic activity has been much lower than in previous weeks.
The broadband seismic network recorded a total of 214 rockfall signals, 9
hybrid, 35 long period and 4 volcano-tectonic earthquakes for the
reporting period. Some of the rockfalls had long period precursor signals
characteristic of small explosive events.
COSPEC measurements indicate daily average sulphur dioxide emissions of
235, 925 and 2252 tonnes on the 23th, 24th and 26th October respectively.
Residents of Montserrat and visitors to the island are advised to tune in to
ZJB Radio for up-to-date information on the status of the volcano. Rockfall
and pyroclastic flow activity is likely to remain at a high level whilst the
dome continues to grow, producing ash clouds which may blow over inhabited
areas if winds are from the south or southeast. Elevated levels of
pyroclastic flow activity may develop very rapidly and could affect any
valleys around the volcano. Ash masks should be worn in ashy conditions or
when you disturb ash. The Belham valley should be avoided during and after
periods of heavy rain and everyone is reminded that access to Plymouth,
Bramble airport and beyond is prohibited. There is a maritime exclusion zone
around the southern part of the island that extends two miles beyond the
coastline from Trant's Bay in the east to Garibaldi Hill on the west coast.
The daytime entry zone remains closed.
12 noon, Friday, 27 October 2000
Topic 2 of 99 [Geo]: Vulcanism
Response 287 of 997: Marcia (MarciaH) * Sat, Nov 4, 2000 (21:26) * 30 lines
Mexico on Alert Over Volcano Popocatepetl Activity
MEXICO CITY (Reuters) - Mexican authorities were on alert
on Saturday for a possible strong exhalation of ash and smoke
by the volcano Popocatepetl, which lies 38 miles from Mexico
City, due to an increase in volcanic activity.
"We have increased our preventive measures and increased
the radius of security to 10 km (6.2 miles). Previously the
radius was 7 km (4.3 miles) from the crater," a spokesman for
the National Center for Prevention of Disasters (Cenapred) told
Reuters.
However, the spokesman said the activity of the volcano,
known as "The Smoking Mountain" in the indigenous Nahuatl
language, had diminished since Saturday morning after earlier
increasing.
After the volcano's activity picked up on Friday, the
center decided to step up the state of alert to "yellow phase
three" from "yellow phase two," which means preventive measures
are reinforced among the local population.
"This does not in any way imply a possible evacuation," the
spokesman said.
Recently, Popocatepetl, 17,884 feet high, has been
registering strong exhalations. The volcano sporadically
exhaled small amounts of steam and gases on Saturday.
Popocatepetl, active for the past six years, in 1997 spewed
up a spout of ash 11.2 miles into the sky, causing eye
irritation and respiratory problems among thousands of people
living nearby.
Topic 2 of 99 [Geo]: Vulcanism
Response 288 of 997: Marcia (MarciaH) * Sun, Nov 5, 2000 (18:56) * 49 lines
***********************************************
Montserrat Volcano Observatory: Weekly Report
***********************************************
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 27 October 2000 to midday, 3 November 2000
Activity at the Soufrière Hills volcano has continued at an elevated level
this week.
Growth of the lava dome has continued on the east side of summit region.
Clear views of the volcano were seen on the last three days of the
reporting period when the summit region of the dome was occupied by a
cluster of toppled spine fragments, the highest of which had an altitude of
1013 metres. Observation flights indicate that there has been no new growth
on the western and northern flanks of the dome.
Rockfalls were confined to the eastern side of the dome, where they
contribute to the talus fan accumulating in the upper reaches of the Tar
River valley. The talus has continued to encroach upon the remnant
buttress of older dome material on the north-east flank which formed during
the 1995-98 phase of growth. Rockfalls produced small ash clouds which
drifted north-westwards on the prevailing wind and gave rise to very light
ash falls in the populated areas of the island. Rockfalls of incandescent
material were observed at night.
The level of seismic activity was slightly lower than in the previous week.
The broadband seismic network recorded a total of 146 rockfall signals, 20
hybrid, 19 long period and 3 volcano-tectonic earthquakes for the
reporting period. A few rockfalls had long period precursor signals
characteristic of small explosive events.
Residents of Montserrat and visitors to the island are advised to tune in to
ZJB Radio for up-to-date information on the status of the volcano. Rockfall
and pyroclastic flow activity is likely to remain at a high level whilst the
dome continues to grow, producing ash clouds which may blow over inhabited
areas if winds are from the south or southeast. Elevated levels of
pyroclastic flow activity may develop very rapidly and could affect any
valleys around the volcano. Ash masks should be worn in ashy conditions or
when you disturb ash. The Belham valley should be avoided during and after
periods of heavy rain and everyone is reminded that access to Plymouth,
Bramble airport and beyond is prohibited. There is a maritime exclusion zone
around the southern part of the island that extends two miles beyond the
coastline from Trant's Bay in the east to Garibaldi Hill on the west coast.
The daytime entry zone remains closed.
12 noon, Friday, 3 November 2000
Topic 2 of 99 [Geo]: Vulcanism
Response 289 of 997: Marcia (MarciaH) * Sun, Nov 5, 2000 (18:58) * 92 lines
************************************
KVERT Update, Friday, Nov. 3, 2000
************************************
From: Alaska Volcano Observatory
Kamchatkan Volcanic Activity
INFORMATION RELEASE 00-49
Friday, November 3, 2000, 18:00 KST (0600 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are either in Kamchatkan Daylight Time, 21 hours ahead of Alaska Daylight
Time or Kamchatkan Standard Time, also 21 hours ahead of Anchorage.
KLYUCHEVSKAYA GROUP OF VOLCANOES;
KLYUCHEVSKOY VOLCANO 56o03'N, 160o39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
During the past week (October 27-November 2), seismic activity was near
background levels. On October 29-31, a gas-steam plume rose 400-700 m above
the volcano and extended 5 km to the southwest and sourtheast on
October30-31. On other days, clouds obscured the volcano.
BEZYMIANNY VOLCANO 55o58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS ORANGE.
On October 27-29, the volcano was obscured by clouds. The number and
energy of shallow earthquakes continues to increase. Seismic data indicate
that (hot?) rock avalanches have rolled down from the dome. Beginning at
01:15 KDT on October 28, energy from B-type earthquakes increased. No ash
plumes or drifting clouds was observed at 07:30 and 15:30 KST on October 30
satellite images. At 08:10 KST on October 30, a gas-steam plume rose 1 km
above the volcano and extended to the northeast. Beginning at 23:00 KST on
October 30, a significant increase in seismicity occurred. The most
intense seismic activity was registered from 01:46 to 02:15 KST on October
31 (132:46 to 14:15 UTC on October30). The seismic record did not5 show a
distinct explosive event. AVHRR satellite data from AVO showed an ash
eruption at the volcano. The image from October 31 at 05:00 KST (Oct. 30
at 1700 UTC), showed an ash plume extending from the volcano to the
southeast for 55 km. An image from Oct. 31 at 06:00 KST (Oct. 30 at 1800
UTC), showed the ash plume extending for about 80 km to the southeast. It
was not possible to estimate the height of the ash plume. According to
visual reports from Koziyrevsk at 07:30 KST on Oct. 31, a gas-steam plume
rose 1500 m above the volcano and extended to the southeast. At 12:10 KST,
an ash-poor plume rose 3 km above the volcano, at 13:30 a gas-steam plume
rose 1 km, and at 15:15 KST, a gas-steam plume rose 2 km above the volcano.
An image from Oct. 31 at 15:06 KST (0306, Oct. 31 UTC), showed an ash
plume extended for about 40 km to the northeast that might have a minor
amount of ash. A larger, diffuse cloud was seen off the east coast of
Kamchatka that seemed to be continuous with the more distinct plume coming
from the volcano. It extended for about 250 km to the southeast but did
not appear to contain an ash component.
The most intensive seismicity was registered from 03:20 to 04:00 KST and at
06:26 KST on Nov. 2. The satellite image at 06:26 KST on Nov. 2 showed an
ash plume extended 50 km west of the volcano, then 130 km to the southwest.
The height of the plume was ~ 6,500 m ASL. According to visual reports
from Koziyrevsk at 08:00 KST on Nov. 2, a gas-steam plume rose 1000 m above
the volcano and extended to the southwest; at 08:42 KST, an ash-gas plume
rose 1500 m above the volcano and extended to the southwest. Beginning at
12:00 KST on Nov. 2, seismic activity began to decrease. A satellite image
at 16:21 on Nov. 2 revealed a 231 km long ash plume approximately 270 km
southwest of the Bezymianny summit, centered within the lower third of the
Kamchatkan Peninsula. The satellite image at 16:50 revealed a 250 km long
ash plume ~ 300 km southwest of the Bezymianny summit. An image from Nov.
3 at 06:18 KST (1818 UTC, Nov 2), showed the plume extending for ~ 30 km to
the southeast. According to visual reports from Koziyrevsk at 13:55 KST on
Nov. 3, a gas-steam plume rose 1000 m above the volcano.
SHEVELUCH VOLCANO 56o38'N, 161o19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
On October 29, a gas-steam plume rose 400 m above the dome. On Oct. 31,
Nov. 1, a powerful gas-steam plume rose 700 m above the dome and extended
5 km to the northwest and east on October 30-31. On other days, clouds
obscured the volcano. At 22:29 KDT on October 14(09:29 UTC) and at 15:20
KDT on October 27 (0220 UTC) and at 17:11 KDT on Oct. 28, seismic data
indicated possible gas-ash explosions as shallow seismic events occurred.
The height of the cloud was estimated on the basis of the seismicity at
~4,000-4,500 m ASL.
KARYMSKY VOLCANO 54o03'N, 159o27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKAYA GROUP OF VOLCANOES, 53o15'N, 158o51'E;
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes is at normal levels.
MUTNOVSKAYA GROUP OF VOLCANOES: GORELY VOLCANO, 52o33'N, 158o02'E,
Elevation 1,828M; MUTNOVSKY VOLCANO, 52o27'N,158o12'E, Elev. 2,324 M.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
Both volcanoes were quiet.
Topic 2 of 99 [Geo]: Vulcanism
Response 290 of 997: Marcia (MarciaH) * Mon, Nov 6, 2000 (20:44) * 22 lines
Monday, November 6, 2000
Two hikers found dead atlava flow The Volcanoes Park hikers had severe burns; cause of death is unknown
By Rod Thompson
Star-Bulletin
HAWAII VOLCANOES NATIONAL PARK -- Two hikers were found dead of unknown causes about four miles from
the end of Chain of Craters Road at midday yesterday, according to a park ranger at Hawaii Volcanoes National Park.
Their names were withheld pending notification of their next of kin.
The two, a man and a woman, had apparently walked across a series of lava flows that had been deposited in the area in
the last decade. They were found near where a current lava flow enters the ocean, said ranger Doug Lentz.
Rangers were notified about the bodies by a cell phone call at about 1:30 p.m., Lentz said. The park used a private
helicopter to fly rangers to the scene, and the bodies were retrieved by a Hawaii County helicopter.
Hiking to the lava flow is permitted, but signs in the immediate area warn not to go farther, Lentz said. Officials at the park
were not immediately clear on where the bodies were.
The park advises anyone hiking in the area to have sturdy boots, lots of drinking water, protection from sun and rain, and
flashlights. Park officials had no information on how the hikers were equipped.
Lentz said the hikers had suffered severe burns but were fully clothed, so it was difficult to determine the extent of their
burns. They also had cuts and bruises on their hands, knees and heads.
They were found on high ground, not down on a "bench" of fresh lava at the water's edge, where signs prohibit hiking, Lentz
said.
"They were up where the general public is allowed to be."
An autopsy will be done to determine cause of death, he said.
Topic 2 of 99 [Geo]: Vulcanism
Response 291 of 997: (sprin5) * Tue, Nov 7, 2000 (07:40) * 1 lines
Strange, no obvious cause. Could it have beent he fumes or heat?
Topic 2 of 99 [Geo]: Vulcanism
Response 292 of 997: Marcia (MarciaH) * Tue, Nov 7, 2000 (12:36) * 1 lines
I've been where they were found and no reason for them to be so badly burnt. Scratches and abrasions are common if you fall out there on the sharp new flows, but not dangerous in that area. The police say it appears there was no foul play. However, how else do they explain these inconsistencies. I'll keep you posted!
Topic 2 of 99 [Geo]: Vulcanism
Response 293 of 997: Cheryl (CherylB) * Tue, Nov 7, 2000 (15:52) * 1 lines
Could they have been on the beach and then climbed higher on the flow?
Topic 2 of 99 [Geo]: Vulcanism
Response 294 of 997: Marcia (MarciaH) * Tue, Nov 7, 2000 (16:11) * 2 lines
How did they bet so badly burnt?? Surely they could not have moved from where that happened to the place they were found. There is more to this than meets the eye...there are no beaches along there...just unstable cliffs
Topic 2 of 99 [Geo]: Vulcanism
Response 295 of 997: Cheryl (CherylB) * Tue, Nov 7, 2000 (16:12) * 1 lines
A real mystery. It seems very strange.
Topic 2 of 99 [Geo]: Vulcanism
Response 296 of 997: Marcia (MarciaH) * Fri, Nov 10, 2000 (19:06) * 38 lines
**********************************************
New GVP/USGS Weekly Volcanic Activity Report
**********************************************
From: Gari Mayberry
The Smithsonian's Global Volcanism Program and the US Geological Survey's
Volcano Hazard Program have collaborated to create the Weekly Volcanic
Activity Report, an online summary of global volcanic activity on a weekly
basis that can be accessed via the Global Volcanism Program’s website at
http://www.volcano.si.edu/gvp/ (under Preliminary Notices) or the USGS
Volcano Hazard Program’s website at http://volcanoes.usgs.gov/.
The Weekly Volcanic Activity Report consists of:
· Brief summaries of current volcanic activity with links to the
information sources and to definitions for technical terms in the USGS
photoglossary
· Background information about the reported volcanoes compiled by Global
Volcanism Program staff
· Maps that highlight the location of the reported volcanoes in reference
to geographical features and other volcanoes in the region
· An archive of the weekly reports sorted by volcano and date
· A link to a new USGS web page that provides current updates for US and
Russian volcanoes
· And links to more comprehensive reports that are published monthly in the
Bulletin of the Global Volcanism Network
*******************************************************************
Gari Mayberry
USGS/Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Phone: (202) 357-2618 Fax: (202) 357-2476
mayberry@volcano.si.edu
*******************************************************************
Topic 2 of 99 [Geo]: Vulcanism
Response 297 of 997: Marcia (MarciaH) * Wed, Nov 15, 2000 (11:09) * 3 lines
Update on the two people found dead on the lava flow:
Bodies not burned. Officials awaiting toxicology results.
Topic 2 of 99 [Geo]: Vulcanism
Response 298 of 997: Marcia (MarciaH) * Thu, Nov 16, 2000 (21:42) * 14 lines
****************
Kilauea Update
****************
0555 November 16, 2000
If rain washes air, we have the cleanest on the planet this morning. That allows the glow at Kamokuna to be particularly intense, and the skylight high on Pulama pali gleams like a jewel at 0505.
The heavy rain obscures all views of the crater of Pu`u `O`o this Thursday morning.
Volcanic tremor near Pu`u `O`o remains at a moderate level.
Earthquake activity is low across the island. The tilt-
meters at Kilauea's summit and along the east rift zone
are now showing flat signals, except for several hours last night, when the giant earthquake in New Ireland caused slow, peak-to-peak oscillations at Kilauea's summit amounting to more than 12 microradians. Alarms at two tiltmeters were set off by the large and rapid tilts.
Topic 2 of 99 [Geo]: Vulcanism
Response 299 of 997: Mike Griggs (mikeg) * Fri, Nov 17, 2000 (22:53) * 5 lines
I've visited two volcanoes this year: Mount Teide on Tenerife in the Canary Islands this September and then Mount Fuji on Japan just last week. My friend and I drove up and over Tiede, about 2500m (about 8-9000 feet) in a tiny little 1.0 litre rental car...a most nerve-wracking experience! The view was fantastic, though. As close to a feeling of alien landscape as I've ever experienced. There were huge great lava fields that were just incredible. Maybe I'll buy a scanner, scan some photos and post them here.
Last week on Mount Fuji was great. Went up in a coach tour this time, which was more relaxing. The top of Fuji is usually obscured by cloud, but once we'd reached the visitors centre we were above the cloud. The view was *incredible*. Absolutely no cloud except for a 'hat' of cloud that flew around the caldera at high-speed. I have never seen that before. I guess it must be due to convection currents of some kind coming out of the volcano (it's only dormant, not exctint). I took loads of photos of that, so I'm hoping they will come out.
I like volcanoes :-)
Topic 2 of 99 [Geo]: Vulcanism
Response 300 of 997: Mike Griggs (mikeg) * Fri, Nov 17, 2000 (22:57) * 1 lines
Shame I can't spell extinct, though...
Topic 2 of 99 [Geo]: Vulcanism
Response 301 of 997: Marcia (MarciaH) * Fri, Nov 17, 2000 (23:52) * 3 lines
Hey, Mike!!! Remember Mauna Loa? Didn't you do a bit of remote theorizing about when we punch though the crust? How about Kilauea? It is erupting even as I write this. Aloha!!! Come to Hawaii and see some REAL volcanoes!
Your trip sounds like it was splendid. I am envious like you cannot believe. Amazing about that cloud on Fujiyama. Never heard of that effect. Thanks for sharing. Noe, get thee to a scanner, and if you need space on Spring's hard drive for them, send'um to me and I'll send you the urls for them! Mahalo Nui Loa.
Topic 2 of 99 [Geo]: Vulcanism
Response 302 of 997: Mike Griggs (mikeg) * Sat, Nov 18, 2000 (00:16) * 3 lines
Thanks, Marcia. I think I have a telnet account, but I can't remember the hostname. I tried www.spring.net but that no longer works. I seem to think it was .spring.net
Care to share the hostname? :-)
Topic 2 of 99 [Geo]: Vulcanism
Response 303 of 997: Marcia (MarciaH) * Sat, Nov 18, 2000 (00:53) * 1 lines
unfortunately, since terry changed servers only he and his chief programmer-lurker have access. Ftp I will email to you if you'd like - it is my space on Geo. I hate not having telnet access anymore!!!
Topic 2 of 99 [Geo]: Vulcanism
Response 304 of 997: Mike Griggs (mikeg) * Sat, Nov 18, 2000 (00:56) * 1 lines
Oh...I can't say that I used the telnet access much anyway. Tough luck, I guess! If/when I ever scan them I will happily send them to you.
Topic 2 of 99 [Geo]: Vulcanism
Response 305 of 997: Marcia (MarciaH) * Sat, Nov 18, 2000 (02:33) * 57 lines
Thanks, Mike - I'll be delighted to accommodate resize and so forth and accedit you for your efforts.
*************************************
MVO weekly report, 17 November 2000
*************************************
From: Dr Gill Norton
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 10 November 2000 to midday, 17 November 2000
Activity at the Soufrière Hills volcano has remained at an elevated level
this week with the continued growth of the lava dome on the eastern side of
the summit region.
The level of seismic activity was higher than in the previous week with a
marked increase in the number of long period earthquakes. The broadband
seismic network recorded a total of 207 rockfall signals, 33 hybrid, 144
long period and 7 volcano-tectonic earthquakes for the reporting period.
Clear views of the dome were seen over the period 10 to 13 November. The
summit was still dominated by the extrusion of a broad lava spine inclined
at a steep angle up and towards the east. On 12 November the spine had an
altitude of 1059 metres or 3475 feet. On 13 November it had grown to 1077
metres or 3530 feet, the greatest height measured on the dome throughout the
eruption. Brief views of the dome on the morning of 17 November showed that
the spine had continued to grow still further, although a direct measurement
was not possible.
The number of rockfalls and pyroclastic flows increased towards the end of
the week. A small pyroclastic flow on 15 November entered the upper reaches
of Tyre's Ghaut traveling about 1 km away from the dome. On 17 November,
pyroclastic flow deposits were also noted in the upper reaches of Tuitt's
and White's Ghaut on the north-eastern side of the volcano. This represents
the first new dome material to have traveled down the notch between the
north-eastern and northern lobes of the 1995-98 dome. Most rockfall
activity, however, is still occurring across the eastern face of the dome
above the Tar River. Ash clouds from this activity reached no more than
10,000 feet and mostly traveled to the west across the exclusion zone.
Residents of Montserrat and visitors to the island are advised to tune in to
ZJB Radio for up-to-date information on the status of the volcano. Rockfall
and pyroclastic flow activity is likely to remain at a high level whilst the
dome continues to grow, producing ash clouds which may blow over inhabited
areas if winds are from the south or southeast. Elevated levels of
pyroclastic flow activity may develop very rapidly and could affect any
valleys around the volcano. Ash masks should be worn in ashy conditions or
when you disturb ash. The Belham valley should be avoided during and after
periods of heavy rain and everyone is reminded that access to Plymouth,
Bramble airport and beyond is prohibited. There is a maritime exclusion zone
around the southern part of the island that extends two miles beyond the
coastline from Trant's Bay in the east to Garibaldi Hill on the west coast.
The daytime entry zone remains closed.
12 noon, Friday, 17 November 2000
Topic 2 of 99 [Geo]: Vulcanism
Response 306 of 997: Marcia (MarciaH) * Sat, Nov 18, 2000 (02:49) * 51 lines
EUROPEAN GEOPHYSICAL SOCIETY
XXVI GENERAL ASSEMBLY
NICE 25-30 MARCH 2001
ANNOUNCEMENT AND CALL FOR PAPERS FOR SYMPOSIA ON VOLCANIC HAZARDS
SESSIONS ON VOLCANIC HAZARDS (NH):
NH6.01 Volcanic hazards from explosive eruptions
Convener: Baxter, P.; Co-Convener(s): Macedonio, G.
NH6.02 Parametrization and modelling of lava flows for hazard assessment
Convener: Dingwell, D.B.
NH6.03 Gas emission
Convener: Chiodini, G.; Co-Convener(s): Allard, P.
CO-SPONSORED SESSIONS (SE):
SE13.01 Geophysical and geochemical modelling of unrest
episodes at volcanic areas.
Convener: De Natale, G.; Co-Convener(s): Cornet, F.H., Dahm, T.
SE13.03 Neogene-recent magmatism in the Mediterranean region
Convener: Wilson, M.; Co-Convener(s): Beccaluva, L., Bianchini, G.
SE13.04 Vesuvius and Campi Flegrei - volcanism and volcanic hazards
Convener: Civetta, L.; Co-Convener(s): Orsi, G., Patella, D.
SUBMISSION OF ABSTRACTS
Deadline for receipt of abstracts is 1 DECEMBER 2000
The abstracts must be sent to the EGS Office (EGS@copernicus.org).
Please, send an additional copy to one of the convener of your choice.
Electronic submission is strongly encouraged. Abstracts must be
formatted according to the rules described on the Web page
http://www.copernicus.org/EGS/EGS.html
A LaTeX style and guide is provided on this Web page.
E-mail the abstract as a LaTeX, ASCII, WORD, WordPerfect, Postscript
or PDF file.
Posters with brief oral introduction during the oral session and
extended presentations during the poster sessions are encouraged.
GENERAL INFORMATION AND REGISTRATION
General information on the EGS Assembly and registration forms are
available by browsing the Web page
http://www.copernicus.org/EGS/EGS.html
EGS2001: XXVI General Assembly
Sending an abstract does not mean registration.
Please do not send the registration form to the convener but to the EGS
Office.
PLEASE POST THIS ANNOUNCEMENT AND CIRCULATE IT AMONG COLLEAGUES
More information on the the Scientific Programme, Abstract Submission,
Registration, etc. can be found at the following URL:
http://www.copernicus.org/EGS
Topic 2 of 99 [Geo]: Vulcanism
Response 307 of 997: Marcia (MarciaH) * Sat, Nov 18, 2000 (14:14) * 1 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 308 of 997: Marcia (MarciaH) * Sun, Nov 19, 2000 (14:07) * 105 lines
***************************************
White Island and Ruapehu, New Zealand
***************************************
From: Dan Shackelford
For the week ending 3 November, White Island's vents only emit steam and
gas. No signs of visible unrest at Ruapehu.
For the week ending 10 November, no eruptions at New Zealand volcanoes.
Minor levels of tremor at Ruapehu and weak to moderate degassing at White
Island from its two active vents (9 Nov. observations).
From: http://www.gns.cri.nz/hazardwatch/latest/gweekvo.htm
11/3/00
Eruptive activity has largely ceased at White Island, although the active
vents continue to emit steam and gases. Mt Ruapehu shows no signs of
surface activity. Both White Island and Ruapehu remain at Alert Level 1
(signs of volcano unrest). All other volcanoes are at Alert Level 0
(dormant or quiescent).
11/10/00
No eruptive activity has occurred at any of the volcanoes this week.
Scientists visiting White Island on 9 November found weak to moderate
fumarole activity, with the two active vents producing a white steam and
gas plume. At Ruapehu minor levels of volcanic tremor have been recorded.
Both White Island and Ruapehu remain at Alert Level 1 (signs of volcano
unrest). All other New Zealand volcanoes are at Alert Level 0 (dormant or
quiescent).
**********************************
Piton de la Fournaise, Reunion
**********************************
From: Thomas Staudacher
Regain of activity at Piton de la Fournaise.
An eruption started at Piton de la Fournaise volcano on october 12.
Activity was quite reduced for about 2 weeks, until begin of november and a
new cone was formed, named "Piton Morgabim". Lava flows of 4.5 km formed in
the "Grand Brûlé" on the east of the volcano.
Since November 1rst, tremor constantly increased over 8 days. From november
5, intense fumeroles formed just above the actual crater. Tremor highly
increased over 24 hours and on nov 9, a new well formed 30 m above the
first one. Since 48 hours, eruption tremor is extremely high, but constant
and regular. Piton Morgabim is very active, with a 15 m wide lava lake,
intense degasing and large heavy lava fountains.
New lava flows pf about 2 km lengths formed and partly covered the june
lava flows.
==========================================
Thomas Staudacher, Jean Louis Cheminée
Observatoire Volcanologique du Piton de la Fournaise
Institut de Physique du Globe de Paris
14 RN3, le 27ème
97418 La Plaine des Cafres
La Réunion
*****************************
Colima, Mexico
*****************************
From: Dan Shackelford
Explosive eruption at Mexico's Colima volcano on the evening of 10 November
which produced an ash cloud to ~6 km above sea level, which drifted to ENE.
Following from: http://www.ssd.noaa.gov/VAAC/messages.html
FVXX21 KWBC 110015
VOLCANIC ASH ADVISORY
ISSUED 0015 UTC 11 NOV 2000 BY THE WASHINGTON VAAC
.
COLIMA 00-016 MEXICO 1931N 10337W
.
BACKGROUND: COLIMA MEXICO (1401-04)
SUMMIT HEIGHT 13451 FT (4100 M))
.
SOURCES OF INFORMATION: GOES-8 VISIBLE AND INFRARED AND
MULTISPECTRAL IMAGERY. MEXICO CITY METEOROLOGICAL WATCH
OFFICE.
.
ERUPTION DETAILS: ERUPTION AT 10/2333Z.
.
DETAILS OF ASH CLOUD: THE MEXICO CITY METEOROLOGICAL WATCH
OFFICE REPORTS AN ERUPTION OF COLIMA TO FL200. THE ASH IS
MOVING TOWARDS THE EAST NORTHEAST. SATELLITE IMAGERY THROUGH
10/2345Z SHOWS NO ASH.
.
TRAJECTORY: ACCORDING TO UPPER AIR REPORTS ASH FROM THE SUMMIT
TO FL200 WILL MOVE TOWARDS THE EAST NORTHEAST AT 15 TO 20KTS.
.
OUTLOOK: SEE SIGMETS.
.
THE NEXT MESSAGE WILL BE ISSUED AT 11/0600 UTC.
.
REAL TIME SATELLITE IMAGERY AND VOLCANIC ASH ADVISORIES OFTEN
ACCOMPANIED BY A MAP DEPICTING ASH LOCATION ARE AVAILABLE AT
INTERNET URL ADDRESS
HTTP://WWW.SSD.NOAA.GOV/VAAC/WASHINGTON.HTML
(ALL LOWER CASE EXCEPT /VAAC/)
.
PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS.
.
Topic 2 of 99 [Geo]: Vulcanism
Response 309 of 997: Marcia (MarciaH) * Sun, Nov 19, 2000 (14:12) * 60 lines
*******************************
MVO Weekly Activity Report
*******************************
From: Peter Dunkley
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 3 November 2000 to midday, 10 November 2000
Activity at the Soufrière Hills volcano has remained at an elevated level
this week with the continued growth of the lava dome on the eastern side of
the summit region.
Clear views of the dome were seen on several days during the reporting
period. The summit was dominated by the extrusion of a broad lava spine
inclined at a steep angle upwards towards the east. At various stages parts
of the spine broke off, shedding large blocks on the upper parts of the
dome. On 4th November the spine had an altitude of 1017 metres, but by the
evening of 5th November it was noticeably higher. When next seen on the
morning of 9th November much of the spine had disintegrated and only a broad
basal stump remained. Incandescent glow could be seen on the active part of
the dome at night. Observation flights indicate that there has been no new
growth on the western and northern flanks of the dome.
Rockfalls were confined to the eastern side of the dome, where they continue
to contribute to the broad talus fan accumulating in the upper reaches of
the Tar River valley. Incandescent rockfalls were observed at night.
Heavy rainfall in the early hours of 4th November produced mudflows down the
Belham River. Further heavy rainfall on the afternoon of 8th November
produced mudflows in a number of valleys including the Belham River.
Coinciding with this second period of rainfall, continuous rockfalls and
small pyroclastic flows occurred within the Tar River over a period of
several hours, as minor amounts of material avalanched off the eastern flank
of the lava dome. The pyroclastic flows appear to have been of low energy
and did not reach the Tar River delta. Ash clouds generated by these flows
reached heights of about 6000 feet and drifted northwards on the prevailing
wind.
The level of seismic activity was slightly higher than in the previous week.
The broadband seismic network recorded a total of 252 rockfall signals, 9
hybrid, 11 long period and 3 volcano-tectonic earthquakes for the
reporting period.
Residents of Montserrat and visitors to the island are advised to tune in to
ZJB Radio for up-to-date information on the status of the volcano. Rockfall
and pyroclastic flow activity is likely to remain at a high level whilst the
dome continues to grow, producing ash clouds which may blow over inhabited
areas if winds are from the south or southeast. Elevated levels of
pyroclastic flow activity may develop very rapidly and could affect any
valleys around the volcano. Ash masks should be worn in ashy conditions or
when you disturb ash. The Belham valley should be avoided during and after
periods of heavy rain and everyone is reminded that access to Plymouth,
Bramble airport and beyond is prohibited. There is a maritime exclusion zone
around the southern part of the island that extends two miles beyond the
coastline from Trant's Bay in the east to Garibaldi Hill on the west coast.
The daytime entry zone remains closed.
12 noon, Friday, 10 November 2000
Topic 2 of 99 [Geo]: Vulcanism
Response 310 of 997: Marcia (MarciaH) * Sun, Nov 19, 2000 (14:14) * 61 lines
**************************************
KVERT Update, Friday, Nov. 10, 2000
**************************************
From: Alaska Volcano Observatory
Kamchatkan Volcanic Activity
INFORMATION RELEASE 00-50
Friday, November 10, 2000, 11:30 KST (2330 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Standard Time, 21 hours ahead of Anchorage.
KLYUCHEVSKAYA GROUP OF VOLCANOES
KLYUCHEVSKOY VOLCANO 56o03'N, 160o39'E;
Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
During the past week (November 3-9), seismic activity was near background
levels. On Nov. 3, weak fumarolic activity was observed. On Nov. 4,6, and
7, a gas-steam plume rose 150-800 m above the volcano and extended 10 km to
the southeast on Nov. 7. On other days, clouds obscured the volcano.
BEZYMIANNY VOLCANO 55o58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS YELLOW.
Seismicity has decreased to background levels. No Nov. 3-6, a gas-steam
plume rose 1000-2000 m above the volcano and extended 20-60 km mainly to
the southeast. On Nov. 7, a gas-steam plume rose 500 m above the volcano.
On Nov. 9, clouds obscured the volcano.
SHEVELUCH VOLCANO 56o38'N, 161o19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
On Nov. 3-4, 6, and 8, a gas-steam plume rose 100-300 m above the dome. On
Nov. 7, a gas-steam plume rose 1500 m above the dome. On other days,
clouds obscured the volcano.
KARYMSKY VOLCANO 54o03'N, 159o27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKAYA GROUP OF VOLCANOES, 53o15'N, 158o51'E;
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes is at normal levels.
MUTNOVSKAYA GROUP OF VOLCANOES:
GORELY VOLCANO, 52o33'N, 158o02'E, Elevation 1,828M
MUTNOVSKY VOLCANO, 52o27'N,158o12'E, Elev. 2,324 M.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On Nov. 3-8, Gorely volcano wa quiet, and a gas-steam plume rose 300-800 m
above Mutnovsky volcano. On Nov. 9, the volcanoes were obscured by clouds.
The seismicity was near background levels.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS.
Olga Chubarova Tom Miller
Kamchatka Volcanic Eruptions Alaska Volcano Observatory
Response Team, IVGG, Piip Blvd, 9 4200 University Drive
Petropavlovsk-Kamchatsky, 683006, RUSSIA Anchorage, Alaska 99508
E-mail: ochubarova@emsd.iks.ru E-mail: tmiller@usgs.gov
tel. (415-22)59385 907-786-7454
Topic 2 of 99 [Geo]: Vulcanism
Response 311 of 997: Marcia (MarciaH) * Mon, Nov 20, 2000 (21:24) * 34 lines
********************************
Caribbean Volcano Cruise II
********************************
From: David Lea
Announcement:
Many of you may have heard about the volcano cruise that took place in the
Caribbean last year aboard the 150 foot topsail schooner, Sir Robert Baden
Powell. Well we are having another one in 2001, only instead of 21 days, it
will only be 10 days long. You can check out the ship that we will be
sailing on and get a lot more information by going to last years website
at: www.volcano-island.com/cruise
The ship will depart Martinique in the French West Indies on April 3, 2001
The passengers/participants will disembark in St. Maarten on April 14, 2001
The volcanic islands we will be visiting will be Martinique, Dominica,
Guadeloupe, Montserrat, Nevis and St.Kitts
The leader of this expedition will once again be David Lea, well known
videographer of the Montserrat eruption and creator of the documentary
series, "The Price of Paradise" and other educational videos.
www.priceofparadise.com
We will be climbing the volcanoes in Martinique, Guadeloupe, Nevis and St.
Kitts, along with a visit to the famous boiling lake in Dominica.
Montserrat will no doubt be the centerpiece of the cruise as it is still in
eruption. Visits to all of the observatories are also being arranged. The
ship is also fully equipped with the latest diving gear for those of you
that are interested in some great diving.
For further information you can contact David Lea directly at:
lead@candw.ag
Topic 2 of 99 [Geo]: Vulcanism
Response 312 of 997: Marcia (MarciaH) * Tue, Nov 21, 2000 (20:10) * 6 lines
Who wold be stupid enough to live on a live volcano?!
Cities on Volcanoes 2 conference (12-16 February 2001, Auckland, New Zealand)
programme now available on-line at:
http://www.gns.cri.nz/news/conferences
Topic 2 of 99 [Geo]: Vulcanism
Response 313 of 997: Marcia (MarciaH) * Tue, Nov 21, 2000 (20:11) * 44 lines
****************************************
Piton de la Fournaise, Reunion activity
****************************************
Piton de la Fournaise eruption which started on october 12, suddenly stopped
on november 13, after 33 days of continuous eruption.
During the last five days of activity, tremor was unusually high and at
Piton Morgabim very vigorous eruption activity occured.
On november 9th, a new eruption went opened some 30 m above the initial one
and slight phreatomagmatic events could be observed.
On november 13 at 22h45 (local time) the tremor suddenly disappeared within
only 15 minutes.
On november 15, up to 800 °C hot lava fields were still present formed by
the final lava flows.
The crater showed an about 100 m large and an about 40 m deep cavity, which
was formed by welding together of both eruption sites.
Thomas Staudacher & Jean Louis Cheminée
Observatoire Volcanologique du Piton de la Fournaise
Institut de Physique du Globe de Paris
14 RN3, le 27ème
97418 La Plaine des Cafres
La Réunion
tél.: 02 62 27 52 92
fax.: 02 62 59 12 04
***************************************
White Island and Ruapehu, New Zealand
***************************************
For week ending 17 November, White Island developed a new degassing vent
just SE of MH vent and MH vent was noisely actively degassing too. No
significant change in seismicity at White Island though. Minor volcanic
tremor continues at Ruapehu.
From: http://www.gns.cri.nz/hazardwatch/latest/gweekvo.htm
White Island continues to emit steam and gases. Early in the week the noise
from the active MH vent was so loud that it could be heard from the beach
in still conditions. By Thursday, a small new vent southeast of MH was also
steaming. This slight increase in activity was not accompanied by any
significant seismic activity. At Ruapehu minor levels of volcanic tremor
continue to be recorded.
Topic 2 of 99 [Geo]: Vulcanism
Response 314 of 997: Marcia (MarciaH) * Sun, Nov 26, 2000 (22:37) * 18 lines
*******************************************
Vanuatu volcanoes on "STROMBOLI ON-LINE"
*******************************************
From: Roberto Carniel
Dear volcanophiles
Just a brief note to let you know that STROMBOLI ON-LINE
(http://stromboli.net)
has established, after field work done by Carniel and Fulle in July 2000 on
Ambrym, Lopevi and Yasur, a section on Vanuatu's volcanoes.
It includes photos, videoclips, maps and a QuickTime-VR panorama of Yasur.
The direct URL is:
http://stromboli.net/perm/van/index-en.html
As always, this material is also available in German and Italian:
http://stromboli.net/perm/van/index-de.html
http://stromboli.net/perm/van/index-it.html
Topic 2 of 99 [Geo]: Vulcanism
Response 315 of 997: Marcia (MarciaH) * Mon, Nov 27, 2000 (20:42) * 38 lines
*********************************
Api Siau and Merapi, Indonesia
*********************************
For the week ending 20 November, Api Siau (Karangetang) ejected ash from
its two active craters, frequent boomings and nighttime glares. Merapi
emitted a thin ash plume to 530m and notable seismicity continued.
From: http://www.vsi.dpe.go.id/news/index.html
Weekly Report No. 590
14-20 November 2000
Karangetang
Siau island; 2°47' N, 125°29' E
Karangetang activity continued during this week. White-thin ash plume
appeared from main crater and crater II rose up 600 m height above the
summit. A frequently booming sound was heard from the summit. Sometimes at
night sight the observer noted red flame from the summit, the height is
about 75 m.
Seismic record dominated by discontinuous tremor, which has amplitude 0.5-4
mm. During this week seismograph also recorded some multiphase earthquakes.
Detail of seismic activity were: deep volcanic (A) 7 events, 3 events of
shallow volcanic (B), 51 events of multiphase, 18 events of small
explosion, 45 events of tectonic, and discontinuous tremor earthquake.
Karangetang volcano is in level 2.
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Merapi volcano continued to ejecting white ash plume. During the week ash
plume rose up 530 m height above the summit and low in pressure.
Seismograph recorded both of deep and shallow volcanic earthquakes, but
seismicity still dominated by multiphase earthquakes.
Merapi volcano is in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 316 of 997: Marcia (MarciaH) * Mon, Nov 27, 2000 (20:53) * 58 lines
*************************************
MVO weekly report, 24 November 2000
*************************************
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 17 November 2000 to midday, 24 November 2000
Activity at the Soufrière Hills volcano has remained at an elevated level
this week with the continued growth of the lava dome and a marked increase
in the number of rockfall signals.
The level of seismic activity was higher than in the previous week. The
broadband seismic network recorded a total of 497 rockfall signals, 1
volcano-tectonic, 85 long period and 16 hybrid earthquakes for the reporting
period. The number of rockfalls has more than doubled relative to the
previous week, although the number and energy of the long period earthquakes
has decreased.
Clear views of the dome were seen over the period from 17 to 22 November.
The lava spine that had been extruding over the previous week was seen
briefly on 17 November and the height of the top of the spine was estimated
as over 1085 m or 3560 feet. However views over the weekend showed that the
large spine had collapsed and a number of smaller spines were visible in the
summit area.
On the afternoon of 17 November and over the following few days, rockfalls
and small pyroclastic flows were occurring down the notch between the
northeastern and northern lobes of the 1995-98 dome. These were reaching
into the upper parts of Tuitt’s and White’s ghauts to the northeast of the
dome and traveling down the northern edge of the Tar River valley. Some new
deposits were also noted in the upper White River valley to the south of the
dome. Ash clouds from this activity reached no more than 10,000 feet and
mostly traveled to the west across the exclusion zone. Towards the end of
the week, the rockfall activity down the eastern flank had decreased,
although the number of rockfalls detected by the seismic network remained
high.
Measurements of sulphur dioxide emissions from the volcano were made on 23
November and showed that the average flux was 1050 tonnes per day. This is
higher than the previous measurement of 610 tonnes per day on 10 November,
but is similar to other measurements made over the last 3 months.
Residents of Montserrat and visitors to the island are advised to tune in to
ZJB Radio for up-to-date information on the status of the volcano. Rockfall
and pyroclastic flow activity is likely to remain at a high level whilst the
dome continues to grow, producing ash clouds which may blow over inhabited
areas if winds are from the south or southeast. Elevated levels of
pyroclastic flow activity may develop very rapidly and could affect any
valleys around the volcano. Ash masks should be worn in ashy conditions or
when you disturb ash. The Belham valley should be avoided during and after
periods of heavy rain and everyone is reminded that access to Plymouth,
Bramble airport and beyond is prohibited. There is a maritime exclusion zone
around the southern part of the island that extends two miles beyond the
coastline from Trant’s Bay in the east to Garibaldi Hill on the west coast.
The daytime entry zone remains closed.
12 noon, Friday, 24 November 2000
Topic 2 of 99 [Geo]: Vulcanism
Response 317 of 997: Marcia (MarciaH) * Mon, Dec 4, 2000 (22:18) * 50 lines
*************************************
MVO weekly report, 1 December 2000
*************************************
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 24 November 2000 to midday, 1 December 2000
Activity at the Soufrière Hills volcano has remained at an elevated level
this week with continued growth of the lava dome.
The level of seismic activity was comparable to last week. The broadband
seismic network recorded a total of 491 rockfall signals, no
volcano-tectonic, 69 long period and 13 hybrid earthquakes for the reporting
period.
Clear views of the dome were possible briefly on the evening of 27 November.
The crest of the dome was dominated by a large shark’s fin-shaped spine.
Glowing rockfalls were seen cascading down the eastern and southeastern
faces of the dome. Poor visibility through the rest of the week prevented
further observations being made, although new rockfall deposits were seen
predominantly in the upper reaches of the Tar River valley.
Measurements of sulphur dioxide emissions from the volcano were made on 28
November and showed that the average flux was 1020 tonnes per day. This is
similar to the values measured last week.
Dr. Glenn Mattioli, Andy Eby and Lizzette Rodriguez from the University of
Puerto Rico are visiting Montserrat this week to collaborate with the MVO in
a GPS monitoring campaign. Occupations of several sites around the volcano
are in progress, using both MVO and University of Puerto Rico equipment, so
that the movements of the flanks of the volcano can be measured very
accurately. This is part of a long-established collaborative venture that
has been ongoing since the start of the eruption.
Residents of Montserrat and visitors to the island are advised to tune in to
ZJB Radio for up-to-date information on the status of the volcano. Rockfall
and pyroclastic flow activity is likely to remain at a high level whilst the
dome continues to grow, producing ash clouds which may blow over inhabited
areas if winds are from the south or southeast. Elevated levels of
pyroclastic flow activity may develop very rapidly and could affect any
valleys around the volcano. Ash masks should be worn in ashy conditions or
when you disturb ash. The Belham valley should be avoided during and after
periods of heavy rain and everyone is reminded that access to Plymouth,
Bramble airport and beyond is prohibited. There is a maritime exclusion zone
around the southern part of the island that extends two miles beyond the
coastline from Trant’s Bay in the east to Garibaldi Hill on the west coast.
The daytime entry zone remains closed.
12 noon, Friday, 1 December 2000
Topic 2 of 99 [Geo]: Vulcanism
Response 318 of 997: Marcia (MarciaH) * Thu, Dec 14, 2000 (19:48) * 49 lines
**********************************************************
Updates: Semeru, Api Siau and Bromo Volcanoes, Indonesia
**********************************************************
For the week of 5-11 December 2000, Semeru's eruption, which began 33 years
ago, continues with thick white fume, two pyroclastic flows and numerous
explosions (513 explosion earthquakes). Api Siau (a.k.a. Karangetang)
exhibited fume columns from both active craters and occasional nighttime
glares to 25m height and a marked increase in seismicity (which includes
continous tremor). The new eruption at Bromo with manifold explosions and
ash columns rising to as much as 900m a.c. (above crater), continuous
tremor and strong sulfur odor.
Source report: http://www.vsi.dpe.go.id/news/index.html
Weekly Report No. 593
5-11 December 2000
Semeru
East Java; 8°6.50' S, 112°55' E
A 600 m white-thick fume rose from Jonggring Seloko crater. Seismic record
dominated by explosion earthquake (513 events), the others record were: 1
event of deep volcanic (A), 1 event of shallow volcanic (B), 16 events of
avalanche, 6 events of tectonic, and 2 event of pyroclastic flow.
The alert level of Semeru volcano is in level 2.
Karangetang
Siau island; 2°47' N, 125°29' E
Volcanic activity increased during reported period, white-thin fume
exhibited from crater II and main crater. This fume reached 50 m above the
summit. An indistinct fire plume observed frequently at night sight. The
fire plume reached up to 25 m above the summit. An extrem increase on
volcanic earthquake occurred within this week. Seismic record showed: 135
events of deep volcanic (A) earthquake, 1 event of shallow volcanic (B),
151 events of multiphase, 74 events of small explosion, 8 events of
tectonic, and a continuous of tremor volcanic.
Karangetang volcano is in level 2.
Bromo
East Java; 7°56.30' S, 112°37' E
Within this period, G. Bromo still stated as "waspada" level. Volcanic
activity marked by ongoing explosion and continuous tremor. Ash explosion,
which is accompanied by grey-brown to dark fume. Fume's height
approximately 150-900 m above crater rim, sulphur smelled strongly from
observation post. 817 events of explosion earthquake, which has amplitude
of 4-30 mm and continuous tremor, which has amplitude of 2-6 mm recorded
during observation period.
Bromo volcano is in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 319 of 997: Marcia (MarciaH) * Thu, Dec 14, 2000 (21:40) * 24 lines
***************************************
Colima, Fuego, and Tungurahua updates
***************************************
Colima, Mexico
---------------
As of 1800 on 6 December, activity at Colima was at low seismic,
deformation and visual levels. The recent tendency has been that of low,
waning levels of measured activity. See:
http://www.ucol.mx/volcan/report1.html
Fuego, Guatemala
-----------------
Several small explosions at Guatemala's Fuego volcano in the evening of 9
December.
Tungurahua, Ecuador
---------------------
Thin ash plume from Ecuador's Tungurahua volcano in the early hours of 10
December.
Source: http://www.ssd.noaa.gov/VAAC/messages.html
Topic 2 of 99 [Geo]: Vulcanism
Response 320 of 997: Marcia (MarciaH) * Tue, Dec 19, 2000 (18:14) * 3 lines
Popocatepetl is erupting - for updating image please go to:
http://www.cenapred.unam.mx/images/popo.jpg
Topic 2 of 99 [Geo]: Vulcanism
Response 321 of 997: Marcia (MarciaH) * Tue, Dec 19, 2000 (19:01) * 1 lines
or try http://www.cenapred.unam.mx/popo/UltimaImagenVolcan2.html
Topic 2 of 99 [Geo]: Vulcanism
Response 322 of 997: Marcia (MarciaH) * Tue, Dec 19, 2000 (21:17) * 14 lines
Popocatepetl volcano, seen from the Mexican village of San
Nicolas de los Ranchos, erupts late December 18, 2000. The
eruptions have caused small forest fires on its slopes in Puebla
state where thousands of residents had been evacuated, but many
others refused to leave. (Daniel Aguilar/Reuters)
--------------
Ash Plume earlier in the week - Popocatepetl, Mexico
Topic 2 of 99 [Geo]: Vulcanism
Response 323 of 997: Marcia (MarciaH) * Tue, Dec 19, 2000 (21:25) * 76 lines
Mexico's Popocatepetl Erupts, Thousands Evacuated
SAN PEDRO CHOLULA, Mexico (Reuters) - Mexico's
Popocatepetl volcano spewed molten rock into the sky Tuesday
forcing more than 30,000 people to abandon their homes and
sparking fears a glacier could become dislodged and trigger
massive mudslides.
Flaming rock burst from the 17,884-foot high volcano at 2 a.m. on
-- the second eruption in a few hours in what was the volcano's
most violent activity for decades -- perhaps centuries.
Mexican authorities, fearing a roughly 3,000 feet long glacier on
the volcano's western face could become dislodged by molten
rock and cause mudslides, expanded an emergency zone to 12.5
miles from 7.5 miles.
"We are on maximum alert ... because we have to be ready for
any possible contingency regarding the glacier," Interior Minister
Santiago Creel told a news conference on Tuesday.
The volcano, revered as a divinity by indigenous peoples before
the 1521 Spanish Conquest, was stable later Tuesday but
authorities predicted more activity before the day was out.
Authorities helped establish makeshift shelters for the more than
30,000 evacuees, whose homes were near the base of the
volcano.
Creel said eventually more than 48,000 people living in central
Puebla, Mexico and Morelos states near the mountain -- Mexico's
second highest -- would have to be evacuated from their homes.
President Vicente Fox flew by helicopter to towns near the volcano
and toured evacuee shelters as government officials met to
coordinate their response to the emergency.
EVACUATED VILLAGERS FEAR FOR HOMES, FAMILY
MEMBERS
In a refuge in San Pedro Cholula, in Puebla state which Fox visited
early Tuesday, villagers who had been evacuated from their
homes voiced worries about family members who had been
separated from them in the upheaval.
"I want to find my children. They are very small. They left the
house first and by the time I came out last night they had gone, I
must look for them," Margarita Cortes, carrying a baby on her
back, told Reuters.
Cortes' husband, like other men from villages at risk, stayed back
out of fear for his home. Others have been driven home in army
trucks to check on their abandoned properties.
One man, aged 75, apparently overcome by shock from the
eruption, reportedly died of a heart attack on Monday in the village
of San Pedro Benito Juarez, in Puebla state.
Local radio reported that in the village of Santiago Xalitzintla, in
Puebla state, soldiers forced residents to leave their houses on
Monday night as the mountain threw up slabs of molten rock,
some as much as 1.5 feet (45 cm) in diameter.
Army patrols were manning many of the roads into communities
closest to the volcano. Puebla city airport was closed on Tuesday.
Popocatepetl, or "smoking mountain" in the indigenous Nahuatl
language and pronounced poh-poh-kah-teh-peh-til, was inactive
from 1927 to 1994, when there was a moderate eruption. Since
then it has been increasingly active, sending up smoke and ash
columns.
In April 1996, five mountain climbers died near the crater's rim
during an explosion of the volcano, which is believed to have been
formed about 300,000 years ago.
Fox, who was sworn in on Dec. 1, attempted to reassure villagers
in refuges as government officials met to coordinate their
response to the emergency.
"You can rest assured, the army is looking after your houses and
everything," he told a woman in an evacuation shelter in Chalco, in
Mexico state.
Creel said some 1,500 troops from the armed forces and 800
more police were involved in the emergency operation and that
there had only been minor incidents of looting.
Airplanes were taking off and landing normally in Mexico City
airport, 42 miles from the volcano. Ash can pose a danger to
airplanes if it enters their turbines.
"...No airline has suspended flights," Roberto Canovas, director of
the air terminal, told journalists.
Mexico City authorities said a rain of ash could cover the city but
so far winds had blown the volcanic ash toward Puebla state.
Topic 2 of 99 [Geo]: Vulcanism
Response 324 of 997: Marcia (MarciaH) * Thu, Dec 21, 2000 (00:07) * 24 lines
***********************
Popocatepetl, Mexico
***********************
As many of you are aware, Popocatepetl in Mexico erupted large amounts of
ash and steam last week, and experienced a spectacular eruption on Monday
night (December 18). Some reports say it was the largest eruption in over
a thousand years. Since Monday night, it has erupted at least three times,
in its greatest activity in over 400 years. Activity seems to have slowed
today, Wednesday December 20.
Updates on Popocatepetl activity can be found at the CENAPRED web site:
http://www.cenapred.unam.mx/
Reports are also available through the Smithsonian Global Volcanism Program
Preliminary Notices of Volcanic Activity,
http://www.volcano.si.edu/gvp/gvn/world/index.htm
and at the Volcano World website,
http://volcano.und.nodak.edu/vwdocs/current_volcs/popo/mar5popo.html
Finally, general news coverage can be found at:
http://dailynews.yahoo.com/fc/Science/Earthquakes_and_Seismology/
Topic 2 of 99 [Geo]: Vulcanism
Response 325 of 997: Marcia (MarciaH) * Fri, Dec 22, 2000 (20:07) * 29 lines
*********************************
Bromo Volcano, Indonesia
*********************************
Bromo volcano in Indonesia began a new eruption on 30 November. Prior to
that there was no specific precursory events known, although the monitoring
seismograph has been down since 18 October, just the usual white gas plume
of low intensity, rising ~50m. Some sort of increased activity may have
begun earlier since the local government urged a no-climbing effort on the
29th. The initial explosion sent up a dark ash cloud to 100-150m ht.
Increased activity thereafter with ash clouds to 600-700m a.c. (above
crater). Ash falls to 1-3cm depth at distances of 40 km by early December.
From: http://www.vsi.dpe.go.id/news/index.html
Bromo Crisis
4 December, 2000
A minor explosion occurred suddenly on Bromo volcano on 30 November 2000.
There was no a specific cursor before it. Daily activity marked by white
ash plume which had low intensity and rose up about 50 m height. There is
no seimicity data because the seismograph did not work since 18 October 2000.
The first explosion ejected dark ash as height as 100-150 m height above
the crater rim. An explosion ongoing up to now and increased. Ash explosion
reached 600-700 m height above the crater rim and hit 1-3 cm thick in 40 km
distance from the volcano.
Since 29 November 2000 a local government recommended to people living
around volcano and tourists not to climb the volcano for a several time
until normal. Bromo activity increased and stated in level 2.
For further monitoring VSI will be repair the old seismograph and install
the new telemetry one and EDM (Electronic Distance Measurement).
Topic 2 of 99 [Geo]: Vulcanism
Response 326 of 997: Marcia (MarciaH) * Fri, Dec 22, 2000 (20:07) * 31 lines
*********************************
Popocatepetl, Mexico (1401-09)
*********************************
Tue, 12 Dec 2000
There was a massive exhalation of ash and steam from the volcano
Popocatepetl, near Mexico City. The eruption was detected by the Center for
Prevention of Natural Disasters (CENAPRED), and relayed to the Washington
D.C. Volcanic Ash Advisory Center (VAAC) by way of the Mexico City
Meteorological Watch Office.
The eruption began at approximately 2207 UTC (5:07 EST) and was immediately
visible on the Popocatepetl "Web Cam" set up by CENAPRED. A large plume of
mostly ash (judging by the darkened color of the plume) was seen exiting
the summit. An analysis of subsequent imagery from the National Oceanic and
Atmospheric Administration (NOAA) Geostationary Operational Environmental
Satellite (GOES-8) indicated a dense ash cloud extending 37 kilometers (20
nautical miles) to the northeast. The immediate area around the volcano was
clear of water clouds at the time. The only disability in the satellite
detection was a post GOES-8 maneuver that resulted in a navigation error of
about 30 to 50 kilometers.
The ash cloud was estimated to reach a level of 29,000 feet above sea level
based on upper air wind observations.
For details of the current eruption including real time satellite imagery,
visit:
http://www.ssd.noaa.gov/VAAC/popo.html
Topic 2 of 99 [Geo]: Vulcanism
Response 327 of 997: Marcia (MarciaH) * Fri, Dec 22, 2000 (20:09) * 62 lines
*****************************
Volcano Expedition website
*****************************
From: David Hilton (David Hilton)
Please join us on a scientific expedition to study the volcanoes of Costa
Rica via the Internet beginning Thursday, January 4, 2001.
The Scripps Web site, titled Volcano Expedition
(http://www.sio.ucsd.edu/volcano/), will allow users to log on and follow a
two-week-long field trip to six active volcanic areas in the highlands of
Costa Rica in Central America. The site will feature photographic
documentation of the expedition, along with videos of the field research
being conducted by a multinational team of earth scientists and graduate
students. Web users will be able to travel along with the team by logging
on to daily reports from the field.
This expedition represents the first stage of an NSF-sponsored
investigation of the volatile systematics of the Central America volcanic
margin. We will target recent lavas, fumaroles, and geothermal waters. The
goal is to understand geochemical cycling through the earth's crust via the
processes of subduction and volcanic emission.
David Hilton (Scripps Institution of Oceanography)
*****************************
Lake Nyos, Cameroon website
*****************************
From: Gaudru
Dear Colleague,
We are pleased to inform you that a new website concerning the Lake Nyos in
Cameroon is now running.
In 1986, a tremendous explosion of CO2 from the lake Nyos, West of
Cameroon, killed more than 1700 people and livestock up to 25 km away. The
dissolved CO2 is seeping from springs beneath the lake and is trapped in
deep water by the high hydrostatic pressure. If the CO2 saturation level is
reached, bubbles appear and draw a rich gas water up. An avalanche process
is triggered which results in an explosive over-turn of the whole lake. A
French team has carried out since 1990 a series of tests in an attempt to
release the gas slowly through vertical pipes. The site, also, show a
general overview about the Lake and the degassing project. Information
contact for the site : Michel.Halbwachs@univ-savoie.fr
To access directly at the Nyos homepage :
http://perso.wanadoo.fr/mhalb/nyos
and/or by a direct link from the SVE website : http://www.sveurop.org (see
article/Lake Nyos)
(in addition, we inform you that a new page about the recent SVE mission on
the Serreta submarine volcano (Azores) is also already running) - under
construction
Topic 2 of 99 [Geo]: Vulcanism
Response 328 of 997: Marcia (MarciaH) * Tue, Dec 26, 2000 (17:03) * 9 lines
*********
Kilauea
*********
0550 December 26, 2000
Boxing Day at Kilauea brings more lava on Pulama pali. This morning at 0459, a moderately vigorous flow has reached the base of the pali 200-400 m farther west than the flows of the past week. The new flow apparently is fed from either a higher breakout point than were the previous flows or a tongue of these flows that headed more southward than normal. The new flow is burning scattered trees, but kona winds blow the smoke smell northward, leaving clean air on the coastal flat.
The previous flows are still visible farther east on the pali, but they are mostly crusted over, with four large incandescent patches separated by dull crust.
Mapping on Sunday, and glow this morning, indicate that lava is slowly moving seaward on the coastal flat. Still, more than 2 km separate the flow front from the water.
The crater of Pu`u `O`o is dark this morning, seismic tremor near Pu`u `O`o is weak to moderate and beneath Kilauea caldera is weak, and the tilt at Kilauea summit and along the east rift zone is flat.
Topic 2 of 99 [Geo]: Vulcanism
Response 329 of 997: (sprin5) * Wed, Dec 27, 2000 (04:07) * 1 lines
What is the significance of boxing day in Hawaii, I know they have this in Candada as well.
Topic 2 of 99 [Geo]: Vulcanism
Response 330 of 997: Marcia (MarciaH) * Mon, Jan 1, 2001 (15:44) * 1 lines
Nothing whatsoever. We are totally Americanized here. I guess we were not colonized out here for long enough and the New England missionaries brought American traditions with them. No Boxing day except to return the boxes you got the day before you did not like...
Topic 2 of 99 [Geo]: Vulcanism
Response 331 of 997: Marcia (MarciaH) * Fri, Jan 5, 2001 (00:26) * 19 lines
Proof of Kilauea’s big bang shocks Hawaii geologists
The volcano once had a
Mt. St. Helens-style eruption,
never before known in the islands
By Rod Thompson
Big Island correspondent
HILO -- Sometime before 1000 A.D., Kilauea volcano blasted skyward in an eruption so massive it sent rocks and dust as much
as 18 miles into the air.
The cloud of debris may have been seen on Maui, said Don Swanson, scientist-in-charge at the Hawaiian Volcano Observatory.
And the eruption may have changed the way Hawaiians viewed Kilauea, ushering in the new volcano goddess Pele, said Hawaiian
cultural consultant Kepa Maly.
For several years, geologists have known about fist-size rocks shot through the air, different from surrounding rocks, lying on the
ground south of Kilauea, Swanson said.
In August, geologists took a closer look.
"What we found surprised, even shocked us," Swanson said. About five miles from the summit, they found a rock weighing 4.3
pounds. At six miles from the summit, they found one weighing nearly 3 pounds.
Topic 2 of 99 [Geo]: Vulcanism
Response 332 of 997: Marcia (MarciaH) * Fri, Jan 5, 2001 (00:27) * 2 lines
more of the above article plus maps:
http://starbulletin.com/2001/01/04/news/story2.html
Topic 2 of 99 [Geo]: Vulcanism
Response 333 of 997: Marcia (MarciaH) * Fri, Jan 5, 2001 (15:53) * 5 lines
check http://www.spring.net/yapp-bin/restricted/read/geo/2.161
then look at this aerial view of where he was camped - in center foreground on an old hilltop!
http://hvo.wr.usgs.gov/hazards/dds24167_L.jpg
Topic 2 of 99 [Geo]: Vulcanism
Response 334 of 997: Cheryl (CherylB) * Tue, Jan 9, 2001 (17:58) * 1 lines
How far away is Maui from Hawaii?
Topic 2 of 99 [Geo]: Vulcanism
Response 335 of 997: Marcia (MarciaH) * Wed, Jan 10, 2001 (14:22) * 16 lines
The Alahelenui channel is about 12 miles across - one of the roughest channels in the world. It separates The Kohala mountains of Hawaii from Haleakala Volcano on Maui.
Re Popocatepetl: From Yahoo Volcanology Club's Steve:
Some phreatic emmissions are visable.
Sulfur dioxide emmisions were reported to be slightly lower.
I am unsure how reliable Mex television is.
Volcanologist here recommended against any people being allowed back
into area closer than Oaca and &or 10 km of the volcano.
Ary troops are still in the area for any further actions to remove
people.
Some residents have drifted back dispite concerns of
so 2 and other vapors .
Biggest fear is the melting of the glacial snow as clodest par of year
is passing fast.
Topic 2 of 99 [Geo]: Vulcanism
Response 336 of 997: Marcia (MarciaH) * Thu, Jan 11, 2001 (20:47) * 36 lines
A field trip and conference in the week immediately preceding the Cities on
Volcanoes 2 conference in Auckland, New Zealand.
A conference and field trip to be held in Australia in early February 2001
will be concerned with scoria cones and small lava shields of Quaternary
age, extensive flows, and some 40 maar volcanoes with tuff rings, crater
lakes and swamps, which occur on the Western Victorian Volcanic Plains.
A field trip leaves Melbourne on Saturday 3rd February 2001 and travels
through the main volcanic field with leaders who have worked on
volcanicity, dating, crater lake stratigraphy and fauna sequences, pollen
sequences and recent lake level change related to current climate
fluctuation. Staying for two nights in the old pastoral town of Camperdown,
and then reaching the small historic coastal town of Port Fairy in far
Western Victoria on the afternoon of Monday 5th, about 50 researchers and
post-graduate students will meet for the rest of the week to discuss all
aspects of the Quaternary history of the region, as part of a regular
meeting of the Australasian Quaternary Association (AQUA). A mid-conference
field trip on Wednesday 7th will visit the famous Tower Hill nested maar,
and also the nearby Mt Eccles volcanic complex and young stony rise flows.
The conference will conclude at lunchtime on Friday 9th February, allowing
attendees to return to Melbourne in time to catch evening flights at
Melbourne airport, and so allowing ample time to travel to Auckland for the
Cities on Volcanoes 2 meeting commencing on Monday 12th.
The young volcanic subprovince of Western Victoria has many similarities to
the Auckland field and this meeting provides an interesting (and
inexpensive!) opportunity for those going to the Auckland meeting, or just
interested in young areal volcanism, to see another famous field, and hear
the latest information on dating, volcanic history and the risk of future
eruption.
For details of the conference, field trip and other program details see:
http://www.arts.monash.edu.au/ges/research/conference.html
Topic 2 of 99 [Geo]: Vulcanism
Response 337 of 997: Marcia (MarciaH) * Thu, Jan 11, 2001 (21:33) * 45 lines
******************************
Mayon Volcano, Philippines
******************************
From: Dan Shackelford
Subject: Something brewing at Mayon
Activity at the beautifully conic Philippine volcano Mayon seems to be
increasing. Increased seismicity, a growing summit lava dome and copious
amounts of gas have been noted. Inflation has been noted, indicating
possible magma ascending in the conduit. No crater glows though, yet.
From: http://www.phivolcs.dost.gov.ph/Volcanoes/Mayon/MayonIndex.html
(follow link at top of page to latest bulletin and photos)
Mayon Volcano Bulletin
7:00 PM, 09 January 2001
A possible resurgence of activity is evident from recent observations on
Mayon. Reports by the Ligñon Hill Observatory in Legazpi City disclosed an
apparently growing lava dome, which is also emitting voluminous volcanic
gases from the summit crater. Significantly increased earthquake
occurrences have also occurred this past week and these events are likely
related to ascent of magma. Such ascent is also indicated by slight ground
tilt that has coincided with appearance of the lava dome, and the sustained
gas outputs visible during cloud breaks. Due to near-constant cloud cover,
however, no crater glow has been observed yet but the major monitored
parameters strongly suggest that activity is rapidly progressing beyond the
usual background or quiet conditions.
Because of the reactivation of the volcano which may eventually lead to a
lava flow-producing or pyroclastic flow-producing eruption, PHIVOLCS is now
hoisting Alert Level 2, meaning increased and sustained volcanic unrest. No
time frame or precise eruption prediction can be given yet because of the
short observation period and the lack of good visibility of the summit
area. As a precaution against hazards from sudden explosions, however,
PHIVOLCS advises the public to stay away from the six (6) kilometer radius
Permanent Danger Zone (PDZ) and to avoid major river channels that
originate from the volcano. In addition, all treks within the prescribed
PDZ, should be postponed until the alert has been lowered to the
appropriate level.
In the meantime, additional volcano monitoring teams are now being sent
on-site to further evaluate the unrest and any significant developments
shall be relayed to all concerned.
PHIVOLCS
Topic 2 of 99 [Geo]: Vulcanism
Response 338 of 997: Marcia (MarciaH) * Sat, Jan 13, 2001 (22:07) * 23 lines
U.S. Relief Supplies to Be Sent to El Salvador
WASHINGTON (Reuters) - A U.S. aid agency said on Saturday it would
dispatch a planeload of plastic sheeting, medical kits, blankets and
other supplies to earthquake victims in El Salvador as soon as an
airport there reopened.
"We have supplies prepared and ready to go in Miami but we have to
wait until an airport is open for us to land in," said Joseph Schultz, a
spokesman for the U.S. Agency for International Development.
The supplies will include plastic sheeting to create makeshift shelter,
five-gallon plastic jugs for water, personal hygiene kits, medical kits
and blankets, he said.
The agency said it had three people on the ground in El Salvador, and
hoped to get five more emergency workers into the Central American
nation by early on Sunday.
The spokesman said he had no information regarding the powerful
earthquake because of downed telephone lines.
The quake's epicenter was about 65 miles southeast of the capital San
Salvador. Red Cross and local authorities said dozens of people had
died in El Salvador and Guatemala.
A spokesman for the Pentagon said there were no immediate plans to
send U.S. military troops to the area to assist with emergency relief.
Topic 2 of 99 [Geo]: Vulcanism
Response 339 of 997: Marcia (MarciaH) * Sat, Jan 13, 2001 (22:09) * 74 lines
Central America Quake Death Toll Up
SAN SALVADOR, El Salvador (AP) - A major earthquake shook Central
America on Saturday, unleashing a landslide that buried hundreds of
houses near El Salvador's capital and killing at least 63 people across
the region.
About 1,200 people are believed to be missing in the buried Las
Colinas neighborhood just west of San Salvador, Red Cross spokesman
Carlos Lopez Medina said.
Medina said that at least 61 people were killed across El Salvador but
the national police estimated the death toll at near 100.
The 7.6-magnitude quake centered off El Salvador's southern coast
also rocked Honduras and Guatemala, where two deaths were reported.
Buildings swayed in Mexico City, about 600 miles to the northwest.
Salvadoran President Francisco Flores declared a national emergency
and appealed for international aid to help look for buried victims and
assist survivors.
Hundreds of rescuers frantically ripped at the earth with sticks and bare
hands to reach those buried in the middle class Las Colinas area,
where a 1,500-foot landslide carried away houses, cars and trees.
A distraught Arturo Magana, 25, wandered about to find his 18-year-old
brother, Jaime.
``I don't know where to dig because I don't know where the house is,''
he said.
``This is terrible. I don't think we will be able to pull out any victims;
everything has been buried,'' said David Lara, a rescue worker
struggling at the mass of dirt and concrete with a shovel.
Lopez estimated that 300 houses had been destroyed in Las Colinas.
By night, 20 bodies had been recovered at Las Colinas. No survivors
had yet been found.
``There is my boy! Help me! Help me!'' wailed Carmen de Marin, a
41-year-old woman weeping beside the buried ruins of her Las Colinas
house.
She said her 12-year-old son Jaime Ernesto Marin had stayed home to
await a phone call from his father in the United States when she went
out shopping shortly before the quake hit at about 11:35 a.m.
In the southeastern town of San Miguel, the wall of a hospital collapsed
and 25 people were known to be dead in a small village nearby.
News of the damage was slowed by the fact that much of El Salvador's
telephone service and electricity was knocked out by the quake for
several hours. Only sketchy reports had arrived from many hard-hit
areas.
In Santa Ana, about 35 miles northwest of the capital, the
116-year-old El Calvario church collapsed, killing at least one employee
and possibly others worshipping inside, according to the Rev. Robert
Castro.
The Red Cross reported that 13 people died in nearby Sosonati. Some
200 other victims were rushed to the area hospital, which authorities
weren't sure was still structurally sound.
The quake was centered off the Salvadoran coast, about 65 miles
southwest of San Miguel, according to the U.S. Geological Survey in
Denver, Colo.
It took more than an hour for some San Salvador radio stations to
return to the air and telephone service remained spotty at
mid-afternoon. There were cracked buildings and shattered windows
across the city of 500,000.
Officials at San Salvador's international airport said all flights had been
canceled .
Most businesses in the city closed - though in a surreal touch, acrobats
and dancers from a touring circus marched through the streets past
frightened people, using a loudspeaker to promote a coming
performance.
Police in neighboring Guatemala said a man and a 2-year-old girl were
killed and three other people were injured when a pair of homes
collapsed in the city of Jalpataua.
Local radio stations reported the collapse of a church in Suchitepequez,
in southern Guatemala.
The quake set off car alarms and temporarily knocked out electricity,
radio, television and cellular phone service all over Guatemala, but
most service was quickly restored.
Honduran officials reported cracked buildings in several cities, but there
were no reports of injuries.
A 1986 earthquake centered near San Salvador killed an estimated
1,500 people and injured 8,000.
Topic 2 of 99 [Geo]: Vulcanism
Response 340 of 997: Marcia (MarciaH) * Mon, Jan 15, 2001 (20:12) * 0 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 341 of 997: Marcia (MarciaH) * Mon, Jan 15, 2001 (20:29) * 28 lines
From Rob in New Zealand on http://clubs.yahoo.com/clubs/volcanoesandvolcanologist
Nine caldera volcanoes exist in New Zealand, but seven of them have
been buried by flows of ignimbrite and breccia, mainly from Taupo, but
also Okataina. Other caldera's are Maroa, Whakamaru, Rotorua, and Oruanui.
The latter exists only in name as it borders Taupo, and the more recent
eruptions at Taupo since Oruanui had it's 15 minutes of fame 26500
years have completely wiped it out. It is essentially part of Taupo. All
the caldera's in New Zealand have had a violent history typical of
caldera volcanoes. Parts of Maroa and Whakamaru can still be seen but they
have a least 200 metres of ignimbrite and ash from various eruptions
elsewhere overtop, so all that can be seen is the top of the rim.
Eruptions at Taupo and Okataina will occur again as seismic tests show
that vast magma bodies lie under both. Both have population centres
nearby (Rotorua city - pop. 45000 - 8km from Okataina, and the towns of
Taupo (15000)and Turangi (3500), near Taupo). Ignimbrite flows from
caldera volcanoes have gotten as far as the Manukau Harbour, 150 miles
north-northwest of Taupo. Eight hydro-electric powerstations, two geothermal
stations, and a thermal station use the water of the Waikato river
which drains from Lake Taupo in the caldera. The city of Hamilton (145000
people)is 90 miles from Taupo and is sited on the banks of the Waikato
River. This means 20 percent of the power generation, 40% percent of New
Zealands population, possibly 50% of all tourism, the main trunk
railway and main highway, our only large pulp and paper mill, plus a fair
portion of our dairy, and sheep farming capacity is threatened by the
caldera volcanoes of the North Island.
Topic 2 of 99 [Geo]: Vulcanism
Response 342 of 997: Marcia (MarciaH) * Mon, Jan 15, 2001 (23:47) * 406 lines
Bulletin of the Global Volcanism Network
Volume 25, Number 11, November 2000
Rabaul (Papua New Guinea) Ashfall during August-October most abundant since
1995
Ulawun (Papua New Guinea) An eruption during 28 September-2 October 2000
sends a plume to 1012 km
Langila (Papua New Guinea) Mild Vulcanian eruptions during July-October 2000
Karkar (Papua New Guinea) Rumored eruption on 29 September believed to stem
from Ulawun's ash fall
Manam (Papua New Guinea) Low August-October 2000 activity; increased
seismicity 18 September
Karangetang (Indonesia) February-December included explosions, ash falls,
lava flows, and debris flows
Tengger Caldera (Indonesia) Sudden explosion 29 November; eruption
continues as of 18 December
Merapi (Indonesia) Consistent gas plume; lava avalanches and landslide; new
lava dome and fractures
Slamet (Indonesia) During May-October 2000, continuous tremor and abundant
explosion earthquakes
Kaba (Indonesia) Explosions and light gray ash
Marapi (Indonesia) Large explosions in March 2000 eject ash
Heard Island (Indian Ocean) Discovery of a distinct vent below Mawson Peak;
brown fumes in November
Shiveluch (Kamchatka) Frequent steam plumes, weak tremor, and possible
gasandash explosions
Rabaul
New Britain Island, Papua New Guinea
4.271 S, 152.203 E; summit elev. 688 m
All times are local (= GMT + 10 hours)
This report, which covers the period from August through October 2000,
notes that Vulcanian eruptions prevailed at Tavurvur during 29 August
through October 2000. These eruptions bore far more ash than typical.
Substantial amounts of ash blew towards the city of Rabaul and other
inhabited areas. During the second and third weeks of September the amount
of ash falling reached a maximum since the current eruption began on 28
November 1995.
On 2 and 9 August eruptive plumes contained ash. At other times during
August vent activity was relatively low, consisting only of small volumes
of thin white vapor. The 29 August eruption changed this pattern.
Although the main phase of the 29 August eruption began at 1158, it was
preceded by a series of weak explosions yielding dark gray ash plumes.
After these less-forceful explosive events ended, moderate volumes of dark
gray ash clouds erupted. Subsequently, and through 8 September, the
eruption pattern was comprised of interchanging periods of either
continuous, moderate-volume ash emissions or relatively subdued ash-cloud
emissions typically white to pale gray in color.
At about 2200 on 8 September, the eruption became more intense, frequent,
and discrete explosions producing thick billowing dark ash clouds.
Throughout the rest of September, periods of sub-continuous ash emissions
occurred. After 21 September, however, discrete explosions and
sub-continuous ash emissions declined and continued at a subdued level.
Throughout September, observers saw incandescent lava fragments
occasionally ejected. Residents saw these ejected fragments more frequently
after the onset of explosive activity on 8 September, and around this time
the residents regularly noted audible noises associated with venting.
Explosions every few minutes produced sub-continuous moderate to heavy ash
emissions that continued in October. Some of the larger explosions showered
the N and NE flanks of the volcano with bombs. At night these were seen to
be incandescent (red to dull orange). On inspection most projectiles were
lithic blocks, but a minority were in a plastic state with some bread-crust
surfaces. Jet-aircraft-like roaring from the vent was common and some of
the larger explosions could be heard at distances of over 15 km. Toward the
end of October, the explosions were less forceful, but contained increased
volumes of solid fragments.
All activity during the reporting period appears to have been confined to
the 1941 vent; the 1995 crater issued only white vapor. The current phase
enlarged the vent as a result of explosive activity. The N crater was
breached, forming a saddle-like depression in the rim reaching about 15-20
m lower than the originally symmetrical and level line comprising the ridge.
During the first 2-3 weeks of September ash clouds rose as high as 2 km
above the summit. As previously noted, many plumes blew N and NW to drop
ash on inhabited areas. As a result, many Rabaul businesses were adversely
affected and, by the end of the September, some had moved ~40 km SE of
Rabaul to the settlement of Kokopo. The major health center in Rabaul town
was also affected and patients with respiratory problems were moved to
another health center near Kokopo. During early October the ashfalls caused
patients to undergo evacuation from Nonga Hospital (5 km NNW of Rabaul).
Toward the end of October the annual change in the trade winds caused less
ashfall in Rabaul town; frequent heavy rains around this time also provided
relief from suspended dust.
Seismicity correlated fairly directly with behavior observed at the summit,
and accordingly, seismic activity remained relatively low until the onset
of the eruption. The total number of low-frequency earthquakes recorded
during August was 208, with the largest daily number of 35 on 30 August.
This monthly total was slightly higher than that in July. During the main
episodes of ash eruption between 29 August and 8 September, seismicity was
characterized by bands of non-harmonic volcanic tremor. Bands of volcanic
tremor with reduced amplitude were recorded again during 17-19 September
and, until the end of the month, seismicity included sporadic
short-duration tremor associated with sub-continuous ash ejections.
For August and September, respective high-frequency earthquakes totaled 17
and 8; all occurred NE of Rabaul caldera. The time difference between S-
and P-wave arrivals for these events (S minus P) was 3-6 seconds. Since 28
November 1995, strings or significant numbers of high-frequency NE
earthquakes have correlated with greater summit activity at Tavurvur. The
time interval from the onset of the high-frequency earthquakes to greater
summit activity ranged between one week to a few months. Rabaul's last
major NE earthquake sequence occurred during May-June 2000 (see Bulletin v.
25, no. 7).
During September a total of 3,661 low-frequency earthquakes were recorded.
This total includes explosion earthquakes (with air phases). When like
earthquake records were compared, the September record attained the highest
total since May 1996 (when 3,993 such earthquakes were recorded).
September's highest daily total, 228, was recorded on 11 September; the
lowest total, 3, was recorded on 4 and 7 September, occurring on days when
tremor dominated the seismicity. October seismicity included 2,544
low-frequency earthquakes.
Ground deformation measurements from electronic and wet tiltmeters showed
some caldera inflation from July 1999 to April 2000. After April, the trend
changed to show deflation until about August 2000. Tiltmeters registered
slow inflation during the first few days of September, followed by
subsidence, and then stable conditions on 8 September. Some
deformation-monitoring sites in the area of Tavurvur seemed to indicate a
deflationary trend starting in late September and continuing through October.
Background. The last of two Holocene caldera-forming eruptions of Rabaul
took place 1,400 years ago. Several large historical eruptions have formed
intra-caldera cones. The latest significant eruptive episode, in 1994,
included venting at both the Tavurvur and Vulcan cones. The low-lying
Rabaul caldera forms a sheltered harbor once utilized by New Britain's
largest city. The 8 x 14 km caldera is widely breached on the east, where
its floor is flooded by Blanche Bay. Two major Holocene caldera-forming
eruptions took place as recently as 3,500 and 1,400 years ago. Three small
stratovolcanoes lie outside the northern and NE caldera rims. Post-caldera
eruptions built basaltic-to-dacitic pyroclastic cones on the caldera floor
near the NE and western caldera walls. Several of these, including Vulcan
cone, which was formed during a large eruption in 1878, have produced major
explosive activity during historical time. A powerful explosive eruption in
1994 forced abandonment of Rabaul city.
Information Contacts: Ima Itikarai, David Lolok, Herman Patia, and Steve
Saunders, Rabaul Volcano Observatory (RVO), P.O. Box 386, Rabaul, Papua New
Guinea (Email: rvo@global.net.pg).
Ulawun
New Britain, Papua New Guinea
5.04 S, 151.34 E; summit elev. 2,334 m
All times are local (= GMT + 10 hours)
An eruption from Ulawun that started on 28 September continued until 2
October 2000 (Bulletin v. 25, no. 8). Preliminary information was based on
news media reports and aviation sources. The Rabaul Volcano Observatory
(RVO) has since provided more accurate and detailed reports for the
August-October 2000 period.
Activity during August. During August, summit activity remained low,
chiefly consisting of weak releases of thin white vapor. While the summit
activity remained quiet, some obvious changes were recorded in seismicity
and ground deformation (electronic tiltmeter).
High-frequency earthquakes had occurred sporadically since mid-1998 in very
low numbers (~1/day). A brief period of recording in April 2000 registered
~ 2/day. In mid-June 2000, following the resumption of seismic recording,
high-frequency earthquakes were first seen to have increased to 15-20/day.
This comparatively high number of earthquakes continued through July and
August. Deployment of a portable seismograph during 13-15 August indicated
these earthquakes had epicenters at Ulawun.
During August, low-frequency earthquakes occurred as usual. On about 26
August, both amplitudes and event counts dropped by a factor of three. Also
beginning in August, an electronic tiltmeter located on the flanks ~2.5 km
WSW of the crater vent began to show some inflation on the NS component. By
month-end about 7 mrad of inflationary tilt was recorded. The EW component
(radial to the vent) lacked changes.
Eruption of 28 September-2 October. A relatively small-to-moderate eruption
began on 28 September 2000. Several long-term precursors to the eruption
were unambiguous. High-frequency earthquakes increased dramatically after
June 2000. Electronic tiltmeter trends showed inflation beginning in early
August 2000. Short-term, immediate precursors included an increase in both
the number of low-frequency earthquakes and the real-time seismic amplitude
measurements (RSAM). The latter began to escalate on 27 September 2000.
The late-stage build-up towards the eruption began at 2200 on 27 September
with an increase in low-frequency earthquakes and their amplitudes. A
further increase in seismicity took place at about 0200 on the 28th. There
began a series of small nonharmonic volcanic tremors with durations up to a
few minutes. These increased between 1200 and 1800 on the 28th.
The late-stage buildup also appeared in RSAM readings. RSAM values changed
at 2200 on the 27th from a background level of 2 units, rising at 1200 on
the 28th to ~10 units, then by 1800 to 30 units. After 1800, RSAM values
continued to rise and the instruments registered intense continuous
volcanic tremor. Around this time the RSAM counts exhibited an artificial
decline attributed to an overwhelmed event-counting system.
Other notable changes in the character of the RSAM plot occurred at 2240 on
the 28th, and at 0115 and 0240 on the 29th. The first two times correlated
with behavior noted by the observer watching the summit crater.
Specifically, at 2240 on the 28th the observer saw the first glow
reflecting off an ash-cloud emission. RVO scientists mark this as the
beginning of the eruption. At 0120 on the 29th, production of incandescent
lava fragments intensified, indicating the onset of a Strombolian eruption.
At 0240 on 29 November, the RSAM peaked at 8045 units. Thus, scientists
inferred this as the time when the Strombolian phase of the eruption
peaked. During the cover of darkness, ash clouds were just visible,
initially illuminated by the glow and gradually by incandescent fragments.
The latter became common by about 1200 on the 29th when ash clouds were
seen blowing NW. The ash clouds began to become voluminous from 0100 on the
29th, coinciding with the intensification of the Strombolian phase of the
eruption. The ash clouds were emitted forcefully, accompanied by loud
roaring and rumbling noises.
By first light on 29 September people some distance away from Ulawun were
able to see a thick vertical eruption column that rose ~12-15 km above the
summit (figure 1). In relatively clear morning weather, the eruption column
was visible from Rabaul, ~130 km NE of Ulawun. By this time ash clouds had
blown WSW to NW. Roaring and rumbling noises ceased at about 1000 and
resumed again at about 1300. At about this time also, there was a slight
and brief change in wind direction resulting in the eruption's ash clouds
being redirected to the N and NE.
The eruption produced a moderate amount of ashfall. Ashfall was heavy 10 km
downwind of the vent. Beyond that, the amount of ashfall was much reduced,
lessening still further away from the vent. The ashfall destroyed gardens
and cash-crop plantations within 10 km of its main path. Satellite images
of the ash distribution showed that the ash was blown downwind 80-100 km
from the vent.
The eruption produced three pyroclastic flows. They traveled down
pre-existing gullies on the N, NW, and SE flanks. During past eruptions,
pyroclastic flows also followed the same gullies down from the cone's 2,300
m summit elevation. The N-directed pyroclastic flow was the biggest. It
descended to 580 m elevation. The NW-directed pyroclastic flow was the
second biggest. It divided into two arms at 900 m elevation and its
terminus reached an elevation similar to the one on the N flank. The SE
flow was relatively small. The eruption lacked lava flows.
Scientists inspected the crater area from the air on 7 October and found
two vents on the summit (labeled Vents A and B on figure 2). Comparing Vent
A to its appearance during 1993, the overall depth of the crater floor
appeared to have risen, becoming about 100-150 m shallower. The fill
consisted of older material that collapsed from the inner crater wall and
possibly new ejecta from the current eruption. A prominent breach on the N
crater rim was evident and may have been created by the N pyroclastic flow.
Judging by its close proximity, this flow originated from Vent B.
En-echelon cracks on the E end of the crater suggested inward sagging of
that side of the crater rim. At the time of the inspection, few emissions
escaped the vents; however, traces of white and blue vapor wafted from
other areas inside the crater.
Figure 2. An oblique aerial photo showing Ulawun's summit area and Vents A
and B between 0800 and 0900 on 7 October 2000. Other visible features
include a breach on the NNE crater rim caused by the avalanche of
pyroclastic flow material from Vent B. Photographed by Ima Itikarai;
courtesy of RVO.
There were reports of multiple vents during past eruptions. However, aerial
inspections in 1985 and 1993 only revealed evidence of Vent A. Ulawun had a
flank eruption on the SE side during the 1978 eruption.
RVO staff in Rabaul established communication links with the volcano
observer based near Ulawun at 1606 on 27 September after noting increased
RSAM values. Data from Ulawun were transmitted to RVO every 20 minutes. The
RSAM values led to discussions with civil authorities and directions to
local residents throughout the night at two-hour intervals. During the
process, alert stages one and two were declared. This resulted in
evacuating the local population, an effort accomplished with the help of a
local timber company. Assistance was later provided by the West New Britain
Provincial Government. This time-line of events is contrary to preliminary
information (Bulletin v. 25, no. 8). that relied on local news media.
Activity during October. By 3 October the volcano produced only thin white
vapor with no noise or night glow. Various ancillary observations occurred
in the next weeks: during 6, 8, 10, 14, 15, 16, 17, 18 October and 1
November observers noted low rumbling or banging or both; when under cover
of darkness they usually saw accompanying weak, steady glows. In at least
one case they smelled sulfurous odors.
The noises at 1000 on 1 November accompanied a thick dark ash cloud that
rose 100-200 m above the summit. By 1100 silent ash clouds were seen
forcefully rising ~200 m above the summit. Activity then declined for a few
hours until 1430-1700, an interval when observers saw thick dark gray ash
clouds and occasionally heard weak rumblings. Activity quieted after that
and by 2 November emissions had returned to white vapor without noise or
night glow.
On 13 and 17 October small mudflows occurred, originating on the upper NW
flanks and sweeping down a dry creek through Ubili village and then to the
sea. At certain places the flows spread laterally. No reported damage or
casualties were caused by either mudflow.
October seismicity included tremor and numerous low-frequency earthquakes.
Volcanic tremors were dominant during 1-4, 8-11, and 30-31 October. The
low-frequency earthquakes can be characterized by RSAM data. On 1 October
RSAM stood at ~30-40 units; steady decline brought the 7 October RSAM to ~5
units. On the 8th and 11th there followed peaks of over 20 units. After
that RSAM declined steadily until it reached background levels on 20
October. On 30 October, RSAM underwent a sudden increase to ~20-30 units
heralding the brief 1 November eruption.
The single electronic tiltmeter located on the high WSW flank showed a
steady change throughout October. The behavior could possibly be related to
edifice inflation.
Background. The symmetrical basaltic-to-andesitic Ulawun stratovolcano is
the highest volcano of the Bismarck arc, and one of Papua New Guinea's most
frequently active. Ulawun rises above the N coast of New Britain opposite
Bamus volcano. The upper 1,000 m of the 2,334-m-high volcano is
unvegetated. A prominent E-W-trending escarpment on the S may be the result
of large-scale slumping. Satellitic cones occupy the NW and E flanks. A
steep-walled valley cuts the NW side of the volcano, and a flank lava-flow
complex lies to the S of this valley. Historical eruptions date back to the
beginning of the 18th century. Twentieth-century eruptions were mildly
explosive until 1967, but after 1970 several larger eruptions produced lava
flows and basaltic pyroclastic flows, greatly modifying the summit crater.
Correction: In Bulletin v. 25, no. 8, it was erroneously stated that Ulawun
is also known as the North Son. Ulawun (or Ulavun) is, in fact, sometimes
referred to as The Father. North Son is Mount Likuruanga, a well eroded
cone abutting Ulawun to the NE. This group is completed by Bamus volcano to
Ulawun's SW. Bamus, a 2,000-m-high cone that last erupted in 1886, is
sometimes referred to as South Son.
Information Contacts: RVO (see Rabaul).
Langila
New Britain Island, Papua New Guinea
5.53 S, 148.42 E; summit elev. 1,330 m
All times are local (= GMT + 10 hours)
The mild Vulcanian eruptive activity that occurred at Langila's Crater 2
through June 2000 (Bulletin v. 25, no. 7) continued during July-October
2000. In addition, low-level volcanic activity continued at Crater 3. No
reports of unusual activity were submitted during July and August.
During September, intermittent, mild Vulcanian activity occurred at Crater
2. The activity consisted of moderate emissions of thin-to-thick white
vapor, which were occasionally accompanied by gray ash clouds. On 21, 25,
and 30 September thick, dark gray, convoluting ash clouds were forcefully
released, rose 200 m above the summit, blew to the N and NW, and deposited
fine ash. On 7, 9-11, and 27 September wisps of blue vapor accompanied the
emissions. During the month volcanic activity was low at Crater 3, with
only thin white vapor sporadically visible.
Through October intermittent, mild Vulcanian eruptions continued at Crater
2. The vent usually emitted white vapor, which was sometimes accompanied by
a blue tinge and occasionally by a light ash component. On 8 October a
forceful emission of thick ash rose to 1 km above the crater rim. This
heralded a few days of increased ash emissions, with some forcefully
expelled light gray/brown clouds on the 15th. During 16-24 October
continuous white vapor emissions with a small ash component were common. At
0801 on 24 October a dark gray-to-black ash column rose 1 km above the
crater rim. On 25 October an ash cloud that rose to 2 km above the crater
deposited ash toward the N. Likewise, at 0655 on 26 October a thick, white
vapor plume was accompanied by an ash column that rose to 1 km above the
crater rim. The ash emissions continued throughout the day, and similar
activity occurred the next day. For the rest of the month activity was
confined to white vapor with an occasional ash component. During October
varying amounts of white fume were emitted from Crater 3. Throughout the
period there were no reports of noises or night glow at the volcano; the
seismograph remained out of operation.
Background. Langila, one of the most active volcanoes of New Britain,
consists of a group of four small overlapping composite cones on the lower
eastern flank of the extinct Talawe volcano. Talawe is the highest volcano
in the Cape Gloucester area of NW New Britain. A rectangular, 2.5-km-long
crater is breached widely to the SE; Langila volcano was constructed NE of
the breached crater of Talawe. An extensive lava field reaches the coast on
the N and NE sides of Langila. Frequent mild-to-moderate explosive
eruptions, sometimes accompanied by lava flows, have been recorded since
the 19th century from three active craters at the summit of Langila. The
youngest and smallest crater (Crater 3) was formed in 1960 and has a
diameter of 150 m. The Cape Gloucester observation post, airstrip, and
seismometer are 9 km N of the volcano.
Information Contacts: RVO (see Rabaul).
Karkar
offshore New Guinea, Papua New Guinea
4.65 S, 145.96 E; summit elev. 1,839 m
On 29 September there were reports of light ash fall on the NE coast of
Karkar island, and fine sand deposits were found at the bottom of a
swimming pool. The ash fall led to the rumor that Karkar volcano had
erupted. However, an aerial inspection of the central caldera and Bagiai
cone on 1 October showed that no eruptive activity had taken place.
Volcanologists believe that the ash most likely originated from an eruption
at Ulawun, which, at its peak on 29 September, had an eruption column to
12-15 km altitude. Ash erupted to those heights would have been taken well
into the jet stream and could have been transported to Karkar, which is
located 600 km to the W (downwind at high altitudes) of Ulawun. There have
been no reports of anomalous activity at Karkar since fumarolic gases
killed vegetation in September 1997 (Bulletin v. 22, no. 9).
Background. Karkar is a 19 x 25 km wide, forest-covered island that is
truncated by two nested summit calderas. The 5.5-km-wide outer caldera was
formed during one or more eruptions, the last of which occurred 9,000 years
ago. The excentric 3.2-km-wide inner caldera was formed sometime between
1,500 and 800 years ago. Parasitic cones are present on the northern and
southern flanks of Karkar; a linear array of small cones extends from the
northern rim of the outer caldera nearly to the coast. Most historical
eruptions, which date back to 1643, have originated from Bagiai cone, a
pyroclastic cone constructed within the steep-walled, 300-m-deep inner
caldera. The floor of the caldera is covered by young, mostly unvegetated
lava flows.
Information Contacts: RVO (see Rabaul).
Manam
offshore New Guinea, Papua New Guinea
4.10 S, 145.06 E; summit elev. 1,807 m
Following the 4 June 2000 eruption at Southern Crater (Bulletin v. 25, no.
7), volcanic activity was low at both summit craters through October 2000.
Seismicity remained relatively stable except for a slight increase in
amplitudes beginning on 18 September.
During August, activity at the two summit craters was low. Main Crater
gently emitted small-to-moderate volumes of white vapor, while Southern
Crater weakly emitted white vapor. Seismic-event amplitudes steadily
increased throughout the month, though the overall trend remained within
background levels. Daily average event counts were about 1,200, with some
fluctuations. No significant movements were recorded by the water-tube
tiltmeter 4 km SW of the summit.
Activity remained low throughout September, with vapor emissions from both
craters similar to those in August. Seismic amplitudes were steady until 18
September when a slight increase was observed that continued through the
end of the month. Daily average seismic event counts remained steady, with
about 1,300 events/day.
Throughout October both craters emitted varying amounts of white vapor, and
there were no reports of noise or night glow. Seismicity and tilt
measurements appeared to remain at background levels, although consistent
measurements could not be made because scientists did not have access to
the Tabele Observatory during 5-21 October.
Background. The 10-km-wide island of Manam is one of Papua New Guinea's
most active volcanoes. Four large radial valleys extend from the
unvegetated summit of the conical stratovolcano to its lower flanks. These
"avalanche valleys," regularly spaced 90 apart, channel lava flows and
pyroclastic avalanches that have sometimes reached the coast. Five
satellitic centers are located near the island's shoreline. Two summit
craters are present; both are active, although most historical eruptions
have originated from the southern crater, concentrating eruptive products
during the past century into the SE avalanche valley. Frequent historical
eruptions have been recorded since 1616.
Information Contacts: RVO (see Rabaul).
Topic 2 of 99 [Geo]: Vulcanism
Response 343 of 997: Marcia (MarciaH) * Wed, Jan 17, 2001 (15:34) * 68 lines
************************************
MVO weekly report, 8 December 2000
************************************
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 1 December 2000 to midday, 8 December 2000
Activity at the Soufrière Hills volcano has remained at an elevated level
this week with continued growth of the lava dome.
The level of seismic activity was comparable to last week. The broadband
seismic network recorded a total of 547 rockfall signals, 1
volcano-tectonic, 72 long period and 15 hybrid earthquakes for the
reporting period.
Clear views of the dome were possible throughout the week. The main focus
of activity remains on the eastern flanks, although some small rockfalls
were seen on the western side of the new growth. The buttress of the
1995-98 dome above Tuitt’s Ghaut is being eroded away and engulfed by the
new dome growth behind. Rockfalls and small pyroclastic flows are now
regularly travelling down the upper reaches of Tuitt’s Ghaut. The notch
between the central and northeastern buttresses of the 1995-98 dome is now
60 m or 200 feet wide. Intense dome glow was seen throughout the week,
both from the east at Jackboy Hill and the west at Salem and Frith’s.
Spines are continuously growing and collapsing on the summit of the dome.
On 5 December, the top of a spine was at a height of 1060 m or 3480 feet,
and the flat top of the main dome was between 1020 and 1030 m height, that
is between 3350 and 3380 feet.
Measurements of sulphur dioxide emissions from the volcano were not
possible this week due to ashy conditions.
Andy Eby and Lizzette Rodriguez from the University of Puerto Rico
continued their collaboration with the MVO this week. Measurements of sites
at Galway’s, Roche’s, St. George’s Hill, Lookout and Reid’s Hill were made
throughout the week. These data continue a long time series of measurements
made by the University of Puerto Rico over the past 5 years in conjunction
with the MVO. Measurements have been made about every 3-4 months during
this period, and provide useful information on the long-term deformation of
the volcano.
Residents of Montserrat and visitors to the island are advised to tune in
to ZJB Radio for up-to-date information on the status of the volcano.
Rockfall and pyroclastic flow activity is likely to remain at a high level
whilst the dome continues to grow, producing ash clouds which may blow over
inhabited areas if winds are from the south or southeast. Elevated levels
of pyroclastic flow activity may develop very rapidly and could affect any
valleys around the volcano. In addition to the risk from pyroclastic flows,
the Belham valley should also be avoided during and after periods of heavy
rain. Ash masks should be worn in ashy conditions or when you disturb ash.
Everyone is reminded that access to Plymouth, Bramble airport and beyond is
prohibited. There is a maritime exclusion zone around the southern part of
the island that extends two miles beyond the coastline from Trant’s Bay in
the east to Garibaldi Hill on the west coast. The daytime entry zone
remains closed.
12 noon, Friday, 8 December 2000
Check out our web pages for recent pictures of the dome, including the
large spine from 17 November.
Dr Gill Norton
Director
Montserrat Volcano Observatory
Mongo Hill
Montserrat
West Indies
Topic 2 of 99 [Geo]: Vulcanism
Response 344 of 997: Marcia (MarciaH) * Wed, Jan 17, 2001 (18:18) * 28 lines
MIYAKEJIMA VOLCANO, South of Tokyo
(Oyama 813 m, 34o04'43"N, 139o31'46"E)
(10/16/00)
According to JMA, Geological Survey of Japan, and Tokyo Institute of Technology, SO2 flux from the craters within the Miyakejima
summit caldera has still continued in high level; 30,000-50,000ton/day. Ash had been emitted continuously in early-September and
intermittently in late-September. The subsidence had not been clear after mid-August, although partial collapses of the northern cliff of
the caldera took place in late-September. A large pyroclastic cone inclined the southern cliff of the caldera, on which steaming craters
are located. The present altitude of the caldera floor is about 230 m according to the laser-distance meter survey from helicopter by
ERI.
As SO2 was too high, the Tokyo Metropolitan government to which the Miyakejima belongs decided that nobody stayed in the
island during night. By the early October, public workers and researchers had stayed in a boat floating near harbors (hotel-ship
system) and landed at the island in daytime. P3C of the Maritime Safety Department watched the activity during the operation. In the
early October, the hotel-ship system also stopped and public workers and researchers commuted by small boats between
Miyakejima and Kozu-shima, the nearest island to the former. Operation was limited along the road running the coastline, for a short
time, only when clear sky, and depending on the direction of the wind.
Electric power was cut when workers of the electric company did not stay in the island, so that most of monitoring equipment was
down in night and cloudy-rainy days. Though Earthquake Research Insatiate, University of Tokyo, and other national institutes kept
the gathering the real-time data, their aims were hardly filled.
Excellent images and great links: http://hakone.eri.u-tokyo.ac.jp/vrc/erup/miyake.html
(thanks Ian...)
Topic 2 of 99 [Geo]: Vulcanism
Response 345 of 997: Marcia (MarciaH) * Wed, Jan 17, 2001 (19:49) * 68 lines
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Mayon Volcano, Philippines
******************************
Subject: Mayon activity continues as of 15 January.
New dome began growing at Mayon on ~8 January. Aerial observations on 10
January found the dome to have a spiny, blocky surface as the crater floor
is being pushed up by the ascending magma. Voluminous steaming, slight
incandescence and heightened SO2 rates are being noted, as well as
increased seismicity. N flank of edifice is inflating. This activity still
ongoing as of 15 January.
Below from: http://www.phivolcs.dost.gov.ph/Volcanoes/Mayon/MayonIndex.html
Mayon Volcano Bulletin
8:00 AM, 12 January 2001
An aerial survey conducted on 10 January with the help of AFP confirmed the
presence of a lava dome inside the summit crater. The lava dome appeared to
have a spiny, blocky surface, which resulted from the crater floor being
pushed upward by magma beneath the crater. The lava dome is emitting
voluminous steaming and is the source of slight incandescence. The Sulfur
Dioxide (SO2) emission rate determined by the PHIVOLCS Correlation
Spectrometer (COSPEC) is 2,300 tonnes per day (t/d), which is way above the
500 t/d output usually observed Mayon's quiescent periods.
Earthquake activity related to lava dome growth remains significant. In the
past 24 hours, fifteen (15) low frequency-type volcanic earthquakes were
detected indicating that magma ascent is still ongoing. For reference, the
usual number of earthquakes recorded during repose is generally less than
five (5) events. Ground deformation being measured by electronic tiltmeters
deployed on the northern flank of the cone continues to report ongoing
tilting, also signifying intrusion of magma into the upper levels of the
volcano.
The above observations strongly suggest that magmatic ascent is in
progress. PHIVOLCS reminds the public that Alert Level 2 remains in effect.
A full-scale eruption, however, is still not evident because the trend in
monitored parameters have not yet attained critical levels. The six (6)
kilometer radius Permanent Danger Zone (PDZ) must therefore be off-limits
at all times because sudden explosions may occur as a result of hot lava
deposits in the crate area encountering groundwater. Visits within the PDZ
are also prohibited, especially treks to the summit area. PHIVOLCS also
suggests that residents near major river channels be extra alert against
possible volcanic mudflows, landslides and rockfalls that may result from
volcanic debris deslodged or eroded from the upper slopes.
PHIVOLCS
--------
Mayon Volcano Bulletin
8:00 AM, 15 January 2001
Earthquake activity generally remained at higher-than-usual levels. The
Mayon seismic network detected forty-seven (47) low frequency-type volcanic
earthquakes on 13 January and seismicity has been significantly high since
the lava dome was observed on 08 January.
Electronic tiltmeters deployed on the northern flank of the volcano
indicates sustained inflation of the edifice. This is corroborated by the
above-normal Sulfur Dioxide (SO2) outputs that were recorded in the past
week. These observations could be an indication of a magmatic intrusion.
Steaming activity was noted to be vigorous since the appearance of the lava
dome and crater glow was still visible at Intensity 1 (perceptible only
with the aid of a telescope). However, thick rain clouds obscured most of
the volcano since 14 January up to this writing.
Alert Level 2, which means sustained unrest with indications of magmatic
activity remains in effect. PHIVOLCS reminds the public to avoid the six
(6) kilometer-radius Permanent Danger Zone (PDZ) and that treks near the
summit is prohibited. Residents near river channels that originate from the
volcano are advised to be always aware of lahars, which may form during
heavy rains.
PHIVOLCS
Topic 2 of 99 [Geo]: Vulcanism
Response 346 of 997: Marcia (MarciaH) * Fri, Jan 19, 2001 (14:34) * 37 lines
*****************************************
University of Hawai'i faculty position
*****************************************
From: Mike Garcia
Faculty Position in Volcanology
The University of Hawai'i Department of Geology & Geophysics, School of
Ocean and Earth Science and Technology (SOEST) invites applications for a
tenure-track faculty position in the general area of volcanology.
We are seeking candidates to augment and complement current department
research in igneous petrology, geochemistry and volcanology. Applicants
with expertise in quantification of magmatic processes (including melting
and magma transport, magma chamber and conduit processes, eruption
dynamics, and geochemical cycles) are especially encouraged to apply.
The successful applicants will join a large, dynamic research group and
will be expected to interact with numerous other Earth scientists within
SOEST. We expect to fill positions at the Assistant Professor level but
exceptional candidates at more advanced levels will be considered. Starting
salaries for these 9-month appointments will be dependent on qualifications
and experience. The successful candidates will be expected to develop
outstanding research programs, and to teach at the graduate and
undergraduate levels. Requirements for both positions include a PhD in
geology or related fields, and evidence of scientific research excellence
and teaching ability. Rank to be determined by qualifications and
experience. The anticipated starting date is August 2001, subject to
position clearance.
Applicants should send a curriculum vitae, a list of publications, a
summary of research and teaching interests, and addresses, phone-numbers
and email of three or more references to Volcanology Search, Department of
Geology and Geophysics, University of Hawaii, 1680 East-West Road,
Honolulu, Hawaii 96822 USA. Recruitment will continue until the positions
are filled.
To ensure full consideration applications should be sent immediately. The
search committee has already began to review applications. Information
about the Department can be found at website: www.soest.hawaii.edu/GG/.
Topic 2 of 99 [Geo]: Vulcanism
Response 347 of 997: Marcia (MarciaH) * Sun, Jan 21, 2001 (15:12) * 72 lines
************************************
Indonesia update, 9-15 January 2001
************************************
The Volcanological Survey of Indonesia reports that for the week of 9-15
January Merapi showed a much higher level of activity and the Alert Status
was raised to 3 on the 10th. There are ash plumes, lava avalanches and
pyroclastic flows (to 4km in length). The avalanches and pyroclastic flows
are nearly continuous. Minor explosions occurred at Inelika (Flores
Island), increased activity at Java's Semeru (explosions and avalanches),
minor explosion at Api Siau, ongoing minor ash emissions at Lokon-Empung
were also noted in this report.
Following from: http://www.vsi.dpe.go.id/news/index.html
Weekly Report No. 598
9-15 January 2001
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Merapi actiity is ongoing and higher than previously, and the level has
changed to level 3 since 10 January at 06.00 o'clock. It was represents
from both visual and instrumental monitoring.
Visual observations noted, ash plume was commonly in white thin-thick
color, low in pressure, rose 500 m height above the summit. Glowing lava
avalanche is continuing, flowed to the upstream of River Sat, Lamat and
Senowo. The total runout length was 2000 m. Pyroclastic flow occurred 29
events on 14 January 2001 and filled River Sat, Lamat and Senowo with the
maximum distance about 4000 m. During this week glowing lava avalanche and
pyroclastic flow occurred continuously with the interval of 0.5 - 1 hours.
Merapi volcano is in level 3.
Inelika
Central Flores; 8°44' S, 120°59' E
Minor explosion occurred on 11 January 2001 at 19.15 WITA (local time).
This explosion produced ash material which has the thickness less than 0.5
mm in Bajawa (about 8 km from the source). With the increasing activity
since 11 January 2001 Inelika is stated in level 3.
On 13 January 2001 at 07.00 WITA was seen 3 events of explosion. Ash
explosion hit about 300-1000 m height above crater rim. This product has
been blown eastward to the Toa village and southward to the Boya village,
Bajawa and Bolodio city. Thundering sound was heard from post observatory
(about 7.5 km to the summit). The color of ash is white thick.
Seismograph recorded continuous tremor earthquake with the amplitude of 2
mm and 59 events of explosion earthquake during the period. The amplitude
of explosion earthquake is 2-14 mm.
Inelika volcano is in level 3.
Semeru
East Java; 8°6.50' S, 112°55' E
There is significant increasing in seismicity, especially in deep volcanic
(A) earthquake. Total seismicity during the report were: 29 event of deep
volcanic (A), 1 event of shallow volcanic (B), explosion 693 events,
avalanche 80 events, and 4 events of tectonic earthquake.
The alert level of Semeru volcano is in level 2.
Karangetang
Siau island; 2°47' N, 125°29' E
One event of minor explosion occurred on 10 January, produced ash which
felt into the crater. Here is a list of seismicity: deep volcanic (A) 7
events, multiphase 5 events, explosion 1 event, tectonic 89 events.
Karangetang volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
Based on visual and instrumental observations there is no substantial
change in Lokon volcano. Ash plume from crater rose 50-200 m height.
Seismograph is continuing to record uncontinuous tremor which has 0.5-6 mm
amplitude. Complete data were listed as follow: 12 events of deep volcanic
(A), 22 events of shallow volcanic (B), 27 events of tectonic earthquake
and uncontinuous tremor earthquake.
Lokon volcano is in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 348 of 997: Marcia (MarciaH) * Tue, Jan 23, 2001 (00:00) * 22 lines
Mexico Volcano Spews Huge Column of Ash, Smoke
MEXICO CITY (Reuters) - Mexico's Popocatepetl volcano, whose
December eruptions forced the evacuation of 41,000 villagers, on
Monday spewed an five-mile column of ash and smoke skyward,
authorities said.
"It's a huge mushroom cloud," said Carlos Valdez, an official with the
National Disaster Prevention Center.
The outburst blackened the sky over Puebla, a city of about two million
about 25 miles east of "Popo," as most Mexicans call the 17,884-foot
volcano.
The huge column also dominated the afternoon skyline in
Mexico City, home to some 18 million residents and located just 40
miles from the volcano.
But unlike December's eruptions, there were no showers of molten rock
from the volcano.
Evacuated villagers returned home shortly before the New Year and
there were no new evacuations immediately planned due to Monday's
activity, officials said.
However, residents were warned to keep outside of a 7.5-mile radius of
Popocatepetl (pronounced poh-poh-kah-TEH-peh-til), whose name
means "smoking mountain" in the indigenous Nahuatl tongue.
Topic 2 of 99 [Geo]: Vulcanism
Response 349 of 997: Marcia (MarciaH) * Wed, Jan 24, 2001 (23:02) * 123 lines
***********************
Popocatepetl, Mexico
***********************
From: Dan Shackelford
Subject: Strong eruption at Popocatepetl with pyroclastic flows.
(http://www.cenapred.unam.mx/boletines.html)
JAN 22 22:15 (04:15 Jan 22 GMT)
After a period of several weeks of quietness, today, in the afternoon,
Popocatepelt volcano increased its activity levels. At 14:58 a volcano
tectonic earthquake of magnitude 2.8 was detected on the East flank. The
event was possobly the precursor of a large exhalation that started at
16:15, producing an ash plume that reached several kilometers of height.
At 16:23 a more explosive phase was observed, and some incandescent
fragmets were ejected, and fell around the crater. After several minutes
several piroclastic flows were generated, and came down in several ravines
up to 4-6 Km. These flows, were visible in the North flank using our video
camera.
(EGO)
It is recommended not to approach the volcano to less than 12 km from the
crater.
The traffic light of volcanic alert remains yellow-3.
***********************
Mayon, Philippines
***********************
From: Dan Shackelford
Subject: Mayon restlessness persists.
Following a two day lull in seismicity, Mayon returned to higher seismic
levels on 18-19 January, reflecting continued inflation and summit lava
dome activity. SO2 was measured at 1700 tonnes/day on the 17th.
From: http://www.phivolcs.dost.gov.ph/vmepd/updates/mv010901.htm
Mayon Volcano Bulletin
12:00 NN 19 January 2001
After a brief respite in earthquake activity during the past two (2) days,
the monitoring network again recorded high seismic levels. Thirty-six (36)
low frequency-type volcanic earthquakes occurred in the past 24 hours,
which is probably caused by continued magma movement beneath the summit
lava dome. Tiltmeter records continue to show the inflationary trend
brought about by magma intrusion into shallow levels of the volcanic cone.
However, because of the prolonged rain and cloud cover during the past
week, dome activity could not be confirmed by visuals. The latest Sulfur
Dioxide output measured on 17 January was 1,700 tonnes per day, which is
higher than the background level and also reflects the restive state of the
volcano.
Alert Level 2, which means sustained unrest with indication of magmatic
activity remains in effect. PHIVOLCS reminds the public to avoid the
six(6)-kilometer radius Permanent Danger Zone (PDZ). In addition, treks
near the summit are prohibited due to possible sudden phreatic or
steam-driven explosions from the summit crater. Residents near river
channels that originate from the volcano are also advised to be always
aware of lahars, which may form during heavy rains.
PHIVOLCS
***********************
Santa Ana, El Salvador
***********************
It appears that there was no Santa Ana in El Salvador,
From: Alain Bernard
Subject: No Santa Ana eruption
Dear Volcanophiles,
There is no eruption of Santa Ana only an intensification of the
degassing from an active fumarolic area close to the crater lake.
Concern about health hazards due to an increase in the emission of
volcanic gases from Santa Ana was recently reported in the local
newspaper El diario de Hoy on January 12 (so one day before the
major quake). The archives can be consulted at
http://www.elsalvador.com/noticias/EDICIONESANTERIORES/
On January 18, Jim Vallance, Carlos Pullinger and Demetrio
Escobar flew over the volcano and found no evidence of new lava
inside the crater. The small crater lake (200m in diameter) was still
observed. Only glowing rocks were observed in the fumarolic field
due to relatively high temperature (523C in January 2000) of the
fumaroles.
see http://www.laprensa.com.sv/nacionales/nac7.asp
Changes in the degassing activity of Santa Ana was first reported
by Demetrio who observed an increase in the degassing in May
2000. At that time,the temperature of the lake rose from 18-19 to
30C.
Analyses of lake waters collected in July and August showed only a
slight increase in chlorides and sulfates but no change in pH (0.9)
or in Delta 34S compared to January 2000.
A. Bernard
Alain Bernard
BRUEGEL (Brussels Unit for Environmental,
Geochemical and Life Sciences Studies)
Université Libre de Bruxelles
160/02
50, Ave. Roosevelt
1050 Brussels Belgium
Ph:32/2/6502253
FAX:32/2/6502243
email: abernard@ulb.ac.be
-----
Subject: No eruption at Santa Ana
I learned late this weekend that there was NOT an eruption at Santa Ana
volcano in El Salvador. See the following URLs:
http://www.elsalvador.com/noticias/NACIONAL/nacio42.html (with a nice pic
of the crater and NEW fumarolic area)
Also: http://www.laprensa.com.sv/nacionales/nac1.asp
(There are places on the web that will translate for you ... I use
http://www.worldlingo.com or http://translator.go.com usually)
Topic 2 of 99 [Geo]: Vulcanism
Response 350 of 997: Marcia (MarciaH) * Wed, Jan 24, 2001 (23:04) * 99 lines
*****************************************************
Updates for Indonesian volcanoes, 16-22 January 2001
*****************************************************
From: Dan Shackelford
For the week of 16-22 January, Merapi volcano continued its trend of
increasing activity, marked by numerous pyroclastic flows, lava avalanches
and incandescent lava flows. Along with heightened seismic levels, a new
lava dome ("lava Dome 2001") has formed on the summit in the shattered
remnants of Dome 1998. Also during this week, remote Flores Island volcano
Inielika continued to erupt ash to 1,000m from two vents within the crater
(NW-SE line), while Api Siau (Karangetang) experienced a minor explosion on
the 17th and lava avalanches occurred as well. Lokon-Empung showed
increased earthquake activity and an ash plume to 250m. The infamous Kelut
volcano showed increasing lake temperatures and inflation, prompting an
increase to Level 2 (alert level) on the 19th.
Source: http://www.vsi.dpe.go.id/news/index.html
Weekly Report No. 599
16-22 January 2001
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Activity on merapi volcano is continuing and increase. That was represents
from visual and instrumental monitoring. Visual observation from many post
observatory showed that the active Merapi continued to erupt produced many
pyroclastic flow, ash, glowing lava flow and lava avalanche. This eruption
tend to increase, was marked with an increasing of seismicity, especially
in avalanche and multiphase earthquakes. Pyroclastic flow occurred
continuously more than 20 events per day traveled to the River Sat
(upstream of River Putih), Senowo, and Bebeng. The maximum distance is 4500
m to the River Sat and 3000 m to the River Bebeng. Glowing lava avalanche
activity has increased substantially this week traveled to the River Sat,
Senowo, and Bebeng as far as 3500 m, and suggested sourcing from many
point. Observer also noted that glowing lava avalanche occurred more than
150 events a day. They also noted that has growth a new lava dome which
called "Lava Dome 2001" on Merapi summit which lay on lava dome 1998 which
has broken few days before. The growing of the new lava dome is ongoing and
showed glowing around the dome at night sight. Pyroclastic flow which
occurred recently predicted sourcing from the new unstable dome. Ash rain
occurred surround Babadan, Ngepos and Kaliurang.
During the week solfatara is in white-thick color, medium-high pressure,
rose 850-1300 m height, and an average is about 95 ton/day. EDM measurement
could not be done because the reflector covered by ash. Seismograph
recorded 226 events of multiphase, 683 events of avalanche, 139 events of
pyroclastic flow and 2 events of tectonic earthquake.
Merapi volcano is in level 3.
Inelika
Central Flores; 8°44' S, 120°59' E
Ash explosion is ongoing reached 100-1000 m above crater rim. Observation
to the crater by VSI staffs on 21 January 2001 noted has occurred 2 new big
crater trending to southeast and northwest. Southeast crater has a hole
with diameter about 50 m and 10 m depth. The bottom of the crater has 25 m
of diameter and has closed. Ash plume appear from northern wall crater,
blew away to the south, low-high pressure. Around the crater was heard a
noising sound. The northwest crater has 20 m of diameter opened to the
northwest with the depth is 1.10 m. Ash plume eject vertically, and the
bottom of the crater has closed. Solfatara smelt low and was heard a low
noising sound. Material explosion contains ash and lapili. Ash is in light
grey color, felt around the crater with radius is about 10-20 m. Maximum
diameter of lapili is 50 cm. Lapili felt around the crater, the distance
about 500 m. Solfatara temperatur is 95°C, meanwhile ground temperatur near
solfata location is 89°C.
Inelika volcano is in level 3.
Karangetang
Siau island; 2°47' N, 125°29' E
On 17 January (08.45 WITA) has occurred a minor explosion produced ash and
lava avalanche. Ash felt down around Salili and Beong village, meanwhile
lava avalanche flowed to the east and west. Here is a list of seismicity:
deep volcanic (A) 8 events, 3 events of shallow volcanic (B), multiphase 9
events, explosion 1 event, tectonic 84 events, and 16 events of tremor
earthquake.
Karangetang volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
No major change was shown in Lokon volcano. White thin-thick ash plume rose
50-250 m above the crater. Seismograph recorded an increasing earthquake
especially in volcanic earthquake. Complete data were listed as follow: 77
events of deep volcanic (A), 62 events of shallow volcanic (B), 35 events
of tectonic earthquake and uncontinuous tremor earthquake with the
amplitude of 0.5-2.6 mm.
Lokon volcano is in level 2.
Kelut
East Java;7°56' S, 112°18.5' E
Kelut indicating an increasing activity during the period and since 19
January 2001 the alert level was changed from level 1 (normal active) to
the level 2. An increasing marked with an increasing of water crater lake
temperature, is about 47.5-49.1°C. Meanwhile the temperature average near
inlet is 47.5°C. Leveling measurement showed an inflation about 5.5-6 mm,
and on 21 January water level increased 5 cm. During the period seismograph
recorded 20 events of tectonic earthquake.
Topic 2 of 99 [Geo]: Vulcanism
Response 351 of 997: Marcia (MarciaH) * Wed, Jan 24, 2001 (23:06) * 59 lines
*************************************
Scientific and Hazards Assessment -
Soufrière Hills Volcano, Montserrat
*************************************
From: Dr Gill Norton
Subject: Preliminary statement from Risk and Hazard Assessment meeting,
Montserrat, 18 January 2001
SCIENTIFIC AND HAZARDS ASSESSMENT OF THE SOUFRIERE HILLS VOLCANO, MONTSERRAT
Preliminary Statement (18 January 2001)
The Soufrière Hills Volcano has entered into a second episode of prolonged
and vigorous dome growth. Since November 1999 the dome has grown at an
average rate of nearly 3 cubic metres per second. Growth was interrupted on
20 March 2000 by a major dome collapse, but otherwise growth has been
continuous. The dome is now at its largest size since the eruption began in
1995. It now has a total volume of over 120 million cubic metres and an
elevation of over 1000 metres above sea level.
For several months the direction of dome growth has been predominantly
towards the east with typically hundreds of rockfalls occurring per week,
mainly down the side of the dome towards the Tar River. This is the
configuration at the time of this statement. Further collapses and
pyroclastic flows are anticipated and are most likely to move down the Tar
River. These are unlikely to pose a direct threat to areas outside the
Exclusion Zone, but might result in ash fall in populated areas. Given the
present configuration of the dome, the risk to populated areas on
Montserrat is considered very low. However, in the event of a shift in the
direction of dome growth towards the north or west, as has happened in the
past, this would immediately make the Belham Valley an area of high risk.
Such a shift could happen at any time, over a period of a few hours to
days. Under such circumstances, the areas bordering the Belham Valley would
become vulnerable to pyroclastic flow hazards. If the main direction of
dome growth then persists towards the northern sector, other areas south of
the Nantes River might become vulnerable.
Observations of dome growth rates, seismicity and gas release rates
indicate that the volcano is now in a period of sustained eruption and it
is unlikely that the eruption will cease within the next 6 months. The most
likely prognosis is for at least a few more years of this type of activity.
However, there are increasing indications that the Soufrière Hills Volcano
is evolving into a persistently active state and may continue to erupt,
either continuously or intermittently, for an even longer time. Further
activity of the kind experienced in 1995-1998, including dome collapses,
pyroclastic flows, explosive activity, ash fall, and mudflows in periods of
high rainfall, is likely.
Dr Gill Norton
Director
Montserrat Volcano Observatory
Mongo Hill
Montserrat
West Indies
ph: +1-664-491-5647
fax: +1-664-491-2423
email1: gill@mvomrat.com
email2: gen@bgs.ac.uk
email3: gillnorton@yahoo.com
Topic 2 of 99 [Geo]: Vulcanism
Response 352 of 997: Marcia (MarciaH) * Thu, Feb 1, 2001 (18:48) * 281 lines
Date: Wed, 31 Jan 2001 09:51:51 +0000
From: Lisa Koenig
Subject: GVP/USGS Weekly Volcanic Activity Report 24-30 Jan 2001
Sender: VOLCANO
X-Sender: lkoenig@imap4.asu.edu
Approved-by: Lisa Koenig
To: VOLCANO@asu.edu
Reply-to: VOLCANO
X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32)
******************************************
GVP/USGS Weekly Volcanic Activity Report
24-30 Jan 2001
******************************************
From: Gari Mayberry
Weekly Volcanic Activity Report
24-30 January 2001
New Activity/Unrest: | Fuji, Japan | Mayon, Philippines | Merapi, Indonesia |
Ongoing Activity: | Etna, Italy | Kilauea, USA | Popocatépetl, México |
Shiveluch, Kamchatka | Soufrière Hills, Montserrat |
New Activity
FUJI Honshu, Japan 35.35°N, 138.73°E; summit elev. 3,776 m
According to a Reuters article from 29 January, the high number of
low-frequency earthquakes that were recorded at Fuji over the past several
months (133 in October, 222 in November, and 144 in December) decreased to
36 in January.
Background. The conical form of Fuji-san, Japan's highest and most noted
volcano, belies its complex origin. The modern postglacial stratovolcano is
constructed above a group of overlapping volcanoes, remnants of which form
irregularities on Fuji's profile. Growth of the Younger Fuji volcano began
with a period of voluminous lava flows from 11,000 to 8,000 years before
present (BP), accounting for four-fifths of the volume of the Younger Fuji
volcano. During the late Holocene, summit eruptions dominated from 3,000
to 2,000 BP, after which flank vents were active. The extensive basaltic
lava flows from the summit and some of the more than 100 flank cones and
vents blocked drainages against the Tertiary Misaka Mountains on the N side
of the volcano, forming the Fuji Five Lakes, popular resort destinations.
The last eruption of this dominantly basaltic volcano in 1707 was Fuji's
largest during historical time. It deposited ash on Edo (Tokyo) and formed
a large new crater on the east flank.
Source: Reuters,
http://www.enn.com/news/wire-stories/2001/01/01292001/reu_fuji_41678.asp
Fuji Reports
from
the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
PHIVOLCS reported that the increase in volcanic activity, which has
occurred since a lava dome was spotted in Mayon’s summit crater on 10
January, led them to raise the Alert Level from 2 to 3 (an increased
tendency towards eruption, with magmatic outbursts possible within the
coming weeks) on 25 January. During the previous week the monitoring
networks had detected numerous volcanic earthquakes, continued inflation at
the edifice, and very high gas emission from the summit crater (5,040
metric tons per day). In addition, several ash ejections coincided with
earthquakes that originated from beneath the lava dome, which appeared to
grow during the week. The ash-laden volcanic plumes typically rose up to
500 m above the crater and generally drifted with the prevailing wind to
the WNW and NW.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon's most violent eruption, in 1814,
killed more than 1,200 people and buried an entire town in volcanic mud.
Eruptions that began in February 2000 led PHIVOLCS to recommend the
evacuation of people within 7 km of the summit in the SE and within 6 km
for the rest of the volcano on 23 February.
Sources: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
Associated Press
http://dailynews.yahoo.com/h/ap/20010126/wl/philippines_volcano_2.html
Mayon Reports
from
the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
An Associated Press article from 25 January reported that ash mixed with
rain fell on the village of Deres on the flanks of the volcano. Activity
reportedly increased slightly on 25 January.
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory
(MVO) of the Volcanological Survey of Indonesia.
Source: Associated Press
http://www.washingtonpost.com/wp-srv/aponline/20010125/aponline053616_000.htm
Merapi reports
from
the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
POSEIDON reported that during 22-28 January, eruptive activity at Etna was
dominated by modest, intermittent lava flows that were emitted from the
radial fracture on the N flank of the Southeast Crater. The Bocca Nuova
Crater mostly produced ash-and-gas emissions during the beginning of the
report period, but they decreased near the end of the period. At night,
weak Strombolian activity was observed inside the crater. Limited gas
emissions were released from the Northeast and Voragine craters.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, NE Crater, and SE Crater. Flank eruptions, typically with higher
effusion rates, occur less frequently and originate from fissures that open
progressively downward from near the summit. A period of more intense
intermittent explosive eruptions from Etna’s summit craters began in 1995.
Source: Sistema Poseidon http://www.poseidon.nti.it/IndexDinamiche.htm
Etna Reports
from
the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Surface lava flow activity on Pulama pali gradually declined during 27 and
28 January, with only two flows near the E and W sides of the flow field.
By 29 January, the area where lava entered the ocean was relatively large
and a small bench (land built out from the sea cliff) was being
constructed. Overall, volcanic tremor near Pu`u `O`o and in Kilauea`s
caldera was at low-to-moderate levels. Tiltmeters in the summit area and
along the east rift zone showed no deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes.
Historically its eruptions originate primarily from the summit caldera or
along one of the lengthy E and SW rift zones that extend from the caldera
to the sea. The latest Kilauea eruption began in January 1983 along the E
rift zone. The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and
55th eruptive episode. Since 1986, flows have traveled 11-12 km from the
vents to the sea, paving about 80 km2 of land on the S flank of Kilauea and
building 205 hectares of new land.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
POPOCATEPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= GMT 6 hours)
During the week several small-to-moderate sized eruptions occurred, with
light ashfall reported in two towns and a pyroclastic flow stopping 8 km
short of a town. The Washington VAAC reported that on 25 January an ash
plume, which was produced by rockfall activity, rose to ~7 km a.s.l and was
visible on GOES-8 imagery. According to CENAPRED, at 1338 on the same day
an exhalation produced an ash cloud that rose to 3 km above the volcano and
blew to the NW, depositing ash in San Pedro Nexapa, ~15 away. A minor
eruption at 1212 on 27 January produced an ash cloud that rose to 6.4 km
a.s.l. and blew to the NE, depositing light ash in the town of Santiago
Xalitzintla, ~15 km from the volcano. An ash-and-steam eruption at 1155 on
28 January produced an ash cloud that that rose to 7 km and blew to the NE.
Based on information from the Mexico City MWO, the Washington VAAC reported
that an eruption occurred at 1104 on 29 January. A pilot report stated that
the ash cloud from the eruption rose to ~11.9 km a.s.l., while CENAPRED
reported that the cloud rose to ~8 km a.s.l. and blew to the NE. The
eruption sent pyroclasts out to 1 km from the crater and produced
pyroclastic flows that traveled down the NE flank of the volcano, stopping
8 km before reaching the town of Santiago Xalitzintla. The pyroclastic
flows caused some melting of the summit glacier located primarily on the
upper N and W flanks. The volcano remained at Alert Level Yellow Phase III,
with a 12-km-radius restricted area.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava
domes have incrementally been constructed within the summit crater and
destroyed by explosive eruptions. Intermittent small-to-moderate
gas-and-ash eruptions have continued, occasionally producing ashfall in
neighboring towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Sources: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Associated Press
http://www0.mercurycenter.com/premium/world/docs/volcano27.htm
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m; All times are local (= GMT + 12 hours)
KVERT reported that on 21-24 January seismicity was above background levels
and on 20-24 January a gas-and-steam plume rose 50-1,000 m above the
volcano. Shallow earthquakes were registered under the volcano along with
short-lived explosions at 0444 on 22 January and at 0924 on 24 January. The
Concern Color Code
remained at Yellow.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large breached caldera formed by collapse of the
massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo3/update/kvert.htm
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
SOUFRIERE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,052 m
Activity at the Soufrière Hills volcano during 19-26 January was lower than
the previous week, although the lava dome exhibited continued growth.
Compared to last week, seismic activity was reduced and the number of
rockfalls more than halved. Activity continued to be concentrated on the SE
side of the lava dome, with a large slabby lobe extruded above the Tar
River Valley, which is to the E of the volcano.
Background. The complex andesitic Soufriere Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that initially
forced evacuation of the southern half of the island and then destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvomrat.com/
Soufriere Hills Reports
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 353 of 997: Marcia (MarciaH) * Fri, Feb 2, 2001 (11:30) * 35 lines
*********************
Merapi, Indonesia
*********************
From: Dan Shackelford
Subject: Dome Collapse at Merapi volcano on 28 January.
Partial collapse of Merapi's Lava Dome 2001 on 28 January 2001 led to
continuous pyroclastic flows and lava avalanches at 2-5 minute intervals
down the SW and W flanks for up to 4.5km. Increased activity began on 27
January. Thick ash plumes rose to 2000m above the summit, with thunderings.
This increased activity still persisting as of the 31 January report.
From: http://www.vsi.dpe.go.id/news/index.html (31 January 2001)
Merapi Update
31 January 2001
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Merapi lava dome 2001 collapsed partially on Sunday, 28 January, 2001
resulting pyroclastic flow and molten lava avalanche which occured
continuously, with interval about 2-5 menits. Lava and pyroclastic flow
material entering to the River Sat in the southwest, Senowo in the westward
and Bebeng in southwest. The maximum runout is about 4500 m to the River
Sat. The eruption resulted ashfalls in 5 districts surround Merapi, i.e.:
Dukun, Srumbung, Salam, Ngluwar and Muntilan with the radius about 15-20
km. An increasing activity began on Saturday night (27 January at 00.00
local time), marked with continuous pyroclastic flow and molten lava
avalanche as long as 2 hours respectively. Eruption thick ash with strong
sulphurous smelt thundering about 2000 m above the summit. Until the
report, Merapi activity is ongoing and higher.
Merapi volcano is in level 3.
Topic 2 of 99 [Geo]: Vulcanism
Response 354 of 997: Neil Hodgins (ThinkingManNeil) * Wed, Feb 7, 2001 (09:53) * 37 lines
Unusual Thermal Activity at Rotorua, NZ
January 26 eruption at Kuirau Park, Rotorua
Notes and comments from BJ Scott. (images below)
These notes and comments are based on a visit on Friday evening, and again on Monday.
On Friday 26 January about 3.30 to 3.40 PM NZDT, a muddy hot pool 2.5-3m diameter (Spring 721) burst into eruption, generating the largest hydrothermal eruption in Kuirau Park since 1966. The eruption of blocks and mud was to about 100 metres height and produced a thick carpet of blocks and mud to the east, extending over 120m from the vent. The eruption was very directional. Very little ejecta is distributed to the west (may be less than 30m from the vent). Blocks up to about 1m diameter were projected over 50m from vent, while blocks around 0.1m or less diameter landed over 100m away. The crater formed is about 10-12m in diameter.
It was possible to recognise 4 eruption deposits on Friday evening, and this may give some insight into the eruption. These are;
1) A ballistic block bed, the most widely distributed unit. It would appear that this unit is almost entirely formed from Oranui Formation.
2) A basal dark grey mud deposit directed to the east, ranging from about 400mm thick to a trace of only mm at Ranolf Street.
3) An upper, smaller and slightly lighter grey muds deposit. This was also distributed to the east, overlying the basal darker mud. It was smaller in distribution and the dispersal access was a little more to the SE. Thickness appeared to be about 100-150mm at it’s thickest.
4) A dark grey, very liquid hydrothermal mud distributed to the west, onto the adjacent road. This appears to be the contents of Spring 721.
The ballistic blocks appear to be present through almost all of the deposit. That is there are blocks that are clearly on top of all the mud’s, while other blocks are coated by mud with shelter zones on their leeward sides. Based on first impressions the dark grey liquid mud’s where erupted first, to the west. Then the main phase of the eruption commenced, ejecting mud’s and ballistic blocks to the east, this was followed by a smaller mud rich phase (no relationship with ballistics was ascertained), which was followed by a distinct ballistic shower, numerous cm sized blocks are impacted into all the mud’s. The ballistics extend well beyond the mud’s to the NE and its is not clear from first impressions the exact relationship to the mud’s.
Fallout of the mud layers has loaded all the trees and shrubs within the ejecta apron bending and braking many.
Images of the eruption:
Vegetation Damage
Geologist examining explosion crater
Eruption deposit of mud and blocks
Geologist examining block ejecta
Thermal Spring 721--site of the eruption
Topic 2 of 99 [Geo]: Vulcanism
Response 355 of 997: Marcia (MarciaH) * Wed, Feb 7, 2001 (19:55) * 1 lines
Oh Neil - such amazing images. Mahalo Nui Loa!!! More than ever I am content not to live on the Pacific Ring of Fire. *Hugs*
Topic 2 of 99 [Geo]: Vulcanism
Response 356 of 997: Marcia (MarciaH) * Wed, Feb 7, 2001 (20:41) * 22 lines
Re: The recent India Earthquake: (thanks Ian!)
from: Noerjadi, Andrea
Sent: 2/8/01 5:02 AM
Subject: Click and Donate for the EarthQuake Relief
There is a site called http://www.causeanaffect.org/ which is paid for by corporate sponsors. Every click on its "Save a life" button will
result in donation of food packets for the victims. It will not cost anything to the people clicking on the site, because corporations are paying for the donations. One click per day is counted for donation.
I would appreciate it if you pass it along to the people in your address book.
Regards-
fr
Yahoo! Groups Sponsor
www.
[earthquake] posts replies to all list recipients. earthquake@yahoogroups.com
Topic 2 of 99 [Geo]: Vulcanism
Response 357 of 997: Marcia (MarciaH) * Wed, Feb 14, 2001 (23:18) * 401 lines
*******************************************
GVP/USGS Weekly Volcanic Activity Report
7-13 February 2001
*******************************************
GVP/USGS Weekly Volcanic Activity Report
7-13 February 2001
NEW! World Map Showing Volcanoes Discussed This Week
New Activity/Unrest: | Ijen, Indonesia | Inielika, Indonesia | Kelut,
Indonesia | Lokon-Empung, Indonesia | Mayon, Philippines | Merapi,
Indonesia |
Ongoing Activity: | Guagua Pichincha, Ecuador | Karangetang, Indonesia |
Kilauea, USA | Popocatépetl, México | Shiveluch, Kamchatka | Soufrière
Hills, Montserrat |
New Activity
IJEN eastern Java, Indonesia 8.058°S, 114.242°E; summit elev. 2,386 m
During 30 January to 5 February, seismic activity increased at Ijen
volcano. This increase was marked by a large number of shallow volcanic
earthquakes (75). In addition, 2 small explosion events, 6 tectonic events,
and 2 tremor earthquakes occurred. The volcano is at Alert Level 2 (on a
scale of 1-4).
Background. The Ijen volcano complex consists of a group of small
stratovolcanoes constructed within the large 20-km-wide Ijen (Kendeng)
caldera. The N caldera wall forms a prominent arcuate ridge, but elsewhere
the caldera rim is buried by post-caldera volcanoes, including Gunung
Merapi stratovolcano, which forms the 2,799 m high point of the Ijen
complex. Immediately W of Gunung Merapi is the renowned historically
active Kawah Ijen volcano, which contains a nearly 1-km-wide,
turquoise-colored, acid crater lake. The picturesque lake is the site of a
labor-intensive sulfur mining operation, in which sulfur-laden baskets are
hand-carried from the crater floor. A half dozen small-to-moderate
phreatic eruptions have taken place from Kawah Ijen during the 20th century.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
More Ijen Reports <
http://www.volcano.si.edu/gvp/volcano/region06/java/ijen/var.htm> from the
monthly Bulletin of the Global Volcanism Network
INIELIKA central Flores, Indonesia 8.73°S, 120.98°E; summit elev. 1,559 m
During 6-11 February, Inielika volcano remained active and the VSI reported
no significant change in volcanic activity. An ash plume was observed
rising 25-500 m above the volcano and there was a slight increase in the
number of deep volcanic earthquakes in comparison to the previous week. The
Alert Level at the volcano was reduced from 3 to 2 (on a scale of 1-4).
Background. Inielika is a broad, low volcano in central Flores Island that
was constructed within the Lobobutu caldera.The complex summit of the
volcano contains ten craters, some of which are lake filled, in a 5-sq-km
area. The largest of these craters, Wolo Runu and Wolo Lega North, are 750
m wide. The first historical eruption of Inielika, a phreatic explosion
that formed a new crater, did not occur until 1905, and was the volcano's
only eruption during the 20th century.
Source: Volcanological Survey of Indonesia,
http://www.vsi.dpe.go.id/news/index.html
No past reports
KELUT Java, Indonesia 7.93°S, 112.31°E; summit elev. 1,731 m
VSI scientists found that the temperature of Kelut’s crater lake had
increased and its pH dropped as follows. During 29 January to 7 February
the lake’s temperature ranged from 50.1 °C to 51 °C, compared with 47.5 °C
on 18 January and 38.5 °C on 8 January. On 7 February the pH of the water
was 5, compared with measurements of 6.3 in January 2001 and 6.9 in
November 2000. The volcano remained at Alert Level 2 (ranging from 1-4).
Background. The relatively inconspicuous 1,731-m-high Kelut stratovolcano
contains a summit crater lake that has been the source of some of
Indonesia's most deadly eruptions. A cluster of summit lava domes cut by
numerous craters has given the summit a very irregular profile. More than
30 eruptions have been recorded from Gunung Kelut since 1000 AD. The
ejection of water from the crater lake during Kelut's typically short, but
violent eruptions has created pyroclastic flows and lahars that have caused
widespread fatalities and destruction. After more than 5,000 people were
killed during the 1919 eruption, an ambitious engineering project sought to
drain the crater lake. This initial effort lowered the lake by more than 50
m, but the 1951 eruption deepened the crater by 70 m, leaving 50 million
cubic meters of water after repair of the damaged drainage tunnels. After
more than 200 people were killed in the 1966 eruption, a new deeper tunnel
was constructed, lowering the lake's volume to only about 1 million cubic
meters prior to the 1990 eruption.
Source: Volcanological Survey of Indonesia,
http://www.vsi.dpe.go.id/news/index.html
Kelut Reports
from
the monthly Bulletin of the Global Volcanism Network
LOKON-EMPUNG northern Sulawesi, Indonesia 1.36°N, 124.79°E; summit elev.
1,580 m
After explosions occurred on 28 January, volcanic activity decreased.
During 30 January to 5 February an ash plume was observed rising 200-350 m
above the volcano. The seismograph on the volcano broke on 30 January. The
volcano remained at Alert Level 3 (on a scale of 1-4).
Background. The twin volcanoes Lokon and Empung, rising about 800 m above
the plain of Tondano, are among the most active volcanoes of Sulawesi.
Lokon, the higher of the two peaks (whose summits are only 2.2 km apart)
has a flat, craterless top. The morphologically younger Empung volcano has
a 400-m-wide, 150-m-deep crater that erupted last in the 18th century, but
all subsequent eruptions have originated from Tompaluan, a 150 x 250 m wide
double crater situated in the saddle between the two peaks. Historical
eruptions have primarily produced small-to-moderate ash plumes that have
occasionally damaged croplands and houses, but lava-dome growth and
pyroclastic flows have also occurred.
Source: Volcanological Survey of Indonesia,
http://www.vsi.dpe.go.id/news/index.html
Lokon-Empung Reports
from the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
The PHIVOLCS reported that volcanic activity remained high at Mayon.
Abundant low-frequency volcanic earthquakes associated with dome growth
took place on 7, 8, 9, 11, and 12 February and consisted of 29, 30, 29, 45,
and 30 events, respectively. Also on 12 February seismometers detected 2
rockfalls. The crater emitted voluminous steam and sulfur, with a maximum
of ~7,100 metric tons of SO2 detected on 12 February. Tiltmeters on the
volcano’s N flank continued to detect slight edifice inflation. On 11
February, PHIVOLCS reported that most of the springs in the E and S
quadrants of the volcano showed a decrease in discharge, despite increasing
rainfall. Inclement weather prevented observations of the volcano. Mayon
remained at Alert Level 3 (on a scale of 0-5).
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon's most violent eruption, in 1814,
killed more than 1,200 people and buried an entire town in volcanic mud.
Eruptions that began in February 2000 led PHIVOLCS to recommend on 23
February the evacuation of people within 7 km of the summit in the SE and
within 6 km for the rest of the volcano.
Sources: Philippine Institute of Volcanology and Seismology,
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
Mayon Reports
from
the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m;
All times are local (= GMT + 7 hours)
Intense and dangerous volcanic activity continued at Merapi with hot lava
avalanches, near-continuous pyroclastic flows, and an eruption on 10
February that deposited ash on many cities out to 60 km E of the volcano.
During 30 January to 5 February, continuous hot lava avalanches and
pyroclastic flows traveled down the SW flank of the volcano along the Sat,
Senowo, and Bebeng rivers to a maximum runout distance of ~4.5 km. Lava
avalanches also traveled down the Lamat River, a drainage that avalanches
had not previously traveled down during the current period of volcanic
activity. Approximately 25 pyroclastic flows occurred daily. Ash associated
with the pyroclastic flows fell around Merapi. During 0430 to 0630 on 3
February heavy rain mixed with ash and produced minor lahars. On 6 February
the dome was reported as being 1 million cubic meters in volume and growing
at 45 cubic meters per day.
Pyroclastic-flow activity began at 2100 on 9 February and lasted up to 1
hour. At 0200 on 10 February, a medium-sized pyroclastic flow lasted for
~30 minutes. At 0330 the same day “lava dome 1998,” which was under the new
lava dome (“lava dome 2001”), partially collapsed. The collapse triggered
a large and continuous pyroclastic flow that lasted as long as 2.5 hours.
The pyroclastic flow traveled up to 7 km SW of the summit towards the Sat
River, and 4.5 WSW to the Lamat River. The resultant ash cloud rose up to
5-8 km above the summit, spread ~60 km towards the E, and deposited ash on
the towns of Klaten, Solo, Sukoharjo, and Boyolali. The greatest ash
thickness was ~1 cm, reported within a 5 km radius around the volcano. At
0530 the Alert Level at the volcano was raised from 3 to 4, the highest
level. News articles reported that ~12,000 residents near the volcano were
evacuated on 10 February, though many people returned to their property the
next day despite the evacuation order. By 11 February, lava dome 2001 was
estimated to be 1.4 million cubic meters in volume and unstable, especially
after the 10 February collapse of “lava dome 1998.”
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Sources: Volcanological Survey of Indonesia,
http://www.vsi.dpe.go.id/news/index.html
Darwin VAAC, http://www.ssd.noaa.gov/VAAC/OTH/AU/messages.html
Australian Broadcasting Company
http://www.abc.net.au/news/newslink/weekly/newsnat-10feb2001-83.htm,
Associated Press
http://dailynews.yahoo.com/h/ap/20010211/wl/indonesia_volcano_4.html
Merapi Reports
from
the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
GUAGUA PICHINCHA north-central Ecuador 0.17°S, 78.60°W; summit elev. 4,784 m
Lava dome growth continued at dome 9 at a rate similar to that of previous
weeks. Rockfalls were observed travelling to the SW towards Cristal River.
The volcano remained at Alert Level Yellow
.
Background. Guagua Pichincha rises immediately W of Quito, Ecuador’s
capital city. The broad volcanic massif is cut by a large horseshoe-shaped
summit caldera, ~6 km in diameter and 600 m deep, that was breached to the
W during a slope failure ~50,000 years ago. Subsequent late-Pleistocene
and Holocene eruptions from the central vent consisted of explosive
activity with pyroclastic flows accompanied by periodic lava dome growth
and destruction. A major eruption in 1660 deposited 30 cm of ash in Quito,
but most of the many eruptions since the Spanish colonial era have been
minor. The latest eruptive period began with phreatic explosions in 1998.
Magmatic eruptions first occurred in October 1999, and intermittent
eruptions of varying scale since then have blanketed Quito and surrounding
towns with ash.
Source: Instituto Geofísico http://www.epn.edu.ec/~igeo/index.html
Guagua Pichincha Reports
http://www.volcano.si.edu/gvp/volcano/region15/ecuador/guagua/var.htm from
the Bulletin of the Global Volcanism Network
KARANGETANG [API SIAU] Siau island, Indonesia 2.78°N, 125.48°E; summit
elev. 1,784 m
The VSI reported that since the 28 January eruption there has been no
significant change in activity observed at Karangetang. Seismicity remained
dominated by multi-phase earthquakes. The volcano remained at Alert Level 2
(on a scale of 1-4).
Background. Karangetang (also known as Api Siau) lies at the northern end
of the island of Siau, N of Sulawesi, and contains five summit craters
strung along a N-S line. One of Indonesia's most active volcanoes,
Karangetang has had more than 40 recorded eruptions since 1675.
Twentieth-century eruptions have included frequent explosions, sometimes
accompanied by pyroclastic flows and lahars.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Karangetang reports
from
the Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Surface flows continued to travel down the Pulama pali, with no lava
entering the sea. A tiltmeter near the HVO showed a small (about 0.4
microradian) deflation shortly before 1230 on 10 February. After 10
February, tiltmeters in the summit area and along the E rift zone showed
flat signals. Volcanic tremor near Pu`u `O`o and in Kilauea`s caldera was
at low-to-moderate levels.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes.
Historically its eruptions originate primarily from the summit caldera or
along one of the lengthy E and SW rift zones that extend from the caldera
to the sea. The latest Kilauea eruption began in January 1983 along the E
rift zone. The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and
55th eruptive episode. Since 1986, flows have traveled 11-12 km from the
vents to the sea, paving about 80 km2 of land on the S flank of Kilauea and
building 205 hectares of new land. Intensive monitoring and field research
by staff of the Hawaiian Volcano Observatory, established in 1912, make
Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= GMT 6 hours)
The Washington VAAC reported several small ash-bearing eruptions during the
week. At 1921 on 8 February an eruption produced a small ash cloud that
rose up to ~7.6 km a.s.l. and blew to the NE. At 1400 on 9 February an
eruption produced an ash cloud that rose up to ~6.7 km. A small ash plume
produced from emissions that occurred at 1338 and 1348 on 11 February was
visible in GOES-8 imagery. The ash plume rose up to ~7.9 km a.s.l. and blew
to the S.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava
domes have incrementally been constructed within the summit crater and
destroyed by explosive eruptions. Intermittent small-to-moderate
gas-and-ash eruptions have continued, occasionally producing ashfall in
neighboring towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Sources: Centro Nacionale de Prevencion de Desastres,
http://www.cenapred.unam.mx/boletines.html
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m; All times are local (= GMT + 12 hours)
The KVERT reported that during most of the week seismicity was at
background levels. At 1100 on 2 February a powerful gas-and-ash eruption
produced a plume that rose 800 m above the volcano and spread ~3 km towards
the W. The same day, observations from Klyuchi town revealed that at 1804 a
short-lived eruption produced an ash plume that rose up to ~5.3 km a.s.l.
The event was accompanied by a 2-minute-long shallow seismic signal that
was detected more than 110 km from the volcano. Afterwards, during 1807 to
1824 strong volcanic tremor was registered. The Concern Color
remained at Yellow.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large breached caldera formed by collapse of the
massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
SOUFRIERE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,052 m
The MVO reported that during 2 to 9 February activity at the Soufrière
Hills volcano was slightly higher than during the previous week as lava
dome growth continued. Seismic activity remained similar to the previous
week, although it increased towards the end of the report week. Rockfall
activity was low during the beginning of the week, but significantly
increased beginning on 6 February; only 9 rockfalls were recorded on 5
February, while 70 were recorded on 6 February. Brief observations revealed
that volcanic activity remained concentrated on the E side of the lava dome
and that two large near-vertical spines stood on the dome’s summit. By 8
February new pyroclastic-flow deposits were emplaced at the head of Tuitt’s
Ghaut ~300 m to the N of the dome. The Washington VAAC reported that
throughout the week low-level (up to
~2.1 km a.s.l.) ash clouds, presumably produced by rockfalls, and periodic
hot-spot activity were visible on GOES-8 imagery.
Background. The complex andesitic Soufriere Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that initially
forced evacuation of the southern half of the island and then destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvomrat.com/
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufriere Hills Reports
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 358 of 997: Marcia (MarciaH) * Wed, Feb 14, 2001 (23:19) * 2 lines
Etna is active if anyone wants to watch:
http://web.poseidon.nti.it/Sorvis/vulcano.asp?Vulcano=Etna&Refresh=30
Topic 2 of 99 [Geo]: Vulcanism
Response 359 of 997: Marcia (MarciaH) * Fri, Feb 16, 2001 (15:47) * 44 lines
*******************
Miyakejima, Japan
*******************
Dr. S. Nakada's (University of Tokyo) web page update on Japan's Miyakejima
shows that although eruptive activity probably ended in October 2000, and
subsidence deformation is waning, the extraordinarily high SO2 emission
rates continue at 20, - 50,000 metric tons/day. Low seismic levels since
September. Increasing temperatures in the active crater reached 4000C in
late December with slight incandescence, but the incandescence has since
disappeared.
From: http://hakone.eri.u-tokyo.ac.jp/vrc/erup/miyake.html
National Coordination of Volcanic Eruption Prediction, chaired by Prof.
Yoshiaki Ida (Univ. of Tokyo) issued the comments on the Miyakejima
activity on February 5, 2001, as follows.
Huge amount of volcanic gas has been emitted from the summit crater at
Miyakejima.
No typical eruptions had taken places except for the emission of volcanic
gas since last October. Ash fall was reported in only the places nearby
crater. The temperature of the active crater had increased by December, 400
degree C in late-December, associated with slight incandescence in nights,
the latter which disappeared in late-January.
Ground deformation implying shrinkage of Miyakejima, which began in last
July, had declined, though it has still continued in the smallest level.
Seismic activity had been low in level since last September, although
low-frequency earthquakes occurred in the shallow part in late-January.
The height of smokes emitted from the summit crater ranged from several
hundreds to two thousand meters above the crater. The amount of SO2 emitted
had been maintained in a range from about 20 to 50 kiloton a day. High
abundance of SO2 often had been observed even at the volcano flanks
depending on weather condition. Most of SO2 is considered to result from
degassing from magma. At the present, there is no sign indicating the
decrease in abundance of SO2 emitted.
As the activity emitting SO2 is considered to still continue at Miyakejima,
should pay attention to volcanic gas. Also attention to mud flows is needed
when rains.
Topic 2 of 99 [Geo]: Vulcanism
Response 360 of 997: Marcia (MarciaH) * Tue, Feb 20, 2001 (14:43) * 14 lines
Erupting Alaska Volcano Creates Ash Plume
ANCHORAGE, Alaska (Reuters) - A volcano on an uninhabited island in
Alaska's Aleutian chain erupted, sending a plume of ash as high as
35,000 feet, the Alaska Volcano Observatory said.
Cleveland Volcano, a 5,674-foot peak on remote Chuginadak Island,
erupted at about 6 a.m. Alaska time (noon EST), the observatory said.
A few hours later Monday, a light dusting of ash was reported in the
nearest community, Nilkoski, an Aleut village of about
30 people that is 45 miles east of the Cleveland Volcano, the
observatory said.
Eleven eruptions of Cleveland Volcano have been reported since 1893,
the observatory said.
Chuginadak Island is about 950 miles southwest of Anchorage.
Topic 2 of 99 [Geo]: Vulcanism
Response 361 of 997: Marcia (MarciaH) * Tue, Feb 20, 2001 (18:38) * 80 lines
*******************************************************
AVO Information Release: Cleveland eruption 02-19-2001
*******************************************************
From: avo-sci@usgs.gov
ALASKA VOLCANO OBSERVATORY
Monday, February 19, 2001 1600 AST (0100 UTC)
CLEVELAND VOLCANO (CAVW #1101-24)
VOLCANIC ACTIVITY REPORT #02 (abridged)
52°49'N 169°57'W
Summit Elevation 5,674 ft (1,730 m)
Cleveland volcano in the central Aleutian Islands erupted explosively this
morning at approximately 0600 AST (1500 UTC). As of 1600 AST (0100 UTC
February 20) satellite images indicate the main part of the ash cloud lies
in a region bounded by 53o - 55oN, 168o? 171oW. The most recent Volcanic
Ash Advisory Statement (issued 2300 UTC) reports that the ash cloud is
moving eastwards at approximately 30 knots. Pilot reports from 1310 AST
(2210 UTC) indicate ash cloud tops at 35,000 feet ASL. Subsequent pilot
reports and satellite data indicate diminishing intensity of the ash plume
emanating from the volcano. Observers in Nikolski (45 miles east of Mt.
Cleveland) reported light ash fall starting at 1200 AST (2100 UTC),
continuing through to the present.
-------------
ALASKA VOLCANO OBSERVATORY
Monday, February 19, 2001 2130 AST (0630 UTC)
CLEVELAND VOLCANO (CAVW #1101-24)
VOLCANIC ACTIVITY REPORT #03
52°49'N 169°57'W
Summit Elevation 5,674 ft (1,730 m)
Cleveland volcano in the central Aleutian Islands erupted explosively this
morning at approximately 0600 AST (1500 UTC). A Volcanic Ash Advisory
Statement (issued 2300 UTC) reported the ash cloud moving eastwards at
approximately 30 knots. Pilot reports from 1310 AST (2210 UTC) indicate ash
cloud tops at 35,000 feet ASL. Subsequent pilot reports and satellite data
indicate first a diminishing intensity of the ash plume emanating from the
volcano and by late afternoon an ending of explosive activity. Observers in
Nikolski (45 miles east of Mt. Cleveland) reported light ash fall starting
at 1200 AST (2100 UTC) and ending about 1600 AST (0100 UTC). The ash and
steam cloud, which extended in a northerly direction for at least 75 miles,
has drifted eastward towards Dutch Harbor, Akutan, and beyond by 1900 AST
(0400 UTC). Satellite imagery continues to show a large thermal anomaly at
the volcano and further explosive eruptions could occur with very little
warning.
Mt. Cleveland forms the western half of Chuginadak Island, a remote and
uninhabited island in the east central Aleutians. It is located about 40
km (25 mi) west of Umnak Island and about 75 km (45 mi) west of the
community of Nikolski. A distinctively symmetrical stratovolcano,
Cleveland has erupted 11 times since 1893. On May 25, 1994 sent a
short-lived ash plume to about 10.5 km (35,000 ft) altitude. Ash fall from
this eruption impacted the north and east flanks of the volcano, and small
debris flows may have formed on the southwest flank. On October 20, 1994,
AVO identified another possible ash plume on satellite imagery; however, no
eruption was confirmed.
Recent eruptions from Mt. Cleveland have been characterized by short-lived
explosive bursts of ash, at times accompanied by lava fountaining, lava
flows, and debris flows down the flanks. Cleveland is not seismically
monitored, therefore we do not assign it a level of concern color code.
AVO will continue to monitor the situation closely and will issue further
updates as information becomes available.
abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
volcano information on the internet: http://www.avo.alaska.edu
Topic 2 of 99 [Geo]: Vulcanism
Response 362 of 997: Marcia (MarciaH) * Tue, Feb 20, 2001 (19:08) * 56 lines
*************************************
MVO weekly report, 16 February 2001
*************************************
From: Dr Gill Norton
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 9 February 2001 to midday, 16 February 2001
Activity at the Soufrière Hills Volcano fluctuated markedly this week, as
growth of the lava dome continued.
The level of seismic activity varied considerably through the week, with a
pronounced peak in activity over the weekend. Since that time, the rockfall
activity has gradually decreased. The broadband seismic network recorded a
total of 500 rockfall signals, 100 long period rockfall signals, 1
volcano-tectonic, 2 hybrid, and 15 long period earthquakes for the reporting
period. The energy of the rockfalls and long period rockfalls peaked early
on the morning of 11 February.
Visibility of the volcano has been reasonable this week, with some excellent
views on 13 and 14 February. The two large spines observed last week had
collapsed, and a large lobe had formed on the eastern face of the dome above
Tar River. New pyroclastic flow deposits had formed down Tar River, although
they had not reached as far as the old coastline. Some small-volume deposits
were observed down White River to the south and in Tuitt’s Ghaut to the
northeast.
Sulphur dioxide gas measurements were made with the correlation spectrometer
this week. On 9 and 15 February, measurements from the helicopter gave
average fluxes of 670 and 420 tonnes per day respectively. Static
measurements on 9 and 14 February gave average fluxes of 220 and 80 tonnes
per day. Static measurements are consistently lower than helicopter
traverses.
Rockfall and pyroclastic flow activity is likely to continue whilst the dome
grows, producing ash clouds which may blow over inhabited areas. Ash masks
should be worn in ashy conditions or when ash is disturbed.
Residents of Montserrat and visitors to the island are advised to tune in to
ZJB Radio for up-to-date information on the status of the volcano. Elevated
levels of pyroclastic flow activity may develop very rapidly and could
affect any valleys around the volcano. In addition to the risk from
pyroclastic flows, the Belham valley should also be avoided during and after
periods of heavy rain. Everyone is reminded that access to Plymouth, Bramble
airport and beyond is prohibited. There is a maritime exclusion zone around
the southern part of the island that extends two miles beyond the coastline
from Trant’s Bay in the east to Garibaldi Hill on the west coast. The
daytime entry zone remains closed.
12 noon, Friday, 16 February 2001
Check out the MVO’s web site at www.mvomrat.com for recent pictures of the
dome.
Topic 2 of 99 [Geo]: Vulcanism
Response 363 of 997: Marcia (MarciaH) * Tue, Feb 27, 2001 (13:24) * 0 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 364 of 997: Marcia (MarciaH) * Wed, Mar 7, 2001 (20:49) * 16 lines
GVP/USGS Weekly Volcanic Activity Report
28 February- 6 March 2001
New Activity/Unrest: | Cleveland, USA | Kliuchevskoi, Kamchatka | Lokon-Empung, Indonesia | Mayon, Philippines | Merapi, Indonesia |
Ongoing Activity: | Etna, Italy | Kilauea, USA | Ijen, Indonesia | Popocatépetl, México | Semeru, Indonesia | Shiveluch, Kamchatka | Soufrière Hills, Montserrat |
New Activity
CLEVELAND Aleutian Islands, USA 52.82°N, 169.95°W; summit elev. 1,730 m
The AVO reported that no further eruptive activity was observed or detected at Cleveland since the 19 February eruption. During 19 February to 2 March, GOES-10 imagery showed a weak thermal anomaly that was probably related to hot material deposited on the flanks of the volcano on the 19th. Photographs taken a few days after the eruption showed significant accumulation of spatter and lava blocks high on the steep flanks of the volcano; occasional avalanching of this debris may produce small, localized ash plumes.
Background. The symmetrical Mount Cleveland stratovolcano is situated at the western end of the uninhabited dumbbell-shaped Chuginadak Island in the east-central Aleutians. The 1,730-m-high stratovolcano is the highest of the Islands of Four Mountains volcanoes and is one of the most active in the Aleutians. Numerous large lava flows descend its flanks. It is possible that some 18th to 19th century eruptions attributed to Carlisle volcano, located across the Carlisle Pass Strait to the NW, should be ascribed to Cleveland. In 1944 Cleveland produced the only known fatality from an Aleutian eruption. Recent eruptions from Mt. Cleveland have been characterized by short-lived explosive ash emissions, at times accompanied by lava fountaining and lava flows down the flanks.
Source: Alaska Volcano Observatory, http://www.avo.alaska.edu/avo4/updates/updates.htm
http://www.avo.alaska.edu/avo4/updates/updates.htm
Cleveland Reports http://www.volcano.si.edu/gvp/volcano/region11/aleutian/cleve/var.htm
http://www.volcano.si.edu/gvp/volcano/region11/aleutian/cleve/var.htm
Topic 2 of 99 [Geo]: Vulcanism
Response 365 of 997: Marcia (MarciaH) * Sat, Mar 10, 2001 (15:43) * 72 lines
*************************************
Kamchatkan Volcanic Activity, 9 March, 2001
*************************************
INFORMATION RELEASE 09-02
Friday, March 9, 2001, 13:30 KST (2250 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Standard Time, 21 hours ahead of Anchorage.
KLYUCHEVSKAYA GROUP OF VOLCANOES
KLYUCHEVSKOY VOLCANO; 56o03'N, 160o39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
During the past week (March 2-8), seismic activity was near background
levels. Weak interrupted spasmodic tremor was registered. On March 3 and
5-7, a gas and steam plume rose 100-200 m above the volcano and extended 5
km to the southeast on March 7. On March 4, a gas and steam plume rose
600-1000 m above the volcano and extended more than 10 km to the northeast.
On other days, the volcano was obscured by clouds.
BEZYMIANNY VOLCANO; 55o58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity was registered under the volcano during the week. On March
2-3 and 5-7, a gas and steam plume rose 50-400 m above the volcano and
extended up to 15 km to the southeast. On other days, the volcano was
obscured by clouds.
SHEVELUCH VOLCANO; 56o38'N, 161o19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
Seismicity mainly at background levels. On March 2-6, several series of
shallow earthquakes were registered. Following them, in certain cases, weak
spasmodic volcanic tremor was registered. Possibly these bursts of activity
corresponded to weak ash-gas explosions to a height of 2000-3000 m above
the crater. According to visual data and satellite images AVO, on March
2-6, a gas and steam plume rose 300-800 m above the volcano and extended
50 km to the east on March 3-4. At 15:45 KST, on March 7, seismic data
indicated a short-lived gas-ash explosions probably occurred as a series of
shallow earthquakes and high-frequency tremor were registered during 15
minutes. According to visual reports from Klyuchi town, at 16:00 KST , an
ash-gas plume rose 1500 m above the dome and extended km to the
northwest. According to information from Elizovo airport, at 16:20 KST
pilots registered (flight # 74052,elevation of flight 8,100 m) an ash plume
of a height about 10 km above Sheveluch volcano moving 30 km to the
northeast. Satellite images (AVO) from 17:15 KST show two plumes of the
cloud. One extended to the east from the volcano, and was a low altitude
mostly steam plume. The other extended to the north, and had a signal that
indicates volcanic ash. The plume extended for 50 km to the north at a
height of 7-8 km ASL. On March 8, the volcano was obscured by clouds. Short
series of shallow earthquakes and spasmodic volcanic tremor continued to be
recorded.
KARYMSKY VOLCANO; 54o03'N, 159o27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was near background levels. During the week a few short
series of small shallow earthquakes and one episode of weak high-frequency
spasmodic tremor were registered
AVACHINSKAYA GROUP OF VOLCANOES; 53o15'N, 158o51'E;
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
MUTNOVSKAYA GROUP OF VOLCANOES:
GORELY VOLCANO; 52o33'N, 158o02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o27'N, 158o12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
During the past week seismic activity was at background levels. On March
2-5 and 7-8, Gorely volcano was quiet. On March 2-5 and 7-8, a gas - steam
plume rose 200-500 m above Mutnovsky volcano. On March 6, both volcanoes
were obscured by clouds.
Topic 2 of 99 [Geo]: Vulcanism
Response 366 of 997: Marcia (MarciaH) * Sat, Mar 10, 2001 (15:43) * 39 lines
***********************************************
AVO Weekly Update, 9 March, 2001
***********************************************
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, March 9, 2001 12:00 PM AST (2100 UTC)
CLEVELAND VOLCANO (CAVW #1101-24)
52°49'N 169°57'W Summit Elevation 5,674 ft (1,730 m)
No further eruptive activity has been reported or detected at Cleveland
volcano. As such, AVO will stop detailing activity at Cleveland in these
updates until new activity is detected or reported.
OTHER ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
all at or near normal levels of background seismicity. AVO did not detect
ash plumes or significant elevated surface temperatures in the vicinity of
any volcano.
abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
volcano information on the internet: http://www.avo.alaska.edu
Topic 2 of 99 [Geo]: Vulcanism
Response 367 of 997: Marcia (MarciaH) * Sat, Mar 10, 2001 (15:50) * 12 lines
******************************
Lava Tube Formation Request
******************************
I'm in search of an animation depicting lava tube formation. Does
anyone know of such a thing and where I might find it? If so, please
reply to Ralph Hitz. Thank you. (Sorry for the repeat message for those individuals
that I've already contacted about this.)
Ralph Hitz [rhitz@tcc.tacoma.ctc.edu]
Topic 2 of 99 [Geo]: Vulcanism
Response 368 of 997: Marcia (MarciaH) * Sat, Mar 10, 2001 (15:51) * 59 lines
******************************
MVO Weekly Report, 9 March 2001
******************************
From: Dr Gill Norton
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 2 March 2001 to midday, 9 March 2001
Activity at Soufrière Hills Volcano decreased this week with a return to
steady growth of the lava dome.
The broadband seismic network recorded a total of 629 rockfall signals, 22
long period rockfall signals, 45 long period earthquakes, 4 volcano-tectonic
and 280 hybrid earthquakes. The banded tremor recorded last week had died
away by early in the week. Almost all the hybrid earthquakes were associated
with this tremor activity. During the middle part of the week rockfall
activity, which had been low, returned to more usual levels. The volcano
seemed to have resumed steady dome growth by the end of the week.
Observations confirmed that the main growth area had switched to the south
of the dome with most rockfall activity concentrated in the upper reaches of
the White River valley. Light ashfall from the activity this week was blown
over the north of the island although, by the end of the week, the wind had
switched back to the more usual direction towards the west.
Sulphur dioxide gas measurements were made with the correlation spectrometer
this week. On 8 March measurements from the helicopter gave an average flux
of 240 tonnes per day. Static measurements on 2, 6, 7 and 8 March gave
average fluxes of 1230, 190, 100 and 370 tonnes per day respectively.
The final report from the scientific and hazards assessment of Soufrière
Hills Volcano in January 2001 was published today. Check out the MVO website
for a full copy of the report (www.mvomrat.com).
Rockfall and pyroclastic flow activity is likely to continue whilst the dome
grows, producing ash clouds which may blow over inhabited areas. Ash masks
should be worn in ashy conditions or when ash is disturbed.
Residents of Montserrat and visitors to the island are advised to tune in to
ZJB Radio for up-to-date information on the status of the volcano. Elevated
levels of pyroclastic flow activity may develop very rapidly and could
affect any valleys around the volcano. In addition to the risk from
pyroclastic flows, the Belham valley should also be avoided during and after
periods of heavy rain. Everyone is reminded that access to Plymouth, Bramble
airport and beyond is prohibited. There is a maritime exclusion zone around
the southern part of the island that extends two miles beyond the coastline
from Trant's Bay in the east to Garibaldi Hill on the west coast. The
daytime entry zone remains closed.
12 noon, Friday, 9 March 2001
Dr Gill Norton
Director
Montserrat Volcano Observatory
Mongo Hill
Montserrat
West Indies
Topic 2 of 99 [Geo]: Vulcanism
Response 369 of 997: Marcia (MarciaH) * Sat, Mar 10, 2001 (16:12) * 106 lines
**********************************
Bulletin of the Global Volcanism Network
Volume 26, Number 1, January 2001
From: Ed Venzke
**********************************
Merapi (Indonesia) Failure of 1998 lava dome on 10 February causes major eruption
Krakatau (Indonesia) Eruptive activity through late October 2000; infrasonic earthquakes detected
Peuet Sague (Indonesia) 1999 activity continues through 14 June; explosions in late December 2000
Karangetang (Indonesia) Explosions in late January 2001 eject ash and lava
Lokon-Empung (Indonesia) 28 January explosion sends ash and glowing ejecta skyward
Inielika (Indonesia) Explosive activity declines; new images of the summit area
Tengger Caldera (Indonesia) Minor explosions, ash emissions, and tremor through 8 January 2001
Aoba (Vanuatu) Sustained elevation of Lake Voui's temperature indicates increased heat transfer
Nyamuragira (Africa) Lava flows began erupting in early February; one injury reported
Guagua Pichincha (Ecuador) Year 2000 summary; geophysicist takes fatal fall in January 2001
Cleveland (Aleutian Islands) 19 February explosion sends ash up to 10 km
Obituary
Death of volcano seismologist Diego Viracucha at Guagua Pichincha
Rick Wunderman, Edward Venzke, Gari Mayberry, Luke Jensen, and David Charvonia
Merapi
central Java, Indonesia
07.54 S, 110.44 E; summit elev. 2,911 m
All times are local (= UTC + 7 hours)
Renewed unrest began on the night of 27 January with continuous pyroclastic flows and hot lava avalanches, which lasted up to two hours. Since mid-January a Level 3 hazard status has remained in effect for the volcano. The Volcanological Society of Indonesia (VSI) reported that on 28 January 2001 Merapi's "2001" lava dome (Bulletin v. 25, no. 12) partially collapsed resulting in pyroclastic flows and hot lava avalanches with recurrence intervals of ~2-5 minutes. Pyroclastic material flowed down to the Sat, Bebeng, and Senowo Rivers, to the SW, SW, and W of Merapi, respectively. Their maximum runout distance occurred in the Sat River drainage, where flows reached ~4.5 km from the source. A plume, thick with sulphurous ash, rose 2 km above the summit. The eruption generated ashfalls within a radius of 15-20 km; ash fell on the Dukun, Srumbung, Salam, Ngluwar, and Muntilan Districts surrounding Merapi.
VSI geophysicist Ratdomopurbo reported that the unstable lava dome was actively growing taller and larger; continued magma chamber injection had caused the pyroclastic flows and lava avalanches at the surface. Magma migration was indicated by increased deep volcanic (A-type) and shallow volcanic (B-type) earthquakes since August 2000. On 31 January pyroclastic flows occurred continuously, reaching up to ~3.5 km from the summit and flowing mainly into the Sat River, but also into the Senowo and Bebeng Rivers. At Babadan Observatory, located 4 km from the summit, a seismograph recorded earthquakes related to pyroclastic flows that exceeded the instrument's scale for up to 60 seconds during the interval of 1601-1822. Ashfall continued within 15 km of Merapi. A recent photograph showed a new active vent on Merapi's summit. VSI scientists engaged in Merapi research remained uncertain whether the vent in the photo had only emitted gases or had also emitted lava and tephra.
Pyroclastic flows and lava avalanches continued through 5 February (figures 1 and 2). Approximately 25 pyroclastic flows occurred daily and moved down the flanks to the Sat, Bebeng, and Senowo Rivers with a maximum runout distance of 4.5 km. Lava avalanches flowed down to the Lamat River, W of the volcano, in addition to the three above-mentioned rivers; lava avalanches reached a distance of 3.5 km from Merapi's summit, falling 1 km short of flows from the previous week. Ashfalls continued, and heavy rain on 3 February caused a minor lahar that initiated at 0430. Summarizing observations, Syamsul Rizal Wittiri stated that Merapi's lava dome continued to grow larger with the addition of ~45,000 cubic meters of material per day; lava dome volume as of 6 February was 1 million cubic meters. On 9 February at 2100 a continuous pyroclastic flow occurred for ~1 hour.
A major eruptive episode occurred on 10 February (figure 3). At 0200 purported magma migration toward the surface was associated with a medium-sized, 30-minute-long pyroclastic flow. At 0330 failure of the 1998 lava dome sent an ash cloud billowing 5 km above the summit and generated sizable pyroclastic flows that extended up to 7 km from Merapi in the direction of the Sat River and 4.5 km in the direction of the Lamat River. At 0530 Merapi's alert was raised from 3 to 4, the highest level, for the first time since July 1998 (Bulletin v. 23, no. 7). The ash plume from the eruption spread 60 km toward the E over the communities of Klaten, Solo, Sukoharjo, and Boyolali. Ashfall produced an ash layer with a maximum thickness of 1 cm at a 5 km radius from the volcano. Stations recorded high seismicity accompanying the eruption. Instrumentation detected decreasing magnetic intensity near the summit, indicating high heat and magma near the surface.
Syamsul Rizal Wittiri predicted that Merapi's activity will continue and potentially increase because the 2001 lava dome, which attained a volume of 1.4 million cubic meters, is unstable due to the collapse of the 1998 dome. Merapi's alert level remained at 4 as of 14 February.
Background. Merapi, one of Indonesia's most active volcanoes, dominates the landscape immediately N of the city of Yogyakarta in one of the world's most densely populated areas. The steep-sided modern edifice, its upper part unvegetated due to frequent eruptive activity, was constructed to the SW of an arcuate scarp cutting the eroded older Batulawang volcano. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated lands on the volcano's western-to-southern flanks and caused many fatalities during historical time.
Information Contacts: Dali Ahmad, Volcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (Email: dali@vsi.dpe.go.id; URL: http://www.vsi.dpe.go.id); Darwin Volcanic Ash Advisory Centre (VAAC), Bureau of Meteorology, Northern Territory Regional Office, PO Box 40050, Casuarina, NT 0811, Australia (URL: http://www.bom.gov.au/info/vaac/).
Krakatau
Sunda Strait
6.10 S, l05.42 E; summit elev. 813 m
Krakatau activity continued after the previous report (Bulletin v. 25, no. 5) through October 2000 although intensity decreased relative to the 29 May 2000 eruption. The volcano's hazard status, however, did not exceed 2 (on a scale of 1-4) within the report period. During 27 June-2 July explosions sent ash to heights up to 500 m, and booming sounds could be heard on three occasions. VSI reports resumed as of 25-30 July when seismographs recorded 1,961 explosion earthquakes, compared to 441 about a month earlier. An infrasonic sensor detected 37 events. A volcanic ash advisory was issued based on a pilot report of ash observed at an altitude of ~6,100 m. Satellite imagery did not detect a significant plume on this date, and no additional ash advisories were dispatched.
Activity remained similar through 15-21 August. Frequent booming was heard, and high numbers of explosion and infrasonic earthquakes were detected. A volcanic ash advisory was issued on 20 August although it indicated that plumes were sparse, did not reach high altitudes, and dissipated quickly. During 22 August-4 September a white, low-density plume rose 50 m above the summit. No visual observations could be made due to heavy fog, clouds, or smog masking the summit from view during 5 September-30 October, although seismicity indicated persistent activity. During 5-18 September, 3,220 explosions and 17 infrasonic events were recorded. Audible booming, however, ceased on 12 September, and activity decreased dramatically through the end of October. Deep volcanic (A-type) earthquakes stopped occurring as of 10 October, although a low number of small explosion earthquakes and tectonic earthquakes continued through 30 October. No further VSI reports were issued for Krakatau in 2000.
Background. Krakatau lies in the Sunda Strait between Java and Sumatra. Caldera collapse destroyed the ancestral Krakatau edifice, forming a 7-km-wide caldera. Remnants of this volcano formed Verlaten and Lang Islands; subsequently Rakata, Danan, and Perbuwatan volcanoes were formed, coalescing to create the Krakatau island extant prior to 1883. Caldera collapse during the catastrophic 1883 eruption destroyed Danan and Perbuwatan volcanoes, and left only a remnant of Rakata volcano. The post-collapse cone of Anak Krakatau (Child of Krakatau) grew within the 1883 caldera at a point between the former cones of Danan and Perbuwatan; Anak Krakatau has been the site of frequent eruptions since 1927.
Information Contacts: VSI; Darwin VAAC (see Merapi).
Peuet Sague
Sumatra, Indonesia
4.92 N, 96.33 E; summit elev. 2,780 m
All times are local (= UTC + 7 hours)
Peuet Sague's 1999 activity (Bulletin v. 24, no. 5) was reported to have continued, although at a decreased level, through 14 June 1999. A malfunctioning seismograph prevented instrumental monitoring in late May, but thin white gas-and-steam plumes that rose ~15 m were visible. During the first week in June plumes continued to rise to heights of 20 m. Rumbling was heard on 18 occasions, and plumes continued to rise through 14 June.
The VSI did not release further reports until renewed activity began at 0800 on 25 December 2000 with the first of three explosions. A second explosion occurred at 1310, and a third one followed at 1130 on 26 December. The explosions generated ash that spread over a relatively large area. Ashfall occurred on Geumpang, Lutung, Mane, and Bangke villages up to 20 km away. An observer from the village of Trans reported having seen glowing lava flows at night. Reported emissions ceased for the remainder of 2000, and the hazard status stayed at 2 (on a scale of 1-4).
Background. The Peuet Sague stratovolcano contains four summit peaks. The crater believed to be active resides SE of one of the peaks of the lava dome (Mount Tutung). This narrow crater has a diameter of about 70 m and a depth of 80 m. The last major eruption occurred in 1918-21 when ash was emitted, a lava dome was formed, and pyroclastic flows spilled into surrounding uninhabited forests. A 1975 team that reached the peak found no eruptive activity, but documented a lake (500 x 800 m) at the foot of Mount Tutung. Within Tutung's crater they found a small (40 x 75 m) blue lake surrounded by four solfataras. Scientists inspecting the summit area in 1984 found burned trees surrounding the main crater, likely due to a 1979 eruption. Local eyewitnesses and pilots reported ash columns above the summit in 1979, 1986, and 1991.
Information Contact: VSI (see Merapi).
Karangetang
Siau Island, Indonesia
2.47 N, 125.29 E; summit elev. 1,784 m
All times are local (= UTC + 8 hours)
Eruptive activity at Karangetang since the previous report (Bulletin v. 25, no. 12) continued through 5 February 2001. A minor explosion occurred at 2227 on 25 January and produced an ash-heavy plume that rose 700 m; ash fell into the sea W of the volcano. The eruption also featured a molten lava avalanche that flowed down to the Kelitu River with a maximum runout distance of ~1,250 m from the summit. At 2109 on 28 January a second, Strombolian-style explosion occurred that sent glowing ejecta 300 m above the crater; a black ash cloud rose 1 km and ashfall was observed on a nearby beach. The 28 January eruption also sent lava avalanches ~1,500 m down Karangetang's W flank. Seismicity for the period 23-29 January was dominated by multi-phase earthquakes.
During 30 January-5 February no significant visual activity was observed; multi-phase earthquakes outnumbered all others during the week. VSI maintained a hazard status of 2 (on a scale of 1-4) for Karangetang, and no further eruptive episodes were reported.
Background. Karangetang (also called Api Siau) lies at the northern end of the island of Siau, N of Sulawesi, and contains five summit craters strung along a N-S line. One of Indonesia's most active volcanoes, Karangetang has had more than 40 recorded eruptions since 1675. Twentieth-century eruptions have included frequent explosions, sometimes accompanied by pyroclastic flows and lahars.
Information Contact: VSI (see Merapi).
Lokon-Empung
northern Sulawesi, Indonesia
1.36 N, 124.79 E; summit elev. 1,580 m
All times are local (= UTC + 8 hours)
A white, low-density plume rose 50-200 m above Lokon's summit during 2-8 January 2001. Seismographs recorded a high number (~250) of both deep and shallow volcanic earthquakes during the week. The following week a plume continued to rise, and volcanic earthquakes decreased in number by about 90%. Discontinuous tremor with amplitudes of 0.5-6.0 mm was registered. During 16-22 January the plume rose up to 250 m in height. Volcanic earthquake activity again spiked, but reached only about half the quantity that had occurred during the first week of the month. Discontinuous tremor continued having amplitudes of 0.5-2.6 mm.
An explosion sent ash and glowing ejecta skyward from Lokon at 1920 on 28 January. Explosion earthquakes registered a maximum amplitude of 48 mm during a 175-second interval. Volcanic bombs were ejected from the crater and fell on Lokon's N slope. The ash cloud's specifics could not be measured due to rainy weather. Workers at the Kakaskasen observatory post detected an acrid sulphurous smell following the explosion. Observations the following day, 29 January, revealed a light-colored, high-density ash plume that rose ~300 m. The hazard status for Lokon was raised from 2 to 3 (on a scale of 1-4) following the explosion. Early February activity showed a decrease in unrest, although a high-density plume continued to rise up to 350 m, and small explosion earthquakes with amplitudes of 20-30 mm recurred.
Background. The twin volcanoes Lokon and Empung, rising about 800 m above the plain of Tondano, are among the most active volcanoes of Sulawesi. Lokon, the higher of the two peaks, whose summit is only 2.2 km from Empung's, has a flat, craterless top. The morphologically younger Empung volcano has a 400-m-wide, 150-m-deep crater that erupted last in the 18th century. All subsequent eruptions have originated from Tompaluan, a 150 x 250 m double crater situated in the saddle between the two peaks. A crater lake formed after the May 1969 eruption. Pyroclastic flows were reported in 1970.
Information Contact: VSI (see Merapi).
Inielika
Lesser Sunda Islands
8.73 S, 120.98 E; summit elev. 1,559 m
All times are local (= UTC + 8 hours)
The following report covers Inielika's activity during 23 January-5 February 2001. The VSI issued three photographs showing Inielika's summit area (figures 4-6). No explosions occurred during 23-29 January, unlike earlier in the month (Bulletin v. 25, no. 12). Instead, a white gas-and-steam plume rose 100-500 m above the summit. Volcanic earthquakes, tectonic earthquakes, and continuous tremor with amplitudes varying from 0.3 to 1.2 mm occurred.
Activity remained relatively similar during the following week of 30 January-5 February. A gas-and-steam plume rose 25-500 m above the summit. The number of deep volcanic (A-type) earthquakes increased with respect to the previous week, and tremor was no longer continuous. The VSI maintained Inielika's hazard status at Level 3 (on a scale of 1-4) as of 5 February.
Background. Inielika is a broad, low volcano on central Flores Island that was constructed within the Lobobutu caldera. The complex summit of the volcano contains ten craters, some of which are lake filled, in a 5-sq-km area. The largest of these, Wolo Runu and Wolo Lega North, are 750 m wide. The first historical eruption of Inielika, a phreatic explosion that formed a new 125-m-wide crater, did not occur until 1905, and was the volcano's only eruption during the 20th century.
Information Contact: VSI (see Merapi).
Tengger Caldera
Java, Indonesia
7.94 S, 112.95 E; summit elev. 2,329 m
Explosions from Bromo cone and unbroken tremor continued at Tengger Caldera since the previous report (Bulletin v. 25, no. 11). An average of 99 minor explosions daily during 19-25 December 2000 produced gray-brown ash that rose ~300-450 m above the cone's rim. The volcano's seismograph recorded 678 explosion earthquakes and tremor with amplitudes that ranged from 2 to 12 mm.
VSI reports resumed during 2-8 January 2001 when activity was purportedly lower. Small explosions sent gray-brown to dark ash 200 m above the crater, and about 29 events occurred per day. The seismograph registered 191 explosion earthquakes and continuous tremor with amplitudes of 2-10 mm. Tengger's hazard status remained at 2 (on a scale of 1-4), and no further VSI reports were issued. The Darwin Volcanic Ash Advisory Centre, however, issued an advisory to aviators on 15 January to warn them of an ash cloud up to an altitude of 3 km drifting toward the NE. The advisory also stated that ground-based observations indicated that irregular eruptions sent ash up to altitudes of 2,750 m, over 400 m above the Bromo cone. When the report was issued, ash was expected to spread E-NE at ~30 km/hour; heavy cloud-cover prevented the acquisition of satellite information concerning the eruption. No further ash advisories were released after 15 January.
Background. The 16-km-wide Tengger caldera is located at the northern end of a volcanic massif extending from Semeru volcano. The massive Tengger volcanic complex dates back to the early Pleistocene and consists of five overlapping stratovolcanoes, each truncated by a caldera. Lava domes, pyroclastic cones, and a maar occupy the flanks of the massif. The most recent of the Tengger calderas is the 9 x 10-km-wide Sand Sea caldera, which formed incrementally during the late Pleistocene and early Holocene. An overlapping cluster of post-caldera cones was constructed on the floor of the Sand Sea caldera within the past several thousand years. The youngest of these is Bromo, one of Java's most active and most frequently visited volcanoes. Bromo is a centrally located cone, with a 700-m-diameter crater; it has had more than 50 known eruptions since 1804.
Information Contacts: VSI; Darwin VAAC (see Merapi).
Aoba
Ambae Island, Vanuatu
15.38 S, 167.83 E; summit elev. 1,496 m
Voui crater lake's temperature and hydro-acoustic signals are measured continuously by an automated station that transmits in real time via satellite (Bulletin v. 23, no. 10). Recent measurements revealed heavy activity under the lake during March-June 2000 (Bulletin v. 25, no. 8), when the estimated 50 x 10^6 m^3 volume of water rapidly increased in temperature by more than 7 deg C (figure 7).
The increase was accompanied by acoustic signals covering a wide range of frequencies (figure 7, bottom). Those in the audible band ( 100 Hz) were thought to be associated with the emission of gas bubbles and an increase in submarine fumarolic activity. Those in the ultrasound band (30-190 kHz) could stem from fluids circulating within the hydrothermal zone beneath the lake (figure 8).
Background. Aoba, also called Lombenben, is an oval, basaltic shield volcano. Rising 3,900 m above its base to almost 1,500 m above sea level, Aoba has an estimated volume of 2,500 km^3, making it the largest of the volcanoes of the Hebrides Arc. It lies in front of the d'Entrecasteaux collision zone, at the boundary between the N and S Aoba basins. Two concentric summit calderas enclose a main central crater containing Lake Voui. Numerous secondary craters and cones lie along fractures leading to the edge of the island, where magma-seawater interactions in the past have produced several maars. The island is covered in a dense rainforest.
Information Contacts: Michel Lardy, Institut de Recherche pour le Developpement (IRD), Centre d"Ile de France 93143 Bondy Cedex, France (Email: lardy@bondy.ird.fr); Michel Halbwachs, Universite de Savoie, BP1104, F 73376 Le Bourget du Lac Cedex, France (Email: michel.halbwachs@univ-savoie.fr); Jeanne Tabbagh, Universite Pierre et Marie Curie, Department de geophysique appliquee, 75252 Paris Cedex O5, France (Email: tabbagh@ccr.jussieu.fr); Douglas Charley, Department of Geology, Mines, and Water Resources, PMB01, Port-Vila, Vanuatu, Oceania (Email: charley@vanuatu.com.vu).
Nyamuragira
eastern Africa
1.408 S, 29.20 E; summit elev. 3,058 m
All times are local (= UTC + 2 hours)
Nyamuragira, Africa's most active volcano, was the subject of recent reports from USAID/OFDA, volcanic observatories and research centers, Reuters news, and satellite remote-sensing observers. Our last report on Nyamuragira was in late January 2000 (see Bulletin v. 25, no. 1). The volcano is situated about 40 km NE of the city of Goma in an area held by the rebel group Congo Rally for Democracy.
Field reports. A preliminary USAID/OFDA report provided by Jim Smith indicated that Nyamuragira began erupting at 0032 on 6 February. Observations made during a flight over the volcano revealed that there were active lava flows. The lava appeared to be flowing from two fissures; one to the W towards the town of Kitchanga, and another to the S in the direction of both the town of Mugunga (Sake) and Nyiragongo volcano. Smoke was observed near Nyamuragira and thunder was heard. Cloudy conditions prevented clear views of the volcano. These observations were confirmed subsequently by reports received from Hiroyuki Hamaguchi, Tohoku University, and his collaborator, Akumbi Mbilizi, Observatore Volcanologie de Goma.
News reports from Reuters. An 18 February Reuters news article by Jean-Baptiste Kayigamba reported that the volcano spewed large amounts of molten lava from three cones with "flames" rising 100 m above the volcano. The lava flowing down the mountain threatened both the roads running N from Goma and a wide area of the rebel-held territory that lies near the border between the Democratic Republic of Congo (formerly Zaire) and Rwanda.
Reuters noted further that experts at the Lwiro Natural Science Research Centre in Bukavu, S of Goma, said abnormal activity was detected in December. The initial eruption on February 6 gradually increased, and showers of volcanic ash fell on an area estimated at between 20 km^2 and 30 km^2. Officials say the effect on crops and pastures used for grazing will be devastating, and water supplies are likely to be contaminated over a wide area. The news report mentioned that Noel Kiloha, a volcanologist who worked for the Belgian Institute for Scientific Research in the area before independence, will continue to monitor the situation. He told Reuters: "We believe the eruption will continue for several weeks-we still hear terrible underground rumblings." One casualty was reported; a man lost his leg when he accidentally stepped into a lava flow.
Remote thermal data. Scientists from the University of Hawaii used Moderate Resolution Imaging Spectrometer (MODIS), an instrument carried aboard NASA's Earth Observing System satellites) to image thermal anomalies associated with the eruption. MODIS provides high radiometric sensitivity (12 bit) in 36 spectral bands ranging in wavelength from 0.4 um to 14.4 um. Two bands image at a nominal resolution of 250 m at nadir, five bands at 500 m and the remaining 29 bands at 1,000 m.
MODIS observed no hot spots prior to detecting a ~7 x 5 km anomaly centered 7-10 km N of the volcano summit on 7 February. By 8 February, the northern anomaly had increased in size and was orientated in a SSW-NNE direction, and a second anomaly had appeared just to the SSE of the summit. The latter was ~13 x 6 km in size, oriented in an E-ESE direction. On 11 and 12 February, the two anomalies had the same distribution and orientation, both showing an alignment along a SSE-NNW line drawn through the summit. The E-trending S flank hot spot had attained a maximum dimension of ~17 km, while that of the NNE-trending N flank was ~22 km.
Background. Africa's most active volcano, Nyamuragira is a massive basaltic shield volcano north of Lake Kivu and NW of Nyiragongo volcano, along the border between Rwanda and the Democratic Republic of Congo. Lava flows from Nyamuragira cover 1,500 km^2 of the East African rift. The summit is truncated by a small 2 x 2.3 km summit caldera that has walls up to about 100 m high. Some historical eruptions have occurred within the summit caldera, modifying the morphology of the caldera floor. Other eruptions have issued from the numerous fissures and cinder cones on the volcano's flanks. Flank radial fissure activity has been common in the 30 eruptions known since 1882. A lava lake in the summit crater, active since at least 1921, drained in 1938. Twentieth-century flank lava flows extend more than 30 km from the summit, reaching as far as Lake Kivu.
Information Contacts: Andy Harris, Eric Pilger, and Luke Flynn, HIGP/SOEST, University of Hawaii, 2525 Correa Road, Honolulu, HI 96822 (Email: harris@pgd.hawaii.edu, pilger@pgd.hawaii.edu, flynn@pgd.hawaii.edu); MODIS, Vincent Salomonson (Team Leader), NASA's Goddard Space Flight Center, Code 974, Greenbelt, MD 20771 USA http://ltpwww.gsfc.nasa.gov/MODIS/
Topic 2 of 99 [Geo]: Vulcanism
Response 370 of 997: Marcia (MarciaH) * Sat, Mar 10, 2001 (16:16) * 67 lines
Guagua Pichincha
north-central Ecuador
0.171 S, 78.598 W; summit elev. 4,784 m
All times are local (= UTC - 5 hours)
Although previous reports discussed events through July 2000 (Bulletin v. 25, no. 6; v. 25, no. 3; v. 24, no. 12), a summary for the entire year has become available and in the interest of evenness of coverage will be reviewed here. A second, brief report is also included, covering events through mid-January. This latter report includes a tragic event that took place on 14 January 2001, the death of the energetic Instituto Geofisico volcano seismologist Diego Viracucha (see Obituary).
Activity during the year 2000 was generally more moderate than during 1999. The dome that started to form on 18 December 1999 ("dome 8") maintained a slow rate of growth until 23 July 2000 when it was disrupted by a series of small explosions. This growth brought about clear and continuous changes in dome morphology, abundant long-period (LP) earthquakes (monthly averages of ~8,700), and numerous seismically detected rock falls (monthly averages of ~3,000). The 23 July 2000 explosions were also accompanied by pyroclastic flows that descended the Cristal river but apparently did not make it to the confluence with the Cinto river as they had in 1999. Moreover, the 23 July 2000 explosions also failed to create a massive ash plume with its attendant disruption to local inhabitants.
After the 23 July explosions, the subsequent extrusions creating the next dome ("dome 9") were accompanied by abnormally high seismicity. For example, there were 20,646 LP earthquakes monthly starting in August 2000. Around this time, signals for rockfalls totaled ~5,400 a month. Starting on 18 December dome 9 grew comparatively slowly with few morphological changes, but was again accompanied by high, though more moderate seismicity (until December 2000 signals included 11,498 LP events and 3,475 rockfalls). In early 2001, the volume of dome 9 stood at 3 x 10^6 m^3, only about 14% smaller than its predecessor, dome 8.
The external flanks deformed after July 2000. Specifically, radial deflation on the E flank (Refugio station) reached 60 urad. This small-to-moderate deflation was the largest yet seen since the onset of the crisis.
In late 2000 and earliest 2001 with the continuing growth of dome 9, Guagua Pichincha had ~100 earthquakes per day, considerably fewer than in some previous months. Still, in the week of 7-13 January, the volcano's LP earthquakes appeared to have greater magnitudes and source depths because they registered significantly at stations located 10 km out from the crater. Tectonic earthquakes 10 km SW of the crater also registered. Field observers on 14 January attempted to correlate these new, stronger LP earthquakes to visible changes or processes. The observers saw a new crater forming within dome 9, but otherwise, they noted few other surface manifestations that could be linked to the LP earthquakes.
Background. Guagua Pichincha and the older Pleistocene Rucu Pichincha stratovolcanoes rise immediately W of Quito at the W end of the 25-km-long volcanic complex. The horseshoe-shaped summit crater, ~2 km in diameter and 600 m deep, was breached to the W during a slope failure ~50,000 years ago. Subsequent late-Pleistocene and Holocene eruptions from the central vent consisted of explosive activity with pyroclastic flows accompanied by periodic lava dome growth and destruction. Many minor eruptions have occurred since the Spanish colonial era. A central lava dome was probably emplaced during the volcano's largest historical eruption, in 1660, that dropped 30 cm of ash on Quito and generated W-flank pyroclastic flows. The volcano has no permanent ice cap. Seismic data has been collected intermittently since 1977 and continuously since 1981 by the Instituto de Geofisico, Escuela Politecnica. They installed a 6-station telemetered seismic network in August 1988. Phreatic activity from the NE flank of the lava
ome in 1981 and 1982 ejected a small amount of ash and blocks. A single phreatic explosion occurred from the same area in 1985.
Since October 1999 a series of large and small eruptions have blanketed Quito and surrounding towns with silty ash. The high viscosity of the lava erupting suggests effusions will result in dome building rather than extended lava flows. The eighth dome in the current cycle began growing in January 2000 and is becoming increasingly unstable.
Information Contact: Instituto Geofisico (IG), Escuela Politecnica Nacional, Apartado 17-01-2759, Quito, Ecuador (URL: http://www.epn.edu.ec/~igeo/).
Cleveland
Aleutian Islands, USA
52.82 N, 169.95 W; summit elev. 1,730 m
All times are local (= UTC - 8 hours)
At 0600 on 19 February workers at the Alaska Volcano Observatory (AVO) using satellite imagery detected an ash cloud emanating from Cleveland volcano. The eruption was apparently explosive (figure 10). According to images captured at 0945 the ash cloud had split and drifted in two directions; one traveled 120 km SE of the volcano and reached an altitude of over 5 km, while the other cloud drifted higher, traveled 100 km N, and rose to an altitude of over 9 km (figure 11). A volcanic ash advisory was first issued at 1040 on the same day indicating that ash was being carried E at a velocity of ~55 km/hour and had reached an altitude of over 10 km. Subsequent pilot reports and satellite data revealed a diminishing intensity of the ash issuing from Cleveland, although observers in Nikolski, 72 km to the E, reported ashfall initiating at 1200 and persisting through 1600. Explosive activity ended by late afternoon.
Figure 10. Cleveland on 21 February. The usually white, snow-covered flanks are shown darkened by ash from the eruption. Photo was taken by Burke Mees (PenAir pilot) and transmitted courtesy of AVO.
Figure 11. Composite of GOES images showing the progressive locations and evolution of the ash clouds erupted from Cleveland during 19-21 February. The initial image of the plume (far left) was taken at 0815 on 19 February approximately 2 hours after the eruption began (labeled "2/19/01, 1615 Z"). Over time the plume bifurcated, sent ash SE to an altitude of 6 km, and ash N and slightly W to an altitude of 9 km. Ash clouds rose to a maximum altitude of over 10 km (roughly "FL330," aviation shorthand for 33,000 feet) before dissipating. Times are listed in UTC (not local time). The image also highlights the importance of quickly relaying information from volcano observatories to airline dispatchers in order to keep pilots aware of potential ash along their routes. Only areas of detected ash are shown, and ash may be present elsewhere. Image noise has been removed for clarity. Courtesy of AVO.
AVO workers observed a persistent large thermal anomaly at the volcano, which indicated that further eruptions could occur at any time. Pilots flying near the volcano late on 21 February confirmed no further ash production, but one did observe steaming near the termination of a flow on the volcano's SW flank. The steaming was located where rubbly, apparently hot debris entered the sea, and could have been an active lava flow or a fan of debris; it likely explains the thermal anomaly detected in satellite images. A thermal anomaly continued to be detected as of 26 February, suggesting that low-level activity was still occurring. No level of concern color codes were assigned for Cleveland because AVO has no seismic monitoring stations at the volcano.
Even after the eruption ceased, the eastward drifting ash-and-steam cloud continued to be a hazard to aviators (figure 11). The SE portion of the plume approached the westernmost point of Umnak Island by 1030 on the day of the eruption, and the entire plume was carried farther E so that it reached Dutch Harbor and Akutan by 1900.
Satellite imagery at 0730 on 20 February showed the ash cloud as a band extending from S of Port Heiden to N of Nunivak Island. No ashfall was reported at Dutch Harbor, Port Heiden, or Dillingham, however.
By 0530 on 21 February the cloud could be seen on satellite imagery stretching from near Montague Island S about 150 km over the northern portion of the Gulf of Alaska. The ash band dissipated and became undetectable in satellite images by about 1700 on 21 February. A smaller ash cloud may also have drifted over interior Alaska reaching N of Fairbanks, but it became indistinguishable from weather clouds by the same time.
Background. The symmetrical Mount Cleveland stratovolcano is situated at the western end of the dumbbell-shaped Chuginadak Island. The 1,730-m-high stratovolcano is one of the most active volcanoes of the Aleutian Islands and has numerous large lava flows on its flanks. In 1944 Cleveland produced the only known fatality from an Aleutian eruption. It is possible that some 18th to 19th century eruptions attributed to Carlisle volcano, located across the Carlisle Pass strait to the NW, should be ascribed to Cleveland (Miller and others, 1998).
Reference: Miller, T.P., McGimsey, R.G., Richter, D.H., Riehle, J.R., Nye, C.J., Yount, M.E. and Dumoulin, J.A., 1998, Catalog of the historically active volcanoes of Alaska: U.S. Geological Survey Open-File Report 98-582, Alaska Volcano Observatory, Alaska, 1998. 104 p.
Information Contacts: Alaska Volcano Observatory (AVO), a cooperative program of (a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667 USA (Email: tlmurray@usgs.gov; URL: http://www. avo.alaska.edu/), (b) Geophysical Institute, University of Alaska, P.O. Box 757320, Fairbanks, AK 99775-7320 USA (Email: eich@giseis.alaska.edu), and (c) Alaska Division of Geological & Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709 USA (Email: cnye@giseis.alaska.edu); Anchorage Volcanic Ash Advisory Center (VAAC), 6930 Sand Lake Road, Anchorage, AK 99502, USA (URL: http://www.ssd.noaa.gov/VAAC/ OTH/AK/messages.html).
Obituary
Diego Viracucha, an accomplished 37-year-old mountaineer and for 9 years a volcano seismologist at the Instituto Geofisico, looked into the crater on the morning of 14 January 2001 and reported his impressions via radio. He informed his two assistants that he was going to go ahead alone for several hundred meters W of the seismic station "Pino" in order to take photos. He planned to return in 20 minutes and remain in contact via radio, but later attempts to contact him failed. Apparently he slipped and fell over the caldera rim, a 200- to 300-m-high cliff in that region; his body was found hours later. Given the length of the fall and the impact, he probably died immediately from head wounds and internal injuries.
Recovery of the body was accomplished using mountaineering techniques rather than a helicopter due to fog. The day-long effort involved many, including six IG volcanologists, the Civil Defense, the Guards of the Refuge, the Red Cross, an elite police group, mountaineer groups, and family members. The site of the accident was 2.5 hours from GGP Refuge and it took all day to recover the body. A second accident occurred during this effort when Galo Viracucha, a cousin of Diego, fell and rolled 150 m downslope and later died from his injuries.
Diego had studied the seismic patterns of Cotopaxi, Guagua Pichincha, Cayambe and Tungurahua. He was an accomplished mountaineer and had scaled almost all of the important peaks of Ecuador's volcanoes. One of his greatest passions since September 1999 was keeping a close visual-photographic record of the changes in the domes of Guagua Pichincha. His excellent companionship, his unflagging enthusiasm, his well-stilled knowledge of the seismicity of the active volcanoes--leaves a tremendous void in the Instituto's monitoring efforts.
_____________________________________________________________________
Ed Venzke
Global Volcanism Program, NMNH E-421 Tel: (202) 357-2822
Smithsonian Institution Fax: (202) 357-2476
Washington, DC 20560-0119 Email: venzke@volcano.si.edu
GVP Webmaster http://www.volcano.si.edu/gvp/
____________________________________________________________________
Topic 2 of 99 [Geo]: Vulcanism
Response 371 of 997: Marcia (MarciaH) * Fri, Mar 16, 2001 (11:49) * 82 lines
U.S. Geological Survey
Hawaiian Volcano Observatory
PO Box 51, Hawaii National Park, HI 96718
Phone (808) 967-7328 FAX (808) 967-8890
Volcano Watch - March 15, 2001
Professor Fusakichi Omori - an instrumental person at HVO
The U.S. Geological Survey's Hawaiian Volcano Observatory currently
operates a network of 65 seismic stations. Signals from each station,
including the four on Maui, are radio-telemetered to HVO and recorded.
When an earthquake is detected, the arrival time of the earthquake at each
station is timed, and an epicenter is determined within a few seconds. It
takes a few minutes longer to calculate a magnitude. Then the location and
magnitude of the event are posted on our web site (http://hvo.wr.usgs.gov).
The present high-tech seismic operation at HVO had a humble beginning
92 years ago. In his preparation for establishing a volcano observatory,
Thomas A. Jaggar traveled to Japan in 1909 to learn about Japanese
seismological methods. He met with Professor Fusakichi Omori, head of the
Seismological Institute of the Tokyo Imperial University. Thus began a
long friendship that lasted until Professor Omori's death in 1923. HVO
greatly benefited from this personal relationship.
The meeting in Japan resulted in the presentation to Dr. Jaggar of an
Omori seismograph, various seismological publications, and a set of
construction plans for a seismic vault. When the original HVO was built at
the site of the present Volcano House hotel, a basement was dug, and the
Whitney Seismological Laboratory was constructed in accordance with the
plans of Professor Omori. The first instrument installed was the Omori
seismograph, followed a year later by two Bosch-Omori seismographs
purchased by the Massachusetts Institute of Technology. These instruments
were entirely mechanical, with amplification of the horizontal ground
movement dependent upon the length of the weighted pendulum arm.
Variations of these instruments were the main seismic detectors for
40 years until 1953, when electromagnetic sensors were introduced. One
instrument, which was also used for tilt measurements, however, remained in
operation until 1963, when the Whitney vault was abandoned. The National
Park Service is now in the process of restoring the vault and
reestablishing the seismographs.
In addition to his seismographs, HVO used the methodology developed
by Professor Omori to locate earthquakes. The tables or traveltimes of
different earthquake waves published by Professor Omori were ideal for
locating local Hawaiian earthquakes. Of greater importance to HVO were the
publications describing the physical, petrologic, geodetic and seismometric
data of Japanese volcanic eruptions by Professor Omori and his colleagues.
Professor Omori's accounts of the 1914 eruption of Sakurajima Volcano
are classic. The description of the eruption, earthquake activity, ground
deformation, gases, eruptive products and societal concerns are covered.
Jaggar patterned his volcano monitoring efforts to detect precursory
signals reported by Professors Omori and Koto.
The technology and techniques used to monitor volcanoes today may
have changed, but the precursory phenomena remain the same. Thomas A.
Jaggar would be proud if he could now see the Observatory that he
established and the earthquake monitoring program built upon his friendship
with Fusakichi Omori. But he wouldn't be surprised by our rapid detection
and reporting capabilities; he foresaw that in 1941!
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week and provided visitors with an occasional
glimpse of surface flow activity on Pulama pali and on the coastal flats.
Lava is pooling in the coastal flats and not entering the ocean at this
time. The broad active flow front extends 1.5 km (0.9 mi) to the west from
the end of the Royal Gardens private access road. A small lobe of the flow
front is now only 0.3 km (0.2 mi) from the sea coast.
One earthquake was reported felt during the week ending on March 15.
Residents of Pahala and Hawaiian Ocean View Estates felt an earthquake at
5:05 a.m. on Sunday, March 11. The magnitude-3.4 earthquake was located 4
km (2.4 mi) north of Pahala at a depth of 6.5 km (3.9 mi).
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
Carolyn Bell
Public Affairs Specialist
U.S. Geological Survey
Mail Stop 119 National Center
Reston, VA 20192
Phone: 703-648-4463
Fax: 703-648-4466
Topic 2 of 99 [Geo]: Vulcanism
Response 372 of 997: Marcia (MarciaH) * Sat, Mar 17, 2001 (17:37) * 136 lines
*******************************************
GVP/USGS Weekly Volcanic Activity Report
7-13 March 2001
**************************************
http//www.volcano.si.edu/gvp/usgs/
New Activity/Unrest | Cleveland, USA | Mayon, Philippines | Nyamuragira, DR Congo |
Nyiragongo, DR Congo |
Ongoing Activity | Etna, Italy | Kilauea, USA | Kliuchevskoi, Kamchatka | Lokon-Empung,
Indonesia | Merapi, Indonesia | Popocatépetl, México | Shiveluch, Kamchatka |
Soufrière Hills, Montserrat |
New Activity
CLEVELAND Aleutian Islands, USA 52.82°N, 169.95°W; summit elev. 1,730 m; All times are local (= UTC- 9 hours)
The AVO reported that an explosive eruption at Cleveland began at 0500 on 11 March. The resultant ash cloud was visible on satellite imagery from the onset of the eruption and after it ended 3 hours later. Wind-data analysis suggested that the ash cloud reached a height of 6-7.6 km a.s.l. By 1400 the main part of the ash cloud was detached from the volcano and drifting to the E. Satellite imagery from 2030 showed that the ash cloud was located in two main regions; one region was centered ~80 km S of Dutch Harbor and was ~80 km in diameter, and the other was centered ~160 km SE of Dutch Harbor and extended ~160 km E to W and ~65 km N to S. Both areas of ash were visible on satellite imagery through 1315 on 12 March. In addition, a thermal anomaly on the volcano, which was first detected shortly after the eruption began, persisted. AVO interpreted the thermal anomaly to indicate that unrest was continuing at Cleveland and that further explosive activity could occur at anytime. By 0930 on 13 March the ash clou
was no longer visible on satellite imagery.
Background. The symmetrical Mount Cleveland stratovolcano is situated at the western end of the uninhabited dumbbell-shaped Chuginadak Island in the east-central Aleutians. The 1,730-m-high stratovolcano is the highest of the Islands of Four Mountains volcanoes and is one of the most active in the Aleutians. Numerous large lava flows descend its flanks. It is possible that some 18th to 19th century eruptions attributed to Carlisle volcano, located across the Carlisle Pass Strait to the NW, should be ascribed to Cleveland. In 1944 Cleveland produced the only known fatality from an Aleutian eruption. Recent eruptions from Mt. Cleveland have been characterized by short-lived explosive ash emissions, at times accompanied by lava fountaining and lava flows down the flanks.
Source Alaska Volcano Observatory http//www.avo.alaska.edu/avo4/updates/updates.htm
Anchorage VAAC http//www.ssd.noaa.gov/VAAC/OTH/AK/messages.html
Tokyo VAAC http//www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
Cleveland Reports http//www.volcano.si.edu/gvp/volcano/region11/aleutian/cleve/var.htm
from the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev. 2,462 m; All times are local (= UTC + 8 hours)
PHIVOLCS reported that during 7 to 13 March, 6-33 low-frequency earthquakes were recorded daily. One SO2 emission measurement was made during the week on 4 March, with a reading of 1,750 metric tons. Like the previous weeks, a slight inflationary trend was detected at the volcano's edifice and weak-to-moderate steaming was occasionally seen. At 1509 on 11 March a brief ash discharge reached a height of 150 m and drifted to the SW. At 1940 the same day faint incandescence was observed at the crater using a telescope; graded as level 1 intensity. Mayon remained at Alert Level 3 (on a scale of 0-5).
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462 m above the Albay Gulf, is the Philippines' most active volcano. The structurally simple volcano has steep upper slopes that average 35-40° and is capped by a small summit crater. The historical eruptions of this basaltic-andesitic volcano date back to 1616 and range from Strombolian to basaltic Plinian. Eruptions occur predominately from the central conduit and have also produced lava flows that travel far down the flanks. Pyroclastic flows and mudflows have commonly swept down many of the approximately 40 ravines that radiate from the summit and have often devastated populated lowland areas. Mayon's most violent eruption, in 1814, killed more than 1,200 people and buried an entire town in volcanic mud. Eruptions that began in February 2000 led PHIVOLCS to recommend on 23 February 2000 the evacuation of people within 7 km of the summit in the SE and within 6 km for the rest of the volcano.
Source Philippine Institute of Volcanology and Seismology,
http//www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
http//www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm
from the monthly Bulletin of the Global Volcanism Network
NYAMURAGIRA Democratic Republic of the Congo 1.408°S, 29.20°E; summit elev. 3,058 m
The eruption at Nyamuragira that began on 5 February continued, with lava flows mainly traveling down the S flank of the volcano. The UN Integrated Regional Information Network reported on 27 February that a UN-government assessment team that visited the town of Goma, ~40 km S of the volcano, determined that ash and lava from the eruption had damaged agriculture and livestock. The team warned that there was an urgent need for food, medicine, and vegetable seeds in the affected areas of Goma, Kitshanga, and Kalungu. According to the Goma Volcanological Observatory, a new eruption began on 2 March with eruptive activity concentrated mainly on the S flank. The Observatory stated that wind had blown ash towards the W and ash fall had destroyed ~50 km2 of pasture and 150 km2 of crops up to 30 km from the volcano in the towns of Rusaya, Kirolirwe, Burungu, Minova, the Masisi territory, and the S part of Kichanga. Ash and gas from the eruption have caused many people in those areas and Goma to experience fever, di
rrhea, headache, conjunctivitis, and respiratory problems.
Background. Africa's most active volcano, Nyamuragira is a massive basaltic shield volcano N of Lake Kivu and NW of Nyiragongo volcano. Lava flows from Nyamuragira cover 1,500 sq km of the East African Rift. The 3058-m-high summit is truncated by a small 2 x 2.3 km summit caldera that has walls up to about 100 m high. About 40 historical eruptions have occurred since the mid-19th century within the summit caldera and from numerous fissures and cinder cones on the volcano's flanks. A lava lake in the summit crater, active since at least 1921, drained in 1938. Twentieth-century flank lava flows extend more than 30 km from the summit, reaching as far as Lake Kivu.
Sources. Goma Volcanological Observatory
UN Integrated Regional Information Network http//www.congo2000.com/english/news/index.htm
Reuters http//www.enn.com/news/wire-stories/2001/03/03112001/reu_lava_42467.asp
Nyamuragira Reports http//www.volcano.si.edu/gvp/volcano/region02/africa_e/nyamura/var.htm
from the monthly Bulletin of the Global Volcanism Network
NYIRAGONGO Democratic Republic of the Congo 1.52°S, 29.25°E; summit elev. 3,469 m
The Goma Volcanological Observatory reported that there may be renewed volcanic activity at Nyiragongo volcano, ~10 km SE of Nyamuragira volcano. The observatory stated that during the current eruption of Nyamuragira the temperature increased in Nyiragongo's main cone and Shaheru fissure, ~3 km S of the summit. In addition, new fumaroles were observed inside Nyiragongo's main crater and along the fissure connecting the main crater and Shaheru cone. Cracks that were observed in the crater of the main cone suggested that dilatation of the crater had occurred.
Background. One of Africa's most notable volcanoes, Nyiragongo contained an active lava lake in its deep summit crater that drained catastrophically through its outer flanks in 1977. In contrast to the low profile of its neighboring shield volcano, Nyamuragira, Nyiragongo displays the steep slopes of a stratovolcano. Benches in the steep-walled, 1.2-km-wide summit crater mark the levels of former lava lakes, which have been observed since the late 19th century. About 100 parasitic cones are located on the volcano's flanks and along a NE-SW zone extending as far as Lake Kivu. Monitoring is done from a small observatory building located in Goma, ~18 km S of the Nyiragongo crater.
Source Goma Volcanological Observatory
Nyiragongo Reports http//volcano.si.edu/gvp/volcano/region02/africa_e/nyiragon/var.htm
from the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
According to the Italy's Volcanoes website, during the first half of March mild, but occasionally vigorous eruptive activity continued at Etna's summit craters much like it has since mid January. Near-continuous Strombolian activity continued at two vents in Bocca Nuova Crater and Strombolian activity intermittently occurred within the central pit of the Northeast Crater. Short lobes of lava continued to form after slowly emerging from a vent on the NNE flank of the Southeast Crater cone.
Background. Mount Etna, towering above Catania, Sicily's second largest city, has one of the world's longest documented records of historical volcanism, dating back to 1500 BC. Historical lava flows cover much of the surface of this massive basaltic stratovolcano, the highest and most voluminous in Italy. Two styles of eruptive activity typically occur at Etna. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more of the three prominent summit craters Central Crater, NE Crater, and SE Crater. Flank eruptions, typically with higher effusion rates, occur less frequently and originate from fissures that open progressively downward from near the summit. A period of more intense intermittent explosive eruptions from Etna's summit craters began in 1995.
Source Italy's Volcanoes http//www.geo.mtu.edu/~boris/ETNA_intro.html
Etna Reports
http//www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.
from the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava slowly flowed SE down the Pulama pali and across the coastal plain in a broad flow front, ~1.5 km wide. Much of the flow front was within 1-1.3 km of the coastline, with the closest point ~700 m from the coast. Overall, volcanic tremor near Pu`u `O`o was low-to-moderate and tremor at Kilauea's caldera was low. Tiltmeters in the summit area and along the E rift zone showed flat signals.
Background. Kilauea, one of five coalescing volcanoes that comprise the island of Hawaii, is one of the world's most active volcanoes. Historically its eruptions originate primarily from the summit caldera or along one of the lengthy E and SW rift zones that extend from the caldera to the sea. The latest Kilauea eruption began in January 1983 along the E rift zone. The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive episode. Since 1986, flows have traveled 11-12 km from the vents to the sea, paving about 80 km2 of land on the S flank of Kilauea and building 205 hectares of new land. Intensive monitoring and field research by staff of the US Geological Survey's Hawaiian Volcano Observatory, established in 1912, make Kilauea one of Earth's best studied volcanoes.
Source US Geological Survey Hawaiian Volcano Observatory http//hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http//www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
KLIUCHEVSKOI Kamchatka Peninsula, Russia 56.06°N, 160.64°E; summit elev. 4,835 m
The KVERT reported that during 2-8 March seismicity was at background levels, with weak spasmodic tremor occasionally registered. On 4 March a gas-and-steam plume rose 600-1,000 m above the volcano and extended more than 10 km to the NE. As reported by the Tokyo VAAC, GMS-5 imagery showed that the plume rose to a height of ~9.5 km a.s.l. The Concern Color Code remained at Green.
http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Background. Kliuchevskoi is Kamchatka's highest and most active volcano. Since its origin about 7,000 years ago, the beautifully symmetrical, 4,835-m-high basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. More than 100 flank eruptions, mostly on the NE and SE flanks of the conical volcano between 500 m and 3,600 m elevation, have occurred during the past 3,000 years. The morphology of its 700-m-wide summit crater has been frequently modified by historical eruptions, which have been recorded since the late-17th century. Historical eruptions have originated primarily from the summit crater, but have also included major explosive and effusive events from flank craters.
Source Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano Observatory http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Tokyo VAAC http//www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
Kliuchevskoi Reports http//www.volcano.si.edu/gvp/volcano/region10/kamchat/kliuchev/var.htm
from the monthly Bulletin of the Global Volcanism Network
LOKON-EMPUNG northern Sulawesi, Indonesia 1.36°N, 124.79°E; summit elev. 1,580 m
The VSI reported that visual observations made during 27 February to 5 March revealed that activity decreased at Lokon-Empung. Only small-to-medium sized steam plumes were observed rising 50-150 m above the crater. The Alert level was reduced from 3 to 2 (on a scale of 1-4).
Background. The twin volcanoes Lokon and Empung, rising about 800 m above the plain of Tondano, are among the most active volcanoes of Sulawesi. Lokon, the higher of the two peaks (whose summits are only 2.2 km apart) has a flat, craterless top. The morphologically younger Empung volcano has a 400-m-wide, 150-m-deep crater that erupted last in the 18th century, but all subsequent eruptions have originated from Tompaluan, a 150 x 250 m wide double crater situated in the saddle between the two peaks. Historical eruptions have primarily produced small-to-moderate ash plumes that have occasionally damaged croplands and houses, but lava-dome growth and pyroclastic flows have also occurred.
Source Volcanological Survey of Indonesia, http//www.vsi.dpe.go.id/news/index.html
Lokon-Empung Reports
http//www.volcano.si.edu/gvp/volcano/region06/sulawesi/lokon/var.htm
from the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
Visual and instrumental monitoring conducted by VSI personnel revealed that volcanic activity at Merapi had decreased; therefore on 7 March the Alert Level was reduced from 3 to 2 (on a scale of 1-4). During 27 February- 5 March, volcanic activity was dominated by an average of 100 lava avalanches per day. The avalanche material traveled to the SW, entering the Sat and Senowo rivers with runout distances of 2.3-2.5 km. On 6 March a pyroclastic flow deposited material up to 1.5 km down the Sat River.
Background. Merapi, one of Indonesia's most active volcanoes, lies in one of the world's most densely populated areas and dominates the landscape immediately N of the major city of Yogyakarta. The steep-sided modern Merapi edifice, its upper part unvegetated due to frequent eruptive activity, was constructed to the SW of an arcuate scarp cutting the eroded older Batulawang volcano. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated and inhabited lands on the volcano's western-to-southern flanks and caused many fatalities during historical time. The volcano is the object of extensive monitoring efforts by the Merapi Volcano Observatory of the Volcanological Survey of Indonesia.
Source Volcanological Survey of Indonesia, http//www.vsi.dpe.go.id/news/index.html
Merapi Reports
http//www.volcano.si.edu/gvp/volcano/region06/java/merapi/var.htm
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are local (= UTC 6 hours)
CENAPRED reported that Popocatépetl's activity was at low-to-moderate levels during most of the week, with small exhalations accompanied by steam emissions. Based on reports from the Mexico MWO, the Washington VAAC reported that at 2024 on 12 March an ash cloud from an exhalation of Popocatépetl was observed at a height of ~ 7 km a.s.l. The ash cloud was not visible on GOES-8 imagery. The volcano remained at Alert Level Yellow Phase III, with a restricted area of 12-km-radius.
Background. Popocatépetl, whose name is the Aztec word for smoking mountain, towers to 5,426 m 70 km SE of México City and is North America's second highest volcano. Frequent historical eruptions have been recorded since the beginning of the Spanish colonial era. A small eruption on 21 December 1994 ended five decades of quiescence. Since 1996 small lava domes have incrementally been constructed within the summit crater and destroyed by explosive eruptions. Intermittent small-to-moderate gas-and-ash eruptions have continued, occasionally producing ashfall in neighboring towns and villages.
Photos (CENAPRED site) http//www.cenapred.unam.mx/boletines.html
Sources Centro Nacionale de Prevencion de Desastres, http//www.cenapred.unam.mx/boletines.html
Washington VAAC, http//www.ssd.noaa.gov/VAAC/messages.html
Popocatépetl Reports
http//www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html
from the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev. 3,283 m; All times are local (= UTC + 12 hours)
The KVERT reported that during 2-6 March, several series of shallow earthquakes were registered, with some followed by weak spasmodic volcanic tremor. The bursts of activity may have corresponded to weak ash-and-gas explosions that rose to heights of 2-3 km above the crater. During 3-4 March, visual and satellite-based data revealed that a gas-and-ash plume rose 300-800 m above the crater and drifted more than 50 km to the E. At 1545 on 7 March seismic data indicated the probable occurrence of a short-lived gas-and-ash explosion, accompanied by a series of shallow and high-frequency earthquakes for ~15 minutes. Observers in Klyuchi town reported that at 1600 the same day the ash-and-gas plume rose 1.5 km above the lava dome and extended to the NW. According to a pilot report, at 1620 the ash plume was visible at a height of 10 km above the volcano drifting towards the NE. The AVO reported that satellite imagery at 1715 showed two plumes one was at a low altitude, composed mostly of steam, and drifted to the
E; the other was located 7-8 km a.s.l., composed mostly of ash, and drifted to the N. At 1625 the Tokyo VAAC detected the ash cloud on GMS-5 imagery at a height of ~10 km a.s.l. The ash cloud was no longer visible on satellite imagery by 0342 on 8 March. The Concern Color Code remained at Yellow.
http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Background. The high, isolated massif of Shiveluch volcano (also spelled Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group and forms one of Kamchatka's largest and most active volcanoes. The currently active Molodoy Shiveluch lava-dome complex was constructed during the Holocene within a large breached caldera formed by collapse of the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large eruptions of Shiveluch have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent collapses of lava-dome complexes, most recently in 1964, have produced large debris avalanches whose deposits cover much of the floor of the breached caldera. During the 1990s, intermittent explosive eruptions took place from a new lava dome that began growing in 1980. The largest historical eruptions from Shiveluch occurred in 1854 and 1964.
Source Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano Observatory http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Tokyo VAAC http//www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
Shiveluch Reports http//www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
The MVO reported that during 2-9 March activity decreased at Soufrière Hills volcano in comparison to the previous week, with the lava dome returning to a steady growth rate. Early in the report week the banded tremor recorded the previous week died away, as did the associated hybrid earthquakes. Rockfall activity increased during the middle of the week, returning to more usual levels. The volcano appeared to have resumed steady dome growth by the end of the week. Observations confirmed that the main area of lava-dome growth had switched to the S of the dome on 25 February, which led to a concentration of rockfall activity in the upper portions of the White River Valley. Light ashfall from activity during the week was blown over the N of the island, although by the end of the week the wind switched back to the more usual direction towards the W. The Washington VAAC reported that throughout the week low-level ash clouds (up to ~3 km a.s.l.), presumably produced by rockfalls, and periodic hot-spot activity we
e visible on GOES-8 imagery.
Background. The complex andesitic Soufrière Hills volcano occupies the southern half of the island of Montserrat. The summit area consists primarily of a series of lava domes emplaced along an ESE-trending zone. Non-eruptive seismic swarms occurred at 30-year intervals in the 20th century, but the first well-documented historical eruption on Montserrat did not take place until 1995. Long-term small-to-moderate ash eruptions were accompanied by lava dome growth and pyroclastic flows that initially forced evacuation of the southern half of the island and then destroyed the capital city of Plymouth, causing severe social and economic disruption. The volcano is currently in a period of new dome growth.
Sources Montserrat Volcano Observatory http//www.mvomrat.com/
Washington VAAC http//www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports http//www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
http//www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
mayberry@volcano.si.edu
URL http//www.volcano.si.edu/gvp/usgs/
**********************************************************
Topic 2 of 99 [Geo]: Vulcanism
Response 373 of 997: Marcia (MarciaH) * Tue, Mar 20, 2001 (20:02) * 43 lines
ALASKA VOLCANO OBSERVATORY
Monday, March 19, 2001 2030 AST (March 20, 0530 UTC)
VOLCANIC ACTIVITY REPORT
CLEVELAND VOLCANO (CAVW #1101-24)
52°49'N 169°57'W
Summit Elevation 5,674 ft (1,730 m)
AVO detected an explosive eruption at Cleveland Volcano in satellite
imagery that began about 2330 UTC (1430 AST). According to images from
0330 UTC (1830 AST) the ash cloud is V-shaped with one leg extending to the
east 115 mi (185 km) and the other leg extending to the southeast about 125
mi (200 km). The National Weather Service estimates the top of the cloud
to be 30,000 ft ASL. The eruption may still be continuing as of the latest
satellite image from 0430 UTC (1930 AST). An observer in Nikolski reported
about 0400 UTC (1900 AST) a strong haze resulting from the ash that
extended to the southeast from the volcano, but no ashfall in Nikolski.
Mt. Cleveland forms the western half of Chuginadak Island a remote and
uninhabited island in the east central Aleutians. It is located 40 km (25
mi) west of Umnak Island and 75 km (45 mi) west of the community of
Nikolski. A distinctively symmetrical stratovolcano, Cleveland has erupted
at least 11 times since 1893. An explosive event on February 19, 2001 sent
ash to 35,000 feet (10.5 km) ASL. The March 11, 2001 event produced an ash
plume that reached a height of 20,000-25,000 ft (6.1-7.6 km) ASL.
Eruptions of Mt. Cleveland are characterized by short-lived explosive
bursts of ash, at times accompanied by lava fountaining and lava flows down
the flanks. Cleveland is not monitored seismically, therefore we do not
assign a level of concern color code.
AVO will continue to monitor the situation closely and will issue further
updates as information becomes available.
Abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of Alaska's volcanoes (907) 786-7478
Topic 2 of 99 [Geo]: Vulcanism
Response 374 of 997: Marcia (MarciaH) * Wed, Mar 21, 2001 (19:09) * 343 lines
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GVP/USGS Weekly Volcanic Activity Report
14-20 March 2001
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From Gari Mayberry
GVP/USGS Weekly Volcanic Activity Report
14-20 March 2001
http//www.volcano.si.edu/gvp/usgs/
New Activity/Unrest | Cleveland, USA | Mayon, Philippines | Miyake-jima,
Japan | Piton de la Fournaise, Reunion Island |
Ongoing Activity | Guagua Pichincha, Ecuador | Kilauea, USA |
Kliuchevskoi, Kamchatka | Merapi, Indonesia | Popocatépetl, México |
Shiveluch, Kamchatka | Soufrière Hills, Montserrat | Tungurahua, Ecuador |
New Activity
CLEVELAND Aleutian Islands, USA 52.82°N, 169.95°W; summit elev. 1,730 m;
All times are local (= UTC 9 hours)
The AVO reported that at 1430 on 19 March an explosive eruption at
Cleveland was detected on satellite imagery. The National Weather Service
estimated the top of the cloud to be at ~ 9 km a.s.l. An observer in the
town of Nikolski reported that at about 1900 a strong haze resulting from
the eruption extended SE from the volcano, but there was no ashfall. The
Washington VAAC concluded that the ash cloud had dissipated by 0230 on 20
March because it was no longer visible on satellite imagery.
Background. The symmetrical Mount Cleveland stratovolcano is situated at
the western end of the uninhabited dumbbell-shaped Chuginadak Island in the
east-central Aleutians. The 1,730-m-high stratovolcano is the highest of
the Islands of Four Mountains volcanoes and is one of the most active in
the Aleutians. Numerous large lava flows descend its flanks. It is
possible that some 18th to 19th century eruptions attributed to Carlisle
volcano, located across the Carlisle Pass Strait to the NW, should be
ascribed to Cleveland. In 1944 Cleveland produced the only known fatality
from an Aleutian eruption. Recent eruptions from Mt. Cleveland have been
characterized by short-lived explosive ash emissions, at times accompanied
by lava fountaining and lava flows down the flanks.
Sources Alaska Volcano Observatory
http//www.avo.alaska.edu/avo4/updates/updates.htm, Washington VAAC
http//www.ssd.noaa.gov/VAAC/messages.html
Cleveland Reports
http//www.volcano.si.edu/gvp/volcano/region11/aleutian/cleve/var.htm
from the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
PHIVOLCS reported that during 15 to 19 March, 10-37 low-frequency
earthquakes were recorded daily. An average of 2,900 metric tons per day
(t/d) of SO2 was recorded during the previous week, which was significantly
above the baseline value of 500 t/d. Many days a slight inflationary trend
was detected at the volcano’s edifice and moderate steaming was seen. No
incandescence was observed at the crater. PHIVOLCS warned that instrumental
and visual observations suggested that an eruption may occur in the coming
weeks and that the volcano remained at Alert Level 3. Observations revealed
that the lava dome growing at the summit had overlapped the pre-existing SE
rim of the summit crater. Further growth of the lava dome towards the SE
could result in rockfalls and avalanches that would be channeled down the
SE-flank Bonga Gully. In addition, large pyroclastic flows could occur down
the volcano’s SE slope.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon's most violent eruption, in 1814,
killed more than 1,200 people and buried an entire town in volcanic mud.
Eruptions that began in February 2000 led PHIVOLCS to recommend on 23
February 2000 the evacuation of people within 7 km of the summit in the SE
and within 6 km for the rest of the volcano.
Source Philippine Institute of Volcanology and Seismology
http//www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
Mayon Reports
http//www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm
from the monthly Bulletin of the Global Volcanism Network
MIYAKE-JIMA Izu Islands, Japan 34.08°N, 139.53°E; summit elev. 815 m
Based on information from the Japan Meteorological Agency, the Kyodo news
agency reported that on 16 March volcanic tremor was recorded at
Miyake-jima. The tremor was the strongest to be recorded since 29 August
2000. On 19 March an eruption produced a black ash cloud that rose 800 m
above the volcano. The island is currently uninhabited because the current
volcanic activity that began on 26-27 June 2000 led officials to order an
evacuation on 1 September 2000.
Background. The circular, 8-km-wide island of Miyake-jima forms a low-angle
stratovolcano with a 3-km-wide summit caldera partially filled by the
summit cone Oyama (many reports call the volcano Oyama). Parasitic craters
and vents, including maars near the coast and radially oriented fissure
vents, dot the volcano. Frequent historical eruptions have originated at
vents ranging from the summit to sea level, causing much damage. The
previous eruption of Miyake-jima occurred in 1983; it forced ~4,000
residents to evacuate the island. There were no injuries or fatalities
reported then, but basaltic lava flows destroyed 80% of the W-flank town of
Ako and reached the sea on the SW coast.
Source Kyodo News http//home.kyodo.co.jp/
Miyake-jima Reports
http//ww.volcano.si.edu/gvp/volcano/region08/ivm_arc/miyake/var.htm
from the monthly Bulletin of the Global Volcanism Network
PITON DE LA FOURNAISE Réunion Island, Indian Ocean 21.23°S, 55.71°E
The OVPDLF reported that instrumental measurements suggest that Piton de la
Fournaise may be entering a phase of heightened activity. Periods of
increased seismic activity were recorded in late January with up to 13
earthquakes per day, in late February to early March with up to 126
earthquakes per day, and from 10 March until at least 15 March with up to
20 earthquakes per day. Inflation was detected at the volcano’s summit from
mid-January to early February, and from the end of February to early March.
Since mid-January a continuous opening of fissures was recorded at the N
and S bases of the volcano, indicating inflation of the summit area.
Similar variations in activity were observed before eruptions on the E and
S flanks of the volcano in 1999 and 2000.
Background. The massive Piton de la Fournaise shield volcano on the island
of Réunion is one of the world's most active volcanoes. Most historical
eruptions have originated from the summit and flanks of a 400-m-high lava
shield, Dolomieu, which has grown within the youngest of three large
calderas. This depression is 8 km wide and is breached to below sea level
on the eastern side. More than 150 eruptions, most of which have produced
fluid basaltic lava flows within the caldera, have been documented since
the 17th century.
Source Observatoire Volcanologique du Piton de la Fournaise
http//volcano.ipgp.jussieu.fr8080/reunion/stationreu2.html
Piton de la Fournaise Reports
http//www.volcano.si.edu/gvp/volcano/region03/indian_w/pdlf/var.htm
from the Bulletin of the Global Volcanism Network
Ongoing Activity
GUAGUA PICHINCHA north-central Ecuador 0.17°S, 78.60°W; summit elev. 4,784
m; All times are local (= UTC 5 hours)
Based on information from the IG, the Washington VAAC reported that a
moderate ash emission at 2145 on 18 March produced an ash cloud that rose
to a height of ~5.8 km a.s.l. The ash cloud was not visible on GOES-8
imagery. According to the IG, during the week a large number of
earthquakes, especially long-period events, were registered. The detection
of a small number of rockfalls confirmed that lava dome 9 continued to
slowly grow. The volcano remained at Alert Level Yellow
http//www.epn.edu.ec/~igeo/Vulcanologia/Alarmas/alarmas.htm
Background. Guagua Pichincha rises immediately W of Quito, Ecuador’s
capital city. The broad volcanic massif is cut by a large horseshoe-shaped
summit caldera, ~6 km in diameter and 600 m deep, that was breached to the
W during a slope failure ~50,000 years ago. Subsequent late-Pleistocene
and Holocene eruptions from the central vent consisted of explosive
activity with pyroclastic flows accompanied by periodic lava dome growth
and destruction. A major eruption in 1660 deposited 30 cm of ash in Quito,
but most of the many eruptions since the Spanish colonial era have been
minor. The latest eruptive period began with phreatic explosions in 1998.
Magmatic eruptions first occurred in October 1999, and intermittent
eruptions of varying scale since then have blanketed Quito and surrounding
towns with ash.
Sources Instituto Geofísico http//www.epn.edu.ec/~igeo/index.html,
Washington VAAC http//www.ssd.noaa.gov/VAAC/messages.html
Guagua Pichincha Reports
http//www.volcano.si.edu/gvp/volcano/region15/ecuador/guagua/var.htm
from the Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava continued to flow down the Pulama Pali and across the coastal flat as
it has for the past 2.5 months. By the end of the week the front of the
lava flow was within 300 m of the coast. During the previous couple of
weeks, the lava flows had traveled farther E than any active flows since
1992. Overall, volcanic tremor near Pu`u `O`o was low-to-moderate and
tremor at Kilauea's caldera was low. For approximately the previous 2
weeks, small low-frequency earthquakes occurred below the caldera.
Tiltmeters in the summit area and along the E rift zone showed flat signals.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes.
Historically its eruptions originate primarily from the summit caldera or
along one of the lengthy E and SW rift zones that extend from the caldera
to the sea. The latest Kilauea eruption began in January 1983 along the E
rift zone. The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and
55th eruptive episode. Since 1986, flows have traveled 11-12 km from the
vents to the sea, paving about 80 km2 of land on the S flank of Kilauea and
building 205 hectares of new land. Intensive monitoring and field research
by staff of the US Geological Survey’s Hawaiian Volcano Observatory,
established in 1912, make Kilauea one of Earth's best studied volcanoes.
Source US Geological Survey Hawaiian Volcano Observatory
http//hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http//www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
KLIUCHEVSKOI Kamchatka Peninsula, Russia 56.06°N, 160.64°E; summit elev.
4,835 m; All times are local (= UTC + 12 hours)
The KVERT reported that during 9-15 March seismic activity was above
background levels, with interrupted spasmodic tremor and shallow
earthquakes registered. Between 1925 and 1940 on 15 March, an intense
series of shallow earthquakes were registered. Gas-and-steam plumes rose 2
km above the volcano on 12 and 14 March, and others reached 100-250 m above
the volcano on 9, 11, and 13 March. The level of Concern Color Code was
raised from Green to Yellow
http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Background. Kliuchevskoi is Kamchatka's highest and most active volcano.
Since its origin about 7,000 years ago, the beautifully symmetrical,
4,835-m-high basaltic stratovolcano has produced frequent moderate-volume
explosive and effusive eruptions without major periods of inactivity. More
than 100 flank eruptions have occurred during the past 3,000 years, mostly
on the NE and SE flanks of the conical volcano between 500 m and 3,600 m
elevation. The morphology of its 700-m-wide summit crater has been
frequently modified by historical eruptions, which have been recorded since
the late-17th century. Historical eruptions have originated primarily from
the summit crater, but have also included major explosive and effusive
events from flank craters.
Source Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Kliuchevskoi Reports
http//www.volcano.si.edu/gvp/volcano/region10/kamchat/kliuchev/var.htm
from the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
Visual and instrumental monitoring by VSI personnel revealed that volcanic
activity continued at Merapi. Hot lava avalanches continued to enter the
Sat, Senowo, Bebeng, and Lamat rivers, with a maximum runout distance of
2.5 km in the Sat River. Pyroclastic flows traveled up to 2.75 km down the
Sat, Senowo, and Bebeng rivers. Superficial earthquakes dominated the
seismicity, though fewer occurred than in the previous week. Observations
on 10 March revealed that high-pressure fumaroles appeared on most of the
dome’s surface. The volcano remained at Alert Level 2 (on a scale of 1-4).
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Source Volcanological Survey of Indonesia,
http//www.vsi.dpe.go.id/news/index.html
Merapi Reports
http//www.volcano.si.edu/gvp/volcano/region06/java/merapi/var.htm
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m
According to CENAPRED, volcanic activity that was relatively high during
14-16 March began to diminish on 17 March. On 14 and 15 March there were
many small exhalations of steam, ash, and gas, as well as episodes of
harmonic tremor that totaled 1 hour. On 15 March a new lava dome ~200 m in
diameter and 40 m high was observed at the volcano’s summit. By 17 March
fewer exhalations occurred than on previous days and harmonic tremor was
only detected for a total of 15 minutes. The volcano remained at Alert
Level Yellow Phase III, with a restricted 12-km-radius area.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava
domes have incrementally been constructed within the summit crater and
destroyed by explosive eruptions. Intermittent small-to-moderate
gas-and-ash eruptions have continued, occasionally producing ashfall in
neighboring towns and villages.
Photos (CENAPRED site) http//www.cenapred.unam.mx/boletines.html
Sources Centro Nacionale de Prevencion de Desastres,
http//www.cenapred.unam.mx/boletines.html
Washington VAAC, http//www.ssd.noaa.gov/VAAC/vaac.html
Popocatépetl Reports
http//www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html
from the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
The KVERT reported that seismicity was at background levels. On 9 and 11-14
March gas-and-steam plumes rose 400-1,000 m above the volcano. The Concern
Color Code remained at Yellow
http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large breached caldera formed by collapse of the
massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http//www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
The MVO reported that during 9-16 March activity decreased at Soufrière
Hills volcano in comparison to the previous week, with the lava dome
continuing to steadily grow. Seismic activity significantly decreased
relative to the previous few weeks. Observations confirmed that most
rockfall activity occurred to the S down the White River, with occasional
rockfalls towards the E down Tar River Valley.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that initially
forced evacuation of the southern half of the island and then destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Sources Montserrat Volcano Observatory http//www.mvomrat.com/
Soufrière Hills Reports
http//www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
During the week several small eruptions occurred at Tungurahua and seismic
activity was at high levels. Based on information from the IG, the
Washington VAAC reported that an ash emission at 1608 on 13 March produced
an ash cloud that rose to ~9.6 km a.s.l. and drifted to the NW. The IG
stated that the transmission lasted ~10 minutes and that light ash fell in
the towns of Cotalo and Pillaro. At 1415 on 15 March an eruption produced
an ash cloud that rose ~3.2 km above the volcano. An ash emission occurred
at 1756 on 16 March that rose to 8.8 km a.s.l. and drifted to the ENE.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. The volcano's
historical eruptions have been restricted to the summit crater. They have
been accompanied by strong explosions and sometimes by pyroclastic flows
and lava flows that reached populated areas at the volcano's base. The
last major eruption took place from 1916 to 1918, although minor activity
continued until 1925. The latest eruption began in October 1999 and
prompted the evacuation of the town of Baños on the N side of the volcano.
Source Instituto Geofísico, http//www.epn.edu.ec/~igeo/index.html,
Washington VAAC http//www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http//www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
*********************************************************
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
URL http//www.volcano.si.edu/gvp/usgs/
Topic 2 of 99 [Geo]: Vulcanism
Response 375 of 997: Marcia (MarciaH) * Wed, Mar 28, 2001 (15:44) * 132 lines
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Indonesia Update Report No. 607
12-18 March 2001
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From: Dan Shackelford
For the week of 12 - 18 March, Merapi continues to strongly degas from the
entire surface of the new dome, with glowing avalanches to 3km and
pyroclastic flows to 1km in length. Lokon Empung emitted white gas plumes.
Inielika showed decreased seismicity (no visual observations due to
clouds). Api Siau remained rather quiet still, thick gas plumes and red
glows were the norm, no explosions or avalanches known during this week.
Decreased shallow volcanic earthquakes at Kawah Ijen but Anak Krakatau
showed increased shallow volcanic earthquakes. Semeru was cloud-covered but
seismicity was dominated by explosion earthquakes and avalanches. No
changes at Batur whereas Soputan displayed increased seismicity and
avalanche events. Kelut showed no unusual activity.
Following is from Dali Ahmad (Volcanological Survery of Indonesia):
VOLCANIC ACTIVITY REPORTS
Information contacts: Dali Ahmad (dali@VSI.dpe.go.id)
Hetty Triastuty (hetty@VSI.dpe.go.id)
Nia Haerani (haerani@VSI.dpe.go.id)
Suswati (suswati@VSI.dpe.go.id)
VSI
Jalan Diponegoro 57 Bandung 40122
Fax : + 62 22 72 02 761
Tel: + 62 22 72 14 612
Weekly Report No. 607
2-18 March 2001
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Based on visual and instrumental monitoring Merapi activity is in
level 2. High vigilance is needed for people who work and living around
Merapi at radius 6 km from the summit.
Based on visual observations, solfatara is commonly in white thick
color, hit 575 m from the summit. Glowing lava avalanche is continuing
entered to the River Sat, Senowo, Bebeng, and Lamat, with the maximum
distance is 3 km to River Sat. Pyroclastic flow is ongoing, flowed 1 km away
to the River Sat, Senowo and Bebeng.
Superficial earthquakes are dominating the seismicity. The number and
amplitude decrease compare to the last week. Summit investigation on 17
March 2001 noticed that solfatara appear from almost of dome surface with
the high pressure and strong smell. Temperature around the summit feels hot.
There is no lahars that occurred during this week.
Merapi volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
During the week Lokon volcano often covered by clouds. From many
visual observations, white thin-medium plume is continuing appear from the
volcano hit 25-200 m above the crater rim. Seismic record since 13 March
were: 2 events of deep volcanic (A) earthquake and 19 events of tectonic
earthquake.
Lokon volcano is in level 2.
Inelika
Central Flores; 8°44' S, 120°59' E
Visual observation could not be done well because along this period
the volcano always covered by clouds. But from instrumental monitoring
Inelika activity appears decrease. During this period seismograph recorded 1
event of shallow volcanic (B) earthquake, 4 events of deep volcanic (A) and
13 events of tectonic earthquake.
Inelika volcano is in level 2.
Karangetang
Siau island; 2°47' N, 125°29' E
There was not explosion and lava avalanche that occur during the
period, and activity characterized with red-colored reflection above the
summit as height as 25 m and 50-400 m of white medium plume.
Karangetang volcano is in level 2.
Ijen
East Java;8°3.5' S, 114°14.5' E
Thick clouds covered the body of volcano during the report. Shallow
volcanic earthquakes are continuing but decrease over last week. Seismograph
recorded 27 events of shallow volcanic (B) earthquake, 3 events of small
explosion earthquake and 1 event of tectonic within this week.
Ijen volcano is in level 2.
Semeru
East Java; 8°6.50' S, 112°55' E
The summit of the volcano covered by clouds along the report, but from
seismicity record the volcano indicated an increasing in activity. Explosion
and avalanche earthquake still dominating seismicity and increase over last
week. Detail data were: 349 events of explosion earthquake, 10 events of
avalanche and 4 events of deep volcanic (A), and 3 events of tectonic
earthquake.
Semeru volcano is in level 2.
Anak Krakatau
Sunda Straits, 6°6'5.8" S, 105°25'22.3" E
Anak Krakatau showed a significant increasing within this week. It was
represents from the number of shallow volcanic earthquake which increase
compare to the week before. Detail seismiciy: 2 events of deep volcanic (A)
earthquake, 79 events of shallow volcanic (B), and 8 events of tectonic
earthquake.
Anak Krakatau is stated in level 2.
G. Soputan
North Sulawesi,124º41'12"N, 1º6'20"E
Almost the report, the Soputan edifice covered by clouds. Seismicity
record showed avalanche and tremor earthquake are ongoing and increase in
number. Seismograph recorded 12 events of tremor volcanic earthquake with
amplitude of 0.5-1 mm. Detail data listed as follow: 4 event of deep
volcanic (A) earthquake, 15 events of tectonic and 30 events of avalanche
earthquakes.
Soputan is stated in level 2.
G. Batur
Bali Island
115.37° N, 8.24° E, summit elevation 1717 m
There was no major changes from Batur volcano based on visual and
instrumental monitoring. During the report seismograph recorded 3 events of
shallow volcanic (B) earthquake, 4 events of deep volcanic (A) earthquake, 3
events of small explosion and tectonic earthquake 2 events.
Batur volcano is in level 2.
Kelut
East Java;7°56' S, 112°18.5' E
Visual and instrumental observations resulted no significant changing
in Kelut activity within the report. Seismograph recorded 2 events of
tectonic earthquake this week. Temperature measurement on 16 March 2001 is
50.2°C.
Kelut volcano is in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 376 of 997: Marcia (MarciaH) * Wed, Mar 28, 2001 (15:46) * 67 lines
*********************************
Cities on Volcanoes 2 abstracts
*********************************
From: David Johnston
Cities on Volcanoes 2 abstracts available
From the 12th to the 14th of February Auckland, New Zealand hosted the 2nd
Cities on Volcanoes conference. This well attended meeting attracted 220
registrations from over 20 countries and represented a variety of
disciplines, including Emergency Management, Physical Volcanology,
Heritage, Insurance, Education, Public Health, and Sociology.
The conference book of abstracts is now for sale - $35 (includes p&p). This
volume contains 152 abstracts and can be ordered from the Publications
Officer, Institute of Geological & Nuclear Sciences, P.O. Box 30-368, Lower
Hutt, New Zealand (fax: 64-4-570-4679), online at www.gns.cri.nz or email
sales@gns.cri.nz
(New Zealand orders in $NZ and all overseas in $US).
Cities on Volcanoes 2 T-shirts are also for sale - $20 (includes p&p).
These can be ordered from Diane Tilyard - email citiesonvolc2@gns.cri.nz
(New Zealand orders in $NZ and all overseas in $US). We accept credit cards.
*****************************************
From Magma to Tephra - paperback edition
*****************************************
From: xtracts@elsevier.nl [mailto:xtracts@elsevier.nl]
Now in PAPERBACK:
FROM MAGMA TO TEPHRA
Modelling Physical Processes of Explosive Volcanic Eruptions
Edited by
A. Freundt, GEOMAR, Forschungszentrum für Marine
Geowissenschaften, Kiel, Germany.
M. Rosi, Università di Pisa, Dipart. di Scienze della Terra,
Pisa, Italy.
Included in series Developments in Volcanology, 4
Hot MAGMA rising through the Earth's crust releases gases that
expand and may come into contact with external water that
vaporizes. The magma is then fragmented into an accelerating gas-
particle/droplet mixture that is shot into the atmosphere,
possibly in an overpressured state, where it may buoyantly rise
up into the stratosphere as an ash plume, partially or totally
collapse back to the surface, or rapidly expand sideways,
or undergo a combination of these processes.
TEPHRA is then deposited on the Earth's surface by pyroclastic
fall, flow or surge, or some hybrid mechanism. The combination of
processes that operate from the degassing of magma to the
emplacement of tephra makes an explosive volcanic eruption, and
the physical characterization of these processes is the scope of
this book.
In this book we summarize the insights into key aspects of
explosive volcanic eruptions gained from physical modelling to
date. The seven chapters are arranged in an order reflecting the
sequence from processes acting within the volcanic conduit
through dynamics of eruption and transport through the atmosphere
to mechanisms of emplacement on the Earth's surface.
For more information, reviews and a contents list, please visit:
http://www.elsevier.com/locate/isbn/0-444-82959-8
Topic 2 of 99 [Geo]: Vulcanism
Response 377 of 997: Marcia (MarciaH) * Tue, Apr 3, 2001 (12:43) * 36 lines
********************************
Piton de la Fournaise, Reunion
********************************
Piton de la fournaise 27 March 2001
After an high seimic activity since end January, a final crises started at
Piton de la Fournaise volcano today 27 March 2001 at 12h55 local time.
We recorded about 120 seismic events, the strongest beeing of magnitude 2.0.
At 13h20 a new eruption started on the ESE flanc of Piton de la Fournaise,
with 5 fissures en echelon. The final one is situated at about 1900
altitude 200 m north of the crater "Morgabim", formed during the last
October 2000 eruption.
The location on the SE flanc was suggested due to typical variations,
observed since about 2 month by two extensometers and observed before
eruption which occured in the same area in July 1999, June 2000 and October
2000.
Thomas Staudacher
Jean Louis Cheminée
==========================================
Thomas Staudacher
Observatoire Volcanologique du Piton de la Fournaise
Institut de Physique du Globe de Paris
14 RN3, le 27ème
97418 La Plaine des Cafres
La Réunion
tél.: 02 62 27 52 92
fax.: 02 62 59 12 04
********************************
Following GVP/USGS Weekly Volcanic Activity Report, 21-27 March 2001,
pictures and day to day news (in French…) about Piton de la Fournaise
current eruption on
http://www.clicanoo.com
Topic 2 of 99 [Geo]: Vulcanism
Response 378 of 997: Marcia (MarciaH) * Tue, Apr 3, 2001 (12:44) * 134 lines
*******************************
Indonesia Updates, 19-23 March
*******************************
During 19 - 23 March, Merapi's new dome continued to fume heavily with
glows, while pyroclastic flows & avalanches took place periodically. The
volcanoes Lokon-Empung, Inielika, Api Siau, Kawah Ijen, Anak Krakatau,
Soputan, Batur and Kelut remained restless but not eruptively active.
Semeru continues its decades-long eruption. Following nearly two months of
relative quiet, Lokon-Empung erupted at 1440 on 26 March, sending up an ash
cloud some 1500m. The eruption lasted approx. 1/2 hour and resulted in
local ash falls. No incandescent pyroclastics were witnessed.
Following from Dali Ahmad of the Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
VOLCANIC ACTIVITY REPORTS
Information contacts: Dali Ahmad (dali@VSI.dpe.go.id)
Hetty Triastuty (hetty@VSI.dpe.go.id)
Nia Haerani (haerani@VSI.dpe.go.id)
Suswati (suswati@VSI.dpe.go.id)
VSI
Jalan Diponegoro 57 Bandung 40122
Fax : + 62 22 72 02 761
Tel: + 62 22 721 46 12
Weekly Report No. 608
19-23 March 2001
Merapi
Central Java; 7°32.5' S, 110°26.5' E
450 m white solfatara is continuing appear from the summit, was
observed from Ngepos observatory on 22 March 2001 08.15 WIB. Night
observations from Ngepos, Jrakah, Babadan and Kaliurang observatory noticed
red-colored reflection around lava dome. During the week observer reported 4
events of pyroclastic flows travelled 2 km to Sat river and 2.75 km of lava
avalanches. Observer did not reported a changing about lava dome 2001.
Furthermore, seismicity dominated with avalanche earthquakes.
Merapi volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
25-200 m of white thin-medium solfatara is continuing, but in general
Lokon activity looks decrease compare to the previous week. Seismograph
recorded 13 events of tectonic earthquake within the report.
Lokon volcano is in level 2.
Inelika
Central Flores; 8°44' S, 120°59' E
Visual observation obscured by the haze during the week. Instrumental
monitoring from seismograph showed 3 events of deep volcanic (A) and 9
events of tectonic earthquake.
Inelika volcano is in level 2.
Karangetang
Siau island; 2°47' N, 125°29' E
Observation to the volcano could not be done because the weather was
cloudy during the report, while seismograph is in repairing.
Karangetang volcano is in level 2.
Ijen
East Java;8°3.5' S, 114°14.5' E
Volcano edifice covered by clouds within the week. Monitoring to the
volcano based on seismograph noticed 12 events of shallow volcanic (B) and 4
events of small explosion earthquake, less than previous data.
Ijen volcano is in level 2.
Semeru
East Java; 8°6.50' S, 112°55' E
Although high in number, seismic activity on Semeru showed a
significant decreasing. Complete data listed as follow: 2 events of deep
volcanic (A), 259 events of explosion and 1 event of tectonic earthquake.
Semeru volcano is in level 2.
Anak Krakatau
Sunda Straits, 6°6'5.8" S, 105°25'22.3" E
After showed an increasing activity last week, within this week Anak
Krakatau showed decrease again. That was represents from the number of
seismicity which lees than previous data. Detail seismicity were: 34 events
of shallow volcanic (B) and 1 event of tectonic earthquake.
Anak Krakatau is stated in level 2.
G. Soputan
North Sulawesi,124º41'12"N, 1º6'20"E
There was no major change in Soputan activity based on visual and
instrumental observation. Almost the week, visual observation obscured by
clouds. 0.5-2 mm uncontinuous tremor is continuing. Seismograph also
recorded other seismicity, were: 5 event of deep volcanic (A) earthquake, 1
event of shallow volcanic (B), 18 events of tectonic and 56 events of
avalanche earthquakes.
Soputan is stated in level 2.
G. Batur
Bali Island
115.37° N, 8.24° E, summit elevation 1717 m
Batur volcano seems quiet. Both from visual and instrumental
monitoring no significant activity has reported. White thin plume appear
from crater rose 10 m height. Seismograph noticed 1 event of shallow
volcanic (B) earthquake and tectonic earthquake 10 events.
Batur volcano is in level 2.
Kelut
East Java;7°56' S, 112°18.5' E
Visual and instrumental observations resulted no significant changing
in Kelut activity within the report. Seismograph recorded 2 events of
tectonic earthquake this week. Temperature measurement on 16 March 2001 is
50.2°C.
Kelut volcano is in level 2.
******************************
Lokon-Empung Update, 26 March
26 March Ash Explosion on Lokon Volcano
Lokon volcano is situated at North Sulawesi at 1°21.5' N, 124°47.5' E
and summit elevation is 1784 m.
After 28 January 2001 explosion, Lokon activity is continuing up to
now and exploded again on 26 March 2001.
On 26 March, 2001 at 14.40 WITA (local time) Lokon volcano exploded.
Dark ash rose 1500 m above crater rim. Ash drifted east and northward.
Explosion did not produce any glowing materials. 25 minutes after explosion,
ash started to fall at Kinilow village (3.5 km from the crater) and
Kakaskasen village (4 km from the crater).
Explosion getting slow down and at 15.10 local time, white thick gas
emission observed from the crater, rose 400 m height.
Ash fall has thickness of 0.3-0.5 cm at Kinilow village, 0.1-0.3 cm at
Kakaskasen village, 1-2 cm around Pasahapen river, about 1 km from crater.
After explosion activity, tremor volcanic recorded between 14.42 until
14.57 local time, which has maximum amplitude of 2-16 mm. Seismograph
recorded 13 events of deep volcanic (A) and 12 events of shallow volcanic
(B) on 25 March and on 26 March recorded 6 events of deep volcanic (A) and 7
events of shallow volcanic (B) earthquake.
Topic 2 of 99 [Geo]: Vulcanism
Response 379 of 997: Marcia (MarciaH) * Fri, Apr 6, 2001 (15:43) * 79 lines
Volcano Watch - April 5, 2001 - Kilauea's all cracked up, and that's not funny
Late on March 30, a visiting geology student from Oregon fell about
12 m (40 feet) into a crack in the ground between Crater Rim Drive and the
rim of Kilauea's caldera, opposite Kilauea Military Camp. He and a
companion had seen a dark area free of vegetation. Lacking a flashlight,
they couldn't tell what it was. After some discussion, they went for it.
The man fell. The young woman stopped in time, hurried back to the road,
left a slipper to mark the location, and ran screaming to KMC for help.
Paramedics quickly responded and worked with a rescue team from the
national park and Hawai`i County to pull the man to safety. He had ended up
on a narrow ledge, which kept him from falling much farther, and luckily
escaped with minor though numerous contusions.
Encounters with cracks in the summit area of Kilauea are not new. Two
members of Ellis` exploring party fell into cracks on Steaming Flat near
Sulphur Bank on August 1, 1823, though fortunately none was badly injured.
They had more of an excuse than do most later victims, however. Many cracks
were then covered by a thin veneer of volcanic ash erupted in and before
1790. Now more of the cracks are open and obvious, because the veneer has
washed away.
How do the cracks form? Most in the summit area result from the
collapse of the caldera in the late 15th century. They formed when the
caldera dropped down and the walls of the new depression moved slightly
toward the empty space. Similar kinds of cracks develop behind blasted
quarry faces.
Some of the cracks are actually small faults that formed during the
collapse of the caldera. They can be recognized by vertical offset, the
side nearest the caldera being a little lower than the other side.
Other cracks form during landslides or rockfalls into the caldera.
The 1983 Ka`oiki earthquake caused large rock slides that peeled away from
the northeast side of the caldera, damaging Crater Rim Drive beyond repair.
The Earthquake Trail, starting near Volcano House, now takes visitors along
the old pavement to the site of the slides, where hikers can note gaping
cracks cutting the pavement.
All of these cracks are more or less concentric to the caldera. Their
consistent pattern, paralleling the wall of the caldera, helps to recognize
them and to anticipate where one can step safely to avoid them.
Away from the high ground, some cracks on the caldera floor are also
concentric. Most are near Halemaumau and formed during the 1924 collapse of
the crater or during later rock falls. Many of these cracks are very
dangerous and are to be avoided at all cost.
Other cracks on the floor are straight, not curved, and are related
to eruptions. Most of these cracks trend a little north of due east.
Several can be seen northeast of Halemaumau, in the area of eruptions in
1954, 1971, and 1982.
Still other cracks on the caldera floor are related to the collapse
of the caldera itself. Some of these cracks have been reactivated from time
to time. A good example is the crack that crosses the road just beyond the
southeast end of the Halemaumau parking lot. It reopened in 1924, though
its trend shows it to be a caldera fault that formed much earlier.
Cracks are common in the summit area of Kilauea. Many visitors are
surprised by them. The crack hazards are easily avoided. Stay on trails,
don't walk after dark without a flashlight, and don't wander around
outdoors if you're under the influence.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week and provided visitors with an occasional
glimpse of surface flow activity on Pulama pali and on the coastal flats.
Lava is pooling in the coastal flats and not entering the ocean at this
time. The amoeba-like flow activity in the coastal flats has advance the
sluggish front to within 400 m (1,300 ft) of the sea coast in the old
Kupapa`u area near the eastern boundary of Hawai`i Volcanoes National Park.
Two earthquakes were reported felt by a resident of Aloha Estates
subdivision during the week ending on April 5. Both earthquakes were felt
on Monday, April 2 by the Glenwood resident. The first earthquake at 1:10
a.m. was located 15 km (9.0 mi) southeast of the summit of Kilauea Volcano
at a depth of 1.25 km (0.75 mi). The second earthquake at 8:52 a.m. was
located 6 km (3.6 mi) north of the summit of Kilauea Volcano at a depth of
24 km (14.4 mi). The two felt earthquakes had magnitudes of 3.0 and 3.2,
respectively.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
Topic 2 of 99 [Geo]: Vulcanism
Response 380 of 997: Marcia (MarciaH) * Tue, Apr 10, 2001 (19:06) * 534 lines
Smithsonian Institution
Bulletin of the Global Volcanism Network
Volume 25, Number 2, February 2001
Editors: Rick Wunderman and Ed Venzke
Editorial Assistants: Gari Mayberry, Luke Jensen, David Charvonia, and
Jacquelyn Gluck
#####
McDonald Islands (Indian Ocean) Emission of volatiles on 9 November 2000;
morphological changes
Heard (Indian Ocean) Increased fumarolic activity in February and March
2001; possible lava flow
Kelut (Indonesia) Changes in water temperature, surface level, and pH
detected in crater lake
Kerinci (Indonesia) Gas and steam plumes and explosion earthquakes, February
to mid-October 2000
Ambrym (Vanuatu) Visits during 1999 and 2000 revealed variable lava lake
and explosive activity
Suwanosejima (Japan) Two subsidiary craters discovered; elevated activity
in December 2000
Miyakejima (Japan) Continued high SO2 flux; volcanic tremor and eruption
occur in mid-March
Fuji (Japan) September 2000-January 2001 swarm includes M £ 2.2 earthquakes
but lacks geodetic changes
Soufriere Hills (Montserrat) Dome growth, rockfalls, and pyroclastic flow
continue through March 2001
McDonald Islands
Indian Ocean
53.03 S, 72.60 E; summit elev. 186 m
Observations of McDonald Island were made from aboard the vessel “RSV
Aurora Australis” on 9 November 2000. These were the first documented
observations of the volcano in several months. Atmospheric conditions were
overcast but afforded good lateral visibility. Venting of volatiles was
first sighted at a distance of 24 km from the island. Subsequent
observations were made as close as 7 km offshore. Dispersed activity was
visible at several points high on the flanks of the island. On the NE side,
fumarolic activity was most pronounced at the top of a short steep gully
extending below the apparent summit crater. Pulses of emission produced
plumes 30-50 m high from this point every few minutes. Volatiles were also
being emitted from several other points on the NW slopes, and at the N end
of the island where they originated at the foot of rock bluffs near the top
of the coastal slope and at another location on the slope at ~60 m
elevation. There was no evidence of activity on the S portion of the island.
The emissions observed during November 2000 were less pronounced than those
described on 13 January 1999 (Bulletin v. 24, no. 1). They also appear to
have been issuing from higher on the slopes than those observed on 18 March
and 2 April 1997 (Bulletin v. 23, no. 2). The position of the most forceful
emissions observed during November 2000 appeared identical to those first
seen in March 1997. Significant emissions from the face below the crater at
~70 m elevation, and from two points at the head of an apron of
dark-colored rubble a few hundred meters N of the gully extending from the
summit crater, were also similar to those of 1997. Weak discharges that
rose from the N edge of the apron were detectable to ~80 m elevation during
November 2000, but were absent during March 1997. No steaming ground was
observed below ~60-70 m elevation during November 2000, nor was there any
evidence of fumarolic activity at sea level as had been cited during March
1997.
Comparisons of color vertical air photographs taken in 1980 from 3,050 m,
1,650 m, and 980 m altitudes to oblique photographs taken from sea level
aboard the "RSV Aurora Australis" on 18 March 1997 and 9 November 2000
(figure 1) indicate that the most significant changes to the morphology of
the volcano occurred prior to the vessel's first visit. Some steep coastal
slopes appeared to have been replaced by slopes of more moderate angle. A
more jagged skyline of bare rock has replaced the relatively smooth,
vegetated upper slopes that previously existed.
Figure 1. General view of the NE coast of McDonald Island under hazy
conditions on 9 November 2000. Photo by Graeme Snow (AAD), courtesy of
Kevin Kiernan.
Background. Three small, low islands on the Kerguelen Plateau form the
McDonald Islands. The largest island, McDonald, has an area of 1 km^2 and
is composed of a layered phonolitic tuff plateau cut by phonolitic dikes
and lava domes. Some general references on McDonald Island include
Collerson and others (1998); Kiernan and McConnell (1999); and Quilty and
Wheller (2000). A nearby active submarine eruption was inferred from
phonolitic pumice that washed up on Heard Island in 1992; this marked the
first historical activity at McDonald. Volcanic plumes from McDonald Island
were observed in December 1996 and January 1997.
References: Collerson, K.D., Regelous, M., Frankland, R., Wendt, J.I.,
Kiernan, K., and Wheller, G., 1998, 1997 eruption of McDonald Island
(southern Indian Ocean): new trace element and Th-Sr-Nd isotopic
constraints on Heard-McDonald magmatism: Abstracts, 14th Australian
Geological Convention, Townsville, July 1998.
Kiernan, K., and McConnell, A., 1999, Geomorphology of the Sub-Antarctic
Australian Territory of Heard Island-McDonald Island: Australian
Geographer, v. 30, no. 2, p. 159-195.
Quilty, P.G., and Wheller, G., 2000, Heard Island and the McDonald Islands:
A window on the Kerguelen Plateau: Papers & Proceedings of the Royal
Society of Tasmania, v. 133, no. 2, p. 1-12.
Information Contacts: Suzanne Stallman, Gordon Bain, and Graeme Snow,
Australian Antarctic Division (AAD), Channel Highway, Kingston, TAS 7050,
Australia (URL: http://www.antdiv.gov.au/; Email:
Suzanne.Stallman@aad.gov.au, Gordon.Bain@aad.gov.au, Graeme.
Snow@aad.gov.au); Kevin Kiernan and Anne McConnell, Geography &
Environmental Studies, University of Tasmania, GPO Box 252-79, Hobart TAS
7001, Australia (URL: http://www.geol.utas.edu.au/geog/; Email: kevink@
fpb.tas.gov.au, annemc@aaa.net.gov.au).
Heard
Indian Ocean
53.106 S, 73.513 E; summit elev. 2,745 m
All times are local (= UTC + 7 hours)
Fumarolic activity emanating from Big Ben stratovolcano on Heard Island
increased since the previous report period of October-November 2000
(Bulletin v. 25, no. 11). Both the vent at the summit of Mawson Peak and
the second, recently confirmed vent downslope from the summit, were
involved in the activity in early February 2001.
At about 2100 on 2 February an increased emission of volatiles was observed
from Atlas Cove, located ~15 km NW of the summit where the main island
connects with the Laurens Peninsula (see maps in Bulletin v. 10, no. 2 and
v. 23, no. 2). Under daylight the plume had a yellow-colored tinge. By
midnight venting increased substantially. Observations continued until 0100
on 3 February when emissions appeared to diminish and clouds obscured the
view. No lava or ejecta were observed from the Atlas Cove vantage point.
The plumes rose up to ~1,000 m in height, but tended to vary in extent over
time. The precise points of emission were hidden by the high shoulder of
Big Ben. Nevertheless, the emissions appeared to emanate from two discrete
vents, one at Mawson Peak, and the other the newly discovered vent
estimated to be 300-400 m vertically below it (lower than previously
thought) on the S-facing slope.
Observations on the afternoon of 3 February revealed further abatement of
volatile venting. Some workers suggested the presence of a third vent based
on observations from Anzac Peak on Laurens Peninsula at the NW end of the
island, but these findings are not yet substantiated. From a high point on
Laurens Peninsula a black lava flow (?) on Mawson Peak was observed to be
closer to the Atlas Cove side of the island than on previous visits. The
possible flow was ~100 m wide and ~1,500 m long, but size estimates were
hindered by distance, the enormity of Big Ben, the lack of any comparative
scale, and the acute viewing angle.
On 5 March observers obtained good views of Big Ben from Red Island, at the
farthest N tip of the Laurens Peninsula, but were unable to discern any
summit activity despite clear conditions. Further observations from the
same vantage point at 1330 on 7 March afforded a brief 5-8 minute view of
the summit and revealed that a significant plume rose 100-200 m and drifted
several kilometers downwind. The plume's width was estimated to be 50 m.
The "black scar" first viewed on 3 February and interpreted as a plausible
lava flow was again visible and appeared unchanged since its last observation.
The findings in early February and March 2001 are consistent with recent
observations during a helicopter overflight of Big Ben that confirmed the
presence of a vent well below the summit of Mawson Peak (Kiernan &
McConnell, 2000). They compound the likelihood that more than one vent was
involved in earlier eruptive activity during 1950-52 and 1985 (ANARE
Station Reports; Neumann van Padang, 1963), contrary to recent conclusions
by Quilty & Wheller (2000). Observations of volcanism on Heard Island,
however, are limited because of its remoteness, and since the summit area
is frequently shrouded in clouds. Hence, the general level of activity
observed recently is difficult to assess.
Background. Heard Island on the Kerguelen Plateau in the southern Indian
Ocean consists primarily of the emergent portion of two volcanic
structures. The large glacier-covered composite cone of Big Ben comprises
most of the island, and the smaller Mt. Dixon volcano lies at the NW tip of
the island across a narrow isthmus. Little is known about the structure of
Big Ben volcano because of its extensive ice cover. The historically active
Mawson Peak forms the island’s high point and lies within a 5-6 km wide
caldera breached to the SW side of Big Ben. Small satellitic scoria cones
are located mostly on the N coast. Several subglacial eruptions have been
reported in historical time. The remote island volcano is uninhabited, but
includes an infrequently occupied base operated by the ANARE.
References: Kiernan, K., and McConnell, A., 2000, ASAC Project 1118,
Geomorphological Evolution of Heard Island: Report to Atlas Cove Station
Leader, ANARE.
Neumann van Padang, M., 1963, Arabia and the Indian Ocean: Catalogue of the
Active Volcanoes of the World, v. 16, p. 1-64.
Quilty, P.G., and Wheller, G., 2000, Heard Island and the McDonald Islands:
A window on the Kerguelen Plateau: Papers & Proceedings of the Royal
Society of Tasmania, v. 133, no. 2, p. 1-12.
Information Contacts: Stu Fitch and Andrew Lock, Australian Antarctic
Division, Channel Highway, Kingston, TAS 7050, Australia (URL:
http://www.antdiv.gov. au/; Email: stuart.fitch@afma.gov.au, Andrew_Lock@
aad.gov.au); C.J. Klok, Department of Zoology and Entomology, University of
Pretoria, Pretoria 0002, South Africa (URL:
http://www.up.ac.za/academic/zoology/; Email: cjklok@zoology.up.ac.za);
Kevin Kiernan and Anne McConnell, Geography & Environmental Studies,
University of Tasmania, GPO Box 252-79, Hobart TAS 7001, Australia (URL:
http://www.geol.utas.edu.au/geog/; Email: kevink@fpb.tas.gov.au,
annemc@aaa.net.au).
Kelut
Java, Indonesia
7.93 S, 112.31 E; summit elev. 1,731 m
Monitoring of Kelut's crater lake indicated a relative increase of water
temperature, a rise in surface level, and a decrease in pH into late
February 2001. The Volcanological Survey of Indonesia (VSI) released new
information revealing that temperatures actually began to rise as of 8
January 2001, rather than on 19 February as disclosed in a previous report
(Bulletin v. 25, no. 12). The lake reached a maximum temperature of 51.2
deg C on 30 January (table 1).
Table 1. Crater lake temperatures during 8 January-26 February 2001 and pH
during November 2000February 2001. The maximum temperature increase was
12.7°C, while the overall increase for the period was 9.3°C. In contrast,
pH decreased. Courtesy of VSI.
Date Water Temperature pH
Nov 2000 6.9
Jan 2001 6.3
08 Jan 2001 38.5
18 Jan 2001 47.5
19 Jan 2001 49.1
29 Jan 2001 50.1
30 Jan 2001 51.2
02 Feb 2001 50.1
07 Feb 2001 51.0 5.0
13-19 Feb 2001 47.5 5.3
20-26 Feb 2001 47.8 5.3
A 60-cm increase in lake water level was observed as of 19 January relative
to the height at an undisclosed earlier date. Workers measured pH values of
the crater lake water and detected a significant overall decrease in pH, or
an increase in acidity (table 1). VSI maintained a hazard status of 2 (on a
scale of 1-4) since 19 January 2001.
Background. Although relatively small and infrequently reported on, Kelut
has produced some of Indonesia’s most deadly eruptions. There have been 10
fatal crater lake eruptions, and an estimated 10,000 people died in lahars
in 1586. Drainage tunnels engineered to control the lake level have greatly
reduced the destructive impact of recent eruptions. Kelut’s 1000 AD
eruption is the oldest historically recorded in Indonesia.
Information Contact: Dali Ahmad, Volcanological Survey of Indonesia (VSI),
Jalan Diponegoro No. 57, Bandung 40122, Indonesia (Email:
dali@vsi.dpe.go.id; URL: http://www.vsi.dpe.go.id).
Kerinci
Sumatra, Indonesia
1.69 S, 101.27 E; summit elev. 3,805 m
Persistent fumarolic activity occurred at Kerinci during February to
mid-October 2000. During the report period Kerinci mainly produced
light-colored, variably dense gas-and-steam plumes that rose 50-600 m.
Plumes were occasionally reported to darken and become dense between 29
February and 20 March, possibly indicating ash emission, although no
ashfall was reported. Small explosion earthquakes, usually related to gas
discharge, dominated seismicity throughout the interval with an average of
~240 events recorded per week. These earthquakes were continuous during
late April to mid-May. Consistent numbers of deep volcanic (A-type),
shallow volcanic (B-type), and tectonic earthquakes occurred throughout the
period. During the report interval no major eruptions were observed, and
Kerinci's hazard status did not exceed 2 (on a scale of 1-4).
Background. The summit of Kerinci, Indonesia's highest volcano, contains a
deep 600-m-wide crater often partially filled by a small crater lake. The
volcano is also known as Gadang, Berapi Kurinci, Korinci, or Peak of
Indrapura. The massive 13 x 25 km wide volcano towers 2,400-3,300 m above
surrounding plains. Kerinci is elongated in a N-S direction and is capped
by an unvegetated, young summit cone constructed NE of an older crater
remnant. One of Sumatra’s most active volcanoes, Gunung Kerinci has
produced a series of moderate explosive eruptions during the 19th and 20th
centuries. Usually, the crater of Kerinci is filled with green to yellow
water. In March 1934 the crater drained but a lake returned in February
1937. Phreatic explosions from the summit crater are reported almost
annually from the Kayu Aro tea estate on the S flank. The surrounding
region is sparsely populated.
Information Contact: Dali Ahmad, Volcanological Survey of Indonesia (VSI),
Jalan Diponegoro No. 57, Bandung 40122, Indonesia (Email:
dali@vsi.dpe.go.id; URL: http://www.vsi.dpe.go.id).
Ambrym
Ambrym Island, Vanuatu
16.25 S, 168.12 E; summit elev. 1,334 m
All times are local (= UTC + 11 hours)
The following report discusses observations of Marum and Benbow craters (in
the central and WSW portions of Ambrym's caldera, respectively). The
observations were made in September-October 1999 and August-October 2000.
Our previous Ambrym report discussed aerial observations made in late
February 2000 (Bulletin v. 25, no. 4). Marum and Benbow host long-standing
lava lakes with active surfaces (sometimes molten and sometimes chilled).
1999 Marum observations. On 24 September 1999 the lava lake was once again
present at more or less the normal site. It measured ~60 m in diameter and
underwent significant degassing accompanied by turbulent waves and the
escape of incandescent fragments. On several occasions, observers witnessed
large collapses on the periphery as well as rapid and sudden variations in
the lake’s surface level. At the foot of the SE face, perhaps three
explosive vents ejected plumes of ash and cauliflower-shaped discharges of
steam at irregular intervals varying from 8 to 30 minutes. At night,
observers distinguished incandescence along concentric faults on the lava lake.
On 22 October 1999 observers camped on the crater's edge, on the
ash-covered floor found to its ESE. They noted that the main lava lake had
grown since September, and it displayed more violent, regular degassing.
Its surface was continuously disrupted by waves and escaping incandescent
fragments that rained all the way down the active terrace. Observers saw a
second small elongate lake and reported that its surface too was sometimes
very agitated. At night, several incandescent faults were seen on the
bottom of the terrace. These spread open and then closed, indicating that
the entire zone had a thin, partially solidified crust.
On 23 October bad weather prevented visual observations, but at night
observers saw intense red glow, felt tremors, and heard rumblings. On 24
October, at sunrise, the meteorological conditions were excellent, but
volcanic gas obscured the crater.
1999 Benbow observations. On 23 September 1999, observers looking toward
Benbow crater from the sea saw a large column of ash and gas rising about
1,200 m above the crater. On two occasions at night, visitors saw brief
instances of weak incandescence in the plume’s interior.
A month later, on 23 October 1999, despite unstable weather conditions,
observers reached summit crests and saw gas occupying the crater's
interior. They saw the first terrace only for a brief moment and then only
partially, making it impossible to say whether the lava lake was again
molten at the surface. The characteristic rumblings that accompanied the
regular degassing on the lake's surface were perceptible but weak, as if
molten material lay beneath a thin chilled surface.
2000 Marum observations. During the nights of 2 and 3 August 2000 a lava
lake was clearly visible (about 100 x 60 m in size). Regular and sustained
degassing agitated the surface with big waves. Showers of incandescent
fragments rose to heights of ~50-70 m.
On the night of 16 August a tropical depression crossed the region
affecting an area extending at least as far as the Banks Islands ~200 km N.
Heavy rains fell on the Marum plateau. Thick "smoke" rose from the crater,
impeding visual observations.
On the night of 30 September-1 October, incessant rain again fell on the
Marum plateau. Very poor visibility in the crater stopped for a few minutes
around 0100, enabling observers to confirm the absence of the lava lake’s
exposed molten surface. At that time, only two small and closely spaced
circular vents emitted incandescent gases.
2000 Benbow observations. Observers descended to the first terrace level on
3 August 2000, crossing along the crests that encircled the central shaft.
At this time, there was no exposed molten lava on the lake's surface.
Still, violent and continuous explosions fed a darkly colored, dense ash
plume. These outbursts came from a vent situated in the deepest part of the
central opening. The excursion failed to get around the NE vent on the
terrace level N1 due to a zone of mass wasting that left a scar ~160 m
deep. On 17 August, torrential rains and excessively violent winds impeded
attempts to approach Benbow.
On 1 September, people descending to terrace N1 felt sub-continuous tremor
but found comparatively little gas. What gas there was looked blue in color
and hung over the central opening. The lava lake was once again present
(but difficult to see due to impeded access caused by the above-mentioned
scar). Degassing accompanied by rumblings and strong detonations sent
incandescent lava fragments to heights of ~100 m.
Background. Ambrym, a large basaltic volcano with a 12-km-wide caldera, is
one of the most active volcanoes of the New Hebrides arc. A thick, almost
exclusively pyroclastic sequence, initially dacitic, then basaltic,
overlies lava flows of a pre-caldera shield volcano. The caldera was formed
during a major Plinian eruption with dacitic pyroclastic flows about 1900
years ago. Post-caldera eruptions, primarily from Marum and Benbow cones,
have partially filled the caldera floor and produced lava flows that ponded
on the caldera floor or overflowed through gaps in the caldera rim.
Post-caldera eruptions have also formed a series of scoria cones and maars
along a fissure system oriented ENE-WSW. Eruptions have apparently occurred
almost yearly during historical time from cones within the caldera or from
flank vents. However, from 1850 to 1950, reporting was limited mostly to
extra-caldera eruptions that would have affected local populations.
Information Contact: G. de St. Cyr, c/o Bulletin of the Geneva Society of
Volcanology, C.P. 6423, CH-1211, Geneva 6, Switzerland (Email:
svg@worldcom.ch).
Suwanose-jima
Ryukyu Islands, Japan
29.53 N, 129.72 E; summit elev. 799 m
All times are local (= UTC - 9 hours)
An observer on Suwanose-jima reported seeing "smoke" rise from NE of the
summit crater at about 1700 on 19 December 2000. The following day,
Kazuhiro Ishihara from Sakura-jima Volcano Research Center (SVRC, formerly
Sakura-jima Volcano Observatory, SVO) of Kyoto University inspected the
crater area during a helicopter flyover. He observed an ash-laden,
high-temperature gas emission from the main active crater, On-take, and
from two newly formed craters on the outer NE slope of the main crater
(figures 2 and 3).
Figure 2. Topographic map of Suwanosejima illustrating the main active
crater (1), Ontake, and the newly discovered craters (2, 3). Thick textured
lines are crater rims. Contour interval is 100 m. After a map by SVRC.
Figure 3. Photo of the NE slope of Suwanosejima showing the main active
crater (1), Ontake, and two subsidiary craters (2, 3). Courtesy of SVRC.
Subsequent observations on 24 December by Masato Iguchi and Daisuke Miki,
both of SVRC, revealed more about the nature of the craters' activities.
Craters 2 and 3 were ~40 m and ~200 m away from the main crater rim,
respectively. Crater 2 had a diameter of ~25 m, and crater 3 had a diameter
of ~10 m. The craters were thermally surveyed from a helicopter. On-take
(crater 1) had a temperature of ~450 deg C, and emitted light-colored
vapor. Crater 2 released an ash-laden plume and had a temperature of ~100
deg C. Crater 3, which had a temperature of ~270 deg C, ejected gas and a
small amount of ash.
Seismicity recorded by SVRC showed that ~10 deep volcanic (A-type)
earthquakes occurred monthly, an increase since fall 1999. Shallow volcanic
(B-type) earthquakes had also increased since early 2000 with the
occurrence of ~50-300 events monthly. Researchers using GPS techniques
discovered that deformation had increased the distance between
Suwanose-jima and Nakano-shima, a neighboring island, by 1 cm. SVRC
indicated that activity was elevated, but that it did not imply an
immediate large-scale eruption.
Background. The 8-km-long, spindle-shaped island of Suwanose-jima is
occupied by a stratovolcano with two historically active summit craters.
The volcano is one of the most active in Japan. Only about 50 persons live
on the sparsely populated island. The summit of the volcano is truncated by
a large breached crater. The breach opens and extends to the sea on the E
flank; it was formed by edifice collapse. Intermittent Strombolian
eruptions have taken place from On-take, the NE summit crater. The largest
historical eruption took place in 1813-14, when thick scoria deposits
blanketed residential areas, after which the island was uninhabited for
about 70 years. The SW crater produced lava flows that reached the W coast
in 1813, and lava flows reached the E coast of the island in 1884.
Information Contacts: Disaster Prevention Research Institute, Kyoto
University (URL: http://www.dpri. kyoto-u.ac.jp/); Setsuya Nakada and
Hidefumi Watanabe, Volcano Research Center, Earthquake Research Institute,
University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan (URL:
http://hakone.eri.u-tokyo. ac.jp/vrc/VRC.html; Email:
nakada@eri.u-tokyo.ac.jp, kaneko@eri.u-tokyo.ac.jp).
Miyake-jima
Izu Islands, Japan
34.08 N, 139.53 E; summit elev. 815 m
Activity since October 2000 (Bulletin v. 25, no. 9) through 12 February
2001 has been characterized by high volumes of volcanic gas emission. Minor
ashfall was reported only near the summit crater. The active crater's
temperature increased to 400 deg C during late December 2000; slight
incandescence of the crater was observed at night, but disappeared by late
January 2001. Ground deformation of Miyake-jima, which began in July 2000,
declined, but still continued. Seismicity was low during September
2000-early February 2001, although shallow low-frequency earthquakes
occurred in late January.
During October 2000-early February 2001 the plume that rose from
Miyake-jima varied in height from several hundred meters to as much as two
thousand meters. The SO2 flux maintained high values in the range of
~18,000-45,000 metric tons/day during the period. An abundance of the gas
was often observed around the volcano's flanks depending on weather
conditions. As of early February 2001, there was no indication of any
decrease in the SO2 flux.
On 16 March 2001 the largest volcanic tremor episode since 29 August 2000
was recorded at Miyake-jima. Three days later, on 19 March, an eruption
produced a black ash cloud that rose 800 m above the volcano. The island
has remained uninhabited since 1 September 2000 when officials ordered an
evacuation due to the persistent volcanic activity that began on 26-27 June
2000 (Bulletin v. 25, no. 5).
Background. The circular, 8-km-wide island of Miyake-jima forms a low-angle
stratovolcano with a 3-km-wide summit caldera partially filled by the
summit cone Oyama (many reports call the volcano Oyama). Parasitic craters
and vents, including maars near the coast and radially oriented fissure
vents, dot the volcano. Frequent historical eruptions have originated at
vents ranging from the summit to sea level, causing much damage. A
significant eruption of Miyake-jima occurred in 1983 that forced ~4,000
residents to evacuate the island. There were no injuries or fatalities
reported then, but basaltic lava flows destroyed 80% of the W-flank town of
Ako and reached the sea on the SW coast.
Information Contacts: Setsuya Nakada and Hidefumi Watanabe, Volcano
Research Center, Earthquake Research Institute, University of Tokyo, Yayoi
1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan (URL:
http://hakone.eri.u-tokyo.ac.jp/vrc/VRC.html; Email:
nakada@eri.u-tokyo.ac.jp, kaneko@eri.u-tokyo.ac.jp); Japan Meteorological
Agency, Volcanological Division, 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100,
Japan (URL: http://www.kishou.go.jp/english/); Kyodo News Agency (URL:
http://home.kyodo.co.jp/).
Fuji
Honshu, Japan
35.35 N, 138.73 E; summit elev. 3,776 m
According to the Japan Meteorological Agency (JMA), a relatively large
number of low-frequency, low-magnitude earthquakes have occurred at ~15 km
depth below Fuji volcano since September 2000 (table 2, figure 4). For
comparison, during recent years before this spike, the number of
earthquakes had averaged only 1-2 per month. The maximum earthquake
magnitude during September 2000-January 2001 was M 2.2, recorded on 11
October. During November-December earthquakes with M greater than 2.0 occurred 7
times. Earthquake hypocenters were generally located below an area NE of
the summit. Geodetic parameters measured by GPS, EDM, and tilt-meters did
not escalate. Located 150 km W of Tokyo, Fuji's close proximity encouraged
the installation of enhanced instrumentation in order to better monitor the
volcano. Previous seismic swarms at Fuji in 1987 and 1996 (Bulletin v. 12,
no. 8 and v. 21, no. 2) had lower event counts than the current episode.
Table 2. Seismic events registered at Fuji during September 2000-January
2001. Data courtesy of JMA and Reuters.
Month Seismic Events
Sep 2000 35
Oct 2000 133
Nov 2000 222
Dec 2000 144
Jan 2001 36
Figure 4. Latitude, longitude, depth, and magnitude of seismicity at Fuji
during September 2000February 2001. Earthquake crosssections are shown in
NS (upper right) and EW (bottom) planes. Figure by Shinichi Sakai; courtesy
of Setsuya Nakada (VRCERI).
Topic 2 of 99 [Geo]: Vulcanism
Response 381 of 997: Marcia (MarciaH) * Tue, Apr 10, 2001 (19:08) * 248 lines
Background. The conical form of Fuji-san, Japan's highest and most noted
volcano, belies its complex origin. The modern postglacial stratovolcano is
constructed above a group of overlapping volcanoes, remnants of which form
irregularities on Fuji's profile. Growth of the Younger Fuji volcano began
with a period of voluminous lava flows from 11,000 to 8000 years before
present (BP), accounting for four-fifths of the volume of the Younger Fuji
volcano. Minor explosive eruptions dominated activity from 8000 to 4500 BP,
with another period of major lava flows occurring from 4500 to 3000 BP.
Subsequently, intermittent major explosive eruptions occurred, with
subordinate lava flows and small pyroclastic flows. Summit eruptions
dominated from 3000 to 2000 BP, after which flank vents were active. The
extensive basaltic lava flows from the summit and some of the more than 100
flank cones and vents blocked drainages against the Tertiary Misaka
Mountains on the N side of the volcano, forming the Fuji Five Lakes,
popular resort destinations. The last eruption of this dominantly basaltic
volcano in 1707 was Fuji's largest during historical time; it deposited ash
on Edo (Tokyo) and formed a large new crater on the E flank.
Information Contacts: National Research Institute for Earth Science and
Disaster Prevention, 3-1, Tennodai, Tsukuba-shi, Ibaraki-ken, 305, Japan
(URL: http://www.bosai.go.jp/); Setsuya Nakada, Hidefumi Watanabe, and
Shin-ichi Sakai, Volcano Research Center, Earthquake Research Institute,
University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan (URL:
http://hakone.eri.u-tokyo.ac.jp/vrc/VRC.html; Email:
nakada@eri.u-tokyo.ac.jp, kaneko@eri.u-tokyo.ac.jp,
coco@eri.u-tokyo.ac.jp); Japan Meteorological Agency, Volcanological
Division, 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan (URL:
http://www.kishou.go.jp/english/); Reuters (URL: http://www.reuters.com/).
Soufriere Hills
Montserrat, West Indies
16.72 N, 62.18 W; summit elev. 915 m
Dome growth continued from 7 October 2000 through 9 March 2001. Until the
end of February 2001, the growth occurred predominantly on the E side of
the volcano. However, on 25 February, the direction of the growth and the
character of the seismicity changed markedly; the dome growth shifted
towards the S, and the weekly number of hybrid earthquakes increased by
more than an order of magnitude. During this entire period, residents were
advised of the potential dangers associated with pyroclastic flows and
advised to avoid the Belham valley during periods of heavy rain. Access to
Plymouth, Bramble airport, and beyond was prohibited, and a maritime
exclusion zone was declared around the S part of the island extending 3.3
km beyond the coastline. Since November 1999, the dome has grown at an
average rate of nearly 3 m^3/sec and is now at its largest size since the
eruption began in 1995, with a total volume of over 120 x 10^6 m^3 and an
elevation greater than 1,000 m.
Recent MVO assessment. A summary assessment of the volcano's activity,
status, and related risks covering the period from April 2000 through
January 2001 was published recently by MVO. A significant finding from this
assessment was: "While one prognosis is for at least a few more years of
such eruptive activity, an eruption duration measured in decades has to be
contemplated." Other extracts from the report are presented below:
"The period July 1995 to March 1998 was the first phase of the present
eruption. A lava dome grew . . . accompanied by several hazardous phenomena
. . . . There was then a second phase . . . from March 1998 to November
1999. In this phase, no significant dome growth was detected, but hazardous
activity continued . . . . Dome growth resumed in November 1999 . . . [and]
represents a third phase of the eruption."
"The seismic monitoring detected relatively intense periods of rockfall and
long-period (LP) activity . . . from August to October [2000] . . . and
from mid-November 2000 [to January 2001] . . .. There appears to be an
underlying 14-week cycle to this type of seismic activity . . .. However,
hybrid swarms have been rare and weak by comparison with 1997 activity.
Although their generation mechanisms are still poorly understood, hybrid
earthquakes may be related to fracturing of plugs that form in the conduit,
and their absence suggests that conduit conditions may now be subtly
different from previous stages . . .."
"Based on the seismic evidence, the growth of the latest . . . dome seems
to have been different in some respects . . .. The only current prognostic
feature in the observable seismicity is the weak 14-week cycle."
"Volcanic gases continue to be routinely monitored. The flux of sulphur
dioxide over the last ten months has maintained quite high levels . . . .
Occasional measurements of chlorine flux indicate that the flux of chlorine
relative to sulphur dioxide increases . . . when the dome is growing."
"Two key changes have affected the morphology of the volcano since 1998 . .
. which have important implications for hazards. . . . Two remnants of the
1995-1998 dome remain adjacent to the northern wall of English’s Crater.
Over the last year, a narrow gap between the two remnants has gradually
widened and deepened . . .. This deep gully is expected to provide a path
for potential collapses on that side of the dome. Since 1997, Mosquito
Ghaut has been in-filled by pyroclastic-flow and rockfall deposits and no
longer exists as a pathway to channel future pyroclastic flows away to the
[NE]. Thus, collapses moving down the outlet gully will run in a generally
northerly direction, and these topographic changes mean that pyroclastic
flows towards the north are now much more likely to be channeled into the
Belham Valley . . . ."
"The group considered the possibility of tsunami hazards that might affect
other Caribbean islands. Based on modeling studies carried out by French
colleagues a collapse of the current dome . . . into the sea is not
expected to generate a tsunami sufficiently large to affect other islands.
However, new data . . . show that there have been several very large
edifice failures of the Soufriere Hills Volcano in its geological past.
Another collapse of such size would cause a significant regional tsunami
hazard. Thus, any precursory signs of a major edifice failure should
continue to be watched for in the monitoring [program]."
"The duration of the eruption of the Soufriere Hills Volcano now exceeds
about 85% of all documented dome eruptions worldwide. Most dome eruptions
last only a few years, but some have durations measured in decades.
Examples of the latter kind of dome eruption include the Bezymianny volcano
in Kamchatka, Russia, which started to erupt in 1956 and is still active,
and the Santiaguito dome in Guatemala, which started to erupt in 1923 and
is also still active."
"There is currently a lack of clarity about the legal responsibilities and
obligations of the MVO . . . [and other official organizations] in relation
to providing warnings of detected ash injections to civil aviation
authorities. The group recommends that HMG [Her Majesty's Government]
investigate as a matter of urgency where responsibility lies and what
[organization] should issue such warnings."
Activity since 6 October 2000. Until the end of 2000 the summit was
dominated by a broad lava spine inclined at a steep angle towards the E. On
25 October the spine had a peak elevation of 1,030 m and by 13 November had
grown to 1,077 m, the greatest height measured throughout the eruption. On
5 December the top of the spine was at 1,060 m, while the flat top of the
main dome was between 1,020 and 1,030 m. By the end of December the spine
had grown back to 1,071 m. Two large near-vertical spines were observed on
4 February 2001, but both had collapsed by the following week. A large
stubby spine visible in the S part of the summit area on 22 February rose
to 1,068 m.
Rockfalls took place throughout the period. Until 25 February 2001, these
traveled predominantly down the E or NE side of the dome, and occurred
typically in numbers of hundreds per week (table 3). Some of these glowed
and occasionally produced small ash clouds, but none reached altitudes
greater than 3,000 m. These rockfalls contributed to an accumulating talus
fan in the upper reaches of the Tar River valley. The talus began to bury
the remnant buttress of older dome material on the NE flank that formed
during the 1995-98 growth phase. Rockfalls that occurred after 25 February
traveled predominantly S of the dome, mainly in the upper reaches of the
White River valley. (N.B. The White River is sometimes confused with
White’s Ghaut, which lies to the N of the dome.)
Table 3. Seismic and gas data from the Soufriere Hills during 20 October
2000 to 9 March 2001. Courtesy of MVO.
Time Period Rockfall Hybrid Volcano Long Range of Average
Tectonic Period Daily SO2 (t/d)
20 Oct27 Oct 2000 214 9 4 35 2352252
27 Oct03 Nov 2000 146 20 3 19
10 Nov17 Nov 2000 207 33 7 144 no data
24 Nov01 Dec 2000 491 13 69 1020 (28 Nov)
01 Dec08 Dec 2000 547 15 1 72 no data
15 Dec22 Dec 2000 423 12 1 74 400 (20 Dec)
22 Dec29 Dec 2000 708 10 2 53 7451100
12 Jan19 Jan 2001 943 54 345 (18 Jan)
19 Jan26 Jan 2001 417 1 55 330350
26 Jan02 Feb 2001 313 8 21 45 105360
02 Feb09 Feb 2001 409 5 1 40 180500
09 Feb16 Feb 2001 500 2 1 15 80670
16 Feb23 Feb 2001 486 18 6 53 210720
23 Feb02 Mar 2001 729 388 3 58 1801400
02 Mar09 Mar 2001 629 280 4 45 1001230
Pyroclastic flows were also produced throughout the period. A small one on
15 November 2000 traveled N from the summit, entered the upper reaches of
Tyre's Ghaut, and reached ~1 km away from the dome. On 17 November
pyroclastic-flow deposits were noted in the upper reaches of Tuitt's Ghaut
and White's Ghaut on the volcano's NE side; this was the first new dome
material to have traveled down the notch between the N and NE lobes from
the 1995-98 dome. By 8 December 2000 the notch between the central and NE
buttresses of the 1995-98 dome was 60 m wide. Another small flow occurred
down the White River valley on 1 February 2001 and traveled about 1 km from
the dome. On 8 February 2001 new pyroclastic-flow deposits had formed in
the upper portion of Tuitt's Ghaut up to ~300 m from the dome. By
mid-February new pyroclastic-flow deposits had also formed down the Tar
River on the E flank, and, by 23 February, had reached as far as the old
coastline. New deposits were also seen by 23 February in the S White River
valley just 50 m short of the coastline.
On 25 February 2001 a pyroclastic flow spread over the N and central parts
of the White River fan. A hybrid earthquake swarm occurred after this
collapse (table 3). Subsequently, small pyroclastic flows traveled into the
upper portion of the White River valley and were accompanied by banded
tremor and weak hybrid earthquakes. By 9 March steady dome growth appeared
to have resumed.
Seismicity and COSPEC measurements of SO2 are presented in table 3. The SO2
data are in the range of average daily values (in metric tons/day) measured
during the report week and include the range of data obtained from both
helicopter and static mounted sensors.
Background. The complex andesitic Soufriere Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along a ESE-trending zone.
Prior to 1995, the youngest dome was Castle Peak, which was located in
English's Crater, a 1-km-wide crater breached widely to the east.
Block-and-ash flow and surge deposits associated with dome growth
predominate in flank deposits. Non-eruptive seismic swarms occurred at
30-year intervals in the 20th century, but the first well-documented
historical eruption on Montserrat did not take place until 1995. Long-term
small-to-moderate ash eruptions were accompanied by lava dome growth and
pyroclastic flows that initially forced evacuation of the southern half of
the island and then destroyed the capital city of Plymouth.
Information Contact: Montserrat Volcano Observatory (MVO), Mongo Hill,
Montserrat, West Indies (URL: http://www.mvomrat.com/).
#####
This information is from a worldwide network of correspondents, who receive
a Bulletin that includes illustrations not available in this electronic
version of the text. Text, figures, and photographs can also be accessed
the Internet World Wide Web (URL: http://www.volcano.si.edu/gvp/). The
issue date is the closing date for regular monthly reports, not the
publication date; more recent information about ongoing activity is often
included.
* The Bulletin is available by subscription from the American Geophysical
Union, 2000 Florida Ave. NW, Washington, DC 20009 USA, at $22/year for US
addresses, $39/year outside the US.
* The information in our reports is necessarily preliminary, and subject to
change as the reported events are studied in more detail. Please contact
the original sources for updates and corrections before using Bulletin
information.
* The network depends on prompt communication from observers around the
world. Please help by sending news of current activity via Internet
electronic mail (gvn@volcano.si.edu), telephone (202:3571511), fax
(202:3572476), or airletter (Global Volcanism Program, National Museum of
Natural History - Room E-421, Smithsonian Institution, Washington, DC
20560-0129 USA).
#####
_____________________________________________________________________
Ed Venzke
Global Volcanism Program, NMNH E-421 Tel: (202) 357-2822
Smithsonian Institution Fax: (202) 357-2476
Washington, DC 20560-0119 Email: venzke@volcano.si.edu
GVP Webmaster
______________________________________________________________________
Topic 2 of 99 [Geo]: Vulcanism
Response 382 of 997: Marcia (MarciaH) * Tue, Apr 10, 2001 (19:09) * 72 lines
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, April 6, 2001 11:00 AM ADT (1900 UTC)
CLEVELAND VOLCANO (CAVW #1101-24)
52049'N 169057'W
Summit Elevation 5,674 ft (1,730 m)
Unrest at Cleveland Volcano in the east-central Aleutians continues.
Although Cleveland is not monitored directly by seismic instrumentation, an
AVO seismic network 230 km to the east of the volcano has intermittently
recorded low-level volcanic tremor over the last several weeks that is
likely related to activity at Cleveland. Since the eruption of 19 March,
AVO has received no further reports of significant activity from pilots or
residents of Nikolski, and no further explosive activity has been observed
in satellite images. Satellite analysis last confidently detected a thermal
anomaly in the vicinity of the volcano on March 23.
Based on these data and the historical pattern of repeated, sudden
explosions at Cleveland extending over a period of months, AVO reminds
readers that additional ash-producing eruptions are possible at any time.
In addition, movement of recently erupted material from the steep flanks of
Cleveland may produce small, localized ash plumes and avalanches into the
sea.
AVO does not assign a color code to Cleveland because of the lack of a
seismic network immediately around the volcano. We continue to monitor the
situation closely by satellite, through careful analysis of more distant
seismic station data, and by phone contact with air and ground observers in
the region.
OTHER ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
all at or near normal levels of background seismicity. AVO did not detect
ash plumes or significant elevated surface temperatures in the vicinity of
any volcano.
Abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of alaska's volcanoes (907) 786-7478
CONTACT INFORMATION:
Tom Murray, Scientist-in-Charge, USGS
tlmurray@usgs.gov
(907) 786-7497
John Eichelberger, Coordinating Scientist, UAF-GI
eich@gi.alaska.edu(907) 474-5530
The Alaska Volcano Observatory is a cooperative program of the U.S.
Geological Survey, the University of Alaska Fairbanks Geophysical
Institute, and the Alaska Division of Geological and Geophysical Surveys.
Topic 2 of 99 [Geo]: Vulcanism
Response 383 of 997: Marcia (MarciaH) * Tue, Apr 10, 2001 (19:10) * 54 lines
***********************************
Gorda Ridge eruption, Oregon coast
***********************************
From: Dan Shackelford
Submarine eruption off the Oregon coast on the Gorda Ridge
It would appear that a submarine volcanic eruption is taking place off the
Oregon coast, marked by T-Phase seismicity, continuous tremor and near the
February 1996 eruption site on the Gorda Ridge. T-Phase events began about
1800 PST on 3 April and still continued as of 5 April. Seismicity indicates
the reputed eruption began near the summit "narrowgate", with dike
propagation to the S.
Following from:
http://www.pmel.noaa.gov/vents/acoustics/seismicity/nepac/gordaridge01.html
At about 0050Z on JD 094 (Tuesday April 3, 1800 PST), volcanic seismicity
was detected by the PMEL T-phase Monitoring System. The activity is located
on Gorda Ridge. The seismic activity is very similar to earlier JdF events:
no large main shock, rapidly repeating earthquakes, and the presence of a band
of continuous tremor. The event is relatively loud, being heard on
multiple SOSUS arrays and the Pacific Northwest Seismic Network.
The general location (42.15 N, 127.05W (or 42 9'N; 127 3'W) is on the
Jackson segment, just below the North Gorda segment which was the site of a
February 1996 eruption. The activity is analogous to that event, being
located near the summit of the "narrowgate" on the south side and showing
indications of dike propagation.
A response effort is currently planned by the combined event response team
funded by NSF and NOAA using RV New Horizon. New developments will be
broadcast at this site.
UPDATE (4/5 1700PDT): Activity continues at a reduced level; description
information has been updated. A response cruise is planned from Eureka,
California on Monday, April 9th.
UPDATE (4/5 1030PDT): Response planning continues. The Scripps RV New
Horizon may be available in San Diego.
UPDATE (4/5 0830PDT): Activity continued overnight. Several of the larger
earthquakes have been picked up by the Pacific Northwest seismic networks.
A detailed look at the event is under construction and will be posted by
late today. Response planning continues.
UPDATE (4/4-1430PDT): Seismic activity has slowed in the last few hours.
SOSUS-derived earthquake source locations show indications of lateral
migration to the south, typical of dike injections. A current earthquake
location file is provided.
Northwest land seismic arrays have successfully detected at least ten of
the events from this sequence. More information to follow.
Topic 2 of 99 [Geo]: Vulcanism
Response 384 of 997: Marcia (MarciaH) * Fri, Apr 13, 2001 (14:49) * 165 lines
Volcano Watch - April 12, 2001
Volcanoes exempt from capital gains
Here's a riddle for you-which large land holder on the Big Island
condemns property at will, holds liens on large parts of the island, and
doesn't pay a cent of taxes? Kilauea Volcano has seized a lot of real
estate in the last 18 years, but, unlike the rest of us, won't be
struggling with tax forms this weekend.
To date, the eruption that began in 1983 has covered about 102 sq km
(40 sq miles) of preexisting land. Forty percent of that land is inside
Hawai`i Volcanoes National Park. Another 35 percent belongs to the State,
including large parcels of forest reserve and natural area reserve. Only
25 percent of the property covered by this eruption is privately held,
though it included hundreds of house lots.
Most of the private property is near Kilauea's southern coastline,
where the eruption has added about 206 hectares (510 acres) of new land to
the island. The biggest chunk of this lies outboard of the sites of Harry
K. Brown Park and Kaimu black sand beach, where a plain of pahoehoe
extended the coastline seaward by as much as 0.6 km (0.4 mi). The new land
belongs to the State, under the terms of a 1977 Hawaii Supreme Court
decision in the case of the State of Hawaii vs. Zimring. The disputed land
in this case was 7.9 acres formed by the 1955 eruption of Kilauea, which
sent a lava flow into the ocean at Kehena.
The largest remaining kipuka within the flow field contains the
remains of Royal Gardens subdivision, which is located on the steep slope
of Pulama pali. Royal Gardens was the scene of the first house to be
claimed by lava during this eruption, back in early 1983. It is also the
scene of the latest destruction--four long-abandoned houses were overrun in
the last year.
If ever property were subject to a lien by the volcano, it's Royal
Gardens. The subdivision has the dubious distinction of being the only
inhabited area to be impacted by all three of the main epochs of this
eruption. From 1983 through 1985, lava flows from the central vent at Pu`u
`O`o overran the upper slopes of the subdivision. The eruption shifted 3
km (1.9 mi) northeast to the Kupaianaha vent in 1986, and for the next five
years, flows whittled away at the eastern side of the subdivision and
wrapped around its lower end. In early 1992, Kupaianaha died, and the
eruption returned to flank vents on the southwest slope of the Pu`u `O`o
cone. Since then, flows approaching from the west have encroached on the
lower end of the subdivision, merging with the Kupaianaha flows on the
coastal plain. This activity is continuing today.
Most of the land claimed by the volcano during this eruption has been
buried and reburied many times over in the last 18 years, some of it to a
depth of 25 m (80 ft) or more. Currently, surface flows are pushing
eastward on the coastal plain, repaving ground that was first buried in
1989-91 by pahoehoe from Kupaianaha.
Lava hasn't entered the ocean since January of this year, but the
broad surface flows are gradually making their way toward the ocean near
the eastern boundary of the National Park. As of April 12, active lava was
within 400 m (1300 ft) of the shoreline, but judging from its behavior in
the last two months, it's in no hurry to get there.
No earthquakes were reported felt during the week ending on April 12,
2001.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, April 13, 2001 10:00 AM ADT (1800 UTC)
CLEVELAND VOLCANO (CAVW #1101-24)
52°49'N 169°57'W Summit Elevation 5,674 ft (1,730 m)
Unrest at Cleveland Volcano in the east-central Aleutians continues.
Satellite analysis last confidently detected a thermal anomaly in the
vicinity of the volcano on April 8th; the volcano was largely obscured by
clouds during the rest of the week. Low-level pulses of volcanic tremor,
likely related to activity at Cleveland, were detected on several occasions
during the last week by an AVO seismic network 230 km to the east of the
volcano. AVO has received no reports of significant activity from pilots or
residents of Nikolski and no further explosive activity has been observed
in satellite images since the last eruption on March 19.
Based on these data and the historical pattern of repeated, sudden
explosions at Cleveland extending over a period of months, additional
ash-producing eruptions could occur at any time. In addition, movement of
recently erupted material from the steep flanks of Cleveland may produce
small, localized ash plumes and avalanches into the sea.
AVO does not assign a color code to Cleveland because of the lack of a
seismic network immediately around the volcano. We continue to monitor the
situation closely by satellite, through careful analysis of more distant
seismic station data, and by phone contact with air and ground observers in
the region.
OTHER ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
all at or near normal levels of background seismicity. AVO did not detect
ash plumes or significant elevated surface temperatures in the vicinity of
any volcano.
Abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Kamchatkan Volcanic Activity
INFORMATION RELEASE 16-01
Friday, April 13, 2001, 12:30 KDT (2350 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Daylight Time, 21 hours ahead of ADT.
KLYUCHEVSKAYA GROUP OF VOLCANOES
KLYUCHEVSKOY VOLCANO; 56o03'N, 160o39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS YELLOW.
At the beginning of the past week (April 6-12), seismic activity was at
background levels. On April 6-7, a gas and steam plume rose 700-1000 m
above the volcano and extended 5-10 km to the southeast. The level of
volcanic tremor began to increase at 10:00 KDT on April 7, noticeable
increasing in the level of tremor occurred at 13:00 KDT on April 7. Seismic
activity under the volcano increased sharply at 07:17 KDT on April 8 (18:17
UTC on April 7). The swarm of shallow earthquakes (Ml ~ 2) and volcanic
tremor were registered. No volcanic activity was observed. At 8:30 KDT on
April 8, a gas and steam plume rose 400 m above the volcano and extended 5
km to the east. Since 09:00 KDT seismic activity has decreased. In the
evening on April 8, a gas and steam plume rose 100 m above the volcano and
extended 3 km to the southwest. Shallow earthquakes (Ml Less than 2) and weak
volcanic tremor continued to occur during the rest of the week. On April
9-10, the volcano was quiet; on April 11, the volcano was obscured by
clouds. On April 12, a gas and steam plume rose 100 m above the volcano.
BEZYMIANNY VOLCANO; 55o58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity was registered under the volcano. On April 6-8, a gas and
steam plume rose 400-700 m above the volcano and extended to the southeast
on April 6, and 10-20 km to the south on April 7-8. On April 10, weak
fumarolic activity was observed. On April 11-12, the volcano was obscured
by clouds.
SHEVELUCH VOLCANO; 56o38'N, 161o19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
Seismicity was above the background levels. Separate shallow earthquakes,
short series of them, and episodes of volcanic tremor were registered
during the week. Possibly some of these seismic events corresponded to weak
ash-gas and steam-gas explosions. On April 6-8, a gas and steam plume rose
500-800 m above the volcano and extended 5-10 km to the east. At 15:00 KDT
on April 7, a gas and steam explosions to a height of 1500 above the
volcano were observed. On April 10, a gas and steam plume rose 50 m above
the volcano. On other days, the volcano was obscured by clouds.
KARYMSKY VOLCANO; 54o03'N, 159o27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKAYA GROUP OF VOLCANOES; 53o15'N, 158o51'E;
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
MUTNOVSKAYA GROUP OF VOLCANOES:
GORELY VOLCANO; 52o33'N, 158o02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o27'N, 158o12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
Both volcanoes were obscured by clouds the entire week. No seismicity was
registered under the volcanoes.
Topic 2 of 99 [Geo]: Vulcanism
Response 385 of 997: Marcia (MarciaH) * Mon, Apr 16, 2001 (19:47) * 66 lines
**********************************
AVO Weekly Update for 04/13/2001
**********************************
From: avo-sci@usgs.gov
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, April 13, 2001 10:00 AM ADT (1800 UTC)
CLEVELAND VOLCANO (CAVW #1101-24)
52°49'N 169°57'W
Summit Elevation 5,674 ft (1,730 m)
Unrest at Cleveland Volcano in the east-central Aleutians continues.
Satellite analysis last confidently detected a thermal anomaly in the
vicinity of the volcano on April 8th; the volcano was largely obscured by
clouds during the rest of the week. Low-level pulses of volcanic tremor,
likely related to activity at Cleveland, were detected on several occasions
during the last week by an AVO seismic network 230 km to the east of the
volcano. AVO has received no reports of significant activity from pilots or
residents of Nikolski and no further explosive activity has been observed
in satellite images since the last eruption on March 19.
Based on these data and the historical pattern of repeated, sudden
explosions at Cleveland extending over a period of months, additional
ash-producing eruptions could occur at any time. In addition, movement of
recently erupted material from the steep flanks of Cleveland may produce
small, localized ash plumes and avalanches into the sea.
AVO does not assign a color code to Cleveland because of the lack of a
seismic network immediately around the volcano. We continue to monitor the
situation closely by satellite, through careful analysis of more distant
seismic station data, and by phone contact with air and ground observers in
the region.
OTHER ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
all at or near normal levels of background seismicity. AVO did not detect
ash plumes or significant elevated surface temperatures in the vicinity of
any volcano.
Abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of alaska's volcanoes (907) 786-7478
The Alaska Volcano Observatory is a cooperative program of the U.S.
Geological Survey, the University of Alaska Fairbanks Geophysical
Institute, and the Alaska Division of Geological and Geophysical Surveys.
Topic 2 of 99 [Geo]: Vulcanism
Response 386 of 997: Marcia (MarciaH) * Mon, Apr 23, 2001 (05:18) * 132 lines
Volcano Watch - April 19, 2001
April is Earthquake and Tsunami Awareness Month
Early Monday morning, residents of the northern half of the island
were awakened by a magnitude-3.9 earthquake. This was a gentle reminder
that we live in one of most seismically active areas in the United States.
The month of April is observed as earthquake awareness month in the State
of California and as tsunami awareness month in the State of Hawaii. Both
natural hazards have struck this island with disastrous results, so it is
especially important that kama`ainas are reminded, and malihinis are made
aware, of these hazards.
April could also be considered earthquake awareness month here in
Hawai`i because the largest historical earthquake occurred on April 3,
1868, in the Ka`u district. The estimated magnitude of this event was 7.9,
larger than the magnitude-7.8 San Francisco earthquake of April 18, 1906.
The Ka`u earthquake killed a number of people, mainly by a huge landslide
near Kapapala and by a tsunami that swept the coastline.
We observe tsunami awareness month during April because of the
destructive waves that killed 159 people in Hawai`i on April 1, 1946. The
tsunami was generated by a magnitude-7.8 earthquake in the Aleutian trench
south of Unimak Island. The first wave took 4.9 hours to reach Hilo and
caught many residents by surprise. Thereafter, the Seismic Sea Wave
Warning System, later called the Pacific Tsunami Warning System, was
established to provide residents with an early notification if a tsunami is
triggered by a distant Pacific basin earthquake.
The warning system is fine for tsunamis generated by distant
earthquakes, because it takes several hours for the waves to reach Hawai`i.
Large local earthquakes can also cause a tsunami, and the warning system
may not be activated in time for some people to evacuate. The great Ka`u
earthquake and the 1975 Kalapana earthquake (magnitude 7.2) both produced
waves that killed people.
The greatest danger from a locally generated tsunami is the
suddenness with which the waves can materialize. The only warning for such
an event is the strong ground shaking. If you are near the ocean when a
large earthquake occurs, head for high ground immediately; this reaction
may save your life. Campers at Halape, near the epicenter of the 1975
earthquake, had only seconds after the shaking stopped before they were
engulfed and swept away by a series of waves. The tsunami reached Hilo in
20 minutes and Kailua-Kona in 27 minutes. Many fishing boats at both
locations were severely damaged or destroyed.
Hawai`i is a geologically dynamic island with two of the most active
volcanoes in the world. Directly or indirectly, the volcanoes are the
cause of the high seismicity of the island. Monday morning's earthquake
belongs to a family of earthquakes generated by the slow crustal adjustment
to the load or weight of the volcanoes. The most recent large earthquake
from this family was the magnitude-6.2 Honomu earthquake in 1973.
When magma enters a volcano, the edifice has to make room for it, so
the flanks move outward to accommodate the new magma. This flank movement
has caused a number of large earthquakes. Recent earthquakes of this
mechanism include the magnitude-6.7 Ka`oiki fault earthquake in 1983, the
1975 Kalapana earthquake, and the magnitude-6.9 Kealakekua fault earthquake
in 1951.
Awareness of the earthquake hazard in Hawai`i is necessary for
everyone because of such a high frequency of large, destructive local
earthquakes. The hazard will not disappear or diminish, but residents can
reduce the effects of the shaking and also be prepared for the event.
Information on ways to mitigate the earthquake hazard can be obtained from
the Hawai`i County Civil Defense office (935-0031) or from the Center for
the Study of Active Volcanoes (CSAV) at the University of Hawai`i at Hilo
(974-7631). CSAV also has a web site with the necessary information (
http://www.uhh.hawaii.edu/%7Enat_haz/earthmit/eq.html).
Just as the rain in Hilo doesn't fall only in April, awareness of
natural hazards should be a year-round practice.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week and provided visitors with an occasional
glimpse of surface flow activity. Breakouts occur above and on Pulama
pali, in addition to the coastal flats. Lobes of two flows are slowly
advancing to the seacoast at Kamokuna and at Kupapa`u. The flow front
closest to the ocean is within 130 m (425 ft) of the shoreline in the old
Kupapa`u area near the eastern boundary of Hawai`i Volcanoes National Park.
The Monday morning earthquake was reported felt by residents of Hilo,
Papa`ikou, Pa`auilo, Kapulena, Kalopa, Waimea, Hawi, Kawaihae, Waikoloa,
Kailua-Kona, and Keauhou. The 4:18 a.m. earthquake was located near the
Pohakuloa Training Area at a depth of 31.2 km (18.7 mi) and had a magnitude
of 3.9. This was the only event reported felt during the week ending on
April 19.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
Kamchatkan Volcanic Activity
INFORMATION RELEASE 17-01
Friday, April 20, 2001, 11:30 KDT (2230 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Daylight Time, 21 hours ahead of ADT.
KLYUCHEVSKAYA GROUP OF VOLCANOES
KLYUCHEVSKOY VOLCANO; 56o03'N, 160o39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
During the past week (April 13-19), seismic activity was above background
levels. A strong earthquake (Ml~5) occurred between Klyuchvskoy and
Krestovsky volcanoes at 12:59 KDT on April 13, at a depth of ~12 km.
Aftershocks of this event (Ml greater than 4.2) continued to occur during the entire
week. Small shallow earthquakes under Klyuchvskoy volcano were registered
too. On April 16, a gas and steam plume rose 150 m above the volcano and
extended more than 3 km to the southeast. On other days the volcano was obscured
by clouds.
BEZYMIANNY VOLCANO; 55o58'N, 160o36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
On April 19, one small earthquake was registered under the volcano. On
April 16, the volcano was quiet. On other days, the volcano was obscured
by clouds.
SHEVELUCH VOLCANO; 56o38'N, 161o19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
Seismicity was above the background levels. Shallow earthquakes (Ml greater than 2)
continued to occur. On April 13 and 16, a gas and steam plume rose 100-200
m above the volcano. On other days, the volcano was obscured by clouds.
KARYMSKY VOLCANO; 54o03'N, 159o27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKAYA GROUP OF VOLCANOES; 53o15'N, 158o51'E;
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
MUTNOVSKAYA GROUP OF VOLCANOES:
GORELY VOLCANO; 52o33'N, 158o02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o27'N, 158o12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On April 19, both volcanoes were quiet. On other days, both volcanoes were
obscured by clouds. Seismicity was near background levels.
Topic 2 of 99 [Geo]: Vulcanism
Response 387 of 997: Marcia (MarciaH) * Mon, Apr 23, 2001 (15:25) * 12 lines
Nicaragua Volcano Erupts, Hurts 2
The Associated Press
Apr 23 2001 11:03PM
MANAGUA, Nicaragua (AP) - A volcano erupted near the capital Monday
and rained red-hot rock over vehicles on a road below, slightly injuring
two people and shattering windows on a bus carrying American tourists.
The eruption of the 2,086-foot Santiago volcano also spewed volcanic
ash over several nearby hamlets, but there were no reports of any injury
or damage, officials said.
More... http://my.aol.com/news/news_story.psp?type=1&cat=0600&id=0104232309090612
Topic 2 of 99 [Geo]: Vulcanism
Response 388 of 997: Marcia (MarciaH) * Wed, Apr 25, 2001 (05:51) * 55 lines
***************************
Masaya Volcano, Nicaragua
***************************
From: Wilfried Strauch
Report to Volcano Network
Explosion at Masaya volcano, Nicaragua
New vent in Santiago crater
Yesterday, April 23, 2001, at 02:26 PM local
time (8:26 UT), an explosion occurred in
the crater Santiago of Masaya volcano.
This explosion formed a new vent in the bottom
of Santiago. The explosion first launched
rocks with diameters up to 60 cm which impacted
at distances up to 500 m from the crater.
Vehicles parked at the visitors platform
were damaged and one person was injured. In
the moment of the explosion about 200 persons
were present at or near the visitors platform.
In a second and third phase of the explosion
small quantities of lava and volcanic ash
were expulsed which caused bush fires near
the crater rim. The seismic recording at
the seismic station installed near the
crater shows that the explosion lasted about
2 minutes. Degassing continued stronger than
in the last weeks and months.
Episodic ash fall was reported near
Ticuantepe, Northwest of Masaya volcano and
people were affected by high concentrations
of volcanic gases. INETER volcanologists
who continuously monitored Santiago in
the afternoon and during the night
reported several smaller explosions, gas
outbreaks and minor collapses of the crater wall.
Scientists from Cambridge University/UK
who carried out gas measurements at
Santiago crater and left just one hour before
the explosion had not noticed any unusual
behavior of the volcano before the event.
Also, the seismic recordings, according
to preliminary inspection, does not
indicate unusual activity.
The authorities of the National Park of
Masaya Volcan closed public access to the
visitors platform for the next days.
The official report of INETER,
additional information and photos can be
found in our Web page
http://www.ineter.gob.ni/geofisica/vol/masaya/masaya.html
Topic 2 of 99 [Geo]: Vulcanism
Response 389 of 997: Marcia Hemming (marci) * Fri, Apr 27, 2001 (00:59) * 1 lines
test 2
Topic 2 of 99 [Geo]: Vulcanism
Response 390 of 997: Marcia (MarciaH) * Fri, Apr 27, 2001 (12:01) * 1 lines
Ooh! telnet works!!!
Topic 2 of 99 [Geo]: Vulcanism
Response 391 of 997: Marcia Hemming (marci) * Sun, Apr 29, 2001 (10:03) * 1 lines
Yes, but I am talking to myself in Telnet *sigh*
Topic 2 of 99 [Geo]: Vulcanism
Response 392 of 997: Marcia (MarciaH) * Mon, Apr 30, 2001 (08:31) * 372 lines
GVP/USGS Weekly Volcanic Activity Report 18-24 April 2001
http//www.volcano.si.edu/gvp/usgs/
New Activity/Unrest | Marapi, Indonesia | Masaya, Nicaragua |
Ongoing Activity | Batur, Indonesia | Cleveland, USA | Etna, Italy | Ijen,
Indonesia | Kilauea, USA | Mayon, Philippines | Merapi, Indonesia |
Popocatépetl, México | Semeru, Indonesia | Shiveluch, Kamchatka | Soufrière
Hills, Montserrat | Tungurahua, Ecuador |
New Activity
MARAPI Sumatra, Indonesia 0.38°S, 100.47°E; summit elev. 2,891 m
Based on information from VSI, the Darwin VAAC reported that after
increased volcanic activity occurred over the preceding two weeks VSI
raised the Alert Level at Marapi from 1 to 2. The increased activity
included an eruption on 16 April that sent an ash cloud up to 2 km above
the summit. In addition, an eruption on about 23 April produced an ash
cloud that rose up to ~6 km a.s.l. and drifted to the E.
Background. Gunung Marapi, not to be confused with the better known Merapi
volcano on Java, is Sumatra's most active volcano. Marapi is a massive
complex stratovolcano that rises 2,000 m above the Bukittinggi plain in
Sumatra's Padang Highlands. A broad summit contains multiple partially
overlapping summit craters constructed within the small 1.4-km-wide Bancah
caldera. The summit craters are located along an ENE-WSW line, along which
volcanism has migrated to the W. More than 50 eruptions, typically
consisting of small-to-moderate explosive activity, have been recorded
since the end of the 18th century; no historical lava flows outside the
summit craters have been reported.
Sources Volcanological Survey of Indonesia,
http//www.vsi.dpe.go.id/news/index.html Darwin, VAAC
http//www.bom.gov.au/info/vaac/
Marapi Reports
http//www.volcano.si.edu/gvp/volcano/region06/sumatra/marapi/var.htm
from the monthly Bulletin of the Global Volcanism Network
MASAYA Nicaragua 11.984°N, 86.161°W; summit elev. 635 m; All times are
local (= UTC - 6 hours)
At 1426 on 23 April a small explosion at Masaya’s Santiago crater lasted
for ~2 minutes and occurred in three phases. During the first phase
volcanic gas under high pressure was explosively released and created a new
vent in the bottom of Santiago crater. The eruption sent rock fragments up
to 60 cm in diameter as far as 500 m from the crater. Several vehicles
parked at a visitors platform near the crater were damaged by the ejecta
and one person suffered minor injuries. During the second and third phases
a mixture of hot volcanic gas, pieces of lava, and ash ignited dry
vegetation near the crater. INETER personnel who monitored the seismic
activity before the eruption and scientists from Cambridge University who
were working in the crater one hour before the eruption did not notice any
unusual activity at the volcano. INETER personnel monitored the volcano
after the eruption and found that several small explosions, gas outbreaks,
and minor collapses of the crater wall occurred. They warned that further
explosions may occur that could affect areas near the crater (within ~500 m).
Background. Masaya is one of Nicaragua's most unusual and most active
volcanoes. It is a broad, 6 x 11 km basaltic caldera with steep-sided walls
up to 300 m high that is filled on its NW end by more than a dozen vents
erupted along a circular, 4-km-wide fracture system. The twin volcanoes of
Nindiri and Masaya, the source of historical eruptions, were constructed at
the southern end of the fracture system and contain multiple summit
craters. A major basaltic plinian tephra was erupted from Masaya about
6,500 years ago. Historical lava flows cover much of the caldera floor and
have confined a lake to the far eastern end of the caldera. A lava flow
from the 1670 eruption overtopped the N caldera rim. Masaya has been
frequently active since the time of the Spanish Conquistadors, when an
active lava lake prompted several attempts to extract the volcano's molten
"gold."
Sources Instituto Nicaragüense de Estudios Territoriales
http//www.ineter.gob.ni/geofisica/vol/masaya/masaya.html, Associated Press
http//dailynews.yahoo.com/h/ap/20010423/wl/nicaragua_volcano_1.html
Masaya Reports
http//www.volcano.si.edu/gvp/volcano/region14/nicarag/masaya/var.htm
from the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
BATUR Lesser Sunda Islands, Indonesia 8.24°S, 115.37°E; summit elev. 1,717 m
VSI reported that there were no major changes visible at Batur during 9-15
April. Thin steam plumes continued to rise above the volcano’s crater.
Seismographs recorded no shallow volcanic earthquakes, two deep volcanic
earthquakes, two small explosion earthquakes, and 17 tectonic earthquakes.
The volcano remained at Alert Level 2 (on a scale of 1-4).
Background. The historically active Batur volcano is located at the center
of two concentric calderas NW of Agung volcano in eastern Bali. The SE
side of the larger 10 x 13 km caldera contains a caldera lake. The inner
7.5-km-wide caldera, which was formed during emplacement of the Bali (or
Ubud) ignimbrite, has been dated at 23,670 and 28,500 years ago. The SE
wall of the inner caldera lies beneath Lake Batur; Batur cone has been
constructed within the inner caldera to a height above the outer caldera
rim. The Batur stratovolcano has produced vents over much of the inner
caldera, but a NE-SW fissure system has localized the Batur I, II, and III
craters along the summit ridge. Historical eruptions have been
characterized by mild-to-moderate explosive activity sometimes accompanied
by lava flows from summit and flank vents that have reached the caldera
floor and the shores of Lake Batur.
Source Volcanological Survey of Indonesia
http//www.vsi.dpe.go.id/news/index.html
Batur Reports
http//www.volcano.si.edu/gvp/volcano/region06/sunda/batur/var.htm
from the monthly Bulletin of the Global Volcanism Network
CLEVELAND Aleutian Islands, USA 52.82°N, 169.95°W; summit elev. 1,730
Volcanic unrest continued at Cleveland through 20 April. A thermal anomaly
was persistently detected in satellite imagery on days when the weather was
clear to partly cloudy. Low-level pulses of volcanic tremor were detected
several times during the week by an AVO seismic network 230 km to the E of
the volcano. AVO received no reports of significant volcanic activity from
either pilots, residents, or satellite remote sensors.
Background. The symmetrical Mount Cleveland stratovolcano is situated at
the western end of the uninhabited dumbbell-shaped Chuginadak Island in the
east-central Aleutians. The 1,730-m-high stratovolcano is the highest of
the Islands of Four Mountains group and is one of the most active in the
Aleutians. Numerous large lava flows descend its flanks. It is possible
that some 18th to 19th century eruptions attributed to Carlisle (a volcano
located across the Carlisle Pass Strait to the NW) should be ascribed to
Cleveland. In 1944 Cleveland produced the only known fatality from an
Aleutian eruption. Recent eruptions from Mt. Cleveland have been
characterized by short-lived explosive ash emissions, at times accompanied
by lava fountaining and lava flows down the flanks.
Source Alaska Volcano Observatory
http//www.avo.alaska.edu/avo4/updates/updates.htm
Cleveland Reports
http//www.volcano.si.edu/gvp/volcano/region11/aleutian/cleve/var.htm
from the monthly Bulletin of the Global Volcanism Network
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
Sistema Poseidon reported that during 9-15 April volcanic activity at Etna
was similar to the previous week. Strombolian activity continued at Bocca
Nuova crater, although by the end of the report period activity decreased
in comparison to previous weeks. Lava also continued to flow down the NE
flank of Southeast Crater, and degassing continued at Voragine and
Northeast craters. The Australian Broadcasting Corporation reported that on
about 22 April thirty small earthquakes occurred near Etna, but did not
cause any injuries or property damage.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Source Sistema Poseidon, http//www.poseidon.nti.it/ Australian
Broadcasting Corporation
http//www.abc.net.au/news/newslink/weekly/newsnat-23apr2001-19.htm
Etna Reports
http//www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm
from the monthly Bulletin of the Global Volcanism Network
IJEN eastern Java, Indonesia 8.058°S, 114.242°E; summit elev. 2,386 m
Volcanic activity at Ijen during 9-15 April was higher than normal, with a
relatively large number (nine) of shallow volcanic earthquakes.
Seismographs also recorded ten small explosion events. The volcano remained
at Alert Level 2 (on a scale of 1-4).
Background. The Ijen volcano complex consists of a group of small
stratovolcanoes constructed within the large 20-km-wide Ijen (Kendeng)
caldera. The N caldera wall forms a prominent arcuate ridge, but elsewhere
the caldera rim is buried by post-caldera volcanoes, including Gunung
Merapi stratovolcano, which forms the 2,799 m high point of the Ijen
complex. Immediately W of Gunung Merapi is the renowned historically
active Kawah Ijen volcano, which contains a nearly 1-km-wide,
turquoise-colored, acid crater lake. The picturesque lake is the site of a
labor-intensive sulfur mining operation, in which sulfur-laden baskets are
hand-carried from the crater floor. A half dozen small-to-moderate
phreatic eruptions have taken place from Kawah Ijen during the 20th century.
Source Volcanological Survey of Indonesia
http//www.vsi.dpe.go.id/news/index.html
Ijen Reports
http//www.volcano.si.edu/gvp/volcano/region06/java/ijen/var.htm
from the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Surface lava flows were visible above the Pulama Pali and traveling down it
without reaching the coast. The lava flows were predominately pahoehoe with
minor `a`a. Generally, volcanic tremor near Pu`u `O`o cone and in Kilauea's
caldera was at low levels, although a swarm of long-period earthquakes
occurred beneath the caldera from 18 to at least 24 April. Tiltmeters in
the summit area and along the east rift zone indicated no significant
deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source US Geological Survey Hawaiian Volcano Observatory
http//hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http//www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m; All times are local (= UTC + 8 hours)
PHIVOLCS reported that during the week ending on 15 April there had been a
total of 60 low-frequency earthquakes and 13 high-frequency short-duration
harmonic tremors. The SO2 flux during the same period averaged 3,400 metric
tons/day, which is still significantly above the baseline value of 500
tons/day. Deformation monitoring showed that the volcano was inflated, but
the present trend revealed insignificant change. Moderate steaming was
typical. Faint incandescence was observed at the crater using a telescope
for approximately an hour on both 16 and 17 April; the incandescence was
graded as level 1 intensity. Alert Level 3 remained in effect, prohibiting
entry within the 6-km-radius permanent danger zone.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Source Philippine Institute of Volcanology and Seismology
http//www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
Mayon Reports
http//www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm
from the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
VSI reported that during 9-15 April lava avalanches continued to fill the
upstream areas of the Sat, Senowo, Lamat, and Bebeng rivers, with a maximum
runout distance of 2 km in the Sat River. In addition, eleven pyroclastic
flows entered the Sat and Lamat rivers, reaching as far as 3 km. Avalanche
earthquakes continued to dominate the seismicity, but their amplitude and
frequency decreased in comparison to the previous week. An observer
reported that on 13 April a small amount of ash fell around the Babadan
Post Observatory ~7 km W of the volcano. Merapi remained at Alert Level 2
(on a scale of 1-4).
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Source Volcanological Survey of Indonesia,
http//www.vsi.dpe.go.id/news/index.html
Merapi Reports
http//www.volcano.si.edu/gvp/volcano/region06/java/merapi/var.htm
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m
Small-to-moderate exhalations continued at Popocatépetl. On 17 April a
small lahar traveled down the Achupashal Gorge. The volcano remained at
Alert Level Yellow Phase III, with a restricted 12-km-radius area.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site) http//www.cenapred.unam.mx/boletines.html
Sources Centro Nacionale de Prevencion de Desastres,
http//www.cenapred.unam.mx/boletines.html
Washington VAAC, http//www.ssd.noaa.gov/VAAC/vaac.html, Associated Press
http//dailynews.yahoo.com/h/ap/20010417/wl/mexico_volcano_1.html
Popocatépetl Reports
http//www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html
from the monthly Bulletin of the Global Volcanism Network
SEMERU Java, Indonesia 8.11°N, 112.92°E; summit elev. 3,676 m
VSI reported that during 9-15 April activity at Semeru was higher than
normal. Minor explosions that rose 300 m were observed during clear
weather. Seismographs recorded an increase in seismicity in comparison to
the previous week, with 339 explosion events, 51 avalanche events, and
three tectonic earthquakes. Semeru remained at Alert Level 2 (on a scale of 1-4).
Background. Semeru is the highest volcano on Java and one of its most
active. The symmetical stratovolcano rises abruptly to 3,676 m above
coastal plains to the S and lies at the southern end of a volcanic massif
extending N to the Tengger caldera. Semeru has been in almost continuous
eruption since 1967. Frequent small-to-moderate Vulcanian eruptions have
accompanied intermittent lava dome extrusion, and periodic pyroclastic
flows and lahars have damaged villages below the volcano. A major secondary
lahar on 14 May 1981 caused more than 250 deaths and damaged 16 villages.
Source Volcanological Survey of Indonesia http//www.vsi.dpe.go.id/
Semeru Reports
http//volcano.si.edu/gvp/volcano/region06/java/semeru/var.htm
from the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
During 13-20 April seismic activity was above background levels at
Shiveluch before increasing sharply on 22 April. Heavy clouds prevented
visual observations of the volcano, but seismic data suggested that no ash
explosions occurred. Due to the high seismic activity KVERT raised the
Concern Color Code from Yellow to Orange
http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http//www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev.
1,030 m; All times are local (= UTC - 4 hours)
MVO reported that during 13-20 April volcanic activity at Soufrière Hills
remained low, with few rockfalls and little seismicity. A swarm of hybrid
earthquakes occurred primarily during 0419 to 0741 on 20 April. A very
small amount of growth occurred on the S side of the lava dome, which was
accompanied by occasional ash venting. Sulfur dioxide flux also remained low.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source Montserrat Volcano Observatory http//www.mvomrat.com/
Soufrière Hills Reports
http//www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m
IG stated that during the night of 20 April incandescence was visible in
the interior of the dome and the next day a steam column rose a short
distance above the summit. IG warned that residents near the volcano should
be alert to the possibility of mud flows forming during periods of heavy
rain. Since 5 September 2000, the Alert Level has been at Yellow in the
town of Baños and at Orange for the rest of the population in the high-risk
zone.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted the evacuation of the
town of Baños on the N side of the volcano.
Source Instituto Geofísico, http//www.epn.edu.ec/~igeo/index.html,
Washington VAAC http//www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http//www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 393 of 997: Marcia (MarciaH) * Thu, May 3, 2001 (05:11) * 44 lines
*********************************************
KVERT Information Release 22-01: May 1, 2001
*********************************************
From: avo-sci@usgs.gov
KVERT Information Release 22-01: May 1, 2001
Kamchatkan Volcanic Activity
INFORMATION RELEASE 22-01
Tuesday, May 1, 2001, 16:00 KDT (0300 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity under Sheveluch volcano increased sharply on April 22. At
18:40 KDT on April 21, the volcano was quiet. After that, right up to April
28, clouds obscured the volcano and prevented visual observation. Seismic
activity continued to increase. In the morning on April 27, the largest
earthquake reached Ml=4. Beginning from April 28, the number and the energy
of the events began to decrease slightly. In the morning on April 28, a gas
and steam plume rose 300 m above the volcano and extended 5 km to the west.
On April 29, a gas and steam plume rose 700 m above the volcano and
extended 10 km to the west. The satellite image (AVO) from April 30 at
07:39 KDT (18:39 Z on April 29), showed a 4-pixel thermal anomaly at the
volcano. At 08:30 KDT on April 30, a gas and steam plume rose 50 m above
the volcano and extended 5 km to the east. In the evening on April 30 and
in the morning on May 1, a gas and steam plume rose 100-200 m above the
volcano. Seismic activity continues to be significantly above background
levels. The course of the present seismic activity suggests that if an
eruption occurs, it may be similar to that of April 1993.
The 1993 eruption was preceded by a significant increase in volcanic and
seismic activity. On April 1, 1993, the rate of occurrence of earthquakes
under the volcano began to increase. At 11:40 KDT on April 22, the ash
cloud rose ~ 8 km above the dome. A violent explosion occurred at 13:16
KDT. The height of the eruption column was estimated at ~18 km above the
volcano. At 18:30 KDT ash began to fall in Klyuchi town (~46 km from the
volcano). Mud flows extended from the volcano 15-20 km. During the next
few days, the gas-steam column rose 1.5-4 km above the volcano.
Topic 2 of 99 [Geo]: Vulcanism
Response 394 of 997: Marcia (MarciaH) * Sun, May 6, 2001 (08:03) * 167 lines
*************************
Indonesia Update No. 612
*************************
From: Dan Shackelford
For the week ending 23 April, Indonesia's Marapi volcano (Sumatra), after a
period of decreased activity in Jan - Feb, began showing increased activity
in April. B-type earthquakes began on 7 April, on 9 April continuous tremor
began, and eruptions began at 1238 on 13 April. Thick dark ash columns rose
from the summit through 15 April. Strong explosion at 0814 on 16th, being
"felt" at the Tandikat Volcano Observatory, while a black ash cloud rose 2
km and spread ash over the area. Eruptions still continuing as of 18 April.
Java's Merapi continued to send glowing lava avalanches down its flanks
while a white plume rose 500m above the summit. Api Siau (Karangetang)
showed increased level of activity. Not only did both craters loft fume
with glows at the Main Crater, but lava avalanches and a short lava flow
down the N flank also took place from the Main Crater. Semeru displayed
increased seismic and visible activity as well, continuing its recent trend
for heightened levels of activity. The volcanoes of Lokon-Empung, Inielika,
Kawak Ijen, Anak Krakatau, Soputan, Batur and Kelut, although not erupting,
do remain restless, seismically.
Following from: Suswati (suswati@VSI.dpe.go.id)
http://www.vsi.dpe.go.id/news/
Weekly Report No. 612
16-23 April 2001
MARAPI
Sumatera, Indonesia
0°22'47,72" N, 100°28'16,71"E
summit elevation 2891,3 m
All times are local (=GMT + 7 hours)
Marapi has shown its eruption activity in the year 2001. Reports from
Marapi Volcano Observatory at Bukittinggi to the Geological Hazard
Mitigation and Volcanological Survey of Indonesia described decreasing of
seismicity since January to February 2001. A-type and B-type volcanicquakes
decreased from 15 and 24 times in January to 8 and 14 times in February,
respectively. Meanwhile, gas and steam emissions were increasing from 11 to
41 times from January to February 2001.
Chronology
Marapi activity began on April 7th 2001 with the occurrences of B-type
volcanicquakes. On April 9th continuously volcanic tremor were recorded.
Eruptions started at 12:38 pm until 16:00 pm on April 13th. At 16:00 April
14th a thick dark ash plume seen from Bukittinggi 15 km northwest of Marapi
summit. The eruptions continued to occur at 13:11 pm on April 15th.
On April 16th, at 08:14 am, an explosion was heard very strong to the
radius 8 km from the summit and felt with I = II MMI scale at Tandikat
Volcano Observatory. A black volcanic ash plume rose to a height of 2000 m
above the summit and showed cauliflower shape. Red ejected materials (ash,
sand, lapili and bomb) are seen clearly from Bukittinggi and fall back to
the crater rim. Ash fall spread over villages of Sungai Puah, Air Angeh,
Andala, District X Koto, District Batipuh, District V Koto, Tanah Datar
Regency and Padang Panjang City, respectively, in the southern and
southwestern parts of the volcano. The thickness of the ash deposits is
between 2 and 3 cm, within the radius of 1-4 km from the summit.
Leading to the 16th April's explosion, a smaller scale explosion occurred
at 06:00 am with a thick black ash plume rising to the height of 700 m
above the summit. A series of explosions continuously occurred at 14:15 pm,
19:40 pm and from 21:00 pm to 22:40 pm. Explosive activity was continuing
until the 18th April 2001, and 150 times explosions were counted.
No casualty was reported and the Marapi Volcano Observatory increased
alert level from "NORMAL" (1) to "WASPADA" (2) following minor activity
that began on 13 April 2001. A recommendation has been issued by local
government to prevent the people to reach the summit area.
Background
Marapi volcano has a long history of eruptions, recorded back from 1770,
with a thick black ash plumes showing a cauliflower shape rising to more
than 1000 m above the summit, and many times accompanied by lava flows,
glowing ejected sand, lapili and volcanic bomb.
Marapi 16th April 2001 eruption seems to occurred from Verbeek crater, one
out of many craters at the summit. Historically, Marapi eruptions took
place along ENE-WSW craters aligment, 1600 m long, consisting of Kapundan
Tuo, Kebung Bungo, A-,B-,C- craters, Kapundan Bongsu, and Verbeek crater,
with diameters 175-600 m, at the summit. The event usually has few days,
weeks or months to occur.
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Both of glowing lava avalanche and solfatara activity are ongoing.
Solfatara was in white thick color, low in pressure reached 500 m height
above the summit. Glowing lava avalanches flowed down to Sat, Senowo, Lamat
and Bebeng river, travelled about 2.5 km. Seismicity was still dominated
with avalanche earthquakes.
Merapi volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
Plume activity from Tompaluan crater is continuing hit 50-300 m height.
Seismograph recorded 2 events of deep volcanic (A) earthquake, 31 events of
tectonic and 2 events of tremor earthquake.
Lokon volcano is in level 2.
Inelika
Central Flores; 8°44' S, 120°59' E
Seismograph noted an increasing activity on Inelika volcano. Seismic record
within the week were: 5 events of deep volcanic (A), 10 events of shallow
volcanic (B), and 11 events of tectonic earthquake.
Inelika volcano is in level 2.
Karangetang
Siau island; 2°47' N, 125°29' E
White medium-grey plume from main crater hit 50-300 m height, meanwhile
white-medium plume from crater II rose 200 m above the summit. Red-colored
reflection could be observed at night, reached 25 m height. There was lava
flow activity from northern part of crater I with the distance of 50 m, and
lava avalanche often occurred from the end of lava flow, traveled about 750
m to Nanitu river. Low-medium noising sound often heard from post
observatory.
Karangetang volcano is in level 2.
Ijen
East Java;8°3.5' S, 114°14.5' E
Seismicity data showed an increasing activity which reflected from an
increasing number of shallow volcanic earthquake. Complete seismicity
records listed below: 1 event of deep volcanic (A), 10 events of shallow
volcanic (B), and 2 events of tectonic earthquake.
Ijen volcano is in level 2.
Semeru
East Java; 8°6.50' S, 112°55' E
Within the report Semeru showed an increasing activity compare to the week
before. Seismograph recorded a significant increasing in explosion
earthquake and deep volcanic earthquake. Detail data listed as follow: 8
events of deep volcanic (A) earthquake, 550 events of explosion, 149 events
of avalanche, and 10 events of tectonic earthquake. Gas explosion was in
grey color, rose 300 m above the summit.
Semeru volcano is in level 2.
Anak Krakatau
Sunda Straits, 6°6'5.8" S, 105°25'22.3" E
Number of Krakatau seismicity is still high but less than previously,
mainly in deep volcanic earthquake. During the reporting time seismograph
recorded 1 event of deep volcanic (A), 66 events of shallow volcanic (B),
and 3 events of tectonic earthquake.
Anak Krakatau is stated in level 2.
G. Soputan
North Sulawesi,124º41’12"N, 1º6’20"E
There was no major changes in Soputan activity based on visual and
instrumental monitoring. Visual observation noted 50 m height of plume.
Amplitude of tremor volcanic is about 0.5 - 3 mm. Observer reported an
increasing number of deep volcanic (A) earthquake. Complete data were: 9
events of deep volcanic (A), 30 events of tectonic, 37 events of avalanche
earthquake, and uncontinuous tremor volcanic earthquake.
Soputan is stated in level 2.
G. Batur
Bali Island
115.37° N, 8.24° E, summit elevation 1717 m
Visual observation could not be done well during the week. Data from
seismicity record listed as follow: 1 event of shallow volcanic, 2 events
of small explosion and 10 events of tectonic earthquake.
Batur volcano is in level 2.
Kelut
East Java;7°56' S, 112°18.5' E
There was no major changing showed from the volcano by visual observations.
Water lake temperature decrease than previous data. Measurement on 2 April
2001was 48.5°C and on 9 April 2001 was 48°C.
Kelut volcano is in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 395 of 997: Marcia (MarciaH) * Sun, May 6, 2001 (10:27) * 44 lines
1902 was a bad year for volcanic eruptions around the world but none
more so than in the Caribbean where in the space of 2 days 2 volcanoes
killed 32,000 people.
It all began in April 1902 when Pelee on the French Dependency of
Martinique started letting of steam. Nearby was the picturesque city and
port of Saint Pierre with its 31000 people. Initially no one took any
notice of Pelee as the local government elections were getting close and
the government wanted everyone to vote. That was in early April at a time
when the occasional puff of steam rose out of the crater. Then things
started going wrong.
For the next month the volcano continued to gently steam with small
volumes of ash streaking the white steam clouds. As April drew to a close,
explosions, weak at first but growing in intensity and violence began
bracketing the volcano. A few people left but were lured back when the
government said all would be alright, and that the volcano was harmless.
So they all came back, and got on with their lives.
On nearby St Vincent, another French Dependency, the volcano of Mount
Soufriere (appropriately named in French because of the sulphurous odour
tht accompanied eruptions), was also letting of steam. The volcano had
on its flanks a thriving agricultural industry and several thousand
people lived nearby. In early May, the eruptions took a serious turn for
the worse as steam clouds were replaced by explsions and flying rocks.
Back in Saint Pierre news about worsening activity in the crater caused
the governor to travel to the town to calm the residents, in the first
of three trips in the following week. Two days later on May 2 the first
blood was drawn when two people went into the crater and were surprised
by an explosion of hot water and rocks. A few people left the city for
safer places. Earthquakes were starting to rock the city and light ash
fell occasionally, fraying nerves and prompting a government call for
calm. On May 4, a loud explosion was heard, and ash fell for an hour
with the night sky lit up by lightning and the air punched by thunder.
The following day a mudflow rushed down a river valley and straight
through a flour mill killing 100 people. Panic set in and several families
left, despite the governor making another vist. All was not well.
Meanwhile things had also turned sour on St. Vincent where heavy ash
was falling on the island making agricultural practices impossible
because every rainstorm turned the ash into mud. No one was getting any sleep
and now earthquakes were rocking the island with annoying frequency.
Soufriere would not hang on much longer.
Continued Next Post.........
Topic 2 of 99 [Geo]: Vulcanism
Response 396 of 997: Marcia (MarciaH) * Sun, May 6, 2001 (10:29) * 50 lines
Pelee, in the meantime had started to panic the most settled residents
with frightening explosions of ash and rock, by day, by night and
everytime inbetween. On the morning of May 6 Pelee sent it's final warning:
GET OF MY PATCH NOW OR I WILL BLOW YOU TO KINGDOM COME. That night
explosions rocked the city almost hourly, thunder and lightning
reverberated through the night, ash fell leaving a sulphurous odour behind
children ran screaming from their houses. No one was laughing any
longer, the birds had gone and ships were leaving port just in case the
volcano turned rough. That day an event on St. Vincent set the tone of the
two volcanoes for the next 48 hours.
For two weeks Mount Soufriere had been steaming and snorting ash.
People were leaving but not fast enough for the volcano which now proceded
to up the ante with as we will now see, shocking results. It was a fine
day in the Caribbean and despite the ominous presence of the volcano,
people continued their lives as best as they could. Suddenly there is a
series of powerful explosions and the volcano sends pyroclastic flows
rushing down the flanks of the mountain to the sea. There is nowhere to
run, nowhere to hide. People die in their hundreds as the worst
eruptions for nearly a century shatter the fabric of life on the island. It is
May 7 1902 and the grim reaper is about to reap..............
May 7 should have seemed like any other day on Saint Pierre under
normal circumstances, but it was not. Now under siege from a volcano looming
large on its horizon, the governor decided to make his third visit to
the city that was now resemblimg something out of a horror movie.
Throughout the day explosions bracketed the volcano while earthquakes rocked
the island and frightened the citizens. Most ships had by now left and
although several returned later in the day, many would never see the
Saint Pierre their crews knew again. As night fell, the air was humid and
sticky and thunderstorms driven by both the volcano and the weather
kept most awake the whole night. Several hundred people moved to the
ridges above the city fearing the worst. Ascension Day May 8 1902. A day
that will be forever be written in blood. At 7.52AM that sunny morning,
Montagne Pelee finally lost all control and exploded. A pyroclastic flow
roared down every ravine and gully on the volcano. It filled the sky
and the horizon as people watched an incandescent dragon snuff out in 2
minutes an entire city, boats and eventually them, themselves. There was
nowhere to run and seemingly nowhere to hide as the flow went through,
over and around every building, bar the jail where Pierre Auguste, a
wanted murderer was awaiting execution. By a miracle he survived the flow
and resulting carnage to tell his story to the newspapers and he was
pardoned.
By 7.57AM it was all over. A city on fire, all bar 100 people dead or
dying, and a government trying to explain how it could still think of an
election.
THANKS, ROB... http://clubs.yahoo.com/clubs/worldvolcanism
Topic 2 of 99 [Geo]: Vulcanism
Response 397 of 997: Marcia (MarciaH) * Tue, May 8, 2001 (08:19) * 85 lines
http://www.usgs.gov/public/press/public_affairs/press_releases/index.html
Three Sisters Show Ground Deformation
There has been a slight swelling, or uplift, of the ground surface over a
broad area of central Oregon, centered five kilometers, or three miles,
west of the South Sister volcano in Three Sisters region of the Oregon
Cascade Range, according to scientists at the U.S. Geological Survey. The
Three Sisters region is located 35 kilometers (22 miles) west of Bend,
Ore., and 100 kilometers (60 miles) east of Eugene. The uplift, which
scientists say occurred between 1996 and 2000, covers an area about 15 to
20 kilometers (9 to 12 miles) in diameter. The maximum amount of uplift at
its center is about 10 centimeters (4 inches). It is too broad and low to
be noticed from the ground, and several close aerial inspections of the
area have revealed no unusual surface features.
The USGS scientists discovered the bulge through use of a relatively new
technique called Satellite Radar Interferometry (InSAR), which uses
satellite data to make radar images of a portion of the Earth's surface.
Through this process, images acquired at different times, but from the same
location in space, can be used to detect even minor changes a few
centimeters in the elevation of the ground. The images that reveal the
10-centimeter uplift near South Sister were obtained in 1996 and 2000. The
exact timing of the uplift, or whether it is continuing at present, is
unknown, but is being studied further.
The USGS scientists said the specific cause of the uplift is uncertain, but
because the Three Sisters region is a volcanic area, the uplift may reflect
intrusion of a small volume of magma, or molten rock, deep below the
surface; probably at a depth of about seven kilometers, or four miles.
Such a process, which keeps volcanic areas "alive" and prepares them for
future eruptions, is a common occurrence under volcanoes, but until
development of techniques such as InSAR, it has been difficult to detect.
If intrusion of magma were to continue, it could eventually lead to a
volcanic eruption; however, an eruption is unlikely without significant
precursory activity. In addition to continued or accelerating uplift,
precursors to an eruption would include earthquakes, typically swarms of
small events generated by fracturing of rock as magma moves upward, and
large emissions of volcanic gases, such as carbon dioxide, which are
released from the magma. At present, earthquake activity and gas emissions
appear to be at or near background levels. In order to be prepared to more
accurately detect possible precursors and to better understand this uplift
phenomenon, USGS plans to enhance the existing monitoring network.
Installation of one or more additional seismometers and a Global
Positioning System (GPS) receiver, resurvey of existing benchmarks and
installation of new benchmarks, and periodic airborne and ground-based
sampling of gases are currently being considered in consultation with
managers of the Willamette and Deschutes National Forests.
A number of public officials and agencies in the State of Oregon and Lane
and Deschutes counties have been briefed on these findings and they and
scientists will work together to address any questions or concerns the
public may have.
Additional information on the bulge, including maps and a volcanic-hazards
assessment, may be found on the WORLD WIDE WEB at URL:
http://vulcan.wr.usgs.gov/Volcanoes/Sisters/framework.html
http://volcanoes.usgs.gov/About/What/Monitor/Deformation/InSAR.html
and http://www.geophys.washington.edu/SEIS/PNSN/
Information contacts:
U.S. Geological Survey?Cascades Volcano Observatory, Vancouver, Washington
(360) 993-8900
U.S. Geological Survey?Volcano Hazards Team, Menlo Park, California
(650) 329-5227
Pacific Northwest Seismograph Network, University of Washington, Seattle,
Washington
(206) 685-2255
Oregon Department of Geology and Mineral Industries, Portland, Oregon
(503) 731-4100
The USGS serves the nation by providing reliable scientific information to:
describe and understand the Earth; minimize loss of life and property from
natural disasters; manage water, biological, energy, and mineral resources;
and enhance and protect our quality of life.
* * * USGS * * *
This press release and in-depth information about USGS programs may be
found on the USGS home page: http://www.usgs.gov.
Topic 2 of 99 [Geo]: Vulcanism
Response 398 of 997: Marcia (MarciaH) * Thu, May 10, 2001 (12:54) * 65 lines
***********************
Three Sisters, Oregon
***********************
The Cascades Volcano Observatory is reporting a slight swelling/inflation
in the region of the Three Sisters volcanoes in Oregon, USA sometime
between 1996 - 2000.
Following is from:
http://vulcan.wr.usgs.gov/Volcanoes/Sisters/WestUplift/information_statement
_08may2001.html
Three Sisters, Oregon, Information Statement
May 8, 2001
----------------------------------------------------------------------------
USGS scientists have detected a slight swelling, or uplift, of the ground
surface over a broad area centered 5 kilometers (3 miles) west of South
Sister volcano in the Three Sisters region of the central Oregon Cascade
Range. The Three Sisters region is located 35 kilometers (22 miles) west of
Bend, Oregon, and 100 kilometers (60 miles) east of Eugene, Oregon. The
uplift, which occurred between 1996 and 2000, covers an area about 15 to 20
kilometers (9 to 12 miles) in diameter and the maximum amount of uplift at
its center is about 10 centimeters (4 inches). It is too broad and low to
be noticed from the ground, and several close aerial inspections of the
area have revealed no unusual surface features.
The relatively new technique employed by the scientists, Satellite Radar
Interferometry (or InSAR), uses satellite data to make radar images of a
portion of the Earth.s surface. Images acquired at different times, but
from the same location in space, can be used to detect even minor (a few
centimeters or one inch) changes in the elevation of the ground. The images
that reveal the 10-centimeter uplift near South Sister were obtained in
1996 and 2000. The exact timing of the uplift, or whether it is continuing
at present, is unknown, but is being studied further.
The specific cause of the uplift is uncertain. Because the Three Sisters
region is a volcanic area, the uplift may re flect intrusion of a small
volume of magma (molten rock) deep under the surface-probably at a depth of
about 7 kil ometers (4 miles). Such a process, which keeps volcanic areas
"alive" and prepares them for future eruptions, is a common occurrence
under volcanoes , but until development of techniques such as InSAR, it has
been difficult to d etect. If intrusion of magma were to continue, it could
eventually lead to a volcanic eruption; however, an eruption is unlikely
without significant precursory activity. In addition to continued or
accelerating uplift, precursors to an eruption would include earthquakes,
typically swarms of small events generated by fracturing of rock as magma
moves upward, and large emissions of volcanic gases, such as carbon
dioxide, which are released from the magma. At present, earthquake activity
appears to be at or near background level and gas emissions are low. In
order to be prepared to more accurately detect possible precursors and to
better understand this uplift phenomenon, USGS plans to enhance the
existing monitoring network. Installation of one or more additional
seismometers and a Global Positioning System (GPS) receiver, resurvey of
existing benchmarks and installation of new benchmarks, and periodic
airborne and ground-based sampling of gases are currently being considered
in consultation with managers of the Willamette and Deschutes National
Forests.
A number of public officials and agencies in the State of Oregon and Lane
and Deschutes Counties have been briefed on these findings and they and
scientists will work together to address any questions or concerns the
public may have.
Topic 2 of 99 [Geo]: Vulcanism
Response 399 of 997: Marcia (MarciaH) * Fri, May 11, 2001 (07:57) * 81 lines
Volcano Watch - May 10, 2001
The 1950 eruption of Mauna Loa: a nightmare that could reoccur
On the night of June 1, 1950, after many residents of Ho`okena-mauka
village in South Kona had already gone to bed, Mauna Loa began to erupt.
Soon the roar of the lava fountains could be heard from Highway 11, 24 km
(15 mi) away, as molten lava poured from fissures high on the volcano's
southwest rift zone. In only three hours, an `a`a flow reached the highway
and invaded the village. The streets were lit by flames as lava consumed
several houses and the post office. Thirty-five minutes later, the flow
entered the ocean. By daybreak, lava flows had crossed Highway 11 in two
places, cutting off the only escape route. The villagers all reached
safety unharmed, but for some it was a close call.
Mauna Loa has erupted twice since 1950, with a one-day outbreak at
the summit in 1975 and a three-week eruption on the northeast rift zone in
April 1984.
Most of Mauna Loa's eruptions in the last 150 years began at vents
near the summit. About half of these summit eruptions quickly developed
into flank eruptions along one of two rift zones that extend down its
northeast and southwest slopes. A few eruptions have also originated at
isolated vents on the volcano's northern slope.
The 1984 eruption followed the typical pattern, beginning at the
summit and quickly migrating down the northeast rift zone. Lava flows came
within 6 km (4 mi) of the outskirts of Hilo before the eruption ended.
This eruption paved 41 square kilometers (16 sq mi) of land with lava in
just three weeks, whereas the ongoing eruption of Kilauea that began in
1983 took three years to cover a comparable area. Fortunately, most of the
property buried by lava in 1984 was uninhabited land owned by the state.
Eruptions on the southwest rift zone present a much greater threat to
life and property. The slopes are steep, and residential areas extend from
Highway 11 right up to the rift zone. Although the population has
increased greatly since 1950, the two-lane highway remains the only escape
route.
The good news is that our ability to monitor, and possibly forecast,
the next eruption of Mauna Loa has been greatly enhanced by better
instrumentation. Since 1984, the Hawaiian Volcano Observatory installed
two more seismometers on the southwest rift zone. In the summer of 2000,
three dilatometers, instruments that measure expansion and compression,
were cemented into boreholes 130 m (425 ft) deep on Mauna Loa's flanks.
From 1975 through 1983, measurements of ground deformation near Mauna
Loa's summit indicated slow but persistent inflation. For over a year
prior to the 1984 eruption, the number of earthquakes beneath the summit of
Mauna Loa gradually increased.
If Mauna Loa follows a similar pattern of deformation and seismicity
before the next eruption, we will have a year or so of warning. Since the
rate of inflation has slowed considerably over the past several years and
the seismicity has not increased, we don't think that the next Mauna Loa
eruption is right around the corner. But that doesn't mean we can forget
about it. It means that if we act now, residents and county officials
still have time to prepare for the inevitable.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week. Breakouts from the tube system occur above
Pulama pali and feed multiple flows that are usually tubed over as they
descend Pulama pali. Surface flows are seen throughout the coastal flats,
and the most active area has been beyond the eastern boundary of Hawai`i
Volcanoes National Park near Kapa`ahu. Lava reentered the ocean on May 5
in an area east of Kupapa`u. As of May 10, lava was entering the ocean at
three separate locations spanning about 450 meters (1,500 ft) of shoreline.
One earthquake was reported felt during the week ending on May 10.
Residents of South Kohala felt an earthquake at 4:33 a.m. on the morning of
May 9. The magnitude-3.5 earthquake was located 14 km (8.4 mi) southwest
of Kawaihae at a depth of 21 km (12.6 mi).
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
U.S. Geological Survey
Hawaiian Volcano Observatory
PO Box 51, Hawaii National Park, HI 96718
Phone (808) 967-7328 FAX (808) 967-8890
Topic 2 of 99 [Geo]: Vulcanism
Response 400 of 997: Marcia (MarciaH) * Fri, May 11, 2001 (13:21) * 4 lines
The most complete volcano webcam list with links on the net (watch an eruption from the comfort of your own living room)
http://educeth.ethz.ch/stromboli/livecams/index-e.html
Topic 2 of 99 [Geo]: Vulcanism
Response 401 of 997: Paul Terry Walhus (terry) * Mon, May 14, 2001 (09:42) * 1 lines
That's such a great use of a webcam!
Topic 2 of 99 [Geo]: Vulcanism
Response 402 of 997: Marcia (MarciaH) * Sun, May 20, 2001 (22:44) * 353 lines
Date Thu, 17 May 2001 090624 +0000
From Lisa Koenig
Subject GVP/USGS Weekly Volcanic Activity Report, 9-15 May 2001
GVP/USGS Weekly Volcanic Activity Report 9-15 May 2001
http//www.volcano.si.edu/gvp/usgs/
New Activity/Unrest | Erebus, Antarctica | Etna, Italy | Mayon,
Philippines | Okmok, USA | San Cristobal, Nicaragua | Suwanose-jima, Japan |
Ongoing Activity | Cleveland, USA | Kilauea, USA | Popocatépetl, México |
Shiveluch, Kamchatka | Soufrière Hills, Montserrat | Tungurahua, Ecuador |
*******************
New Activity
*******************
EREBUS Ross Island, Antarctica 77.53°S, 167.17°E; summit elev. 3,794 m
MEVO reported, “harmonic tremor increased dramatically in early 2001 in
association with ash eruptions and lava flows in the inner crater.”
Background. Mount Erebus, the world's southernmost historically active
volcano, overlooks the McMurdo research station on Ross Island. The
3,794-m-high Erebus is the largest of three major volcanoes forming the
crudely triangular Ross Island. The summit of Mount Erebus has been
modified by several generations of caldera formation. A summit plateau at
about 3,200 m altitude marks the rim of the youngest caldera, within which
the modern cone was constructed. An elliptical 500 x 600 m wide,
110-m-deep crater truncates the summit and contains an active lava lake
within a 250-m-wide, 100-m-deep inner crater. The glacier-covered volcano
was erupting when first sighted by Captain James Ross in 1841. Continuous
lava-lake activity has been documented since 1972, punctuated by occasional
Strombolian explosions that eject bombs onto the crater rim.
Source Mount Erebus Volcano Observatory,
http//www.ees.nmt.edu/Geop/Erebus/erebus.html
Mount Erebus Reports
http//www.volcano.si.edu/gvp/volcano/region19/antarct/erebus/var.htm
from the monthly Bulletin of the Global Volcanism Network
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m; All times are
local (= UTC + 1 hour)
The Italy’s Volcanoes website reported that after more than 8 months of
minor activity (slow lava flows, degassing, light ash emission, and
low-level Strombolian activity), a new episode of vigorous volcanic
activity began at Southeast Crater on 9 May. On 6 May active lava flows and
explosions were observed launching pyroclasts and lithics onto the
volcano’s S flank every 7-10 seconds. On 9 May an obvious increase in
activity occurred, with Strombolian bursts occurring every few seconds. By
1745 activity further increased and lava fountains rose up to 100 m above
the NNE flank fissure while a dense eruption cloud simultaneously rose
above the summit vent. Local press sources reported that air traffic was
rerouted during the activity. The high level of activity continued at
Southeast Crater through at least 14 May and strong degassing occurred at
Bocca Nuova crater.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Sources Italy’s Volcanoes, http//www.geo.mtu.edu/~boris/ETNA_news.html,
Charles Rivière's web site
http//perso.club-internet.fr/rivierec/mai_2001.htm
Etna Reports
from
the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev. 2,462
Volcanic activity increased at Mayon, with a lava dome collapse occurring
on 13 May. On 12 May seismographs detected a series of explosions at
Mayon’s summit crater. The following day the SE-facing portion of the lava
dome partially collapsed, leaving a V-shaped opening in the dome. The
collapse produced small lava avalanches that reached a maximum runout
distance of 300 m down the Bonga Gully. After the collapse, incandescence
was observed at the dome and lava fragments fell into the gully. Seismic
activity indicated frequent earthquakes, tremor, and explosions. On 14 May
rockfalls dominated the seismicity. On 15 May there was a lull in
activity, with no rockfalls or lava avalanches occurring. Alert Level 3
remained in effect, prohibiting entry within the 6-km-radius permanent
danger zone. PHIVOLCS warned that lava flows and/or pyroclastic flows could
be produced in the future and residents just outside of the permanent
danger zone should be prepared to evacuate at any time.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Source Philippine Institute of Volcanology and Seismology
http//www.phivolcs.dost.gov.ph/vmepd/vmepd.htm, Associated Press,
http//news.excite.com/news/ap/010514/10/int-philippines-volcano Agence
France Presse http//www.inq7.net/brk/2001/may/15/brkoth_7-1.htm
Mayon Reports
http//www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from
the monthly Bulletin of the Global Volcanism Network
OKMOK Umnak Island, Aleutian Islands, USA, 53.42°N, 168.13°W; summit
elev. 1,073 m All times are local (= UTC - 8 hours)
During ~0800 to at least 1700 on 11 May AVO detected a small earthquake
swarm that was centered near Okmok. Earthquakes in the swarm had magnitudes
of approximately 2-3.6, but their locations could not be pinpointed because
Okmok is not monitored by a local seismic network. AVO noted that the
earthquakes may have been of volcanic origin, but earthquake swarms with
similar sizes and character are not uncommon at Aleutian arc volcanoes and
do not necessarily lead to eruptive activity.
Background. The broad, basaltic Okomok shield volcano, which forms the NE
end of Umnak Island, has a dramatically different profile than most other
Aleutian volcanoes. The summit of the low, 35-km-wide volcano is cut by
two 10-km-wide calderas formed during the Holocene. Numerous satellitic
cones and lava domes dot the flanks of the volcano down to the coast.
Dacitic ash-flow deposits that reach the coast are related to formation of
the two calderas about 8,250 and 2,400 years ago. Some of the post-caldera
cones show evidence of wave terraces; the more recent cones, some of which
have been active historically, were formed after the caldera lake
disappeared. Hot springs and fumaroles are found within the caldera and at
Hot Springs Cone, 20 km to the SW. Historical eruptions have occurred
since 1805 from cinder cones within the caldera.
Sources Alaska Volcano Observatory,
http//www.avo.alaska.edu/avo4/updates/updates.htm
Okmok Reports
http//www.volcano.si.edu/gvp/volcano/region11/aleutian/okmok/var.htm
from the monthly Bulletin of the Global Volcanism Network
SAN CRISTÓBAL Nicaragua 12.702°N, 87.004°W; summit elev. 1,745 m
According to several news reports, INETER stated that beginning on 10 May
there was an increase in seismicity at San Cristóbal and that small
explosions produced plumes composed of gas and small amounts of ash. The
activity continued through at least 13 May. INETER personnel stated that
the level of seismic activity was greater than activity during the December
1999 eruption.
Background. The San Cristóbal volcanic complex, consisting of five
principal volcanic edifices, forms the NW end of the Marrabios Range. The
symmetrical 1,745-m-high youngest cone, San Cristóbal itself (also known as
El Viejo), is Nicaragua's highest volcano and is capped by a 500 x 600 m
wide crater. El Chonco, with several flank lava domes, is located 4 km to
the west of San Cristóbal; it and the eroded Moyotepe volcano, 4 km to the
NE of San Cristóbal, are of Pleistocene age. Volcan Casita, contains an
elongated summit crater and lies immediately E of San Cristóbal; Casita was
the site of a catastrophic landslide and lahar in 1998. The
Plio-Pleistocene La Pelona caldera is located at the eastern end of the San
Cristóbal complex. Historical eruptions from San Cristóbal, consisting of
small-to-moderate explosive activity, have been reported since the 16th
century. Some other 16th-century eruptions attributed to Casita volcano are
uncertain and may pertain to other Marrabios Range volcanoes.
Sources La Noticia http//www2.lanoticia.com.ni/, La Prensa
http//www.laprensa.com.ni/, El Nuevo Diario http//www.elnuevodiario.com.ni/
San Cristóbal Reports <
http//www.volcano.si.edu/gvp/volcano/region14/nicarag/sancrist/var.htm>
from the monthly Bulletin of the Global Volcanism Network
SUWANOSE-JIMA Ryukyu Islands, Japan 29.53°N, 129.72°E; summit elev. 799 m;
All times are local (= GMT + 9 hours)
Beginning on the morning of 9 May volcanic activity increased at
Suwanose-jima when a tremor event commenced. The tremor increased at 1100
and became more violent at 2100. Around noon on 11 May an eruption produced
an ash cloud that rose 1-1.5 km above the crater. The Suwanose-jima Branch
of Toshima village, ~4 km NNW of the active On-take (Otake) crater,
reported that abundant ash fall was observed in the village on 11 May.
Vigorous eruptions on the evening of 12 May and the morning of 13 May
deposited up to 3 cm of ash in the village. At 0900 on 14 May the eruption
seemed to have stopped. The Sakurajima Volcano Observatory reported that
plumes associated with volcanic tremor events have been observed at
Suwanose-jima since the new crater was formed during the December 2000
eruption.
Background. The 8-km-long, spindle-shaped island of Suwanose-jima in the
northern Ryukyu Islands is occupied by a stratovolcano with two
historically active summit craters. Only about 50 persons live on the
sparsely populated island. The summit of the volcano is truncated by a
large breached crater extending to the sea on the E flank that was formed
by edifice collapse. Suwanose-jima, one of Japan's most frequently active
volcanoes, was in a state of intermittent Strombolian activity from On-take
(also called Otake), the NE summit crater, that began in 1949 and lasted
nearly a half century. The largest historical eruption took place in
1813-14, when thick scoria deposits blanketed residential areas, after
which the island was uninhabited for about 70 years. The SW crater
produced lava flows that reached the western coast in 1813, and lava flows
reached the eastern coast of the island in 1884.
Source. Volcano Research Center-Earthquake Research Institute (University
of Tokyo) http//hakone.eri.u-tokyo.ac.jp/vrc/erup/suwa.html , Tokyo VAAC
http//www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
Suwanose-jima Reports
http//www.volcano.si.edu/gvp/volcano/region08/kyushu/suwanose/var.htm
from the monthly Bulletin of the Global Volcanism Network
**************************
Ongoing Activity
**************************
CLEVELAND Aleutian Islands, USA 52.82°N, 169.95°W; summit elev. 1,730
Cleveland was obscured by clouds during most of the week and no thermal
anomalies were observed. AVO had received no reports of significant
volcanic activity from either pilots, residents, or satellite
remote-sensors since the last eruption on 19 March.
Background. The symmetrical Mount Cleveland stratovolcano is situated at
the western end of the uninhabited dumbbell-shaped Chuginadak Island in the
east-central Aleutians. The 1,730-m-high stratovolcano is the highest of
the Islands of Four Mountains group and is one of the most active in the
Aleutians. Numerous large lava flows descend its flanks. It is possible
that some 18th to 19th century eruptions attributed to Carlisle (a volcano
located across the Carlisle Pass Strait to the NW) should be ascribed to
Cleveland. In 1944 Cleveland produced the only known fatality from an
Aleutian eruption. Recent eruptions from Mt. Cleveland have been
characterized by short-lived explosive ash emissions, at times accompanied
by lava fountaining and lava flows down the flanks.
Source Alaska Volcano Observatory
http//www.avo.alaska.edu/avo4/updates/updates.htm
Cleveland Reports
http//www.volcano.si.edu/gvp/volcano/region11/aleutian/cleve/var.htm
from the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Surface lava flows were visible traveling down Pulama Pali. Three
ocean-entry benches were seen along the SE corner of the active lava flow
field. The active lava flow was 300-500 m from the nearest house in the
Royal Gardens subdivision, but the homes may be protected from the lava by
a barrier of `a`a deposited in 1983. Volcanic tremor was higher than normal
during 12 and 13 May and small earthquakes were recorded in the caldera.
Tiltmeters in the summit area and along the east rift zone indicated no
significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source US Geological Survey Hawaiian Volcano Observatory
http//hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http//www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC 6 hours)
CENAPRED reported that at 2301 on 13 May a small explosion sent
incandescent fragments as far away as 0.5 km from the crater. At 0939 on 14
May an ash-and-steam plume rose 1.5 km above the crater.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site) http//www.cenapred.unam.mx/boletines.html
Sources Centro Nacionale de Prevencion de Desastres,
http//www.cenapred.unam.mx/boletines.html, Washington VAAC
http//www.ssd.noaa.gov/VAAC/messages.html
Popocatépetl Reports
http//www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m; All times are local (= UTC + 12 hours)
After a pyroclastic-flow producing eruption occurred at ~0958 on 7 May,
seismic activity decreased but it remained above background levels for most
of the week, a new extrusive dome formed, and the Concern Color Code was
reduced. A noticeable increase in seismic activity occurred between 1820
and 1852 on 7 May, and may have corresponded to an explosion that produced
an ash-and-gas plume. The plume was visible in satellite imagery rising up
to 4 km a.s.l. and drifting ~40 km to the WNW. A small amount of ash fell
in the town of Kliuchi, 46 km from the volcano. During 11-15 May seismic
activity continued to decrease, but remained above background levels. Many
small earthquakes occurred at the volcano’s edifice. At 0900 on 12 May a
new extrusive dome was observed from Kliuchi that was steaming intensely,
100 m high, 200 m wide at the upper part of the dome, and had a volume of
~10 million m3. Observers in Kliuchi reported that by 2140 on 13 May the
dome had grown ~50 m higher. Weak explosions produced ash-and-steam plumes
that rose up to 1 km above the new dome. On 16 May the Concern Color Code
http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
at Shiveluch was reduced from Orange to Yellow.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http//www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
MVO reported that during 4-11 May volcanic activity increased slightly,
with more rockfalls and seismic activity recorded than the previous week
and a small pyroclastic flow on 9 May. The pyroclastic flow traveled ~2.5
km S of the dome down the White River. There still appeared to be a very
small amount of growth in the S side of the lava dome, and observation
flights confirmed that most rockfall activity occurred in the dome’s S
sector. Sulfur dioxide flux remained low.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source Montserrat Volcano Observatory http//www.mvomrat.com/
Soufrière Hills Reports
http//www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m
Heavy rainfall in the vicinity of Tungurahua caused the remobilization of
ash deposited on the upper flanks of the volcano, producing several lahars.
Lahars traveled down the Cusúa, Basural, Mandur, Bascún, and Ulba gorges.
Lahars caused the closing of the Baños-Riobamba highway and blocked a route
to the town of Baños.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted the evacuation of the
town of Baños on the N side of the volcano.
Source Instituto Geofísico, http//www.epn.edu.ec/~igeo/index.html
Tungurahua Reports
http//www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 403 of 997: Marcia (MarciaH) * Mon, May 21, 2001 (17:01) * 7 lines
Mount Rainier at sunset by Diane Lynch
This photo is available for purchase. E-mail The Dispatch.
Eatonville, Washington
Topic 2 of 99 [Geo]: Vulcanism
Response 404 of 997: Marcia (MarciaH) * Mon, May 21, 2001 (23:53) * 132 lines
**********************************
Sheveluch activity, May 20-22(KDT)
**********************************
From: avo-sci@usgs.gov
KVERT Information Release 32-01: May 22, 2001
Kamchatkan Volcanic Activity
INFORMATION RELEASE 32-01
Tuesday, May 22, 2001, 04:00 KDT
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS RED.
PREVIOUS COLOR CODE WAS RED
On May 22, at 2:09 a.m. KDT Sheveluch volcano erupted explosively producing
a mushroom ash column to a height of about 20 km (roughly 65,000 ft.) ASL
(preliminary elevation). The ash cloud is moving south-southeast to the
Pacific Ocean. The lights were observed above the volcano from the town of
Klyuchi. The ash column covered all of the volcano edifice.
KVERT continues to monitor volcano closely.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS.
Vladimir Kirianov
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006, RUSSIA
E-mail: kirianov@kcs.iks.ru
tel. (41522) 58572
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
E-mail: tlmurray@usgs.gov
907-786-7497
================================
KVERT Information Release 31-01: May 21, 2001
Kamchatkan Volcanic Activity
INFORMATION RELEASE 31-01
Monday, May 21, 2001, 10:40 KDT (2140 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Daylight Time, 21 hours ahead of ADT.
KLYUCHEVSKAYA GROUP OF VOLCANOES
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS RED.
PREVIOUS COLOR CODE WAS YELLOW.
On May 21, at 07:13 KDT (at 18:13 UTC on May 20) an explosion at Sheveluch
sent an ash column to an estimated height of 35,000 to 40,000 ft. (10 to 12
km) ASL. A satellite image (via AVO) at 07:50 KDT (18:50 UTC on May 20)
shows a small plume around 15 km long situated above the volcano. A
satellite image at 10:32 KDT (21:32 UTC) shows the plume beginning to move
to the north or northeast. Seismic activity remains above background
levels.
A large thermal anomaly was observed at Sheveluch in satellite images at
18:02 KDT (0502 UTC), and at 18:14 KDT (0514 UTC) on May 20. The first
images has 10 pixels between 30 and 49 dg C, of which 6 pixels are at or
near saturation, the second has 8 pixels between 30 and 40 dg C of which 5
are at or near saturation. Background temperature is 15 dg C for both At
19:25 KDT (06:25 UTC) and at 20:14 KDT (07:14 UTC) on May 20 two explosions
sent an ash column to an estimated height of ~ 15,000 to 16,000 feet (~ 4.7
to 5.0 km) ASL.
KVERT continues to monitor the volcano closely.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS.
Olga Chubarova
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006, RUSSIA
E-mail: ochubarova@emsd.iks.ru
tel. (41522) 58572
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
E-mail: tlmurray@usgs.gov
907-786-7497
================================
KVERT Information Release 30-01: May 20, 2001
Kamchatkan Volcanic Activity
INFORMATION RELEASE 30-01
Sunday, May 20, 2001, 12:20 KDT (0020 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are in Kamchatkan Daylight Time, 21 hours ahead of ADT.
KLYUCHEVSKAYA GROUP OF VOLCANOES
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
PREVIOUS COLOR CODE WAS RED
On May 19, at 04:56 UTC Sheveluch volcano erupted explosively producing an
ash cloud to a height of 33,000 ft. (10 km) ASL. The eruption duration
was about 40 minutes. The ash plume moved to the northeast. The volcano is
now quiet.
KVERT continues to monitor the volcano closely.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS.
Vladimir Kirianov
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006, RUSSIA
E-mail: kirianov@kcs.iks.ru
tel. (41522) 58572
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
E-mail: tlmurray@usgs.gov
907-786-7497
Topic 2 of 99 [Geo]: Vulcanism
Response 405 of 997: Marcia (MarciaH) * Wed, May 23, 2001 (15:27) * 12 lines
ETNA UPDATE
The eruptive activity, which probably attracted the missing Spanish tourist, is continuing without significant variations. Lava is flowing incessantly from one or more vents on the lower NNE flank of the SE Crater cone, at times accompanied by mild spattering. On 15 May, a cluster of three hornitos was observed by Charles Rivière and others, but the next day these had collapsed, leaving a large hollow. On that day lava was issuing from a vent at the base of what remained of the hornitos. While Rivière and his companions were observing and filming the activity, the effusion rate increased, and a new effusive vent became active about 10 m further downslope from the former, yielding a vigorous new flow that was directed NE. The observers also noted an increase in the degassing activity at the main (summit) vent of the SE Crater.
On the same afternoon, Boris Behncke (Dipartimento di Scienze Geologiche of the University of Catania) and three geologists from the Consiglio Nazionale di Ricerca (Rome, Italy) and from Canada approached the effusive vent area from the SE, but was forced to remain at a distance of about 100 m due to a gale-force wind that drove the gas plume from the summit vent of the SE Crater across the ground and thus reduced visibility to a minimum. Loud degassing noises and sporadic explosions were audible in spite of the relentless wind. After descending, the group drove to the village of Fornazzo on the E side of Etna, from where visibility was excellent, especially after nightfall. The active lava flow was perfectly visible, extending in at least three lobes to the NE and E. More impressively, the summit vent of the SE Crater produced Strombolian explosions that sent incandescent bombs up to 100 m into the sky, and some fell onto the flanks of the cone. These explosions appeared to be clustered, there would be a r
latively quiet period lasting up to 15 minutes, after which a series of explosions occurred in the course of about 10 minutes. The strongest burst was observed at about 2100 h, which was directed obliquely to the S or SE and dropped a significant amount of glowing pyroclastics on the upper SE flank of the cone.
18 May 2001 update. NOTE: There will be no updates on this page until 26 May due to a week-long excursion to Etna organized by the Open University Geological Society
The Spanish tourist from Madrid, Beatriz Caldevilla Lebena, who had disappeared on Etna four days ago, is presumed dead after remains of her tent were found on 18 May near the rim of the Bocca Nuova, one of the four summit craters of Etna. Press sources cite rescue team members who found footprints leading from the tent to the rim of one of the two active pits within that crater, but no footprints leading back from there. It is possible that the woman went to look into the pit on the evening of her arrival at the summit and fell into it when a portion of its rim broke loose.
Meanwhile the effusion of lava from the vent (or vents) on the NNE flank of the SE Crater cone is continuing. The active lava was well visible during the night of 17-18 May, and possibly there was also weak Strombolian activity at the summit vent of the SE Crater. The active lava flow advanced in several branches, the longest of which was almost 2 km long (information from Giuseppe Scarpinati).
Topic 2 of 99 [Geo]: Vulcanism
Response 406 of 997: Marcia (MarciaH) * Thu, May 24, 2001 (22:59) * 112 lines
******************
Japanese updates
******************
Based on information from
http://hakone.eri.u-tokyo.ac.jp/vrc/erup/erup.html, maintained by S.
Nakada of the University of Tokyo. The caldera-forming collapse at
Miyakejima apparently ended in Sept. 2000. The last eruptive event known
was that of 19 March 2001 (small ash eruption from the new caldera).
However, observations on 5 May 2001 show gas plumes rising continuously to
2,000m with very high SO2 rates of 33,000 - 46,000 metric tons/day.
Earthquake swarm on 7 May 2001. Meanwhile, Fuji's high rate of seismicity
ended in January of 2001, although 30 April did see 67 earthquakes,
centered NE of the summit. And the island volcano of Suwanosezima continues
to erupt from the craters formed in December, with eruptions on 9-13 May
with ash clouds to 1,000 - 1,500 m above the crater with local ash falls,
volcanic tremor and audible effects.
*******************************************************************
The following Miyakejima report is from:
http://hakone.eri.u-tokyo.ac.jp/vrc/erup/miyake.html
MIYAKEJIMA VOLCANO, South of Tokyo
(Oyama 813 m, 34o04'43"N, 139o31'46"E)
(05/11/01)
According to JMA's Weekly Reports and Volcano Observation Reports on the
volcanic activity on Miyakejima, a plume of steam including abundant SO2
had been continuously emitted from the summit caldera as high as 500 to
2,000 m above the rim. Gray-colored cloud had not been observed since the
19 March morning, when a small-scale eruption probably took place, being
associated with tremor events and following acoustic signals of the
previous night. GPS of JMA showed steady continuous shrinkage of the
volcano, though the rate was lower than before last September.
Though a low level of seismicity had continued in Miyakejima, the quake
with M2.8 occurred at 02:18 on 7 May. No any other manifestation of the
activity was observed before and after the quake. Four
hundred-and-forty-six of small low-frequency earthquakes occurred on May 5.
COSPEC analysis by JMA indicated still continuous emission of SO2 as
abundant as 33,000 to 46,000 ton a day.
Geologists of universities and Geological Survey of Japan had continued the
air inspection, three times a week, who are flying from Tokyo. Very small
collapses of the caldera rims occurred rarely, but the caldera scale had
hardly increased since last September.
*******************************************************************
The following Fujiyama report is from:
http://hakone.eri.u-tokyo.ac.jp/vrc/erup/fuji.html
FUJI VOLCANO, central Japan
(3,776m, 35o21'27"N, 138o43'50"E)
(May 11, 2001)
According to JMA, the daily number of earthquakes in Mt. Fuji was 67 on 30
April; highest since 18 December 2000 (53 times), though the seismic
activity had been relatively low since January. The weekly number of
earthquakes (May 3-9) was as high as 130. Most of these earthquakes were of
low-frequency type, which took places at about 15 km-depth just northeast
of the summit. The monitoring system of National Research Institute for
Earth Science and Disaster Prevention (NIED) had not detected any other
anomalous signs in this volcano.
*******************************************************************
The following Suwanosezima report is from:
http://hakone.eri.u-tokyo.ac.jp/vrc/erup/suwa.html
SUWANOSE-JIMA VOLCANO, SW Islands, Kyushu
(29o52'38"N, 128o13'28"E)
(May 14, 2001)
According to the Suwanose-jima Branch of Toshima-Village, whose main office
is in a different island, reported that falling of abundant ash was
observed around 08:45 on 11 May in the village about 4 km NNW of the active
crater (Otake), such that cars could not run without dusting the front
windows. The eruptions that occurred during the 12 May evening to the 13
May morning were vigorous, and ash deposition was as thick as 3 cm in the
village. At 06:30 on 13 May, still erupting but neither sound nor
vibration. It seemed not to be erupted at 09:00 on 14 May, and cleaning of
ash deposits from the roads started in the village.
Information contact: JMA; n-uchida@met.kishou.go.jp, and VRC:
nakada@eri.u-tokyo.ac.jp
(May 11, 2001)
According to Sakurajima Volcano Research Center (Sakurajima Volcano
Observatory) of Disaster Prevention Research Institute, Kyoto University,
eruption plumes had been observed in Suwanosejima volcano, being associated
with volcanic tremor events, since the eruption of last December that
formed new craters. A tremor event started on the May 9 morning, and the
number of events increased since 11 a.m. The events moved into more violent
activity associated with acoustic signals around 9 p.m. Such the activity
is first since June 1999. Compared with a highly active period before 1995,
the amplitude of acoustic signals and the number of occurrence are small.
SVRC was calling people's attention to the volcanic activity that may
become more explosive.
JMA issued the Volcano Observation Reports #3 and #4 on this volcano on 10
and 11 May, respectively. They include the reports from the Toshima Village
officials; the height of gray-colored eruption column was rising about
1,000 to 1,500 m above the crater around the 11 May noon, and ash falling
was observed. No felt earthquake reported.
Topic 2 of 99 [Geo]: Vulcanism
Response 407 of 997: Marcia (MarciaH) * Fri, May 25, 2001 (13:40) * 49 lines
Kamchatkan Volcanic Activity
Thursday, May 24, 2001, 13:00 KDT (0000 UTC)
The following Release was received by the Alaska Volcano Observatory
via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are in Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
PREVIOUS COLOR CODE WAS RED
On May 22, at 2:09 a.m. KDT (13:09 UTC on May 21) Sheveluch volcano
erupted explosively producing a mushroom-shaped ash column to a height
more than 10 km (more than 33,000 ft.) ASL. The ash cloud moved to the
south-southeast, and lights were observed above the volcano from the
town of Klyuchi (45 km south of the volcano). At 3:36 KDT an
asymmetrical fan-like ash cloud moved slowly east. At 8:30 KDT on May
22, a gas emission to a height of 2000 m above the dome was observed.
According to the report from the town of Klyuchi, the new dome (first
observed on May 12) and the western part of old dome were destroyed.
According to GMS satellite imagery at 14:32 KDT (0132 UTC) on May 22,
the eruption cloud from the 1309 UTC explosion
continued to diffuse over the Kliuchevskoi Group (near the center of
the Kamchatka Peninsula). The estimated size of the plume was
approximately 50,000 km^2. The high-pressure system over northern
Kamchatka caused the plume to remain fairly stationary over the
region.
At 16:30 KDT (03:30 UTC) on May 22 ash-gas explosions to a height up
to 1500 m above the dome were observed. On May 23, a gas and steam
plume rose 400-800 m. A large thermal anomaly was observed at
Sheveluch in satellite images at 16:55 KDT (0355 UTC) and 17:39 KDT
(04:39 UTC) on May 23. The images show approximately 10 pixels ranging
from 30 to 49 degrees Celsius, with 2 pixels at or near saturation.
The shape of the anomaly is elongate to the south and may represent a
pyroclastic flow from the dome area.
On the morning of May 24, a gas and steam plume was observed rising
1200 m above the dome. Seismic activity remains above background
levels. Earthquakes with a magnitude Ml=2-3 and many small earthquakes
within the volcano's edifice were recorded. Since May 20, earthquakes
located at depths near 5 km have begun to be registered again for the
first time since May 11.
KVERT continues to monitor volcano closely.
Topic 2 of 99 [Geo]: Vulcanism
Response 408 of 997: Marcia (MarciaH) * Fri, May 25, 2001 (13:42) * 84 lines
************************
Kilauea Eruption Update
************************
Volcano Watch - May 24, 2001
An exciting couple of weeks at Kilauea
The last couple of weeks have been exciting ones to be studying
active volcanism in Hawai'i. To start with, after several months of fairly
constant effusion of lava and gas, emissions of sulfur dioxide gas (SO2)
doubled, seemingly overnight, then tripled over the next few days. The SO2
that is eventually released from Kilauea is dissolved in the magma--like
gas bubbles dissolved in champagne. Increased gas emissions from the magma
are usually associated with an increased supply of magma to the eruption.
Sure enough, the increased gas emissions observed over the past weeks were
accompanied by renewed pond activity within Pu'u 'O'o's crater for the
first time in months, indicating that more magma was moving through the
system.
Last Sunday evening, several of the staff from HVO and the National
Park had an impromptu gathering at the observatory to puzzle over Kilauea's
latest developments. It had been an exciting afternoon; within a little
over an hour-much less time than even a Kilauea heartbeat-- a tiltmeter at
the summit of the volcano near HVO suggested that a volume of up to four
million cubic meters (mcm), (five million cubic yards (mcy)) of excess
magma had entered and inflated the summit magma reservoir of the volcano.
For perspective, a ready-mix truck holds about seven cubic meters (nine
cubic yards) of concrete.
About 20 minutes later, Pu'u 'O'o cone also began swelling in a
similar manner. While this was happening, the magnitude of seismic tremor
(very low-level ground shaking associated with magma movement) beneath the
summit and Pu'u 'O'o increased as well. We were impressed by the four mcm
(five mcy) of magma, because this is a typical amount supplied to the
eruption over the course of ten days-- not an hour! Among our several
questions was: "If this much excess magma was intruding the summit
reservoir and not being erupted, where would it go within the volcano, and
what would happen next?"
In nearly as short a time period as the inflation had occurred, one
of our questions was answered. The summit tilt reversed, and a few hours
later, instruments located on the rim of Pu'u 'O'o indicated that new lava
was pouring onto its crater floor. Inflation and tremor at the cone and
beneath Kilauea's summit subsided thereafter, and the HVO staff decided to
go home and get some sleep. The pressure was literally off, or at least
relieved.
By the next day (Monday), eruptive activity and gas emissions from
the east rift seemed to be returning to normal. On Tuesday, however, no
lava was visible except that draining from tubes at the coast, and we
thought the eruption might be heading into a pause. This turned out to be
only a temporary slow-down, not a stoppage. By Wednesday morning, lava had
reappeared on Pulama pali, and by the afternoon, field crews reported
vigorous breakouts of lava above the pali between the 2,300 - to 2,200-
foot elevations.
This is hardly the end of even this episode of the story. As of this
writing, Thursday afternoon, one of our original questions of last Sunday
night remains: Where did the four million cubic meters (five mcy) of excess
magma go? Although we did see increased lava effusion at Pu'u 'O'o and on
the flow field, we are confident that the amount of lava erupted over the
last week was much less than this. And so, if you happen upon an extra
several million cubic meters of magma (several million cubic yards), it
should still be hot, so don't touch it, but please return it to Kilauea.
Some of us are still looking for it. But most likely, you won't find it,
because it is probably stored below Pu'u 'O'o in space made available as
the south side of Kilauea moves away from the rest of the volcano.
Eruption Update
As mentioned above, eruptive activity of Kilauea Volcano fluctuated
during the past week, and the volume of lava entering the ocean east of
Kupapa`u reflected this fluctuation. The surge in lava production on
Wednesday overwhelmed the tube system and resulted in three major
breakouts. Surface flows provide visitors at the end of the Chain of
Craters road in Hawai`i Volcanoes National Park a great display of lava
cascading down Pulama pali.
One earthquake was reported felt during the week ending on May 24. A
resident of Pahala felt an earthquake at 4:26 p.m. on May 24. The
magnitude-3.2 earthquake was located 4 km (2.4 mi) east of Pahala at a
depth of 10.7 km (6.4 mi).
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
U.S. Geological Survey
Hawaiian Volcano Observatory
PO Box 51, Hawaii National Park, HI 96718
Topic 2 of 99 [Geo]: Vulcanism
Response 409 of 997: Marcia (MarciaH) * Mon, May 28, 2001 (23:40) * 3 lines
Test for Pyrocastic flow - Rob this one's for you!
Topic 2 of 99 [Geo]: Vulcanism
Response 410 of 997: Marcia (MarciaH) * Tue, May 29, 2001 (20:15) * 52 lines
*********************************
AVO Weekly Update: May 25, 2001
*********************************
From: avo-sci@usgs.gov
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, May 25, 2001 10:30 AM AST (1830 UTC)
CLEVELAND VOLCANO (CAVW #1101-24)
52o49'N 169o57'W Summit Elevation 5,674 ft (1,730 m)
No further eruptive activity has been reported or detected at Cleveland
Volcano, and no thermal anomalies have been observed at the volcano over
the past 6 weeks. As such, AVO will stop detailing activity at Cleveland
in these updates unless new activity is detected or reported.
OKMOK VOLCANO (CAVW # 1102-29)
53o24'N 168o10'W Caldera rim elevation 3520 ft (1,073 m)
The earthquake swarm centered near Okmok Volcano, first detected on May 11,
has ended. No additional earthquakes have been detected in the region for
the past 10 days. As such, AVO will stop detailing activity at Okmok in
these updates unless new activity is detected or reported.
OTHER ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
all at or near normal levels of background seismicity. AVO did not detect
ash plumes or significant elevated surface temperatures in the vicinity of
any volcano.
Abbreviated Color Code Key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of Alaska's volcanoes (907) 786-7478
Topic 2 of 99 [Geo]: Vulcanism
Response 411 of 997: Marcia (MarciaH) * Thu, May 31, 2001 (00:06) * 113 lines
*************************************************
Origins, Emissions and Impacts of Volcanic Gases
*************************************************
From: Clive Oppenheimer
Origins, emissions and impacts of volcanic gases
A Flagship meeting of the Geological Society of London, held in memory of
Peter Francis
Thursday 25th and Friday 26th October, 2001
The Geological Society, Burlington House, London
Rationale for the meeting
Volcanoes emit gases both during and between eruptions. Their impacts on
the atmosphere, climate and environment are strongly controlled by fluxes
and emission altitudes of halogens, and SO2, which forms sulfate aerosol.
Episodic explosive eruptions are the principal perturbation to
stratospheric aerosol. In the troposphere, the picture is less clear but
recent analyses suggest that up to 40% of the global tropospheric sulfate
burden may be volcanogenic. Sulfate aerosol influences the Earth's
radiation budget by scattering and absorption of shortwave and longwave
radiation, and by seeding or modifying clouds. When they are deposited at
the Earth's surface, volcanic sulfur and halogens can result in profound
environmental impacts.
Surveillance of gas composition and flux is also essential for
interpretation of volcanic activity, since the nature of degassing exerts a
strong control on eruption style, and is closely associated with volcano
seismicity and ground deformation. Unfortunately, the modelling frameworks
for interpretation of geochemical data are only poorly developed, limiting
the application of such data in hazard assessment. The aims of this
discussion meeting are to bring together experts in several fields to
examine critical issues in the observation and modelling of volcanic
degassing and its atmospheric and environmental consequences.
Specifically, it aims to:
* Explore the development and validation of comprehensive physico-chemical
models for volcanic degassing by integrating results from experiments on
synthetic and natural melts, analysis of dissolved volatiles preserved in
melt inclusions, and observed volcanic gas geochemistry.
* Consider how such models can be applied to integrated geophysical,
geodetic and geochemical monitoring data to support eruption forecasting.
* Explore the development of quantitative models for the transport and
chemistry of volcanic plumes, and to consider the potential impacts of
future large magnitude eruptions on the atmospheric and terrestrial
environments (including urban and rural environment).
Speaker programme
Patrick Allard, CEA-CNRS, Gif
Magma degassing processes at Stromboli and Etna: constraints from melt
inclusions and volatiles fluxes
Mike Carroll, Universitá di Camerino
Behaviour of halogens during magma ascent and eruption
Pierre Delmelle, Université catholique de Louvain
Atmospheric dispersion, subsequent deposition and environmental effects
associated with the low-altitude gas plume emitted from Masaya volcano,
Nicaragua
Terry Gerlach, US Geological Survey
CO2 degassing at K+lauea Volcano: implications for primary magma, summit
reservoir dynamics and magma supply monitoring.
Don Grainger, University of Oxford
Atmospheric effects of volcanic eruptions
Hans Graf, Max Planck Institute for Meteorology, Hamburg
Simulating volcanic plumes: From micro to large scales
Lisa Horrocks, Met Office, UK
Compositional variation in tropospheric volcanic gas plumes: evidence from
ground-based remote sensing
Paolo Papale, Istituto Nazionale di Geofisica e Vulcanologia, Pisa
Physical modelling of volatile solubility in magmas, and applications to
degassing and eruption dynamics
Bruno Scaillet, ISTO, Orleans
Experimental constraints on H2O and sulfur abundances in arc magmas and
implications for degassing processes
Steve Self, The Open University
Fissure and flood basalt eruptions: potential impact on the atmosphere and
climate
Steve Sparks, University of Bristol
Coupling of eruption dynamics and degassing at the Soufriere Hills Volcano,
Montserrat
Call for papers
We encourage poster contributions on any aspect of volcanic degassing, but
especially on:
* The integration and interpretation of geophysical, geodetic and
geochemical data.
* The potential for combining experimental, theoretical and empirical
approaches to generic models for volcanic degassing.
* The atmospheric transport, chemistry, radiative effects, deposition, and
ultimate environmental impacts of volcanic gases and aerosols (including ash).
The deadline for abstracts (which may be forwarded electronically to any
member of the scientific committee listed below) is 31st May 2001. It is
hoped that publication of a Special Memoir of the Geological Society will
arise from this meeting. Please indicate if you wish to contribute a
manuscript - the deadline for submission of full manuscripts will be the
26th October, 2001.
Further details are available at:
http://www.geolsoc.org.uk/template.cfm?name=VMSGFrancisMemorial
For registration details, please contact the Conference Office of The
Geological Society, helen.wilson@geolsoc.org.uk or
jennifer.last@geolsoc.org.uk
Scientific committee
Clive Oppenheimer
Department of Geography, University of Cambridge, Downing Place, Cambridge
CB2 3EN, UK
co200@cam.ac.uk
Jenni Barclay
School of Environmental Sciences, University of East Anglia, Norwich NR4
7TJ, UK
J.Barclay@uea.ac.uk
David Pyle
Department of Earth Sciences, University of Cambridge, Downing Street,
Cambridge CB2 3EQ, UK
dmp11@esc.cam.ac.uk
Topic 2 of 99 [Geo]: Vulcanism
Response 412 of 997: Marcia (MarciaH) * Thu, May 31, 2001 (18:13) * 28 lines
Recent Volcanic Ash Eruptions:
Ash data is summarized from the weekly GVN/USGS report
http://www.nmnh.si.edu/gvp/usgs/index.htm
All ash elevations are in km above sea level.
Ash elevations of 5 mi/8 km are highlighted in red.
United States, Hawaii, KILAUEA, summit elev. 1222 m
Lava entering the ocean on 23 May
Mexico, POPOCATEPETL, summit elev. 5426 m
Small-to-moderate sized exhalations, on 26 May steam-and-ash to 7 km
Nicaragua, MASAYA, summit elev. 635 m
on 23 May volcanic "smoke" and steam.
Montserrat, West Indies, SOUFRIÈRE HILLS, summit elev. 1052 m
during 19 to 21 May convective ash clouds to less than 2 km
Ecuador,
TUNGURAHUA, summit elev. 5023 m
on 26 May ash to 7 km, on 30 May ash to 8.2 km
GUAGUA PICHINCHA, summit elev. 4784 m
on 25 May steam-and-ash to 8.5 km
Russia, Kamchatka, SHIVELUCH, summit elevation 3283 m; (data revision)
On 22 May eruption to 10 km, then several small eruptions with ash-and-gas to 2 km
Japan, MIYAKE-JIMA Izu Islands, summit elev. 815 m
steam plumes continuously to 1.3-2.8 km
Philippines, MAYON, summit elev. 2462 m
On 28 May an ash puff
Italy, Sicily, ETNA, summit elev. 3315 m
through 25 May mild Strombolian activity
Topic 2 of 99 [Geo]: Vulcanism
Response 413 of 997: Marcia (MarciaH) * Fri, Jun 1, 2001 (16:16) * 51 lines
Analytical, Computational and Experimental (ACE) Studies in Earth Sciences
*******************************
Marie Curie ACE Training Site
*******************************
From: Patrice Hornibrook
Analytical, Computational and Experimental (ACE) Studies in Earth Sciences
Are you working on your Ph.D.? Would your Ph.D. research benefit from
resources unavailable to you at your home university? Did you know you
could be paid to travel to and work at a Marie Curie Training Site on
aspects of your Ph.D.? ACE Bristol (http://mcts.gly.bris.ac.uk) may be the
programme for you!
Applications are invited from Ph.D. students from EU member and Associated
States* (excluding UK) for research training at the ACE Earth Sciences
Training Site. The Site is hosted by the University of Bristol and funded
by the European Commission program 'Improving Human Research Potential and
the Socio-economic Knowledge Base'. Training is available in modern
analytical, computational and experimental methodologies in four core areas
of Earth Sciences:
Geochemistry
Experimental and theoretical studies of the earth's interior
Volcanology and geological fluid dynamics
Palaeontology
Students undertaking studies in one of the above disciplines will be
supervised and trained in their respective fields by experienced staff
including Professors M.J. Benton, D.E.G. Briggs, C.J. Hawkesworth, R.S.J.
Sparks and B.J. Wood. Students may also (as required) be enrolled in
specialist courses in their field of research and in communication skills.
The goal for visitors will be to submit a manuscript in English to an
international Earth Science journal by the end of their stay. Visitors
will have full access to departmental student resources including excellent
libraries and to the analytical facilities which are contained in the EU
Geochemical Facility: electron probe microanalysis, ICP-MS, Laser Ablation
ICP-MS, ICP-AES, TIMS, Mössbauer (Fe3+/Fe2+), FTIR (CO2 & H2O), LECO (bulk
C & S), XRF, XRD, NMR, SEM-EDS. UNIX workstations are available for a wide
range of statistical and modelling studies.
Between 5 and 7 students per year will benefit under this scheme. Visits
can last between 3 months and one academic year. The host will provide
travel and subsistence expenses. Applicants are strongly advised to discuss
their requirements with Bristol staff prior to sending in their
applications. The next deadline for applications is 30th June 2001. Further
information, eligibility criteria and application forms can be downloaded
from:
http://mcts.gly.bris.ac.uk
Topic 2 of 99 [Geo]: Vulcanism
Response 414 of 997: Marcia (MarciaH) * Fri, Jun 1, 2001 (18:50) * 47 lines
*****************************
Canadian volcanology website
*****************************
From: "Stasiuk, Mark"
Announcing the launch of volcanocanada.com, a website about Canadian
volcanology and the young volcanoes of Canada. The site was built and will
be maintained by the Geological Survey of Canada, Pacific Division
(Vancouver), and can also be reached via the GSC website on earth sciences:
http://www.nrcan.gc.ca/gsc/pacific/vancouver/earthsci/index_e.htm
(follow the link on the side bar for volcanoes)
The site was initially launched last week and is a "beta" version. It is
currently being translated to French and being looked over for errors and
navigational glitches. The translation could take some time as there are
more than 600 html files! The site includes a number of general sections on
volcanology and volcanic hazards, information on what we do at the GSC, a
section for students on how to become a volcanologist, a list of links to
related sites, and a large section giving specific information on more than
250 Canadian volcanoes and volcanic features. The specific information comes
in two forms: a simple html catalogue, and interactive maps which allow you
to reach shaded-topography DEM images of most of the volcanoes.
The site will undergo significant additions on an approximately 6-month
frequency.
I hope you'll take a few minutes and check it out. Feel free to provide me
with suggestions for changes and additions - for example if you want us to
add a link to your site. Also, where relevant please add a link to us from
your site. Email me either at mstasiuk@nrcan.gc.ca, or volcano@nrcan.gc.ca
Dr. Mark V. Stasiuk
Volcanologist
volcanocanada.com
Natural Resources Canada
Geological Survey of Canada, Pacific Division www.nrcan.gc.ca/gsc
101 - 605 Robson Street, Vancouver, B.C., Canada, V6B 5J3
tel. (604) 666-0529 (reception), (604) 666-2997 (direct)
fax (604) 666-1124, email mstasiuk@nrcan.gc.ca
Topic 2 of 99 [Geo]: Vulcanism
Response 415 of 997: Marcia (MarciaH) * Sat, Jun 2, 2001 (16:05) * 6 lines
To the Kraffts and the rest who lie beneath the pyrocasts of Unzen, Aloha!
Topic 2 of 99 [Geo]: Vulcanism
Response 416 of 997: Marcia (MarciaH) * Sat, Jun 2, 2001 (18:37) * 6 lines
And, thanks for letting me borrow your photo, Rob... it is splendid of Unzen!
This is the eruption that claimed so many geologists and volcanologists. Has it been 10 years?!
Topic 2 of 99 [Geo]: Vulcanism
Response 417 of 997: Rob Glennie (AotearoaKiwi) * Sun, Jun 3, 2001 (02:39) * 6 lines
Hi
Ten years ago today, part of the lava dome on the summit of the Japanese volcano Unzen collapsed. The resulting pyroclastic flow which was unusually large, poured down a valley in which journalists, volcanologists and local people were watching the volcanic activity, and killed them. The Japanese army, I think, pulled 38 corpses out after that eruption and 5 more out a couple days later when another flow caught more people by surprise.
Three volcanologists (Maurice + Katia Krafft, plus Harry Glicken)were killed in the deadly June 3 event, now world famous for the footage of the man and the vehicle fleeing the volcano.
Rob
Topic 2 of 99 [Geo]: Vulcanism
Response 418 of 997: Marcia (MarciaH) * Sun, Jun 3, 2001 (13:56) * 8 lines
Rob, I am still looking for the stills from that video, if they exist, to post. Meanwhile, here is a totally different view of the pyroclastic flow from http://www.iaag.geo.uni-muenchen.de/sammlung/Unzen.html
Topic 2 of 99 [Geo]: Vulcanism
Response 419 of 997: Marcia (MarciaH) * Mon, Jun 4, 2001 (17:23) * 45 lines
Since he did not post it here, I am going to borrow Rob's comments and risk his wrath since I did not get his permission. I am good about doing this but in this case it is so timely it needs to be posted now.
Today is the tenth anniversary of the 1991 Unzen-dake eruption. Unzen
awoke in late 1990 with small quakes underneath the dome that started
rising toward the summit. Despite the earthquakes and plumes of steam
rising of the dacitic dome, the volcano did not appear all that
threatening. However anyone who knows the volcano knows that in 1792 there was a
debris slide and tsunami that killed 15,000 people.
Maurice and Katia Krafft went to Japan after Maurice picked up a phone
call from Japan about the volcano awakening. He phoned a friend, saying
"we are about to Japan to zee a volcano that is "very" interesting."
This was the last that anyone outside of Japan heard of them. It would
appear that they reached the volcano and chose a spot away from where the
pyroclastic flows that Mount Unzen was letting of, were going. But
sometime on the morning of June 3, 1991 there was a deafening bang
(survivors report - source unknown)and part of the dome collapsed. A large
pyroclastic flow rushed down the valley (it covered the entire valley floor
and the slopes on both sides). The Kraffts had initially appeared to
have escaped the flow as it surged past them, but the survivors say there
was a shift in the wind direction. The flow turned straight toward the
Kraffts position from which there was no way out. The rest is history.
See Savage Earth (National Geographic documentary)for more. No mention
of Harry Glicken. So I do not know if he tried to run or was caught off
guard. Large pyroclastic flows continued the following day and
throughout the rest of the month of June. A 44th victim was added to
the fatality list on June 23 1991.
ROBS ADVICE:
Lava domes earn my highest respect because of the instantaneous
chemical reaction between the gas filled magma underneath and the air. The
explosions of these domes are some of the deadliest in the world and even
if there is no steam rising off a lava dome on an active volcano, if
the dome is steeper than 42 degrees, get out fast. Do not stop for
anything least of all photo shots, if you don't want to die on a volcano.
Rob
from http://clubs.yahoo.com/clubs/worldvolcanism
Maurice and Katia Krafft
Topic 2 of 99 [Geo]: Vulcanism
Response 420 of 997: Rob Glennie (AotearoaKiwi) * Mon, Jun 4, 2001 (18:54) * 7 lines
Hi
My e-mail is called lava.dome because although it is very rare I do occasionally let fly with a pyroclastic flow in there. But no explosions, dome collapses or anything like that when they are unwarranted, though I would hope the very mention of a pyroclastic flow in this message will encourage better acknowledgement. The worst I can do is unleash an explosion - to do that you have to push me over the edge by ignoring the many warnings I will issue.
Hugs Rob
(you are not in trouble unless you stop acknowledging material you use that I made up)
Topic 2 of 99 [Geo]: Vulcanism
Response 421 of 997: Marcia (MarciaH) * Tue, Jun 5, 2001 (13:52) * 1 lines
Rob, Luv, I always give credit and cite sources. It is not only the scientific thing to do, it protects your intellectual output. Besides, you said it so much better than I could have. Your piece is a great tribute to those who became part of the volcano in one earth-changing instant. I trust and will try ever so hard not ever to cause anything but smiles and thoughtful comments from you. *Hugs*
Topic 2 of 99 [Geo]: Vulcanism
Response 422 of 997: Neil Hodgins (ThinkingManNeil) * Tue, Jun 5, 2001 (19:54) * 70 lines
Sometime ago, I read in a tourist guide to the interior of British Columbia that the town of Rossland is built in the crater of an ancient volcano. I was fascinated by this, but could find little else to corroborate it other than the town's own website, http://www.rossland.com , which reiterated the claim. Marcia was kind enough to point me to a new website for Canadian Volcanoes; so I sent an inquiry into the alleged volcanic history of the Rossland area, and this was the reply I got:
hello Neil,
thanks for your message.
Rossland's most definitely not built in the crater or caldera of an ancient
volcano. It's geology is fairly old by active volcano standards, with the
youngest rocks being about 40 million years old. Those rocks are indeed
volcanic, and form a thick pile just west of Rossland (e.g. OK Mountain,
Roberts Mtn.) which runs sort of north-west. The pile is cut by faults and
deeply incised by erosion, so it's original extent and full relations --
which would have allowed me to say much more about it's volcanic history --
are largely hidden. The next oldest rocks go back to the 60 to 200 million
year period, and are dominantly granites. These are the sorts of rocks that
Rossland is built on. They are cut by "thrust" faults that formed in
response to tectonic forces ramming in from the west, pushing up the
Rockies. The granites represent magma chambers that might have been the
source zones for volcanoes in the 100 to 200 million year range but have
since been completed removed by erosion. Granites don't always act as root
zones for volcanoes, sometimes they intrude the crust and never produce
eruptions.
The ~40 million year old volcanic rocks are lava deposits called andesite
that are typical of tectonic subduction zone volcanoes. They were erupted
when the coastline was further east than now. As the western parts of BC
have been added to, the coast has stepped westward and so has the line of
active volcanoes. The volcanic rocks left behind, to the east of the coast,
got eroded and faulted with time.
There's no clear definition of an extinct volcano, but generally it's one
that shows no signs of activity now or historic time, it's last eruption was
hundreds of thousands or more years ago, and it is no longer in an area of
active tectonics that could produce magma to feed future eruptions. The
definition is problematic because some dormant volcanoes show few signs of
activity, erupt very infrequently, and some apparently "tectonically dead"
regions get very infrequent and poorly understood eruptions. In the case of
the Rossland volcanics, however, the great age and tectonic location, plus
the lack of volcanic-related hotsprings or seismic activity, indicate the
area's volcano is very much extinct.
best regards,
Mark Stasiuk
----------
From: Main Web Server[SMTP:webserve@nrn1.NRCan.gc.ca]
Sent: Saturday, June 02, 2001 6:17 PM
To: volcano@nrcan.gc.ca
Subject: Other: Sat. June 02, 2001
Neil Hodgins
neil_hodgins@hotmail.com
Hello;
I've had an interest in volcanoes for many years, and I'm glad to
finally see a site that\'s dedicated to the Canadian aspect of the field.
I had a question about an extinct (?) volcano that doesn't appear on your
map of BC. I've read that the town of Rossland, BC, is built in the
crater (caldera?) of an ancient volcano (the town's website,
http://www.rossland.com even makes mention of it). I've looked for more
information on this volcano, but have found no mention of it. Could you
tell me a little more about the geology and eruptive history of this site,
if it is indeed a volcano? Also, by what criteria is a volcano considered
to be extinct? Is it based solely on time between eruptions, or is there a
physical aspect such as erosion of the magma chamber?
Thanks,
Neil H.
PS. Very nice site you have here--well laid out and very informative. Info
on the T'seax eruption was especially interesting.
Topic 2 of 99 [Geo]: Vulcanism
Response 423 of 997: Marcia (MarciaH) * Tue, Jun 5, 2001 (20:00) * 1 lines
Thanks Rob and *Hugs* for going to all that trouble. You got more than just a polite brush off answer. Too bad the Rossland site guys did not do their own homework! Fascinating. I wonder what the source of the incorrect information was. Makes one wonder about cross checking anything I post. As always, it i more important for me to get the correct information out than to be "right" all the time. Input is vital and I appreciate each and every comment and correction.
Topic 2 of 99 [Geo]: Vulcanism
Response 424 of 997: Neil Hodgins (ThinkingManNeil) * Tue, Jun 5, 2001 (20:01) * 70 lines
Sometime ago, I read in a tourist guide to the interior of British Columbia that the town of Rossland is built in the crater of an ancient volcano. I was fascinated by this, but could find little else to corroborate it other than the town's own website, http://www.rossland.com , which reiterated the claim. Marcia was kind enough to point me to a new website for Canadian Volcanoes; so I sent an inquiry into the alleged volcanic history of the Rossland area, and this was the reply I got:
hello Neil,
thanks for your message.
Rossland's most definitely not built in the crater or caldera of an ancient
volcano. It's geology is fairly old by active volcano standards, with the
youngest rocks being about 40 million years old. Those rocks are indeed
volcanic, and form a thick pile just west of Rossland (e.g. OK Mountain,
Roberts Mtn.) which runs sort of north-west. The pile is cut by faults and
deeply incised by erosion, so it's original extent and full relations --
which would have allowed me to say much more about it's volcanic history --
are largely hidden. The next oldest rocks go back to the 60 to 200 million
year period, and are dominantly granites. These are the sorts of rocks that
Rossland is built on. They are cut by "thrust" faults that formed in
response to tectonic forces ramming in from the west, pushing up the
Rockies. The granites represent magma chambers that might have been the
source zones for volcanoes in the 100 to 200 million year range but have
since been completed removed by erosion. Granites don't always act as root
zones for volcanoes, sometimes they intrude the crust and never produce
eruptions.
The ~40 million year old volcanic rocks are lava deposits called andesite
that are typical of tectonic subduction zone volcanoes. They were erupted
when the coastline was further east than now. As the western parts of BC
have been added to, the coast has stepped westward and so has the line of
active volcanoes. The volcanic rocks left behind, to the east of the coast,
got eroded and faulted with time.
There's no clear definition of an extinct volcano, but generally it's one
that shows no signs of activity now or historic time, it's last eruption was
hundreds of thousands or more years ago, and it is no longer in an area of
active tectonics that could produce magma to feed future eruptions. The
definition is problematic because some dormant volcanoes show few signs of
activity, erupt very infrequently, and some apparently "tectonically dead"
regions get very infrequent and poorly understood eruptions. In the case of
the Rossland volcanics, however, the great age and tectonic location, plus
the lack of volcanic-related hotsprings or seismic activity, indicate the
area's volcano is very much extinct.
best regards,
Mark Stasiuk
----------
From: Main Web Server[SMTP:webserve@nrn1.NRCan.gc.ca]
Sent: Saturday, June 02, 2001 6:17 PM
To: volcano@nrcan.gc.ca
Subject: Other: Sat. June 02, 2001
Neil Hodgins
neil_hodgins@hotmail.com
Hello;
I've had an interest in volcanoes for many years, and I'm glad to
finally see a site that\'s dedicated to the Canadian aspect of the field.
I had a question about an extinct (?) volcano that doesn't appear on your
map of BC. I've read that the town of Rossland, BC, is built in the
crater (caldera?) of an ancient volcano (the town's website,
http://www.rossland.com even makes mention of it). I've looked for more
information on this volcano, but have found no mention of it. Could you
tell me a little more about the geology and eruptive history of this site,
if it is indeed a volcano? Also, by what criteria is a volcano considered
to be extinct? Is it based solely on time between eruptions, or is there a
physical aspect such as erosion of the magma chamber?
Thanks,
Neil H.
PS. Very nice site you have here--well laid out and very informative. Info
on the T'seax eruption was especially interesting.
Topic 2 of 99 [Geo]: Vulcanism
Response 425 of 997: Marcia (MarciaH) * Tue, Jun 5, 2001 (20:55) * 117 lines
******************************************
Alaska Volcano Observatory Weekly Update,
6-01-2001
******************************************
From: avo-sci@usgs.gov
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, June 1, 2001 12:00 PM AST (2000 UTC)
MAKUSHIN VOLCANO (CAVW # 1101-31)
53o53'N 166o56'W
Elevation 5905 ft (1,800 m)
Since July of 2000 AVO has detected a slight increase in the number of
small earthquakes beneath Makushin Volcano located 25 km west of the city
of Unalaska/Dutch Harbor in the eastern Aleutian Islands. Hypocenters of
these earthquakes generally range between 0 and 8 km depth. These events
are too small to be felt by humans and are between magnitude 0.0 and 1.5.
The current activity at Makushin is not thought to be an immediate
precursor to eruptive activity. Similar fluctuations in earthquake
activity have been observed at a number of Aleutian volcanoes that did not
result in an eruption. The most recent eruption of Makushin occurred on
January 30, 1995 and consisted of a small explosion and ash plume that
reached heights of 10,000 ft (ASL). The level of concern color code for
Makushin Volcano remains at green.
OTHER ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
all at or near normal levels of background seismicity. AVO did not detect
ash plumes or significant elevated surface temperatures in the vicinity of
any volcano.
Abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of Alaska's volcanoes (907) 786-7478
CONTACT INFORMATION:
Tom Murray, Scientist-in-Charge, USGS
tlmurray@usgs.gov (907) 786-7497
John Eichelberger, Coordinating Scientist, UAF-GI
eich@giseis.alaska.edu (907) 474-5530
The Alaska Volcano Observatory is a cooperative program of the U.S.
Geological Survey, the University of Alaska Fairbanks Geophysical
Institute, and the Alaska Division of Geological and Geophysical Surveys.
*********************************
KVERT Information Release 35-01:
May 30, 2001 KDT
*********************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 35-01
Wednesday, May 30, 2001, 11:50 KDT (2250 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are in Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS ORANGE.
On the morning of May 24, a gas and steam plume was observed rising 1200 m
above the dome. The last satellite images at 16:27 KDT (04:27 UTC) and
18:11 KDT (05:11 UTC) on May 24, show a 4-6 pixel linear anomaly trailing
down the south-southwest flank of volcano. Maximum temperature is 38.9-50
degrees C. Further visual observations were absent until May 29 because of
poor weather.
On the morning of May 29, a gas and steam plume rose 1200 m above the new
dome. Gas and energetic steaming rose up to 300 m above the large area to
the right of the old dome. At 22:00 KDT (09:00 UTC) on May 29, a gas and
steam plume also rose 1200 m. On the morning of May 30, the volcano was
obscured by clouds.
Seismic activity has decreased, but remains above background levels.
Earthquakes of magnitude Ml=2 and many small earthquakes within the
volcano's edifice were recorded.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS.
Olga Chubarova
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006
RUSSIA
E-mail: ochubarova@emsd.iks.ru
tel. (41522) 59385
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
907-786-7497
Topic 2 of 99 [Geo]: Vulcanism
Response 426 of 997: Marcia (MarciaH) * Tue, Jun 5, 2001 (20:56) * 72 lines
******************
Colima, Mexico
******************
From: Juan Carlos Gavilanes
Volcan de Colima. New dome.
On March 17th 2001, Nick Varley and Juan Carlos Gavilanes made an ascent to
the Volcán de Colima crater. Circumnavigating the main crater, they recorded
the tracks and marked several waypoints simultaneously with 3 GPS navigation
receivers. Subsequent processing of the data allowed them to map the current
outer crater, which has a maximum diameter of 261 m and a minimum of 230 m.
The maximum depth was 40 m and the minimum was 15 m, giving an estimated
volume of approximately 1,400,000 m3. The same day they observed a new
crater located inside the northern sector of the outer crater, assumed to be
formed by the Feb 22th, 2001 explosion. The diameter of the inner crater was
estimated to be 127 m, its depth 15 m, and its volume 190,000 m3. This makes
it the biggest crater of Volcán de Colima since the early 1960's. In the NE
sector of the inner crater an inflated surface affected by fractures was
observed, which was interpreted by Varley and Gavilanes as a result of an
intrusive episode initiated sometime after the Feb 22 explosion.
On May 26th 2001, another ascent was made to the crater, discovering a new
lava dome. Its estimated dimensions were a diameter of 115 m at its base and
57 m at the top. Its height was estimated to be 30 m, giving a volume of
150,000 m3. Assuming that the extrusion started on May 8th, 2001, the
resulting growth rate would be 0.096 m3 s-1 (until May 26th 2001= 19 days).
During the 3 hours of work performed in the crater region (including gas
sampling), only a small rockfall was heard. From observations the new dome
is not composed by large dark-coloured blocks (as observed for the effusive
events that occurred during the last 40 years), but mainly by blocks of a
smaller size and light gray colour. In comparision to the previous crater
ascent, new and stronger fumarolic zones surrounding the new dome were
observed, mainly to its N, NE, and E. This is the first evidence of effusive
activity since the Nov 1998-Feb 1999 effusive episode.
Juan Carlos Gavilanes and Nick Varley. UNIVERSIDAD DE COLIMA.
*********************
Popocatepetl, Mexico
*********************
From: Dan Shackelford
Increased activity at Popocatepetl
Increased activity at Popocatepetl with a moderate explosive event at 2136
on 31 May sending glowing tephra onto the NE flank for up to 2-3km from
crater. Similar but smaller eruption at 0804 on 1 June. Five hours of
harmonic tremor followed the 31 May event.
From "Reportes Anteriores" (June 1) link on:
http://www.cenapred.unam.mx/cgi-bin/popo/mvolcan.cgi
Photo of eruption on 31 May at:
http://www.cenapred.unam.mx/popo/2001/may/p0601011.jpg
JUNE 1 11:00 h (16:00 h GMT):
In the last 24 hours, the Popocatepetl activity has shown an increase.
There were 4 small exhalations of low intensity of gas, steam and some
times carrying small amounts of ash. Yesterdeay at 21:36 there was an
explosion of moderate intensity. The event lasted one minute in its intense
phase. Incandescent material was sent on the North-east flank at distances
between 2 and 3 km from the crater (see image). It is possible that there
was a small ash plume, but it could not be confirmed. After a minute and a
half, episodes of harmonic tremor started. Their amplitude was small to
regular and they lasted about 5 hours. Today at 08:04, there was another
explosion, similar to the one from yesterday, but much smaller in size.
At the moment of this report, the summit of the volcano is covered by snow
and we can see a steam plume to the South-west.
Topic 2 of 99 [Geo]: Vulcanism
Response 427 of 997: Marcia (MarciaH) * Thu, Jun 7, 2001 (23:18) * 22 lines
By Rob on http://clubs.yahoo.com/clubs/worldvolcanism
On June 6 1912 on an island in the Aleutians the Alaskan volcano Katmai
began erupting through its vent called Novarupta. Novarupta is part of
a caldera volcano and has a dome of rhyolitic(?) lava plugging the
vent. Not much is known about the actual course of events because the
eruption was so far from civilisation but it is generally recognised to be
the largest eruption of the 20th
Century. As far as size goes nothing between 1900-1999 came anywhere
near the 32km3 of material blown clear across the northern Pacific
covering fishing boats, sea and land alike with a thick layer of pyroclasts.
On land the depth of the huge deposits ranges anywhere between 2cm and
200m thick with valley forming impromptu geothermal wonderlands (Valley
of 10,000 smokes).
Certainly Pinatubo in 1991 matched it for raw power and provided a
spectacle not seen before by Western people but this little volcano in
Alaska showed why the Aleutians geology makes the place such a dynamic area
to live in. Because of the position relatively close to the North Pole
it is doubtful that the volcano had any real affect on the climate of
the world except the northern polar regions.
Topic 2 of 99 [Geo]: Vulcanism
Response 428 of 997: Marcia (MarciaH) * Thu, Jun 7, 2001 (23:19) * 55 lines
Also by Rob on http://clubs.yahoo.com/clubs/worldvolcanism
In 1945 Mount Ruapehu erupted from it's crater lake emptying the
contents of the lake over the summit and down the Whangaehu river. When the
lake emptied the volcano built an andesitic lava dome in it's place. It
did not last long and within months had been blown to pieces showering
the central North Island with ash. However bad the ash was something
many times more dangerous and destructive was building. As the eruption
ceased an ash and debris dam formed above the Whangaehu outlet (an ice
tunnel through weak material)plugging the outlet).
On December 24 1953New Zealand learnt the definition of Whangaehu the
hard way. The rivers name is translated as "weeping waters" a name that
would soon become frighteningly appropriate. About 7.30PM water began
seeping through the sodden dam and quickly began carving out a gully
through which lake water began to pour. Downstream the Christmas rail
express with 285 passengers on board was merrily making it's way from
Wellington to Auckland for the holiday. It reached Waiouru and turned
westward. By now a lahar of mud consisting of water soaked-ash, boulders and
river sediment was crunching downhill from the lake at speed with a
peak flow of 900 cubic metres per second. It reached Tangiwai at 9PM and
clean bowled the rail bridge a few hundred metres away. A man named
Ellis was
driving home when he noticed a vast volume of water pouring over the
road bridge just down stream from the rail bridge, and realised there was
no way across after grabbing his torch to look. Then to his utter
horror he heard a toot. The train with it's 285 passengers on board was
approaching. So he raced up the bank with his torch frantically signalling
the train which could not even begin slowing down in the little time it
had left. It sailed into the air and came down on the other side in the
river. He smashed a window in the sixth carriage which was still
teetering on the bridge and started hauling injured passengers out while the
uninjured scrambled out, then the carriage fell in the raging torrent.
He ordered everyone out the broken window and scrambled out himself. He
saved 49 people from certain death and earned a Queens bravery medal
for his efforts. But the toll the lahar took was unreal. 151 dead. So
when the 1995 eruption sequence began in similar fashion to 1945, there
was an air of "oh no, here we go again" among some. The phreato-magmatic
eruptions of steam, mud and ash were spectacular to watch on television
and lahars left the pristine white slopes looking like they had ribbons
of set chocolate sauce on them. Unfortunately the cycle is almost
complete..................
It is now 2001 and the Government has just rejected a plan to bulldoze
a channel through the ash dam that has accumulated once more in the
entrance to the ice tunnel. It wants a warning system to give 2 hours
warning of an impending lahar (expected within 18 months)pouring down the
Whangaehu river. Although both ideas are sound, the local Maori do not
want bulldozers or anything else for that matter on the volcano because
of spiritual values. And the government thinks that conservation is
more important than risk REMOVAL approach. So it opted for risk REDUCTION.
Whatever happens, there is no denying the lahar risk. There is no
denying that there is a risk to human life and property and there is no
denying it WILL COME.
They have 18 months by my guess.
Topic 2 of 99 [Geo]: Vulcanism
Response 429 of 997: Marcia (MarciaH) * Thu, Jun 7, 2001 (23:23) * 32 lines
The latest HazardWatch is now online: http://www.hazardwatch.co.nz
A new publication is now available for sale. QMAP Wellington.
This full colour, large format geological map illustrates the geology of the
greater Wellington area and northeastern Marlborough (southern North Island and
northeastern South Island, New Zealand) at a scale of 1:250 000.
http://www.gns.cri.nz/news/publications/index.html#Wellington
A new conference is announced. The ILP (International Lithosphere Programme) .We
now offer the earthquake geology community, including the students, the final
opportunity under the auspices of ILP II-5 to present current research and
review papers for oral and poster presentation reflecting the ILP project II-5
theme of establishing large earthquake recurrence in pre-historic time using
paleoseismological methods.
http://www.gns.cri.nz/news/conferences/kai/index.html
A new vacancy at GNS, for a Geonet Admin Coordinator.
http://www.gns.cri.nz/news/vacancies/index.html
A new vacancy at GNS, for a Geonet Systems Developer.
http://www.gns.cri.nz/news/vacancies/index.html
A new vacancy at GNS, for a Geonet Systems Administrator.
http://www.gns.cri.nz/news/vacancies/index.html
A new vacancy at GNS, for a Geonet Operations Technican.
http://www.gns.cri.nz/news/vacancies/index.html
A new vacancy at GNS, for a Geodesist/Geophysicist.
http://www.gns.cri.nz/news/vacancies/index.html
Topic 2 of 99 [Geo]: Vulcanism
Response 430 of 997: Marcia (MarciaH) * Fri, Jun 8, 2001 (13:32) * 5 lines
It occurred to me that posting Rob's writings from his club was patently unfair since does not encourage people to join him and read his great articles there.
I encourage anyone who is even slightly interested in Volcanology to visit his WorldVolcanology at http://clubs.yahoo.com/clubs/worldvolcanism
Rob also has an impressive array of photographs and I am about to put one in there, as well. Join us there. We are discussing disaster preparedness. How well are you prepared to come through your next disaster? Flood? Earthquake?
Volcanic erutpion? Is anyone interested in discussing this subject here? If so I will create a new topic just for that. It is important and I can add a bunch of suggestions to help you survive your next cataclysm. Thinking they won't happen is foolish. Expecting the government agencies to dig you out is foolish. They are no better off than you are!
Topic 2 of 99 [Geo]: Vulcanism
Response 431 of 997: Marcia (MarciaH) * Fri, Jun 8, 2001 (15:41) * 177 lines
USGS VOLCANO NEWS
Volcano Watch - June 7, 2001
Diving deeply into Kilauea's early history
Kilauea wasn't always like it is today. Two hundred thousand years and the
change from a seamount to an island can do a lot to a volcano. The trick is
to determine what those changes were.
You can't do it on land. No erosion has bitten deeply enough into Kilauea
to expose its pre-island days. You have to look in deep bore holes or on
the sea floor to see back to Kilauea's early history. Even then it isn't
easy.
Recently a breakthrough was made. For the first time, the deep sea floor
south of Kilauea and east of the submarine volcano, Lo`ihi, was explored
and sampled by submersibles. The dives, some manned and some with a
remotely operated vehicle, took place in 1998 and 1999, supported by the
Japan Marine Science and Technology Center (JAMSTEC). The sea-floor
observations and samples have been analyzed and interpreted in a startling
scientific paper recently published by Pete Lipman (former HVO staff
member), his USGS colleague Tom Sisson, and two Japanese scientists,
Tadahide Ui and Jiro Naka in the December issue of the research journal,
Geology.
The deepest dive went 5 km (3 miles) down to the old sea floor on which the
island is built. Most of the dives were along a steep scarp or underwater
pali 20-40 km (12-24 miles) offshore. The scarp faces away from the island
at depths between about 3 km and 4.5 km (1.8 and 2.7 miles). Before the
dives, the scarp was hypothesized to contain lava flows erupted from Mauna
Loa and Kilauea, perhaps carried away from the island by a large underwater
slump.
Not true! Every rock sampled from the scarp, and all views of the scarp,
show that it consists of sandstone and broken rocks, not lava flows!
Imagine a pali 1,500 m (5,000 feet) high in Hawai`i consisting only of sand
and broken rocks. Nothing like that exists above sea level anywhere in the
islands.
What's going on?
That's what Lipman and colleagues wondered. So, they determined the
chemical compositions of the sand and broken rocks and found many of them
to be unlike anything found above sea level on either Kilauea or Mauna Loa.
Many of the samples are exceptionally rich in sodium and potassium
(alkalies). One of the rocks is even so alkalic that it contains the
mineral mica. Some of the chemical compositions resemble those found on
Lo`ihi, but the range of compositions is much greater. The data provide
solid evidence that Kilauea started out by erupting diverse alkalic rocks.
They also found evidence for a range of eruption depths by looking at the
amount of sulfur in glassy samples. High amounts (more than 800 ppm)
indicate eruption underwater; low amounts mean that the sulfur boiled off
and suggest very shallow or on-land eruptions.
Putting all this together, Lipman and colleagues suggest that early Kilauea
was a large submarine volcano, at times growing to or above sea level. It
was made of alkalic lava flows and was subject to numerous slope failures,
such as landslides. The slides broke up the lava flows and, with marine
currents, carried the debris onto the flanks of the volcano and beyond.
Eventually the compositions changed to the more common basalt (tholeiite)
found today, and pillowed basalt flows encroached on, and covered, the
flanks of the early volcano. Such flows occur on a large bench between the
top of the scarp and the island. The old alkalic volcano can be inferred
today only from its eroded debris exposed in the scarp; nearer the island,
it is covered completely by the tholeiitic flows.
The early history of Kilauea starts to come into focus. For greater
clarity, though, it needs a lot more sampling, geophysical profiling, and
thinking. But the general picture is there, thanks to the JAMSTEC dives and
the work by Lipman and colleagues.
Eruption Update
Eruptive activity of Kilauea Volcano persisted at the Pu`u `O`o vent during
the past week. Lava moves away from the vent area toward the ocean in a
network of tubes and descends Pulama pali in two separate areas. The
eastern flow near the Royal Gardens subdivision continues to be active and
supplies the ocean entry east of Kupapa`u. Another flow travels down the
pali about 1.5 km (0.9 mi) to the west of the boundary of Hawai`i Volcanoes
National Park. Lava from this western flow is now ponding in the coastal
flats and not going into the ocean. The ocean entry observed west of
Kamokuna last week stopped during the weekend.
One earthquake was reported felt during the week ending on June 7. A
resident of Hawaiian Ocean View Estates subdivision felt an earthquake at
8:16 p.m. on June 1. The magnitude-3.8 earthquake was located 6 km (3.6
mi) northeast of Pahala at a depth of 10.95 km (6.6 mi).
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
ALASKA VOLCANO OBSERVATORY
weekly Update
Friday, June 8, 2001 11:00 AM ADT (1900 UTC)
ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
all at or near normal levels of background seismicity. AVO did not detect
ash plumes or significant elevated surface temperatures in the vicinity of
any volcano.
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
During the past week (June 1-7), seismic activity was above background
levels. One MI=2 earthquake, many small earthquakes within the volcano's
edifice, and episodes of weak spasmodic volcanic tremor were recorded. On
June 5, a gas and steam plume rose 450-1200 m and extended 3-5 km to the W.
On June 7, a gas and steam plume rose 150 m and extended 5 km to the W.
According to reports from the town of Klyuchi, at 16:30 KDT (0330 UTC) on
June 7, an ash-gas plume rose 600 m above the dome and extended to the W.
At 16:50 KDT (3:50 UTC) a short-lived explosion sent an ash-gas plume 1500
m above the volcano accompanied by 3- and 2-minute-long, shallow seismic
events. On other days, clouds obscured the volcano. A thermal anomaly was
observed in satellite images at 18:09 KDT (05:09 UTC) on June 6, at 07:56
KDT (18:56 UTC) on June 6, and at 17:45 KDT (04:45 UTC) on June 7. The
first image has 2 saturated pixels (49C) in a background of 15-25C, the
second has 1 pixel at 49.3C in a background of near 4C, the third has three
pixels near saturation (44-45C) in a background of 15-25C, with a steam/ash
plume extending to the NW about 33 km.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels. On June 5-6, gas and steam
plumes rose 50-100 m above the volcano. On June 7, a gas and steam plume
rose 1500 m above the volcano and extended More than 10 km N. On other days, clouds
obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity was registered under the volcano. On June 6 and 7, gas and
steam plumes rose 100 m above the volcano and extended 10-15 km S and SW.
In the evening of June 7, a gas and steam plume rose 400 m and extended 10
km N. On other days, clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On June 5-6, gas and steam plumes rose 300-400 m above Mutnovsky Volcano.
On other days, clouds obscured the volcano. Gorely Volcano was obscured by
clouds the entire week. Seismic activity was at background levels. Since
June 3, episodes of weak spasmodic volcanic tremor were registered.
abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Topic 2 of 99 [Geo]: Vulcanism
Response 432 of 997: Marcia (MarciaH) * Fri, Jun 8, 2001 (16:02) * 12 lines
NEW ZEALAND volcano cams are back in action:
http://www.cybercorp.co.nz/ruapehu/
North Island, New Zealand
39.27S 175.58E
Summit Elevation 2796m
Local Time = GMT+12hrs (GMT+13hrs in NZ summer, effective October 1)
North Island's highest summit, 13 km SSW of Ngauruhoe, is marked by an acidic crater lake of highly variable
temperature. This has been the site of more historic eruptions than any other crater lake in the world.
Topic 2 of 99 [Geo]: Vulcanism
Response 433 of 997: Marcia (MarciaH) * Fri, Jun 8, 2001 (16:21) * 75 lines
********************************************
Satellite image, 4 June Sheveluch eruption
********************************************
From: Dan Shackelford
http://www.jpl.nasa.gov/images/earth/volcano/volcano_caption.html
*********************************
KVERT Information Release 37-01
June 7, 2001
*********************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 37-01
Thursday, June 7, 2001, 22:10 KDT (09:10 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
During the past week (June 1-7), seismic activity was above background
levels. One MI=2 earthquake, many small earthquakes within the volcano's
edifice, and episodes of weak spasmodic volcanic tremor were recorded. On
June 5, a gas and steam plume rose 450-1200 m and extended 3-5 km to the W.
On June 7, a gas and steam plume rose 150 m and extended 5 km to the W.
According to reports from the town of Klyuchi, at 16:30 KDT (0330 UTC) on
June 7, an ash-gas plume rose 600 m above the dome and extended to the W.
At 16:50 KDT (3:50 UTC) a short-lived explosion sent an ash-gas plume 1500
m above the volcano accompanied by 3- and 2-minute-long, shallow seismic
events. On other days, clouds obscured the volcano. A thermal anomaly was
observed in satellite images at 18:09 KDT (05:09 UTC) on June 6, at 07:56
KDT (18:56 UTC) on June 6, and at 17:45 KDT (04:45 UTC) on June 7. The
first image has 2 saturated pixels (49C) in a background of 15-25C, the
second has 1 pixel at 49.3C in a background of near 4C, the third has three
pixels near saturation (44-45C) in a background of 15-25C, with a steam/ash
plume extending to the NW about 33 km.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels. On June 5-6, gas and steam
plumes rose 50-100 m above the volcano. On June 7, a gas and steam plume
rose 1500 m above the volcano and extended ">"10 km N. On other days, clouds
obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity was registered under the volcano. On June 6 and 7, gas and
steam plumes rose 100 m above the volcano and extended 10-15 km S and SW.
In the evening of June 7, a gas and steam plume rose 400 m and extended 10
km N. On other days, clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On June 5-6, gas and steam plumes rose 300-400 m above Mutnovsky Volcano.
On other days, clouds obscured the volcano. Gorely Volcano was obscured by
clouds the entire week. Seismic activity was at background levels. Since
June 3, episodes of weak spasmodic volcanic tremor were registered.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Topic 2 of 99 [Geo]: Vulcanism
Response 434 of 997: Marcia (MarciaH) * Fri, Jun 8, 2001 (16:31) * 295 lines
GVP/USGS Weekly Volcanic Activity Report 30 May-5 June 2001
http://www.volcano.si.edu/gvp/usgs/
New Activity/Unrest: | Azuma, Japan | Colima, Mexico | Makushin, USA |
Ongoing Activity: | Etna, Italy | Kilauea, USA | Mayon, Philippines |
Popocatépetl, México | Shiveluch, Russia | Soufrière Hills, Montserrat |
Tungurahua, Ecuador
New Activity
AZUMA Honshu, Japan 37.73°N, 140.25°E; summit elev. 2,024 m
On 29 May the Fukushima Local Meteorological Observatory reported that
seismic activity increased slightly beneath Azuma during May. The
Coordinating Committee for the Prediction of Volcanic Eruptions’ seismic
network detected 51 small-magnitude volcanic earthquakes during 21 and 22
May and 39 on 21 May (the most recorded in one day since November 1998).
During March four low-frequency tremor events were recorded, while 40 were
detected in April.
Background. The Azuma volcanic group consists of a cluster of
stratovolcanoes, shield volcanoes, lava domes, and pyroclastic cones. The
complex was constructed in two E-W rows above a relatively high basement of
Tertiary sedimentary rocks and granodiorites W of Fukushima city. Volcanic
activity has migrated to the E, with the Higashi-Azuma volcano group being
the youngest. The symmetrical Azuma-Kofuji crater and a nearby fumarolic
area on the flank of Issaikyo volcano are popular tourist destinations. The
Azuma complex contains several crater lakes, including Goshiki-numa and
Oke-numa. Historical eruptions, mostly small phreatic explosions, have been
restricted to Issaikyo volcano at the northern end of the Higashi-yama group.
Source: Japan Times
http://www.japantimes.co.jp/cgi-bin/getarticle.pl5?nn20010530b6.htm
Azuma Reports
http://www.volcano.si.edu/gvp/volcano/region08/honshu/azuma/var.htm from
the monthly Bulletin of the Global Volcanism Network
COLIMA western México 19.514°N,103.62°W; summit elev. ~3,850 m
During an excursion to Colima on 17 March by personnel from the Universidad
de Colima a new crater was observed that was assumed to have been formed
during the 22 February 2001 eruption. The crater was ~190,000 m3 in volume,
making it the largest crater to form at Colima since the 1960s. On 26 May
scientists discovered that a new lava dome that was ~150,000 m3 in volume
had formed in the crater. They also noted that fumarolic activity was
stronger in May than in March and fumaroles were active around the new dome
mainly to the N, NE, and E. The new lava dome was the first evidence of
effusive volcanic activity since the November 1998-February 1999 effusive
episode.
Background. The Colima volcanic complex is the most prominent volcanic
center of the western Mexican Volcanic Belt. It consists of two
southward-younging volcanoes, Nevado de Colima (the 4,320 m high point of
the complex) on the N and the historically active Volcan de Colima at the
S. Volcan de Colima (also known as Volcan Fuego) is a youthful
stratovolcano constructed within a 5-km-wide caldera, breached to the S,
that has been the source of large debris avalanches. Major slope failures
have occurred repetitively from both the Nevado and Fuego cones, and have
produced a thick apron of debris-avalanche deposits on three sides of the
complex. Frequent historical eruptions have mostly originated from Colima's
summit crater. The current eruptive episode began in November 1998 and has
included summit lava dome growth to feed three SW-flank lava flows,
pyroclastic flows, and intermittent explosive activity.
Sources: Universidad de Colima via Volcano Listserv
http://www.volcano.si.edu/gvp/gvn/volclist/vla00141.htm
Colima Reports
http://www.volcano.si.edu/gvp/volcano/region14/mexico/colima/var.htm from
the monthly Bulletin of the Global Volcanism Network
MAKUSHIN Aleutian Islands, USA 53.90°N, 166.93°W; summit elev. 2,036 m
Since July 2000 AVO has detected a slight increase in the number of small
earthquakes beneath Makushin. The earthquakes generally ranged in depth
between 0 and 8 km and were too small to be felt by humans (M0-1.5). The
seismic activity was not considered to be an immediate precursor to
eruptive activity. Similar fluctuations in earthquake activity have been
observed at a number of Aleutian volcanoes that did not result in an
eruption. The Concern Color Code
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm remained at Green.
Background. The ice-covered, 2036-m-high Makushin volcano on northern
Unalaska Island is capped by a 2.5-km-wide caldera. The broad, domical
structure of Makushin contrasts with the steep-sided profiles of most other
Aleutian stratovolcanoes. Much of the volcano was formed during the, but
the caldera, Sugarloaf cone on the ENE flank, and a cluster of about a
dozen explosion pits and cinder cones at Point Kadin on the WNW flank, are
of Holocene age. A broad band of NE-SW-trending satellitic vents cuts
across the volcano, and a geothermal resource underlies the eastern
flank. Small-to-moderate explosive eruptions have been recorded at
Makushin since 1786.
Source: Alaska Volcano Observatory
http://www.avo.alaska.edu/avo4/updates/updates.htm
Makushin Reports
http://www.volcano.si.edu/gvp/volcano/region11/aleutian/makushin/var.htm
from the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
According to the Italy’s Volcanoes website, volcanic activity was at
similar levels as it has been during the previous few weeks. Lava continued
to travel from a vent on the NNE flank of the Southeast Crater cone, and
mild, discontinuous Strombolian activity continued at the Southeast
Crater’s summit vent. Scientists determined that the lava effusion rate was
approximately 5-10 cubic meters per second, which is high for Etna. On 31
May mountain guides reported that pressure waves, which were caused by
explosions, were observed approximately every 10 minutes and that volcanic
bombs were thrown ~100 m above the crater rim. Degassing was observed at
Southeast Crater and occurred to a lesser extent at Bocca Nuova crater, but
increased at Northeast Crater.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Source: Italy’s Volcanoes, http://www.geo.mtu.edu/~boris/ETNA_news.html
Etna Reports
http://www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm from
the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
During the beginning of the week lava flowed down Pulama pali and entered
the ocean at two areas. By 3 June there were few surface flows with most of
the lava traveling in lava tubes and entering the ocean sporadically. On 3
June a pause in volcanic activity may have begun at about 0900 with slow
deflation (~2.6 microradians) occurring at the tiltmeter closest to HVO.
The inflation ended around 2400 and on 4 June at 0125 rapid inflation (~2.7
microradians) began, most occurred in about 55 minutes. On 3 June at 1015
slow deflation (0.9 microradians) began at Pu`u `O`o and ended at about
2200. Slow inflation occurred at least until 4 June. Background volcanic
tremor at Kilauea`s summit gradually increased on 3 June starting at
mid-morning, after the deflation had begun. There was no significant change
in the tremor at Pu`u `O`o.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http://www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
During the week a large amount of high-frequency short-duration harmonic
tremor occurred at Mayon. The tremor was associated with the intermittent
descent of small lava avalanches and incandescent volcanic material down
the Bonga Gully on the SE flank of the volcano. Moderate amounts of steam
were observed rising from the summit crater where incandescence was
occasionally observed. SO2 emission (up to 2,900 metric tons/day) was above
the baseline value of 500 tons/day. Alert Level 3 remained in effect,
prohibiting entry within the 6-km-radius permanent danger zone. PHIVOLCS
warned that residents around the volcano, especially those staying in areas
facing the Bonga Gully and the SE sector, should be vigilant and prepared
to evacuate at any time.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Source: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm, Associated Press
http://news.24.com/News24/World/Australasia/0,1113,2-10-36_1032428,00.html
Mayon Reports
http://www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from
the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC 5 hours)
CENAPRED reported that on 31 May at 2136 a moderate-sized eruption began
with the most intense phase lasting ~1 minute. Incandescent material
traveled 2-3 km down the NE flank of the volcano. According to the Mexico
City MWO a steam-and-ash cloud was observed rising up to 7.6 km a.s.l. and
drifting to the W. A smaller eruption occurred on 1 June at 0804 that sent
a steam-and-ash cloud up to 7 km a.s.l.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de
Desastreshttp://www.cenapred.unam.mx/boletines.html, Washington VAAC
http://www.ssd.noaa.gov/VAAC/messages.html
Popocatépetl Reports
http://www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
Volcanic activity decreased following the 22 May eruption, therefore, on 30
May the Concern Color Code
was further
reduced from Orange to Yellow. During the week several small eruptions
produced gas-and-steam plumes that rose up to 1.2 km above the old lava
dome. Seismic activity decreased in comparison to the previous week, but
remained above background levels.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
MVO reported that during 25 May-1 June volcanic activity remained at high
levels. There was a significant increase in long-period earthquakes,
although most were small. MVO personnel observed an area of new growth in
the S sector of the lava dome. Sulfur dioxide flux varied, but was
generally lower than the previous week. The daytime entry zone remained
closed.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvomrat.com/
Soufrière Hills
Reports
http://www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
Volcanic activity increased at Tungurahua. A large number of long-period
earthquakes accompanied several small eruptions and near-continuous
gas-and-ash emission. The IG reported that an eruption on 31 May at 2120
produced an ash cloud that rose up to ~7.9 km a.s.l. and drifted to the W.
Incandescent blocks were ejected during the eruption, and an acoustic wave
that sounded like a cannon shot was heard several km away from the volcano.
Eruptions also occurred on 29 May at 2012 that sent ash to a height of ~8.2
km a.s.l., on 30 May at 1211 (ash plume to an unknown height), and on 2
June at 1709 with an ash plume to ~7.9 km. Incandescent material was
visible in the crater, and IG warned that heavy rain could remobilize ash
and generate lahars.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Source: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http://www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 435 of 997: Marcia (MarciaH) * Sat, Jun 9, 2001 (17:37) * 10 lines
I wonder if this will work... This is Kilauea's fume cloud, a picture I took
on my birthday. It has a rather nasty bromine brown color to it especially at
sunset (as this was) and is quite voluminous. This is the cloud stream that
goes more than 200 miles to Honolulu and makes their heads ache and skies hazy.
In fact, if you see the movie "Pearl Harbor" You can see it as a brownish
smog-looking layer on the distant horizon shots. That's from Kilauea!!!
Topic 2 of 99 [Geo]: Vulcanism
Response 436 of 997: Marcia (MarciaH) * Sat, Jun 9, 2001 (17:38) * 1 lines
Thanks for enabling, Rob! It works. I cannot yet FTP to the hard drive at Spring yet, and I did want to put this picture on Geo. Hugs and all sorts of good things!
Topic 2 of 99 [Geo]: Vulcanism
Response 437 of 997: Marcia (MarciaH) * Sat, Jun 9, 2001 (17:45) * 4 lines
You have to drive though that cloud to get to where we were and back home again.
No matter how well you close up the car and vents, you can taste that for ages afterward and when you lick your lips later, it tastes just like a reagent bottle. Actually, if it were not choking, it is a very exciting fragrance to me because it is of volcanic origin. Once you have smelled it, straight from the vent, you never forget. I am smiling just thinking of it. We did cough impressivly for a while, as did the entire group waiting to go see the activity.
There is now an "Hawaiian Breeze" scented room fragrance being advertized on the telly. Each time I see it I wonder if it is fumarole or floral.
Topic 2 of 99 [Geo]: Vulcanism
Response 438 of 997: Marcia (MarciaH) * Sat, Jun 9, 2001 (19:46) * 40 lines
So much for that.. it does not work either. I guess the new server better allow my ftp again before I can post images.
Thanks for this, Rob
Plan to control Ruapehu landslide dropped
08 JUNE 2001
By TRACY WATKINS
Conservation authorities have dropped a plan for a trench on Mt Ruapehu to prevent a massive mudslide
expected as early as next year.
They say Maori opposition was part of the reason.
Police and other emergency response groups have been meeting for months over plans to close the Desert Road and rail
bridges when the lahar comes, after reports showed the danger was imminent.
It had been suggested a trench be built at the overflow point of the crater lake on Ruapehu to prevent a lahar, but the
proposal has been dropped.
The Government has opted instead for an acoustic early warning system, which will give at least 45 minutes' alert of the
lahar reaching the Desert Road and two hours' warning for Tangiwai.
National MP and former conservation minister Nick Smith said yesterday that the Government had decided against the
trench because of opposition from Maori and environmental groups. He feared a disaster similar to the 1953 mudslide
that wiped out a rail bridge at Tangiwai, killing 151 people.
"(Conservation Minister Sandra Lee) is allowing political correctness over Maori spiritual values on Mt Ruapehu and
environmental sensitivities to prevent minor earthworks that are necessary for public safety."
Trampers would be at risk and there would be millions of dollars of damage done to the highway, railway and national
electricity grid, he said.
Ms Lee dismissed Mr Smith's claims as "recklessly alarmist".
"Once the (early warning) system is installed, there will be no chance of a repeat of the situation that led to the 1953
Tangiwai rail disaster where the lahar was unexpected as no warning system was in place."
Conservation Department spokesman Harry Keys confirmed that the lahar could come as early as summer next year.
more... http://www.stuff.co.nz/inl/index/0,1008,822145a11,FF.html
Topic 2 of 99 [Geo]: Vulcanism
Response 439 of 997: Marcia (MarciaH) * Sat, Jun 9, 2001 (20:20) * 3 lines
Rob's excellent series on Mt Pinatubo began today. I will make you go there to read it if you are interested. There is also a most valuable discussion on disaster preparedness that I would think all should be interested in. I would start such a topic here but I write on his club, so in the interest of fairness, please join us there as well as here. No sense duplicating such vlauable information unless it is to inform as many people as possible.
http://clubs.yahoo.com/clubs/worldvolcanism/bbsfrp?action=r&tid=worldvolcanism&sid=1600083236&mid=220
Topic 2 of 99 [Geo]: Vulcanism
Response 440 of 997: Marcia (MarciaH) * Sat, Jun 9, 2001 (20:24) * 3 lines
http://clubs.yahoo.com/clubs/worldvolcanism
Do youself a favor and join if you have something pertinent to add. We tolerate no off-topic discussions there, so leave that here. Rob is excellent. He runs a tight ship and I am his right hand person (not man, actually!)
Topic 2 of 99 [Geo]: Vulcanism
Response 441 of 997: Marcia (MarciaH) * Sat, Jun 9, 2001 (20:35) * 12 lines
Submarine eruption: http://www.nmnh.si.edu/gvp/gvn/world/gvn00047.htm
Subject: Explosive swarm near Supply Reef
From: "Rick Wunderman"
Date: Fri, 08 Jun 2001 14:43:26 -0400
A short explosive episode of submarine volcanism was recorded 24 april
2001 by our seismic station PMO on Rangiroa atoll, Tuamotu Archipelago. this episode began at 11:10 UTC, and ended at 19:00 UTC, with more than 40 explosive T waves at a fairly uniform rate. The wave form was
similar to those of december 1989, and suggested an explosive source in
the Marianna Islands. We have identified these explosive events on some other IRIS stations and Freesia stations, and computed a well constrained location at 20.34N, 145.02E, with an error of 15 km, near Supply Reef.
Topic 2 of 99 [Geo]: Vulcanism
Response 442 of 997: Rob Glennie (AotearoaKiwi) * Sun, Jun 10, 2001 (05:11) * 5 lines
Hi
It is recommended that you join, as this club is growing and has a resident seismologist, several geology students, a research writer/amateur volcanologist/civil defence member, and a geologist. At least two people have survived damaging earthquakes and the aim of the club to inform/prepare/educate people about volcanoes. The same thing can be said of World Seismicity for earthquakes.
Rob
Topic 2 of 99 [Geo]: Vulcanism
Response 443 of 997: Marcia (MarciaH) * Sun, Jun 10, 2001 (16:40) * 0 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 444 of 997: Marcia (MarciaH) * Sun, Jun 10, 2001 (16:44) * 7 lines
Indeed, Rob! I have created the disaster topic here, not to borrow from yours, but to amplify and extend its range,
perhaps. The more people we edify the fewer we have to extract from the ruins. Ideas tend to increase their efficiency
when exchanged with fellow thinkers. Join
http://clubs.yahoo.com/clubs/worldvolcanism
http://clubs.yahoo.com/clubs/worldseismicity
Topic 2 of 99 [Geo]: Vulcanism
Response 445 of 997: Marcia (MarciaH) * Mon, Jun 11, 2001 (16:50) * 3 lines
Great NASA images from waaaaaay up there of this eruption
http://www.jpl.nasa.gov/releases/2001/volcano0607.html
Topic 2 of 99 [Geo]: Vulcanism
Response 446 of 997: Marcia (MarciaH) * Wed, Jun 13, 2001 (13:12) * 38 lines
********************************
Piton de la Fournaise, Reunion
********************************
From: Thomas Staudacher
Piton de la Fournaise June 11, 2001
After continuous extensometer and inclinometer variations since begin of
April and increased seismic activity since end of Mai, a short seismic
crisis started at Piton de la Fournaise volcano on 11 June 2001 at 13h27
local time. During this crisis we recorded 126 seismic events.
At 13h50 a new eruption started on the ESE flank of Piton de la Fournaise,
as suggested by the observed extensometer variations, with several fissures
en echelon. Upper fissures started at about 2500 altitude on the south
flank, 200 m below the Dolomieu summit caldera. Final ones were located
between 2000 and 1800 m altitude on the east flank of PDF at the southern
base of crater « Signal de l'Enclos » and north of the « Ducrot crater ».
Several lava flows went down into the Grand Brûlé but their progression is
very slow. At 17h the front of the lava flow was still located at an
altitude of 1450 m.
In the morning of June 12, only the lower fissure at 1800 m altitude was
still active on about 200 m length, with several lava fountains of 20 to 30
m high. The lava flow followed the northern border of the March 27 eruption
and reached about 400 m altitude in the « Grand Brûlé ». Eruption still
goes on.
The last eruption on Piton de la Fournaise occurred on 27 March 2001, and
the different fissures of the present eruption are located in the same area.
Thomas Staudacher
Georges Boudon
Observatoire du Piton de la Fournaise
Institut de Physique du Globe de Paris
Topic 2 of 99 [Geo]: Vulcanism
Response 447 of 997: Marcia (MarciaH) * Thu, Jun 14, 2001 (23:51) * 15 lines
*********************************
Satellite images of Lopevi ash plume
*********************************
from: Brad Scott [B.Scott@gns.cri.nz]
LOPEVI Central Islands, Vanuatu 16.507°S, 168.346°E; summit elev. 1,413 m;
All times are local (= UTC + 11 hours)
Further to the recent posting on Lopevi, and contra to the reports from the
Darwin VAAC, satellite images of the ash plume were available shortly after the
eruption started on Friday from the NOAA site, see Vanuatu at
http://www.osei.noaa.gov/Events/Volcano/
Topic 2 of 99 [Geo]: Vulcanism
Response 448 of 997: Marcia (MarciaH) * Fri, Jun 15, 2001 (16:07) * 11 lines
Keeping the pulse of New Zealand's volcanoes http://www.gns.cri.nz/earthact/volcanoes/index.html
Current alert status of NZ's volcanoes
The two most recently active volcanoes in New Zealand are Mount Ruapehu and White Island.
The alert level for,
White Island is currently: Alert level 1
Mt Ruapehu is currently: Alert level 1
All other volcanoes are at: Alert level 0
Topic 2 of 99 [Geo]: Vulcanism
Response 449 of 997: Marcia (MarciaH) * Fri, Jun 15, 2001 (20:34) * 20 lines
***************************************
Update on Satellite Images of Lopevi Ash Plume
***************************************
From: Andrew Tupper [andrewt@bom.gov.au]
Please note an error was made in the weekly report. Gari has already kindly
corrected the web version at
http://www.volcano.si.edu/gvp/usgs/#lopevi .
A loop with GMS-5 visible, IR, and enhanced IR images is at:
http://www.bom.gov.au/info/vaac/images.shtml
Also note that Wellington VAAC continues to issue advisories on this event,
messages are on the web at
http://www.bom.gov.au/products/Volc_ash_latest.shtml or
http://www.ssd.noaa.gov/VAAC/OTH/NZ/messages.html
Topic 2 of 99 [Geo]: Vulcanism
Response 450 of 997: Marcia (MarciaH) * Fri, Jun 15, 2001 (20:45) * 47 lines
******************************
MVO weekly report, 15 June 2001
******************************
From: Gill Norton [Gill@mvo.ms]
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 8 June 2001 to midday, 15 June 2001
Activity at Soufrière Hills Volcano increased over the past week. The
seismograph network recorded 373 rockfall signals, 169 long periods, 35
long period rockfalls, 71 hybrids and no volcanotectonic earthquakes.
The number of rockfalls has increased since last week, as have the
number of both hybrid and long period earthquakes. In particular, there
was an increase in all types of activity from 12 June onwards.
Some views of the dome were possible earlier in the week, although
visibility was not great. There had been substantial new growth in the
southern sector, and it appeared that the summit of the new lobe over
Galway's was now the highest point on the dome. The dome was active over
a wide area from the southern side of Chances Peak to the southern side
of Tar River valley. Although there have been no large pyroclastic
flows, there has been a substantial accumulation of new dome material in
the upper reaches of the White River.
Sulphur dioxide fluxes increased markedly this week, with average daily
fluxes of 770 tonnes per day on 11 June and 1410 tonnes per day on 14
June. The latter value is the highest flux measured since early March
this year.
The daytime entry zone has been open for limited periods this week,
although the activity could increase again quite suddenly, with a
dangerous situation developing very quickly. Ash masks should be worn in
ashy conditions. In the event of heavy rain, the Belham Valley should be
avoided during and after the rainfall due to the possibility of mudflow
activity.
Residents of Montserrat and visitors to the island are advised to tune
into ZJB Radio for up-to-date information on the volcano. Access to
Plymouth, Bramble airport and beyond is prohibited. There is a maritime
exclusion zone around the southern part of the island that extends two
miles beyond the coastline from Trant's Bay in the east to Garibaldi
Hill on the west coast.
12 noon, Friday, 15 June 2001
Topic 2 of 99 [Geo]: Vulcanism
Response 451 of 997: Marcia (MarciaH) * Fri, Jun 15, 2001 (20:46) * 48 lines
********************************
AVO Weekly Update: June 15, 2001
********************************
From: avo-sci@usgs.gov
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, June 15, 2001 09:00 AM ADT (1700 UTC)
ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
all at or near normal levels of background seismicity. AVO did not detect
ash plumes or significant elevated surface temperatures in the vicinity of
any volcano.
Abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of Alaska's volcanoes (907) 786-7478
CONTACT INFORMATION:
Tom Murray, Scientist-in-Charge, USGS
tlmurray@usgs.gov (907) 786-7497
John Eichelberger, Coordinating Scientist
eich@giseis.alaska.edu (907) 474-5530
The Alaska Volcano Observatory is a cooperative program of the U.S.
Geological Survey, the University of Alaska Fairbanks Geophysical
Institute, and the Alaska Division of Geological and Geophysical Surveys.
Topic 2 of 99 [Geo]: Vulcanism
Response 452 of 997: Marcia (MarciaH) * Fri, Jun 15, 2001 (20:58) * 79 lines
************************************
KVERT Information Release 38-01:
June 15, 2001 KDT
************************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 38-01
Thursday, June 15, 2001, 12:20 KDT (23:20 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
During the past week (June 8-14), seismic activity was above background
levels. Eleven MI>=2 earthquake, many small earthquakes within the
volcano's edifice, local seismic signals (explosions, avalanches,
collapses), and episodes of weak spasmodic volcanic tremor were recorded.
According to seismic data, at 3:35 on June 8 (14:35 UTC on June 07), a
possible ash-gas explosion to a height of 2000 m above the dome (4500 ASL)
occurred, a 3-minute-long shallow seismic event was registered. According
to reports from the town of Klyuchi, at 8:22 KDT on June 13 (19:22 UTC on
June 12) a short-lived explosion sent an ash-gas plume to a height of 1000
m above the dome (3500 ASL) accompanied by 5-minute-long series of shallow
seismic events. On June 8-14, gas and steam plumes rose 1000-2000 m above
the dome and extended >10-20 km E and SE on June 8-9,11-12. On June 10 and
14, plumes extended 5-10 km W.
A thermal anomaly was observed in satellite images at 07:34 KDT (05:09 UTC)
on June 8, at 07:10 KDT (18:10 UTC) and 17:37 (04:37) on June 9, at 18:16
KDT (03:16 UTC) on June 10. First image has 4 pixels (19-38 dg C) in a
background of 8 C dg, the second has 2 pixels at 23.4 dg C in a background
of near 6 dg C, the third anomaly near SW flank of the volcano has 3 pixels
at 47.9 dg C in a background near 19 dg C, the forth linear anomaly
trending due south down the SW flank of the volcano and has 3 pixel at 44.9
dg C in a background near 18 dg C. Low altitude steam plume was observed in
image at 17:23 KDT (04:23 UTC) on June 8. The plume extended approximately
40 km SE of the volcano. A plume was observed in image at 17:30 KDT (04:30
UTC) on June 12 and extended to 35 km SE of the volcano.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
During the most part of the week, seismic activity was at background
levels. Since June 9, weak spasmodic volcanic tremor began to be
registered. At 18:07 KDT on June 14, a 12-minute-long series of strong
(Ml>=2) and small shallow earthquakes was registered. On June 8 and 11, gas
and steam plumes rose 1000 m above the volcano and extended >10 km NW on
June 8. On June 9-10, gas and steam plumes rose 1500-2000 m above the
volcano and extended 3-10 km E, NNE and NNW. On June 12-14, gas and steam
plumes rose 150-200 m above the volcano and extended 3-5 km SE and SW. On
other days, clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
One small shallow earthquakes was registered under the volcano on June 8.
No seismicity was registered under the volcano during the rest of the week.
On June 8, a gas and steam plume rose 1500 m above the volcano and extended
E. On June 9, 11-12, and 14, gas and steam plumes rose 300-600 m and
extended 5-20 km N and S. On other days, clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
Clouds obscured the volcanoes the entire week. Seismic activity was at
background levels. Weak spasmodic volcanic tremor was registered.
Topic 2 of 99 [Geo]: Vulcanism
Response 453 of 997: Marcia (MarciaH) * Sat, Jun 16, 2001 (16:49) * 29 lines
Thanks Hardin http://clubs.yahoo.com/clubs/worldvolcanism
Vanuatu Volcano Spews Ash, Smoke in South Pacific
PORT VILA, Vanuatu (Reuters) - A volcano on the uninhabited Vanuatu
island of Lopevi has been spewing ash and smoke since last Friday and has
caused cracks in the tiny South Pacific island, local media reported on
Wednesday.
More at http://clubs.yahoo.com/clubs/worldvolcanism
Ash and smoke had destroyed crops and contaminated water supplies on
nearby Paama Island, which had been evacuated, said the Port Vila Press
magazine.
Vulcanologist Douglas Charley, who is monitoring the volcano, said the
activity had subsided since Friday, but it may take months for the
volcanic activity on Lopevi to end.
The archipelago is made up of 13 large islands and 70 islets and has a
number of active volcanoes. The volcano on Tanna Island in the south of
the chain is a major tourist attraction.
Vanuatu, in the south west Pacific, has a population around 180,000,
of which only about 15 percent live in urban areas. An Australian navy
ship visiting the Vanuatu capital Port Vila, 90 miles south of Lopevi,
sailed to the active volcano on Sunday and Monday to conduct an aerial
reconnaissance and land three vulcanologists on nearby Paama. The HMAS
Kanimbla landing ship also delivered 22,000 gallons of fresh water to
Paama.
An Australian defense spokesman said Kanimbla would remain in the area
and be available for further aid relief.
Topic 2 of 99 [Geo]: Vulcanism
Response 454 of 997: Marcia (MarciaH) * Sat, Jun 16, 2001 (19:12) * 70 lines
Hawaii’s volcanoes are fed by hot spot deep in the Earth
U.S. Geological Survey
Hawaiian Volcano Observatory.
The hot-spot theory is the well-known modern explanation for the origin of the Hawaiian island chain.
In it, the Pacific plate drifts northwestward over a relatively fixed hot spot. Magma generated by the heat then
penetrates the plate and rises to the surface, leaving a string of volcanoes. The active volcanoes Kilauea,
Mauna Loa and adjacent submarine Lo'ihi are the Hawaiian hot spot's latest children.
Confusion commonly surrounds the distinction between the site of the hot spot and the site where magma is
generated, judging from the questions we receive. Let's start with the source of heat, which has two basic
causes.
Primordial heat was created when the planet first coalesced from cosmic debris. Additional heat has been
created by the decay of radioactive elements in the earth. The earth is cooling as this second source of heat
slowly diminishes.
Many geophysicists believe that hot spots originate as perturbations in a zone between the earth's core and
overlying mantle.
This zone, which lies about 1,700 miles deep, might develop a small bump that protrudes slightly outward into
the mantle from the core. The bump transmits the intense heat of the core into adjacent mantle, which in turn
is surrounded by cooler mantle.
Although solid, the hotter mantle material will rise because of its greater heat.
Convection is the process by which heated material rises and cooler material sinks. We see convection every
day; for example, the currents that swirl in a pot of liquid on a stove, or the warm air that rises over the
surface of sun-heated lava.
Solid materials also convect, although at considerably slower rates -- perhaps only a few centimeters per year
in the case of the mantle. Within the earth, heated blobs of mobile yet solid mantle rise within a solid cooler
mantle. Though heat is being transferred by these rising blobs, no magma is created because nothing has
melted.
Individual blobs probably don't traverse the entire mantle. As each one stalls, its heat is transferred to
adjacent rock, provoking continued convection. It's a "Pony Express" in which the horses will traverse only
one part of the mantle yet the message, the heat, continues through.
Heated rocks remain solid at the great pressures deep in the mantle. Perhaps about 60 to 70 miles deep,
however, the pressure is sufficiently low that melting can take place. Beads of magma sweat from the rocks
and rise.
Our convection system now comprises liquid rising within a solid mesh. The beads coalesce to create a
braided stream that penetrates the crust of the Pacific plate.
This intricate column of magma is broad enough to fuel Kilauea, Mauna Loa and Lo'ihi. Ultimately the magma
accumulates in complex reservoirs lying two to three miles beneath each active volcano.
In summary, a hot spot originates at relatively great depth, the magma at relatively shallow depth. The hot
spot is merely an anomalous concentration of the heat that is constantly being transferred from the earth's
interior to its surface.
In our current thinking, a spot begins as a perturbation at the core-mantle boundary, deep within the earth. If
the perturbation is sufficiently large, it takes on a life of its own, feeding a thermal plume that may last at least
80 million years, as in the case of the Hawaiian-Emperor volcanic chain. Heat is transferred upward by
convecting solids.
Magma forms when relatively shallow, solid mantle is torched by this heat. Lava is magma after it reaches the
earth's surface.
This article was written by scientists at the U.S. Geological Survey's Hawaiian Volcano Observatory. Contact
the observatory at P.O. Box 51, Hawaii National Park, HI 96718; or call (808) 967-7328. "Volcano
Watch" runs every Saturday.
[UPDATE]
Pu'u 'O'o vent continually
producing lava
Eruptive activity of Kilauea Volcano persisted at the Pu'u 'O'o vent during the past week.
Lava moves away from the vent area toward the ocean in a network of tubes. Small breakouts occur from
the tube system above Pulama pali, but most of the lava descends the pali in two separate flows.
The small eastern flow, near the Royal Gardens subdivision, continues to be weakly active. A tube in the
western flow carries lava down Pulama pali and then turns southeastward across the coastal flat, eventually
feeding the active ocean entry a quarter- to half-mile northeast of Kupapau. A more westerly stream in the
western flow travels down the pali and breaks out from the tube system at several places between the pali
and the shoreline, 2-1/2 to three miles from the end of Chain of Craters Road. Lava from this part of the flow
is not entering the ocean.
Topic 2 of 99 [Geo]: Vulcanism
Response 455 of 997: Marcia (MarciaH) * Sun, Jun 17, 2001 (18:45) * 18 lines
Thanks Hardin http://clubs.yahoo.com/clubs/worldvolcanism
On June 15, 1991, Mt. Pinatubo blew its top in one of the most
violent volcanic events of the century. Residents of island
of Luzon in the Philippines continue to live with the effects
of this massive eruption that dumped tons of debris on the
volcano's flanks. During monsoon rains, this debris can be
turned into rivers, or lahars, of corrosive ash that strip the
land of vegetation and harden into concrete-like structures.
Images using data from NASA's airborne imaging radar
instrument AIRSAR show the volcano's western side where most
of these pyroclastic flows occurred and how the landscape has
changed between 1996 and 2000.
They are available at
http://www.jpl.nasa.gov/images/earth/volcano/
Topic 2 of 99 [Geo]: Vulcanism
Response 456 of 997: Marcia (MarciaH) * Fri, Jun 22, 2001 (15:17) * 82 lines
Kilauea Volcano Watch - June 21, 2001
Volcano Watch - June 21, 2001
Acid rain, opal, and vegetation contrasts-thanks to Halemaumau
Few landscape changes are as extreme as that between the windward and
leeward sides of Kilauea's caldera. Simply drive from the Visitor Center in
Hawai`i Volcanoes National Park to the Southwest Rift pullout along Crater
Rim Drive. In a road distance of 7 km (4 miles) and straight-line distance
of 5 km (3 miles), one goes from a lush tree fern (hapu`u)-`ohi`a forest to
a nearly barren surface. Why? The volcano, mainly.
Precipitation drops rapidly in that distance, from a yearly average
of about 280-300 cm (110-120 inches) on the windward side to about 150-180
cm (60-70 inches) at HVO and somewhat less at the Southwest Rift pullout.
Such a drop certainly has an effect on the degree of vegetation. Still,
plenty of rain falls, no matter what side of the caldera you're on.
You might guess that the difference in cover is due to different ages
of volcanic deposits. But, that's not right. Most of the lava flows on
either side of the caldera were erupted from the shield volcano that once
formed the summit of Kilauea before it collapsed to form the caldera. These
flows were erupted mainly during the 14th century. That's plenty of time
for thick vegetation to grow-witness the marvelous forest from the park
entrance to Kilauea Iki.
Thick deposits of several explosive eruptions between about A.D. 1500
and 1790 cover the lava flows on both sides of the caldera. This tends to
slow the return of vegetation. A deposit of volcanic ejecta has fewer
cracks than does the surface of a lava flow, which shrinks as it cools and
fractures thoroughly. Cracks are where vegetation often gets started-for
example, note the ferns and `ohi`a in cracks of the Mauna Ulu flows along
Chain of Craters Road. So, it often takes longer for vegetation to return
to a surface blanketed by ash than to one underlain by cracked pahoehoe and
`a`a.
An important factor affecting vegetation is the grain size of the
surface explosive deposits. Those on the windward side tend to be
fine-grained material that holds water and quickly weathers to release
nutrients favorable for plant growth. The surface deposits on the leeward
side are coarse, commonly gravel in size, don't hold water, and don't
weather nearly as fast. Other things being equal, the fine volcanic ash
would therefore be a more favorable substrate than the coarse gravel.
There's a more important distinction between the windward and leeward
sides, though. Acid rain. Thanks to Halemaumau and its surroundings, about
100 tons of sulfur dioxide are emitted into the air daily. Trade winds blow
this gas into the Ka`u Desert. When it rains, the water combines with the
sulfur dioxide to form dilute sulfuric acid. Acid rain results.
Several measurements of the acidity just below the ground surface
have been made downwind of Halemaumau, in the Sand Hill area. Many of the
measurements show a soil pH (a measure of how acid the soil is) of about
3.5. That's about like dilute vinegar. Few plants like such acid
conditions.
The acid rain has another effect. As water percolates into the
ground, it dissolves silicon dioxide from volcanic glass in the explosive
deposits. Chemically, silicon dioxide makes up about half of the deposits,
so there's a lot available. If the ground water then encounters air, such
as at the ground surface, it evaporates, leaving the silicon dioxide behind
as a form of the mineral, opal. This mineral is what forms the hard crust
(hardpan) on much of the ground surface southwest of the caldera.
Vegetation doesn't like hardpan.
Acid rain, opal crust, gravelly deposits, reduced precipitation-these
factors are mostly responsible for making the leeward side of Kilauea's
caldera more barren than its lush upwind side.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week. Lava moves away from the vent area toward
the ocean in a network of tubes and descends Pulama pali in two separate
areas. The coastal flats tube system has developed and matured to a stage
where breakouts with surface flows are now seldom seen. The decrease of
surface breakouts may also be attributed to a possible decline in the
volume of lava in the tube system. Lava continued to enter the ocean in
the area east of Kupapa`u throughout the week.
There were no earthquakes reported felt during the week ending on
June 21
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
Topic 2 of 99 [Geo]: Vulcanism
Response 457 of 997: Marcia (MarciaH) * Fri, Jun 22, 2001 (19:17) * 34 lines
******************************************************
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 15 June 2001 to midday, 22 June 2001
******************************************************
Activity at Soufrière Hills Volcano has remained at about the same level
over the past week. The seismograph network recorded 462 rockfall
signals, 77 long periods, 43 long period rockfalls, 11 hybrids and 1
volcanotectonic earthquake. The number of rockfalls has increased since
last week, although numbers of other types of seismic events have
generally decreased. Towards the end of the week, the number of
rockfalls also decreased slightly.
Views of the dome were limited during the week due to low cloud and ashy
conditions, but it was confirmed that the growth is still concentrated
in the southern sector of the dome above Galway's. Near-continuous
rockfall activity was occurring in the upper part of White River,
although most of the events were small.
Sulphur dioxide flux decreased slightly this week, with average daily
fluxes of 460 tonnes per day on 15 June and 630 tonnes per day on 21
June.
The daytime entry zone has been open for limited periods this week,
although the activity could increase again quite suddenly, with a
dangerous situation developing very quickly. Ash masks should be worn in
ashy conditions. In the event of heavy rain, the Belham Valley should be
avoided during and after the rainfall due to the possibility of mudflow
activity.
Residents of Montserrat and visitors to the island are advised to tune
into ZJB Radio for up-to-date information on the volcano. Access to
Plymouth, Bramble airport and beyond is prohibited. There is a maritime
exclusion zone around the southern part of the island that extends two
miles beyond the coastline from Trant's Bay in the east to Garibaldi
Hill on the west coast.
12 noon, Friday, 22 June 2001
Topic 2 of 99 [Geo]: Vulcanism
Response 458 of 997: Marcia (MarciaH) * Fri, Jun 22, 2001 (19:30) * 263 lines
****************************************
GVP/USGS Weekly Volcanic Activity Report
13-19 June 2001
****************************************
New Activity/Unrest | Lopevi, Vanatua | Piton de la Fournaise, Réunion
Island |
Ongoing Activity | Etna, Italy | Kilauea, USA | Mayon, Philippines |
Popocatépetl, México | Shiveluch, Russia | Soufrière Hills, Montserrat |
Tungurahua, Ecuador |
New Activity
LOPEVI Central Islands, Vanuatu 16.507°S, 168.346°E; summit elev. 1,413 m;
All times are local (= UTC + 11 hours)
Based on a pilot report, the Wellington VAAC issued an ash advisory stating
that at 0302 on 14 June a small eruption produced an ash cloud that rose up
to ~1.8 km a.s.l. The cloud expanded towards the N over the islands of
Paama and Ambrym.
Background. The small 7-km-wide conical island of Lopevi is one of Vanuatu's
most active volcanoes. A small summit crater containing a cinder cone is
breached to the NW and tops an older cone that is rimmed by the remnant of
a larger crater. The basaltic-to-andesitic volcano has been active during
historical time at both summit and flank vents, primarily on the NW and SE
sides, producing moderate explosive eruptions and lava flows that reached
the coast. Historical eruptions at the 1,413-m-high volcano date back to
the mid-19th century. The island was evacuated following eruptions in 1939
and 1960. The latter eruption, from a NW-flank fissure vent, produced a
pyroclastic flow that swept to the sea and a lava flow that formed a new
peninsula on the western coast.
Source Wellington VAAC, http//www.ssd.noaa.gov/VAAC/OTH/NZ/messages.html
http//www.ssd.noaa.gov/VAAC/OTH/NZ/messages.html
Lopevi Reports
http//www.volcano.si.edu/gvp/volcano/region05/vanuatu/lopevi/var.htm
http//www.volcano.si.edu/gvp/volcano/region05/vanuatu/lopevi/var.htm
from the monthly Bulletin of the Global Volcanism Network
PITON DE LA FOURNAISE Réunion Island, Indian Ocean 21.23°S, 55.71°E; summit
elev. 2,631 m
Tremor associated with an eruption that began on 11 June had weakened by 16
June. The same day a fissure located on the E flank at the S base of crater
Signal de l'Enclos at 1,800 m altitude was intensely active. In an area
near the active fissure a cone began to form and lava fountains rose up to
30 m above the surface.
Background. The massive Piton de la Fournaise shield volcano on the island
of Réunion is one of the world's most active volcanoes. Most historical
eruptions have originated from the summit and flanks of Dolomieu, a
400-m-high lava shield that has grown within the youngest of three large
calderas. This latter caldera is 8 km wide and is breached to below sea
level on the eastern side. More than 150 eruptions, most of which have
produced fluid basaltic lava flows within the caldera, have been documented
since the 17th century.
Sources Thomas Staudacher and Georges Boudon, Observatoire du Piton de la
Fournaise Institut de Physique du Globe de Paris,
http//volcano.ipgp.jussieu.fr8080/reunion/Eruptions.htm
http//volcano.ipgp.jussieu.fr8080/reunion/Eruptions.htm
Piton de la Fournaise Reports
http//www.volcano.si.edu/gvp/volcano/region03/indian_w/pdlf/var.htm
http//www.volcano.si.edu/gvp/volcano/region03/indian_w/pdlf/var.htm
from the Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
The Italy's Volcanoes website reported that on 13 June, after ~44 hours of
low activity, the fourth eruptive episode within in a week began at
Southeast Crater. The episode lasted longer and was more intense than the
previous three episodes. Lava flowed from a vent on the NNE flank of
Southeast Crater cone. During the most intense phase of the eruption lava
fountains rose 150-200 m above the NNE flank vent. Strombolian bursts
occurred so frequently that they eventually blended into one continuous
pulsating fountain that rose up to 400 m. Also bursts periodically sent
bombs up to 500 m above the crater rim. A small amount of ash was emitted
with many of the stronger bursts. On 15 June another eruptive episode
occurred with activity similar to the 13 June episode.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna's summit craters
began in 1995.
Source Italy's Volcanoes, http//www.geo.mtu.edu/~boris/ETNA_news.html
Etna Reports
http//www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm
http//www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm
from the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Small surface pahoehoe lava flows were visible on the W end of the flow
field. Lava entered the sea at the E Kupapa`u ocean entry. Generally, weak,
steady tremor and related long-period earthquakes continued beneath
Kilauea's caldera. On 18 June for several hours there was a slight increase
in long-period earthquakes near the caldera. Tremor remained weak to
moderate near Pu`u `O`o and seismicity was at normal levels elsewhere.
Tiltmeters in the summit area and along the east rift zone indicated no
significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world's most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey's Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source US Geological Survey Hawaiian Volcano Observatory
http//hvo.wr.usgs.gov/kilauea/update/
http//hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http//www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htmhttp//www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev. 2,462 m
A high level of high-frequency low-duration harmonic tremor was detected on
Mayon that was associated with near-continuous detachment of hot rock
fragments from the summit lava dome. In addition, moderate amounts of steam
emanated from the crater, crater glow was fair-to-bright, and SO2 emission
(average of ~2,700 metric tons per day) was well above the baseline value
of 500 metric tons per day. Alert Level 3 remained in effect, prohibiting
entry within the 6-km-radius permanent danger zone.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon's most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Source Philippine Institute of Volcanology and Seismology
http//www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
http//www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Mayon Reports
http//www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm
http//www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m
Volcanic activity at Popocatépetl remained at normal levels, with several
small exhalations of steam, gas, and small amounts of ash. The volcano
remained at Alert Level Yellow Phase III, with a restricted 12-km-radius area.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site) http//www.cenapred.unam.mx/boletines.html
http//www.cenapred.unam.mx/boletines.html
Source Centro Nacionale de Prevencion de
Desastreshttp//www.cenapred.unam.mx/boletines.html,
Popocatépetl Reports
http//www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html
http//www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html
from the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev. 3,283 m
During 8-14 June seismic activity was above background level at Shiveluch.
Many small earthquakes occurred within the volcano's edifice and local
seismic signals accompanied explosions, avalanches, and collapses. There
were several ash-and-gas eruptions, with the highest eruption cloud
reaching up to 2 km above the lava dome. A thermal anomaly was observed on
satellite imagery on 8,9, and 10 June. The level of Concern Color Code
http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
remained at Yellow.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm
http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm,
Shiveluch Reports
http//www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
http//www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev.
1,030 m; All times are local (= UTC 4 hours)
From 12 June to at least 15 June volcanic activity increased at Soufrière
Hills in comparison to the previous week. There was a larger number of
rockfalls, and hybrid and long-period earthquakes. Sulfur dioxide flux
markedly increased (770 metric tons on 11 June and 1410 metric tons on 14
June). New growth was substantial in the southern sector of the lava dome
and there was a large accumulation of new dome material SW of the dome in
the upper reaches of the White River. The daytime entry zone was open for
limited periods during the week. The Washington VAAC reported that at 0510
on 14 June a small ash cloud rose 3-4.5 km a.s.l. and drifted to the W and
that low-level ash was emitted throughout the week. In addition, moderate
rockfall activity produced ash to ~2 km a.s.l. and a hot spot was
occasionally visible on satellite imagery.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Sources Montserrat Volcano Observatory http//www.mvomrat.com/
http//www.mvomrat.com/, Washington
VAAC, http//www.ssd.noaa.gov/VAAC/messages.html
http//www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills
Reports
http//www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
http//www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m
Several small eruptions produced ash clouds that rose to a maximum height
of ~9.7 km. The IG reported that the number of long-period earthquakes and
the emission of gas and ash had increased since the end of April. They
warned that heavy rain could remobilize ash on the flanks of the volcano,
generating dangerous lahars.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador's capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources Instituto Geofísico, http//www.epn.edu.ec/~igeo/index.html
http//www.epn.edu.ec/~igeo/index.html,
Washington VAAC http//www.ssd.noaa.gov/VAAC/messages.html
http//www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http//www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
http//www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 459 of 997: Marcia (MarciaH) * Fri, Jun 22, 2001 (19:36) * 53 lines
*****************************************************
Kamchatkan Volcanic Activity
INFORMATION RELEASE 39-01
Thursday, June 22, 2001, 11:30 KDT (22:30 UTC)
*****************************************************
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
During the past week (June 15-21), seismic activity was above background
levels. On June 18-19, five MI>=2 earthquakes occurred. Many small
earthquakes within the volcano's edifice, local seismic signals
(explosions, avalanches, collapses), and episodes of weak spasmodic
volcanic tremor were recorded. According to seismic data, at 20:57 on June
18 (07:57 UTC), and at 04:31 on June 20 (15:31 UTC on June 19), possible
weak ash-gas explosions occurred, and 20-minute-long and 3-minute-long
shallow seismic events were registered. In the evening of June 15, a gas
and steam plume rose 800 m above the dome. At other times, clouds obscured
the volcano. A steam plume was observed in a satellite image at 16:51 KDT
(03:51 UTC) on June 18. The plume extended approximately 40 km N of the
volcano.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
During most of the week, seismic activity was at background levels. On June
20, four strong (MI>=2) shallow earthquakes were registered. Clouds
obscured the volcano the entire week.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity was registered under the volcano. Clouds obscured the
volcano the entire week.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
Clouds obscured the volcanoes the entire week. Seismic activity was at
background levels. Weak spasmodic volcanic tremor was registered.
Topic 2 of 99 [Geo]: Vulcanism
Response 460 of 997: Marcia (MarciaH) * Fri, Jun 22, 2001 (19:57) * 70 lines
Rob's eloquesnt tribute to David A. Johnston
http://clubs.yahoo.com/clubs/worldvolcanism
I thought given we recognized the Mount St Helens anniversary this
year, it would not do to go without recognising the efforts of the United
States Geological Survey in predicting the first eruption on the
continental 48 states for 63 years. Before we continue however now is a good
time to say thanks to all the geologists who risked life and limb to get
the data about the volcano, and in particular a man who gave everything
to his work and finally it cost him his life.
David Johnston - his fate is debatable. Some say the shock wave from
the blast killed him, others say the lateral blast vapourised him like it
did 25 others whose bodies were never seen again. What is certain is
his certainty that the volcano would blow, doubtlessly meant his warning
"the mountain is a powder keg", was taken seriously.
He was the only man with personal experience on a dangerous volcano.
Sure others had flown over one or climbed into the crater, but they had
not survived pyroclastic flows hurling lava bombs before them, as he had
in Alaska at Augustine during his research prior to Mount St Helens.
Because of this David could appreciate a stratovolcano's ability to
explode - something those that had spent their time in Hawaii studying lava
flows and fountains and who now found themselves facing, could not. He
could also appreciate the ability of pyroclastic flows to mushroom
outwards and was justfiably scared when the bulge became apparent to all
with eyes to see, knowing that the bulge represented an overload of gas
filled magma.
On May 17, 1980 - a day which seemed like any of the 56 preceding days
in the volcano crisis, Johnston was asked if he could stand in for
Glicken, while he saw of a German student. Johnston initially said no for
the reasons already listed but Don Swanson, who was responsible for them
persisted. Finally David relented, and Swanson said he would see that
Johnston was relieved in the afternoon of the following day. As the sun
set over Mount St Helens that night, the volcano was putting the
finishing touches to a grand plan that would shake Washington State to the
core.
The sun rose the following morning at 5.37AM with the mountain still
looking relatively drowsy. Johnston got up in the cool dawn sunshine and
promptly radioed the Vancouver observatory to report measurements that
he had been making. It was a brilliantly clear and calm day with no
hint whatsoever of the horror that would shortly explode across the
landscape with a violence that would leave the United States stunned.
At 8.28 Johnston was back on the radio to the Vancouver observatory, to
update the USGS on the measurements he was doing. Two minutes later
there was a earthquake - M5.1 less than a kilometre below the summit. On
the outside it appeared nothing had happened. Johnston could not see the
rocks sliding into the crater or the cracks opening on the summit.
Then in 30 mind-numbing, shock inspiring seconds his whole world
changed.
VANCOUVER!!! VANCOUVER!!! THIS IS IT!!! And the world never heard nor
saw David A. Johnston alive again.
A blast bigger and uglier than anything ever imagined in the minds of
anyone monitoring the volcano had just blown down 150 square miles of
pristine forest. At least a dozen people were already dead, incinerated
by the lateral blast, blown to pieces as Johnston probably was, or
simply vanished in the maelstrom. And all this time a huge Plinian column
punched through one segment after the other of the atmosphere. But David
Johnston would never have known any of this for he was the first
volcanologist in the twentieth century to die on a volcano in the United
States.
Rob
Topic 2 of 99 [Geo]: Vulcanism
Response 461 of 997: Marcia (MarciaH) * Sat, Jun 23, 2001 (22:20) * 23 lines
Mayon erutpts
Philippine Volcano Spews Lava, Big Blast Feared
Reuters
Jun 23 2001 10:21AM
LEGAZPI, Philippines (Reuters) - A Philippine volcano hurled out
fountains of lava Saturday in what could be a prelude to a major eruption,
forcing thousands of villagers to flee their homes, officials said.
There were no immediate reports of casualties, they said.
The Philippine Institute of Vulcanology and Seismology said "the
explosive discharge of lava" reached heights of at least 160 feet and sent
flaming rocks and gases tumbling down the slopes of the 8,000-foot
Mayon volcano.
The institute said it had raised the alert level around the volcano from
three to four, meaning "a hazardous, explosive eruption is possible within
hours to days."
More...
http://my.aol.com/news/news_story.psp?type=1&cat=0200&id=0106231022342821
Topic 2 of 99 [Geo]: Vulcanism
Response 462 of 997: Marcia (MarciaH) * Sun, Jun 24, 2001 (18:34) * 83 lines
Philippine Volcano Spews Truck-Sized Boulders
Reuters
Jun 24 2001 11:39AM
LEGAZPI, Philippines (Reuters) - Tens of thousands of villagers fled their
homes as the Philippines' Mayon volcano unleashed a series of
thunderous eruptions on Sunday.
Scientists said Mayon was spitting out flaming ash and boulders as big
as trucks.
There were no casualties directly as a result of the eruptions, but one
man trying to flee on a bicycle was knocked down and killed by a truck.
Witnesses said deafening booms rang out and giant cauliflower-shaped
clouds of dust, ash and smoke shot up to six miles into the sky,
darkening this provincial capital of 120,000 people as well as
surrounding towns.
The blasts prompted the Philippine Institute of Vulcanology and
Seismology (Phivolcs) to raise the alert level around the volcano to a
maximum five, meaning "a hazardous eruption is in progress."
Officials said about 23,000 villagers fled their homes as the series of
explosions, which began on Saturday night, intensified on Sunday and
shook villages as far as 12 km (eight miles) away.
"The rocks coming down are as big as trucks," vulcanologist Alex Baloloy
said just before the first big blast at noon.
A more powerful blast two hours later showered villages with ash --
so-called black rain -- and sent mothers scurrying out of their homes
clutching their babies in their arms.
"Leave, let us all leave," one mother cried as the mountain heaved and
the ground under her shook.
Residents of the capital Legazpi, 7.5 miles from Mayon's summit,
watched with fear and awe as the 8,000-foot-high mountain released its
fury.
RIVERS OF FIRE
"I heard what seemed like a huge thunder and I saw dark clouds ... then
more boom-boom sounds," local journalist Rhaydz Barcia said.
Moments later, fiery rocks and gas thundered down the volcano's slopes
at speeds estimated at 60 mph.
Phivolcs chief Raymundo Punongbayan said the "rivers of fire" bore
temperatures of 900 degrees Centigrade, hot enough to incinerate
anything in their path.
The eruption might last one or two weeks, he said.
Army trucks and police cars sped out of Legazpi to threatened villages in
a massive evacuation effort. Some villagers fled on carts driven by
carabaos (water buffaloes).
In the panic, one woman collapsed with a heart attack while a pregnant
mother prematurely gave birth, rescue officials said.
One villager fleeing on a bicycle was killed when a speeding van carrying
rescue teams struck him, officials said. Another truck full of evacuees fell
into a canal, injuring some of them.
In Daraga town, soldiers rushing to evacuate villagers ran into gunfire
from communist rebels, triggering a 10-minute gunbattle. No-one was
reported killed.
Priests tolled church bells and village chiefs sounded sirens to rouse
sleeping residents and order them to flee.
In Matanag village, reporters saw parents shaking with terror as they
hastily packed up their possessions while clusters of children, oblivious
of danger, watched fountains of lava shooting up from the crater.
"It's just like Christmas," some of the children chanted.
Mayon, located in Albay province, 205 miles southeast of Manila and one
of the Philippines' 22 active volcanoes, has a history of 45 violent
eruptions since its first recorded blast in 1616. The deadliest occurred in
1814 when it buried a town under mud and rocks and killed 1,200 people.
Topic 2 of 99 [Geo]: Vulcanism
Response 463 of 997: Marcia (MarciaH) * Mon, Jun 25, 2001 (19:02) * 106 lines
********************
Mayon, Philippines
********************
From: Dan Shackelford
At 0405 on 19 June 2001 a significant change in Mayon's activity began.
Accompanied by bright glow from the summit dome, a lava flow began to
extend down from the dome, accompanied by tremor. By early 20 June the
glowing lava flow was some 500m below the dome. This means that hotter and
gas-rich lava has now been intruded into Mayon and reached the surface. SO2
increased abruptly from 1700 metric tons/day to 6,000 tons/day with the
arrival of this new lava extrusion. Increased inflation of the edifice is
also occurring.
-----
Following up on the report of a change in character in Mayon's activity
several days ago as hotter, gas-rich lava had broached the surface, on 24
June a rather spectacular eruption developed, with an ash plume 15 km
a.s.l. and pyroclastic flows down the SE flank. This was preceded by
increasing explosive activity and warnings were issued before this event.
-----
Significant eruptions at Mayon from 1444 - 1541 on 24 June, with strong
explosions, multiple pyroclastic flows down SE flank, lava flowage down SE
flank, and moderate to heavy ashfalls to NE. This has been followed by
weaker ash emissions but lava flowage continues as of 25 June.
From:
http://www.phivolcs.dost.gov.ph/vmepd/mayon_bulletin.htm
http://www.phivolcs.dost.gov.ph/Volcanoes/Mayon/MayonIndex.html
http://www.cnn.com/2001/WORLD/asiapcf/southeast/06/24/phil.volcano/index.html
-------------------------
Mayon Volcano Bulletin
10:00 AM 20 June 2001
A significant change in the pace of unrest was indicated by appearance of
tremor at about 4:05 AM yesterday. The tremor meant that lava extrusion
hastened and formed a lava flow. A brief cloudbreak from 10:08 PM to 1:52
AM showed intense glow emitted by the dome and conspicuous incandescence
from the margins of a newly emplaced lava flow, which now extends to about
500 meters below the summit dome (about 1,800-1,900 meters elevation).
The tremor, which dominated the seismic records, meant that discrete
rockfall counts were fewer and that is why only 76 rockfall-related tremors
were registered although activity had actually increased through the
formation of a lava flow. The lava flow signifies that hotter, more fluid
and more voluminous lavas are being extruded. The newly extruded lavas
possibly contain more volcanic gases, as indicated by the sudden increase
of sulfur dioxide emissions from the average 1,700 tonnes per day (t/d)
last week to nearly 6,000 t/d yesterday. Other more subtle but notable
physical changes are also occurring. The volcanic edifice has slightly
inflated as shown by Electronic Distance Meter (EDM) measurements.
Tiltmeters at the Buang-Mayon Resthouse stations also report accelerating
ground deformation towards additional inflation or swelling of the volcano
edifice.
The appearance of a tongue of lava extending from the summit lava dome is
significant, for it signifies acceleration in the overall activity of the
volcano. The high gas content of newly extruded lavas also suggests that
more explosions can be expected. An explosion can either erupt voluminous,
gas-charged lava or cause a large chunk of dome material to detach from the
summit. In both cases, hazardous pyroclastic flows can be produced. At
this stage, Alert Level 3 (Hazardous Eruption Possible in Weeks) is in
effect but activity may accelerate to the point of going to Alert Level 5
(Hazardous Eruption In Progress) if sudden explosions produce
life-threatening volcanic flows. PHIVOLCS emphasizes that the 6-kilometer
radius Permanent Danger Zone (PDZ) should be off-limits at all times and
that residents fronting or staying beside gullies radiating from the
volcano should be alert for advisories requiring them to move out on first
notice. For the moment, PHIVOLCS is not yet recommending additional areas
to be evacuated, except those that are already listed within the PDZ.
PHIVOLCS
-------------------------
Mayon Volcano Bulletin
25 June 2001
6:30 A.M.
After declaring Alert Level 5 (Hazardous Eruption in Progress) at 1:00 P.M.
yesterday, major eruptions began at 2:44 P.M. The eruptions were
characterized by strong explosions, multiple pyroclastic flows around the
volcano and lavas that flowed into gullies on the southeast flanks. The
pyroclastic flows passed through the major river channels fronting Basud,
Buyuan, Mabinit/Bonga, Miisi, Anoling, Maninila, Nabonton and Buang, all
within the 6-kilometer radius Permanent Danger Zone (PDZ). The main
eruption cloud discharged from the crater rose to about 10 kilometers
altitude and moderate to heavy ash were dispersed mainly to the Northeast
in the vicinity of Malilipot by prevailing winds. Residents in Tabaco
farther Northeast also experienced light ashfalls.
Although lava flows and dilute ash clouds dominated subsequent activity
from 3:41 P.M. until activity waned early this morning, PHIVOLCS expects
similar explosive activity in the following days. The general public is
therefore reminded that Mayon is still at Alert Level 5 and that the
previously delineated danger zones should be strictly off-limits. These
areas are the 6-kilometer PDZ and the Extended Danger Zone (EDZ) to the
southeast facing Mabinit, Bonga, Matanag and Buyuan Gullies. These areas
are most susceptible to hazards by pyroclastic flows, volcanic blasts and
ground surges. In the event of large explosive eruptions, more areas may
be declared as danger zones. Because of the changing wind drifts, and ash
derived from pyroclastic deposits, areas just beyond the danger zones
should expect ashfall and prepare accordingly. Due to rain clouds that
persist over the volcano, PHIVOLCS also cautions the public to avoid
venturing near the river channels around Mayon because hot and
life-threatening debris flows may occur with little warning.
PHIVOLCS
Topic 2 of 99 [Geo]: Vulcanism
Response 464 of 997: Marcia (MarciaH) * Mon, Jun 25, 2001 (19:37) * 5 lines
For you viewing pleasure. Mt St Helens thanks to the remarkable frames take by Rosenquist and found on http://pubs.usgs.gov/publications/msh/catastrophic.html
My first attempt at doing this:
Topic 2 of 99 [Geo]: Vulcanism
Response 465 of 997: Neil Hodgins (ThinkingManNeil) * Tue, Jun 26, 2001 (06:26) * 1 lines
Wow! Very dynamic--certainly gives a better impression of the eruption than just still photos. Nice work, Marci!
Topic 2 of 99 [Geo]: Vulcanism
Response 466 of 997: Marcia (MarciaH) * Tue, Jun 26, 2001 (13:56) * 3 lines
Thanks, dear! I wish Ihad known earlier about this little utility I have on this computer. Anyone want me to make them for their pictures? I can make the slower or fasted depending if you want it to look like a video,as in this one, or as flipping slowly through an album, as Liam does with his.
It is so good to see you back again, Neil. *Big Get-well Hugs*
Topic 2 of 99 [Geo]: Vulcanism
Response 467 of 997: Marcia (MarciaH) * Wed, Jun 27, 2001 (20:25) * 16 lines
* Elastic lava blows its top: (26 Jun)
Some volcanoes explode in one violent outburst, but the
regular eruptions of an active 'Strombolian' volcano are
interrupted by 'chugging' - that is, frequent small
eruptions. Jonathan Lees of the University of North
Carolina, US, and colleagues believe that this
characteristic pattern is due to the viscoelastic
properties of lava, and they have developed a model that
accurately predicts the behaviour of these periodically
exploding volcanoes. Lees and colleagues based their
model on studies of Karymsky, a Strombolian-type volcano
in eastern Russia that has active periods that last about
12 years separated by similar periods of calm.
[ http://PhysicsWeb.org/article/news/5/6/14 ]
----------------------------------------------------------
Topic 2 of 99 [Geo]: Vulcanism
Response 468 of 997: Rob Glennie (AotearoaKiwi) * Thu, Jun 28, 2001 (06:37) * 7 lines
Hi
Marci, remember we talked a while ago somewhere about the Mount St Helens documentary "Anatomy of a volcano"?? Well, looking at the Rosenquist movie you created, I think the only thing missing is the cold chilling music that accompanies the clip on the documentary. My supreme moment in Geology to date was when Professor Cole showed that documentary. I did not watch the clip, I watched people's faces for reaction. I think all I got was stunned silence - it was brilliantly chilling.
Rob
Topic 2 of 99 [Geo]: Vulcanism
Response 469 of 997: Marcia (MarciaH) * Thu, Jun 28, 2001 (17:59) * 3 lines
If there had been a way to add the music (Did not find it as yet) I would have done so. I have never viewed that footage and music without the same effect on the audience you experienced. It adds to the chills I get when I do see it - remembering how powerful images and music can be when it is just right.
Which reminds me, did you watch the Mir Requiem I posted for you? That music will bring tears to your eyes if you are as moved as I think you will be.
Topic 2 of 99 [Geo]: Vulcanism
Response 470 of 997: Marcia (MarciaH) * Thu, Jun 28, 2001 (21:15) * 306 lines
GVP/USGS Weekly Volcanic Activity Report - 20-26 June 2001
http//www.volcano.si.edu/gvp/usgs/
New Activity/Unrest | Manam, Papua New Guinea | Mayon, Philippines |
Ongoing Activity | Etna, Italy | Kilauea, USA | Piton de la Fournaise,
Réunion Island | Popocatépetl, México | San Cristóbal, Nicaragua |
Shiveluch, Russia | Soufrière Hills, Montserrat | Tungurahua, Ecuador |
New Activity
MANAM offshore New Guinea, Papua New Guinea 4.10°S, 145.06°E; summit elev.
1,807 m
According to information from pilot reports, Rabaul Volcanological
Observatory (RVO), NOAA, and GMS imagery, the Darwin VAAC reported that on
25 June Manam produced multiple lava flows and an ash cloud that rose to a
maximum height of 4.5 km a.s.l. The ash cloud was not visible on satellite
imagery. RVO noted that occasional low-level ash emissions had been
observed since 20 June.
Background. The 10-km-wide island of Manam is of one of Papua New Guinea's
most active volcanoes. Four large radial valleys extend from the
unvegetated summit of the conical 1,807-m-high stratovolcano to its lower
flanks. These "avalanche valleys," regularly spaced 90 degrees apart,
channel lava flows and pyroclastic avalanches that have sometimes reached
the coast. Five satellitic centers are located near the island's shoreline.
Two summit craters are present; both are active, although most historical
eruptions have originated from the southern crater, concentrating eruptive
products during the past century into the SE avalanche valley. Frequent
historical eruptions have been recorded since 1616.
Source. Darwin VAAC http//www.bom.gov.au/info/vaac/advisories.shtml
Manam Reports
http//www.volcano.si.edu/gvp/volcano/region05/offshore/manam/var.htm from
the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m; All times are local (= UTC + 8 hours)
A large, pyroclastic-flow producing eruption began at Mayon on 24 June at
1245. The first signs of heightened volcanic activity occurred on 19 June
when tremor began that was associated with increased lava extrusion. SO2
emission increased to 6,000 metric tons on 19 June in comparison to an
average of 1,700 metric tons per day the previous week. In addition,
intense incandescence was observed at the dome and slight inflation was
detected. By 23 June lava was rapidly flowing SE along the Bonga Gully
towards the town of Mabinit, reaching 3.4 km from the volcano’s summit. The
same day at 1909 lava fountains rose at least 50 m above the summit crater
rim. Due to the increase in activity PHIVOLCS raised the Alert Level to 4
(hazardous eruption possible within days).
On 24 June a series of strong explosions produced ash clouds that rose up
to 1 km above the volcano and drifted to the N. At 1245 a pyroclastic flow
descended about 4 km SE down the Bonga and Buyuan gullies, generating an
ash cloud that ascended to 2.3 km. Beginning at 1644 explosions sent ash
clouds to ~5 km above the summit crater. The largest eruption produced an
ash cloud that rose to 10 km above the volcano. Ash generated from the
pyroclastic flows and from the summit eruptions drifted to the NE towards
the town of Malilipot. PHIVOLCS increased the Alert Level to 5 (hazardous
eruption in progress) and the danger zone was extended from 7 to 8 km in
radius. PHIVOLCS also announced that all areas within the declared danger
zone should be immediately evacuated. The areas at greatest risk were near
the Mabinit, Bonga, Matanag, and Buyuan gullies. After the large eruptions
on 24 June a lull in activity occurred until at least 0630 on 26 June. This
interval was marked by a decrease in seismic activity and only three small
explosions. PHIVOLCS maintained Alert Level 5 due to the possibility of
more explosive volcanic activity.
News agencies reported that ~25,000 residents near the volcano were
evacuated on 24 June. Many returned to their homes the following day
despite the evacuation order. There were no reports of injuries directly
from the eruptions. On 25 June area airports were closed. News articles
noted the possibility that rain from a tropical storm in the area could mix
with ash and generate dangerous lahars. The provincial government declared
a state of calamity in affected areas.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Sources Philippine Institute of Volcanology and Seismology
http//www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Associated Press 6/25
http//news.excite.com/news/ap/010625/00/news-philippines-volcano,
Reuters 6/25
http//news.excite.com/news/r/010625/05/international-philippines-volcano-dc,
Reuters 6/26
http//news.excite.com/news/r/010626/08/international-philippines-volcano-dc
, Associated Press 6/26
http//news.excite.ca/news/cp/010626/06/mayon-volcano-remains
Mayon Reports
http//www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from
the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
During the week two eruptive episodes occurred at Etna’s Southeast Crater.
On 22 June an eruption began after 3 days of low activity. The eruption was
similar to the previous episodes, with lava flowing down the flanks of the
volcano prior to Strombolian activity. Volcanic bombs were thrown 300-400 m
above the crater and lava fountains reached a maximum height of 150 m. An
ash plume rose up to 3 km above the crater. The Toulouse VAAC reported that
the ash plume was visible on Sistema Poseidon’s Etna webcam for ~2 hours,
but not on satellite imagery. The same day very strong degassing was
observed at Bocca Nuova crater. On 24 June another eruptive episode lasted
more than 2 hours.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Source Sistema Poseidon http//www.poseidon.nti.it/,
Toulouse VAAC http//www.ssd.noaa.gov/VAAC/OTH/FR/messages.html,
Charles Rivière’s website,
http//perso.club-internet.fr/rivierec/juin_2001.htm
Etna Reports
http//www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm from
the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Weak glow was visible in the area where lava entered the sea at the E
Kupapa`u entry. Small lava flows were active on the coastal flat at the
base of the Pulama pali scarp. Generally, weak, steady tremor and related
long-period earthquakes continued beneath Kilauea’s caldera. Tremor
remained weak to moderate near Pu`u `O`o and seismicity was at normal
levels elsewhere. Tiltmeters in the summit area and along the east rift
zone indicated no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source US Geological Survey Hawaiian Volcano Observatory
http//hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http//www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
PITON DE LA FOURNAISE Réunion Island, Indian Ocean 21.23°S, 55.71°E; summit
elev. 2,631 m
Tremor associated with the eruption that began on 11 June at Piton de la
Fournaise continued under the volcano’s E flank. Lava fountains were
visible at two vents; at one vent strong degassing occurred, while at the
other vent a boiling lava lake occasionally overflowed, sending lava flows
towards the NE.
Background. The massive Piton de la Fournaise shield volcano on the island
of Réunion is one of the world's most active volcanoes. Most historical
eruptions have originated from the summit and flanks of Dolomieu, a
400-m-high lava shield that has grown within the youngest of three large
calderas. This latter caldera is 8 km wide and is breached to below sea
level on the eastern side. More than 150 eruptions, most of which have
produced fluid basaltic lava flows within the caldera, have been documented
since the 17th century.
Sources Thomas Staudacher and Georges Boudon, Observatoire du Piton de la
FournaiseInstitut de Physique du Globe de Paris,
http//volcano.ipgp.jussieu.fr8080/reunion/Eruptions.htm
Piton de la Fournaise Reports
http//www.volcano.si.edu/gvp/volcano/region03/indian_w/pdlf/var.htm from
the Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC 5 hours)
Volcanic activity at Popocatépetl remained at normal levels, with several
small exhalations of steam, gas, and small amounts of ash. Based on
information from CENAPRED, the Washington VAAC reported that on 24 June at
0900 a small eruption produced an ash cloud that rose ~0.5 km above the
volcano and drifted to the SW.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site) http//www.cenapred.unam.mx/boletines.html
Sources Centro Nacionale de Prevencion de Desastres
http//www.cenapred.unam.mx/boletines.html,
Washington VAAC http//www.ssd.noaa.gov/VAAC/messages.html
Popocatépetl Reports
http//www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html from
the monthly Bulletin of the Global Volcanism Network
SAN CRISTÓBAL Nicaragua 12.702°N, 87.004°W; summit elev. 1,745 m
According to news reports, on 21 June an explosion at San Cristóbal sent an
ash cloud to a maximum height of 800 m. The cloud extended approximately 25
km downwind of the crater and ash fell in the town of Chinandega, ~15 km SW
of the volcano.
Background. The San Cristóbal volcanic complex, consisting of five
principal volcanic edifices, forms the NW end of the Marrabios Range. The
symmetrical 1,745-m-high youngest cone, San Cristóbal itself (also known as
El Viejo), is Nicaragua's highest volcano and is capped by a 500 x 600 m
wide crater. El Chonco, with several flank lava domes, is located 4 km to
the W of San Cristóbal; it and the eroded Moyotepe volcano, 4 km to the NE
of San Cristóbal, are of Pleistocene age. Volcán Casita contains an
elongated summit crater and lies immediately E of San Cristóbal; Casita was
the site of a catastrophic landslide and lahar in 1998. The
Plio-Pleistocene La Pelona caldera is located at the eastern end of the San
Cristóbal complex. Historical eruptions from San Cristóbal, consisting of
small-to-moderate explosive activity, have been reported since the 16th
century. Some other 16th-century eruptions attributed to Casita volcano are
uncertain and may pertain to other Marrabios Range volcanoes.
Sources Instituto Nicaragüense de Estudios Territoriales,
http//www.ineter.gob.ni/geofisica/vol/cristobal/com/20010511/index.html,
La Noticia http//www.lanoticia.com.ni/,
El Nuevo Diario http//www.elnuevodiario.com.ni/,
La Prensa http//www.laprensa.com.ni/
San Cristóbal Reports
http//www.volcano.si.edu/gvp/volcano/region14/nicarag/sancrist/var.htm
from the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
During 15-21 June seismic activity was above background levels. Many small
earthquakes occurred within the volcano’s edifice and episodes of weak
spasmodic volcanic tremor were recorded. Local seismic signals accompanied
explosions, avalanches, and collapses. Weak steam, gas, and ash explosions
rose to a maximum height of 800 m above the lava dome. The level of Concern
Color Code
remained at Yellow.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http//www.avo.alaska.edu/avo4/updates/kvertweekly.htm,
Shiveluch Reports
http//www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
During 15-22 June volcanic activity remained at about the same level as the
previous week. The number of rockfalls increased in comparison to the
previous week, while other types of seismic events generally decreased.
Towards the end of the week the number of rockfalls also decreased
slightly. Growth was still concentrated in the S sector of the lava dome
above the town of Galway’s. Small, near-continuous rockfalls occurred in
the upper part of White River. Sulfur dioxide flux decreased slightly.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source Montserrat Volcano Observatory http//www.mvomrat.com/
Soufrière Hills Reports
http//www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
Based on information from the IG, the Washington VAAC reported that on 22
June at 0630 and 0652 eruptions sent ash clouds to 5.8 and 8.8 km a.s.l.,
respectively. No ash was visible on satellite imagery. Small explosions on
25 June at 0138 and 1328 produced ash clouds that rose ~6 km a.s.l and
drifted to the W. Small amounts of ash were deposited in the town of
Ambato, ~40 km NW of the volcano.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources Instituto Geofísico, http//www.epn.edu.ec/~igeo/index.html,
Washington VAAC http//www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http//www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 471 of 997: Marcia (MarciaH) * Sat, Jun 30, 2001 (21:48) * 61 lines
Another disaster in the making?
State’s pledge to Hawaiians of Kalapana nears fulfillment
The appropriations to develop
new land will help some
displaced families to rebuild
By Bruce Dunford
Associated Press
It has been a decade since the state promised four dozen Hawaiian families displaced by Kilauea's
lava flows through Kalapana in 1990 that they would get a new place for their tightly knit community
to continue their traditional lifestyle.
A law that went into effect yesterday is the latest attempt by the state to keep that promise by paying
for the needed water, roads and other infrastructure.
"To me, I see it as a completion of something we promised a long time ago," said Sen. Jonathan
Chun (D, South Kauai-Niihau), chairman of the Senate Hawaiian Affairs Committee. "I know it
meant a lot to the people 10 years ago, and I think it still does."
A 1938 federal law intending to preserve the unique way of life at one of the last Hawaiian fishing
villages on the Big Island provided that native Hawaiians in Kalapana be given leases for home sites
and fishing rights in the area.
In 1990 the unstoppable rivers of lava that Kilauea began sending out in 1983 wiped out Kalapana,
turning much of the once lush coastal landscape into barren rock. More than 180 homes were
destroyed, including 58 owned by native Hawaiians.
A 1991 state law opened the way for the native Hawaiians displaced at Kalapana to set up a new
community two miles away in the Kikala-Keokea homestead area adjacent to the
Kalapana-Kapoho Beach Road with long-term leases on 1-acre lots.
Forty-eight families who accepted the offer have been waiting patiently for the state to ready the
property and are anxious to get back on the land, which is similar to the Kalapana area they lost,
said Kimo Peleiholani-Blankenfeld.
"We've just been waiting. My mom said as soon as the bill passes, then we'll be able to start
working," said Peleiholani-Blankenfeld, whose mother, Edleen "Aunty Tootsie" Peleiholani, has been
pressing lawmakers for years.
Most of the families remain scattered throughout the Kalapana area "and have stayed in touch,
keeping our community alive," he said.
Some have been planting crops on their designated lots in Kikala-Keokea, and others have begun
preparing driveways and made other preparations, said Peleiholani- Blankenfeld.
The site "allows the Kalapana families to develop the land in a manner that will enable them to
continue their traditional way of life by raising small animals, planting subsistence crops, growing
herbal medicines and gathering additional food resources from the nearby oceans and uplands,"
according to the 1991 law.
It also appropriated $1.75 million for low-interest loans of up to $35,000 for building homes that
were exempt from zoning and building codes provided they meet the minimum requirements for
health and safety. To date, only one loan has been granted.
Making the building costs as low as possible for the families through relaxed building and zoning
codes jeopardized any chance of getting the homeowners insurance required by the banks to qualify
for the loans, Chun said.
Those loans also were jeopardized by the lack of adequate infrastructure to sustain a community, he
said.
The Department of Land and Natural Resources recently completed roads and waterlines to the
subdivision and, with a new appropriation approved by lawmakers, will be able to put roads and
waterlines in the subdivision, Chun said.
A similar bill was approved last year, but Gov. Ben Cayetano vetoed that measure because of
questions over its language and the legality of its appropriation.
Those concerns were resolved in this year's bill, Chun said.
The new measure appropriates $1.75 million from the state to be matched by up to $1.35 million
from the Office of Hawaiian Affairs to complete the needed infrastructure.
If there are no further complications, the Hawaiians could start building and moving in about two
years, Chun said.
Topic 2 of 99 [Geo]: Vulcanism
Response 472 of 997: Marcia (MarciaH) * Sat, Jun 30, 2001 (22:20) * 5 lines
Living downwind of a volcano has its drawbacks. This was taken by me on my birthday because I wanted to be there instead of someplace fancy. How much better than an erupting gentle volcano can it get?! In any case, this is sunset over the fume cloud from Pu'u O'o just out of range to the right and over the pali. Honolulu is downwind. Their horizon looks orange like the ones in Southern California - and Honolulu is 200 miles downwind. When the airflow reverses, Hilo gets it. We are only 30 miles away and advised to stay indoors. It also tarnishes your family silver in short order.
Topic 2 of 99 [Geo]: Vulcanism
Response 473 of 997: Marcia (MarciaH) * Sat, Jun 30, 2001 (22:38) * 5 lines
Lest you think I am alone in this little obsessive adoration of Mme Pele, the volcano Goddess of old Hawaii, let this picture assure you I was not alone. To the extreme right on the distant finger of land there is a small bump. That is a newly-formed littoral cone and the lava was entering the sea at this point.
Topic 2 of 99 [Geo]: Vulcanism
Response 474 of 997: Marcia (MarciaH) * Sun, Jul 1, 2001 (21:28) * 80 lines
from American_Patriot
Canada's Volcanoes-
1) Volcano Mountain, central Yukon Territory, Canada
2) Volcanic Creek, NW British Columbia, Canada
3) Ruby Mountain, NW British Columbia, Canada
4) Cracker Creek cone, NW British Columbia, Canada
5) Ash Mountain, Canada
6) South Tuya, Canada
7) Matthew's Tuya, Canada
8) Tuya Butte, Canada
9) Mt. Edziza, NW British Columbia, Canada
10) Hoodoo Mountain, NW British Columbia, Canada
11) Iskut River, NW British Columbia, Canada
12) Lava Fork, NW British Columbia/SE Alaska
13) Tseax Cone/Aiyansh, Central British Columbia, Canada
14) Nazko Cone, Central British Columbia, Canada
15) Wells Grey, east-central British Columbia, Canada
16) Mt. Meager, SW British Columbia, Canada
17) Mt. Garibaldi, SW British Columbia, Canada
18) Watts Point, SW British Columbia, Canada
America's Volcanoes- (By state)-
Alaska-
1)Adagdak 22)Mageik
2)Aniakchak 23)Moffett
3)Augustine 24)Mr. Wrangell
4)Capital 25)Pavlof & Pavlof Sister
5)Cleveland 26)Pogromni
6)Chiginaga 27)Redoubt
7)Devil's Desk 28)Roundtop
8)Drum 29)Sanford
9)Fisher 30)Segula
10)Frosty 31)Semisopochnoi
11)Gareoli 32)Shishalden
12)Great Sitkin 33)Spurr
13)Griggs 34)Steller
14)Iliamna 35)Tanaga & Takawangha
15)Isanotski 36)Trident
16)Kaguyak 37)Ugashik & Peulik
17)Kanaga 38)Unimak Island
18)Katmai & Novarupta 39)Veniaminof
19)Kialagvik 40)Vsevidoff &
20)Kukak Recheschnoi Volcanoes
21)Little Sitkin 41)Westdahl
42)Yantarni
Arizona-
1)Coliseum Maar 6)San Francisco Mountain
2)Crater 160 7)SP Mountain
3)Merriam Cone 8)Sunset Crater
4)Morale Claim Maar 9)Unikaret Volcanic Field
5)Navajo Volcanic Field
California-
1)Amboy 6)Mono Inyo Craters
2)Cima 7)Pinnacles
3)Lassen Park 8)Pisgah
4)Long Valley Caldera 9)Mt. Shasta
5)Malapi Hill 10)Ubehebe
Hawaii-
1)Diamond Head 8)Loihi Seamount
2)Hanauma 9)Mauna Kea
3)Hualalai 10)Mauna Loa
4)Kahoolawe 11)Maui
5)Kilauea 12)Mahukona
6)Kohala 13)Oahu
7)Koko
Idaho-
1)Menan Buttes
2)Columbia River Flood Basalts
3)Craters of The Moon
Topic 2 of 99 [Geo]: Vulcanism
Response 475 of 997: Marcia (MarciaH) * Sun, Jul 1, 2001 (21:30) * 47 lines
New Mexico-
1)Albuquerque 6)Jornada del Muerto
2)Capulin Mountain 7)McCartys Flow
3)Carrizozo 8)Taos
4)Cerros del Rio 9)Mt. Taylor
5)Jemez 10)San Felipe
Oregon-
1)Battle Ax Mountain 13)Maiden Peak
2)Belknap 14)Mt. Bachelor
3)Boring Lava 15)Mt. Hood
4)Broken Top 16)Mt. McLoughlin
5)Columbia River Flood 17)Newberry Volcano
Basalts 18)Round Butte
6)Crater 19)Strawberry Volcanics
7)Diamond Craters 20)Thielsen, Oregon
8)Devil's Garden 21)Three Fingered Jack
9)Fort Rock Basin 22)Three Sisters
10)Gray Butte 23)Washington, Oregon
11)Jefferson
12)Jordan Craters
South Dakota-
1)Bear Butte
Utah-
1)Fumarole Butte
2)Pavant Butte
Washington-
1)Mt. Adams
2)Baker
3)Columbia River Flood Basalts
4)Glacier Peak
5)Mt. Rainier
6)Mt. St. Helens
Wyoming-
1)Devil's Peak
2)Yellowstone
http://clubs.yahoo.com/clubs/warningvolcanologyactivated
Thanks American_Patriot - this is sensational stuff. In honor of Canada Day and Marican Independence Day...
Topic 2 of 99 [Geo]: Vulcanism
Response 476 of 997: Rob Glennie (AotearoaKiwi) * Mon, Jul 2, 2001 (07:23) * 18 lines
Hi
Here is the New Zealand dirty dozen volcanoes:
Ruapehu (crater lake is notorious for lahars, most infamous destroyed a passenger train killing 151 people on Christmas eve 1953 - and the lake is almost ready to repeat, having nearly refilled after the 1995-96 eruptions)
Ngauruhoe(perfect stratovolcano frequently active, last eruption 1975 - overdue for eruption)
Tongariro(complex andesite volcano last eruption in 1896?)
Taupo (last eruption widely recognised as the world's most violent for 5000 years - no one knows WHEN it will blow next)
Taranaki (perfect stratovolcano with huge ring plain of debris - I call it "the New Zealand Rainier")
Okataina (caldera with record for huge ignimbrite eruptions, plus rhyolite dome building events)
Auckland (48 volcanoes including Rangitoto island - next eruption could come anytime)
Mayor Is.(almost continuously active, last eruption - ash explosion July 2000)
White Is.(dormant island volcano with a caldera)
Tarawera (last eruption 1886 destroyed Pink and White terraces, 3 villages and killed 153 people)
Edgecumbe(last known event 800(0?)years BP)
Tauhara? (little known dacite volcano near Taupo)
Topic 2 of 99 [Geo]: Vulcanism
Response 477 of 997: Cheryl (CherylB) * Mon, Jul 2, 2001 (18:07) * 3 lines
Those are twelve volcanoes that demand respect. Are there other volcanoes as well in New Zealand?
Is there a Maori deity corresponding to the Hawaiian Pele?
Topic 2 of 99 [Geo]: Vulcanism
Response 478 of 997: Marcia (MarciaH) * Mon, Jul 2, 2001 (18:33) * 7 lines
Hmmm... what a vacation that would make... or another one (a much better one, actually, that has been suggested to me...) How many of these have you seen, Rob?
I am wondering why they left Mt Lassen off the California list. I am certain to hear of others if there are corrections. Check your state please! Let us know what is missing or if anything surprises you, please!
Now I know where all those little earthquakes in British Columbia were coming from - lots of volcanoes there.
*Hugs* Rob... thanks for posting!
Topic 2 of 99 [Geo]: Vulcanism
Response 479 of 997: Rob Glennie (AotearoaKiwi) * Tue, Jul 3, 2001 (02:37) * 15 lines
Hi
I have seen all but Taranaki and Mayor Island. I have swum in the caldera of Taupo (Lake Taupo fills the caldera and is an immensely popular holiday spot).
I have landed on White Island in the Bay of Plenty (accessible by small craft and helicopter)where 11 people were killed in 1914 after one side of the crater wall fell in blocking the vent which then emptied violently in a lahar that destroyed a sulphur works - absolutely awesome place, though only the insane would knowingly build a sulphur works there.
Auckland is a huge volcanic field with 48 known events (individual volcanoes - not all still exist)and more are expected. The last eruption from the Auckland field was 700 years ago.
Okataina is a caldera with no distinct rim, and Tarawera is in actual fact three huge rhyolite domes (Wahanga, Ruawahia and Tarawera)within the caldera. Okataina erupts more frequently than Taupo (the other dangerous caldera)and the eruptions vary massively from extrusions of rhyolite, through to full blown caldera events. On June 10, 1886 the three domes of Tarawera erupted in a four hour display of volcanic violence that left the Europeans settlers in shock as they all envisioned a volcano to look like Ruapehu, Ngauruhoe, or Taranaki - not three squat domes in the middle of nowhere.
Ruapehu - don't mention Ruapehu, and I (the owner of Whakapapa and Turoa skifields)didn't wanna know...... lahars, phreatomagmatic eruptions, debris slides - NOOOOOOOOOOOO!!!!
"Mate, what the heck did you expect?!"
No, seriously, lahars pour down the mountain with fair frequency and some have done considerable damage - like the infamous Tangiwai lahar, and Whakapapa kiosk lahar (a night time event which destroyed the kiosk on Whakapapa skifield in 1969). Phreatomagmatic eruptions have caught a few people off guard and can happen as long as magma has a water body to erupt through (crater lake), and are the most frequent catalysts for lahars. Finally debris slides are real too. One slid down the western side of the mountain all the way to the main road bordering the Tongariro National Park on the western side, 9500 years ago burying the land to a depth of several metres.
Ngauruhoe - insolent boy well known for small pyroclastic flows and explosive eruptions. It is an andesite cone that shares the same magma reservoir as Tongariro and is the volcano that (aside from Ruapehu and White Island) is the one I think will erupt next.
Tongariro - cranky old man who hurls rocks down the flanks from any one of it's four craters and now dormant with the expectation it will erupt sometime in the
next few decades.
Taupo - last drunken rage was 1800 years ago and flung from the vent 70 km3 of ignimbrite and maybe 30 km3 of ash and pumice (just go to the lake and pick up the pumice). NO ONE is looking forward to the day when seismograph needles start twitching in an ominous jig that heralds magma movement - not even I am.
Rob
Topic 2 of 99 [Geo]: Vulcanism
Response 480 of 997: Marcia (MarciaH) * Wed, Jul 4, 2001 (14:11) * 73 lines
***********************************************
KVERT Information Release 41-01: July 2, 2001
***********************************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 41-01
Monday, July 2, 2001, 14:10 KDT (23:30 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS YELLOW.
According to visual data from the town of Kluchi at 16:00 KDT (0300 UTC)
on July 1 explosive activity continues and the ash plume rose 1500 m (5000
ft.) above the dome. From 17:00 KDT on July 1 to 1:00 KDT on July 2,
separate shallow earthquakes were recorded. Starting on 1:00 KDT on July 2
(1200 UTC July 1), the number and the energy of earthquakes increased. The
earthquakes became deeper (~ 5 km). At 3:30 KDT on July 2 (1430 UTC July
1), episodes of spasmodic tremor have appeared. Strong earthquakes continue
to occur. At 9:35 KDT on July 2, the volcano was obscured by clouds.
According to reports from Klyuchi, at 11:50 KDT on June 29 (22:50 UTC on
June 28) a short-lived explosion sent an ash-gas plume to a height of 1200
m above the dome or 3700 m (12,000 ft.) ASL. On June 29 at 19:44 KDT
(06:44 Z) another short-lived explosion sent an ash-gas plume to a height
of 1200 m above the dome. Pyroclastic flows about 2.5 - 3km long were
observed. According to seismic data, at 21:40, 22:30, 23:01, 23:18 KDT
(08:40, 09:30, 10:01, 10:18 UTC) on June 29, and at 1:24 KDT and 1:49 KDT
on June 30 (12:24 and 12:49 UTC on June 29), possible ash-gas explosions to
a height 8500 m (28,000 ft.) ASL occurred. Starting at 13:00 KDT small
earthquakes within the volcano's edifice, local seismic signals
(explosions, avalanches, collapses), and episodes of weak spasmodic
volcanic tremor were recorded. The Tokyo VAAC reported that at 3:00 KDT on
June 30 (14:00 UTC on June 29), an ash plume at Sheveluch reached a height
of 7300 m (24,000 ft.) ASL. At 12:00 KDT June 30 (23:00 UTC on June 29),
an ash-poor plume rose 1000 m above the dome (3500 m ASL; 12,000 ft.) and
extended greater than 20 km to the southeast. According to seismic data, at 18:52 KDT
on June 30 (5:52 UTC), a possible ash-gas explosion occurred, and a
7-minute-long shallow seismic event was registered.
GOES satellite data showed a possible small ash cloud drifting over the
Bering Sea, possibly originating in Kamchatka. The cloud was first observed
in GOES imagery at 21:30 KDT (10:30 UTC) on June 30, with a diameter of
approximately 50 km. The cloud continued to drift east and seems to have
dissipated in the central Bering Sea between 6:00 and 8:30 KDT on July 1
(17:00 and 19:30 UTC on June 30), at approximately 500 km north of Amchitka
Island.
According to visual data from Kluchi on July 01 at 12:50 KDT (23:50 UTC
on June 30 Z) a short-lived explosion sent an ash-gas plume to a height of
~8000 m (26,000) ASL. The top part of a mushroom-like plume slowly extended
to the east. Pyroclastic flows have passed downwards on the Baidarnaya
river 5 km. From 13:00 to 17:00 KDT on July 1, weak volcanic tremor and the
local seismic signals (avalanches) were recorded.
GMS satellite imagery showed that a small ash plume appeared over the
volcano at 13:30 KDT (00:30 UTC) on July 1 and began drifting eastward,
while still attached. The easternmost portion of the plume appeared in the
GOES field of view at approximately 16:00 KDT (03:00 UTC). An AVHRR image
at 16:48 KDT (0348 UTC) showed the attached plume to have a high-altitude,
ash-rich portion at approximately 5 km (17,000 ft.) height. The next AVHRR
image at 18:14 KDT (05:14 UTC) revealed that the plume was still attached
but the high-altitude, ash-rich portion had dissipated. The imagery at
20:00 KDT (0700 UTC) had the plume mostly dissipated and difficult to
locate, extending over the western Bering Sea.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Topic 2 of 99 [Geo]: Vulcanism
Response 481 of 997: Marcia (MarciaH) * Wed, Jul 4, 2001 (14:13) * 61 lines
***********************************************
KVERT Information Release 40-01: June 29, 2001
***********************************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 40-01
Friday, June 29, 2001, 12:30 KDT (23:30 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
During the past week (June 22-28), seismic activity was above background
levels. Seven MI>=2 earthquakes, many small earthquakes within the
volcano's edifice, local seismic signals (explosions, avalanches,
collapses), and episodes of weak spasmodic volcanic tremor were recorded.
According to seismic data, at 10:08 on June 22 (21:08 UTC on June 21), a
possible weak ash-gas explosion occurred, and 3-minute-long shallow seismic
event was registered. Starting on 15:00 KDT on June 28, the level of
volcanic tremor and the number of shallow earthquakes increased. In
satellite images at 07:16 KDT on June 26 (18:16 UTC on June 25) a weak
thermal anomaly was observed, accompanied by a small steam plume extending
15 km to the west of the volcano. A small steam plume was also observed in
satellite images at 17:10 and 17:58 KDT (04:10 and 04:58 UTC) on June 28
extending for 50 km to the southeast from the volcano. Clouds obscured the
volcano the entire week.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
During most of the week, seismic activity was at background levels. On June
28, four strong (MI>=2) shallow earthquakes were registered. Since June 23,
episodes of weak spasmodic volcanic tremor were recorded. In the evening of
June 28, a gas and steam plume rose 100 m above the dome. At other times,
clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Several shallow earthquakes (Ml>=1.5) occurred under the volcano during the
week. Clouds obscured the volcano the entire week.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On June 23-24, both volcanoes were quiet. Clouds obscured the volcanoes the
rest of the week. Seismic activity was at background levels. Weak spasmodic
volcanic tremor was registered.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Topic 2 of 99 [Geo]: Vulcanism
Response 482 of 997: Marcia (MarciaH) * Wed, Jul 4, 2001 (15:06) * 4 lines
Great tender Hugs of Aloha for such a wonderful rundown on your volcanoes on New Zealand. It is abundantly apparent that you not only love your Triple Star Islands nation, you also knows her very heart-beat. You and my son have been swimming in a caldera. I have not. *sigh* White Island is notoriously quake-prone from all of the posts I gave logged online. I think not being on it is the most secure way to see it. Nooooooooo, I agree with you on Ruapehu, that is one terrifying disaster waiting to happen. That is one very Big Bad Wolf of a volcano!
For those interested in watching Ruapehu volcan, (it is currently inactive since the mountain is quiet, but they have a lovely shot on camera.)
http://www.cybercorp.co.nz/ruapehu/
Topic 2 of 99 [Geo]: Vulcanism
Response 483 of 997: Marcia (MarciaH) * Wed, Jul 4, 2001 (21:43) * 22 lines
**********************************
TOMS Volcanic Emissions Web Page
**********************************
From: Simon Carn
The Total Ozone Mapping Spectrometer (TOMS) Volcanic Emissions group website
(http://skye.gsfc.nasa.gov) is now being regularly updated with images of
sulfur dioxide and volcanic ash/aerosol clouds as seen by the TOMS
instruments. Images from most of the eruptions detected by Earth Probe TOMS
since 1996 are now online (http://skye.gsfc.nasa.gov/archives.html) and more
will be added in due course. Images can be accessed via the 'Archives' link.
The site will also be updated as our sulfur dioxide and aerosol retrieval
techniques evolve.
^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~
Simon A. Carn TOMS Volcanic Emissions Group
Joint Center for Earth Systems Technology (NASA/UMBC)
University of Maryland Baltimore County
Academic IV-A Room 114J, 1000 Hilltop Circle
Baltimore, MD 21250
USA
Topic 2 of 99 [Geo]: Vulcanism
Response 484 of 997: Marcia (MarciaH) * Fri, Jul 6, 2001 (15:21) * 194 lines
Volcano Watch - July 5, 2001
Where does Kilauea erupt most often?
A visitor recently asked, "Does Kilauea erupt more often at the summit or
along its two rift zones?" Let's try to answer that question.
The summit is a relatively small area, only about 7 km (4 miles) across,
including the caldera and its five pit craters, Halema`uma`u, Keanakako`i,
the double crater of Kilauea Iki, and arguably Lua Manu. Eruptions take
place almost anywhere within this area.
In contrast, the southwest rift zone extends about 30 km (18 miles) from
the summit, and the east rift zone reaches out some 125 km (75 miles), 50
km (30 miles) on land and 75 km (45 miles) below sea level. Eruptions occur
only along linear fissures, so that the active part of each rift zone is
long and narrow. Eruptions along the rift zones tend to be larger than
those at the summit, so that the rift zones produce most of the lava
erupted at Kilauea.
Eruptions are more concentrated at the summit than in any comparably sized
area of the rift zones. That is the reason that the summit is the summit;
it stands high because more lava flows have been erupted there.
One might think that more eruptions have taken place along the entire
length of the rift zones than at the summit, because they are so long. It
might take more eruptions to build a rift zone tens of kilometers (miles)
long than it does to make the summit a bit higher than the rest of the
volcano.
Can these ideas be substantiated by the past two centuries of eruptive
activity?
During the 19th century, the summit had four or five eruptions,
continuously in Halema`uma`u and briefly on Byron Ledge (1832, 1877) and in
Kilauea Iki (1868). An eruption in Keanakako`i in 1877 could have been the
same as the one on Byron Ledge.
Three or four flank eruptions took place during the same time: southwest
rift zone (1823 and 1868), east rift zone (1840), and a questionable brief
submarine event along the lower east rift zone (1884).
The number of eruptions, then, was about the same at the summit and on the
flank. The total volume erupted on the flank is much larger, however--a
little more than 0.2 cubic kilometers (200 million cubic yards) compared
with less than 0.01 cubic kilometer (10 million cubic yards) at the summit.
The summit produced only 5 percent or less of the volume erupted from the
rift zones.
During the 20th century, the summit erupted 22 times, 14 times in
Halema`uma`u, once in Kilauea Iki, and the rest from fissures on the
caldera floor, several of which intersected Halema`uma`u.
The rift zones erupted 24 times, twice together with a summit eruption. All
of the flank eruptions were along the east rift zone, except for three
along the upper southwest rift zone in 1919, 1971, and 1974.
Again, the numbers of eruptions are about the same, but the volumes quite
different. During the 20th century, the flank erupted more than 2.2 cubic
kilometers (2.2 billion cubic yards). The summit added about 0.15 cubic
kilometers (150 million cubic yards) to the surface, only 7 percent of the
flank output.
This examination shows that the past two centuries have probably been
representative of Kilauea's history in terms of the relative volumes
erupted at the summit and along the rift zones. The concentration of
eruptions in the small summit area is clear. Surprisingly, however, the
number of eruptions along the rift zones is no more than at the summit.
If the last two centuries are typical--a big 'if,' given the known episodes
of past caldera collapse and filling--then most of Kilauea's eruptions may
not take place along its rift zones. The summit may actually erupt about as
often as the flank does, although in much smaller eruptions.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u `O`o
vent during the past week. Lava moves away from the vent toward the ocean
in a network of tubes and descends Pulama pali in three separate areas.
Lava in the western tube system is mainly inflating the flow field in the
coastal flats area between the base of the pali and Kamokuna. Inflation of
the flow field near Royal Gardens is from lava in the eastern tube system.
Lava in the central tube system feeds the ocean entry. Lava continued to
enter the ocean in the area east of Kupapa`u throughout the week. Surface
flows, primarily ooze-outs in the inflating areas, are occasionally seen in
the coastal flats.
There were no earthquakes reported felt during the week ending on July 5,
2001.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
PO Box 51, Hawaii National Park, HI 96718 Phone (808) 967-7328 FAX (808)
967-8890
Kamchatkan Volcanic Activity INFORMATION RELEASE 42-01
Friday, July 6, 2001, 14:50 KDT (01:50 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS ORANGE.
Seismic activity was above background levels the past week, and
considerably above background levels June 29-July 1. Eighteen MI> =2 and one
MI> =3 earthquakes, many small earthquakes within the volcano's edifice,
local seismic signals (explosions, avalanches, collapses), and episodes of
weak spasmodic volcanic tremor were recorded. On June 28-29 and July 2-4,
3-minute-long shallow seismic events were registered. According to visual
data from Klyuchi, at 08:00 KDT on June 29 (19:00 UTC on June 28), the dome
first observed on May 12 was bigger and broader with an intense gas and
steam plume 1000 m above the dome. At 11:50 KDT (22:50 UTC on June 28) and
at 19:44 KDT (06:44 UTC) on June 29 explosions sent ash 1200 m above the
dome (12,000 ft ASL) and short pyroclastic flows 2.5-3.0 km long.
According to seismic data, at 21:40, 22:30, 23:01, 23:18 KDT (08:40,
09:30,10:01,10:18 UTC) on June 29, and at 1:24 KDT and 1:49 KDT on June 30
(12:24 and 12:49 UTC on June 29), possible ash-gas explosions ~6000 m above
the dome (8500 m ASL; 28,000 ft.) occurred. According to a Tokyo VAAC
report, at 3:00 KDT on June 30 (14:00 UTC on June 29), an ash plume rose to
a height of 24,000 ft. ASL. At 12:00 KDT June 30 (23:00 UTC on June 29), an
ash-poor plume rose 1000 m above the dome (3500 m ASL; 12,000 ft.)
extending > 20 km to the southeast. According to seismic data, at 18:52
KDT on June 30 (5:52 UTC), a possible ash-gas explosion occurred, and a
7-minute-long shallow seismic event was registered.
Observers in Klyuchi town reported that on July 01 at 12:50 KDT (23:50
UTC on June 30 Z) a short-lived explosion sent an ash-gas plume ~8000 m
above the dome (35,000 ft. ASL). The top part of a mushroom-like plume
slowly extended to the east. Powerful pyroclastic flows passed downwards on
the Baidarnaya river 5 km. According to visual data from Klyuchi, at 15:30
KDT (02:30 UTC) and 16:00 KDT (03:00 UTC) on July 01 ash plumes rose 1500 m
above the dome extended > 20 km east. Starting on 1:00 KDT (12:00 UTC on
July 01) on July 2, the number and the energy of earthquakes increased. The
earthquakes became deeper (~ 5 km) and strong earthquakes continued to
occur. According to visual data from Ushkovsky volcano, on July 2 the ash
plume rose ~7000-8000 m above the dome (31,000 ? 35,000 ft. ASL). Sometimes
a powerful pulse of ash would course upwards above the dome.
GMS satellite imagery showed that a small ash plume appeared over the
volcano at 13:30 KDT (00:30 UTC) on July 1 and drifted east. On July 3, 4
and 5 voluminous gas and steam plumes 2000-2500 m high were observed.
According to satellite report, on July 02 the thermal anomaly at Sheveluch
was 2 pixels in size at 32 to 35 degrees C with a 5 degree background. On
July 3, a 3 pixel anomaly was seen at Sheveluch; temperatures were 33 to 38
degrees C with a background near 7 degrees C
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels. On June 30 and on July 1, 3 and
4 a gas and steam plume rose 50-100 m above the dome. At other times,
clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity was registered under the volcano. Clouds obscured the volcano
the entire week.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On June 30 and July 2 and 3 both volcanoes were quiet. Clouds obscured the
volcanoes the rest of the week. Seismic activity was at background levels.
Weak spasmodic volcanic tremor was registered.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
907-786-7497
Carolyn Bell
Public Affairs Specialist
U.S. Geological Survey
Mail Stop 119 National Center
Reston, VA 20192
Topic 2 of 99 [Geo]: Vulcanism
Response 485 of 997: Cheryl (CherylB) * Sun, Jul 8, 2001 (14:55) * 1 lines
I saw so footage on the news of Mt. Etna which is currently errupting. They said that no one was endangered so far. It was also mentioned that Etna was about a half-million years old and had been active the entire time.
Topic 2 of 99 [Geo]: Vulcanism
Response 486 of 997: Marcia (MarciaH) * Sun, Jul 8, 2001 (17:39) * 7 lines
I know - and Mt Etna Web cam is broken!
For Sandi, this is Halwmaumau firepit in the center of Kilauea Crater. It is currently not active as the eruptive activity in restricted to the flank of the volcano.
Topic 2 of 99 [Geo]: Vulcanism
Response 487 of 997: Marcia (MarciaH) * Mon, Jul 9, 2001 (19:41) * 89 lines
*********************************
KVERT Information Release 42-01:
July 6, 2001
*********************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 42-01
Friday, July 6, 2001, 14:50 KDT (01:50 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS ORANGE.
Seismic activity was above background levels the past week, and
considerably above background levels June 29-July 1. Eighteen MI > 2 and one
MI > 3 earthquakes, many small earthquakes within the volcano's edifice,
local seismic signals (explosions, avalanches, collapses), and episodes of
weak spasmodic volcanic tremor were recorded. On June 28-29 and July 2-4,
3-minute-long shallow seismic events were registered. According to visual
data from Klyuchi, at 08:00 KDT on June 29 (19:00 UTC on June 28), the dome
first observed on May 12 was bigger and broader with an intense gas and
steam plume 1000 m above the dome. At 11:50 KDT (22:50 UTC on June 28) and
at 19:44 KDT (06:44 UTC) on June 29 explosions sent ash 1200 m above the
dome (12,000 ft ASL) and short pyroclastic flows 2.5-3.0 km long.
According to seismic data, at 21:40, 22:30, 23:01, 23:18 KDT (08:40,
09:30,10:01,10:18 UTC) on June 29, and at 1:24 KDT and 1:49 KDT on June 30
(12:24 and 12:49 UTC on June 29), possible ash-gas explosions ~6000 m above
the dome (8500 m ASL; 28,000 ft.) occurred. According to a Tokyo VAAC
report, at 3:00 KDT on June 30 (14:00 UTC on June 29), an ash plume rose to
a height of 24,000 ft. ASL. At 12:00 KDT June 30 (23:00 UTC on June 29), an
ash-poor plume rose 1000 m above the dome (3500 m ASL; 12,000 ft.)
extending > 20 km to the southeast. According to seismic data, at 18:52
KDT on June 30 (5:52 UTC), a possible ash-gas explosion occurred, and a
7-minute-long shallow seismic event was registered.
Observers in Klyuchi town reported that on July 01 at 12:50 KDT (23:50
UTC on June 30 Z) a short-lived explosion sent an ash-gas plume ~8000 m
above the dome (35,000 ft. ASL). The top part of a mushroom-like plume
slowly extended to the east. Powerful pyroclastic flows passed downwards on
the Baidarnaya river 5 km. According to visual data from Klyuchi, at 15:30
KDT (02:30 UTC) and 16:00 KDT (03:00 UTC) on July 01 ash plumes rose 1500 m
above the dome extended > 20 km east. Starting on 1:00 KDT (12:00 UTC on
July 01) on July 2, the number and the energy of earthquakes increased. The
earthquakes became deeper (~ 5 km) and strong earthquakes continued to
occur. According to visual data from Ushkovsky volcano, on July 2 the ash
plume rose ~7000-8000 m above the dome (31,000 ? 35,000 ft. ASL). Sometimes
a powerful pulse of ash would course upwards above the dome.
GMS satellite imagery showed that a small ash plume appeared over the
volcano at 13:30 KDT (00:30 UTC) on July 1 and drifted east. On July 3, 4
and 5 voluminous gas and steam plumes 2000-2500 m high were observed.
According to satellite report, on July 02 the thermal anomaly at Sheveluch
was 2 pixels in size at 32 to 35 degrees C with a 5 degree background. On
July 3, a 3 pixel anomaly was seen at Sheveluch; temperatures were 33 to 38
degrees C with a background near 7 degrees C
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels. On June 30 and on July 1, 3 and
4 a gas and steam plume rose 50-100 m above the dome. At other times,
clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity was registered under the volcano. Clouds obscured the volcano
the entire week.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On June 30 and July 2 and 3 both volcanoes were quiet. Clouds obscured the
volcanoes the rest of the week. Seismic activity was at background levels.
Weak spasmodic volcanic tremor was registered.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Topic 2 of 99 [Geo]: Vulcanism
Response 488 of 997: Marcia (MarciaH) * Tue, Jul 10, 2001 (22:46) * 74 lines
********************************
Piton de la Fournaise, Reunion
********************************
From: Thomas Staudacher
Piton de la Fournaise
The eruption which started on June 11 stopped on July 7 in the afternoon
after one week of increasing tremor activity. Lava flows in the "Grand
Brûlé" cut the national road 2 on two sites with 100 and 80 m large and 4
to 5 m high aa type flows. The final lava is characterized by abundant
occurence of olivines of 5 to 10 vol%.
On July 7, tremor was particularly high (as high as in the first hour of
eruption). At 1457 (local time) tremor saturated on all stations and
dropped down within 30 seconds to less than 5% of its value. In the next
few hours tremor stopped completely.
Thomas Staudacher
==========================================
Thomas Staudacher
Observatoire Volcanologique du Piton de la Fournaise
Institut de Physique du Globe de Paris
14 RN3, le 27ème
97418 La Plaine des Cafres
La Réunion
tél.: 02 62 27 52 92
fax.: 02 62 59 12 04
********************
Mayon, Philippines
********************
From: Dan Shackelford
Mayon eruption appears to be waning or over.
Following the large eruption of 24 June, Mayon's activity quickly decayed.
Following several days of ashy puffs and lava "trickling" down Bonga
Gulley, the eruption appears to be virtually over. The edifice is
deflating, seismicity decreasing, no further eruptions or lava extrusion
for days now. Secondary activity, though, is still a real possibility as
collapses may occur or rains may enter hot deposits.
From the 7 July Mayon Bulletin
(http://www.phivolcs.dost.gov.ph/vmepd/mayon_bulletin.htm):
Mayon Volcano Bulletin
07 July 2001
8:00 A.M.
Mayon’s activity was quiet for the past 24 hours as the network recorded
only fourteen (14) low frequency volcanic earthquakes associated with
shallow magma movement and nine (9) rockfall-induced high frequency short
duration harmonic tremors. Ground deformation data indicated the volcanic
cone is still slightly inflated but is showing a deflationary trend.
Sulfur dioxide emission was at 2,670 tonnes/day. Crater glow was at fair
intensity (Intensity 2) due to residual heat and only occasional rolling of
incandescent rocks from the summit was observed.
Based on the seismic, ground deformation, gas emission and observational
monitoring data Mayon’s activity is slowly waning. Alert 4 is maintained
however due to the possibility of minor ash puffs and secondary explosions
caused by the contact of water with the voluminous hot lavas. These
explosions can produce pyroclastic flows and rock avalanches but these are
only expected to fall well within the delineated danger zones. The public
is therefore reminded not to venture within the six (6) kilometer-radius
Permanent Danger Zone (PDZ) and the seven (7) kilometer Extended Danger
Zone (EDZ) in the southeast sector. During heavy rainfall, even when the
volcano has finally quieted down, residents along the major river channels
around Mayon are advised to be alert for possible lahar flows and should
take the necessary precautions.
PHIVOLCS
Topic 2 of 99 [Geo]: Vulcanism
Response 489 of 997: Marcia (MarciaH) * Tue, Jul 10, 2001 (22:47) * 56 lines
*******************************
MVO weekly report, 6 July 2001
*******************************
From: Peter Dunkley
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 29 June 2001 to midday, 6 July 2001
Activity at the Soufrière Hills Volcano has continued at a similar level
to that of the previous week. The seismograph network recorded 295
rockfall signals, 28 long period events, 10 long period rockfalls, 4
hybrid events and 1 volcanotectonic earthquake.
No clear views of the upper parts of the volcano were seen during the
week, due to low cloud and ashy conditions, although growth of the dome
still appears to be concentrated on the southern side above White River.
Near-continuous rockfall activity has occurred in the upper part of
White River, although most of the events were small.
Two notable events occurred during the week. A prolonged period of
rockfall activity, involving about half a million cubic metres of
material, occurred on the morning of 30 June down the northern side of
the talus apron in the Tar River valley. The other notable event
occurred on the evening of 4 July, when two small pyroclastic flows
passed down the western flanks of the volcano in the Amersham area,
stopping slightly over a kilometre short of the sea.
A sulphur dioxide flux of 120 tonnes per day was measured on 29 June.
Following the pyroclastic flows in the Amersham area, the daytime entry
zone (DETZ) has been closed until further notice. Activity could
increase quite suddenly, with a dangerous situation developing very
quickly. Ash masks should be worn in ashy conditions. The Belham Valley
should be avoided during and after heavy rainfall due to the possibility
of mudflow activity.
Residents of Montserrat and visitors to the island are advised to tune
into ZJB Radio for up-to-date information on the volcano. Access to
Plymouth, Bramble airport and beyond is prohibited. There is a maritime
exclusion zone around the southern part of the island that extends two
miles beyond the coastline from Trant's Bay in the east to Garibaldi
Hill on the west coast.
The directorship of the MVO changed on 2 July, when Dr Peter Dunkley
replaced Dr Gill Norton, the outgoing Director.
12 noon, Friday, 6 July 2001
Peter Dunkley
Montserrat Volcano Observatory
Mongo Hill
Montserrat
West Indies
Topic 2 of 99 [Geo]: Vulcanism
Response 490 of 997: Marcia (MarciaH) * Tue, Jul 10, 2001 (23:57) * 14 lines
*****************************
Kilauea Update 10 July 2001
*****************************
0535 July 10, 2001
For the first time since June 15, surface lava is visible on Pulama pali this morning at 0447. The crowd-pleasing narrow orange stream arcs gracefully down the pali, from top to bottom, entirely within the confines of the western half of the flow field. The breakout point for this stream is not known.
Yesterday morning at 1000-1015, a pilot reported a breakout about 400 m above the top of the pali. The stream extended down the pali to the coastal flat, where the pahoehoe changed to `a`a. The pilot reported the lava is on the east side of the flow field. This morning's flow is in the middle to western side of the field. It is not clear if the two flows are the same.
Pu`u `O`o's crater is obscured by thick fume this morning.
Weak, rather steady tremor and a few related long-period earthquakes continue beneath Kilauea's caldera. Near Pu`u `O`o, the tremor alternates from weak-moderate to strong over periods of several hours--out of sync with the audible sounds heard from the crater, with periods of minutes to tens of minutes. Elsewhere, seismicity is at normal levels. Tiltmeters across the volcano show no significant deformation and in fact are nearly board-flat at Kilauea's summit.
Topic 2 of 99 [Geo]: Vulcanism
Response 491 of 997: Marcia (MarciaH) * Wed, Jul 11, 2001 (22:25) * 261 lines
GVP/USGS Weekly Volcanic Activity Report 4-10 July 2001
http://www.volcano.si.edu/gvp/usgs/index.htm
New Activity/Unrest: | Mayon, Philippines |
Ongoing Activity: | Etna, Italy | Kilauea, USA | Piton de la Fournaise,
Réunion Island | Popocatépetl, México | Semeru, Indonesia | Shiveluch,
Russia | Soufrière Hills, Montserrat | Tungurahua, Ecuador |
New Activity
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
A decrease in volcanic activity began on 3 July that led PHIVOLCS to reduce
the Alert Level on 4 July from 5 (hazardous eruption in progress) to 4
(hazardous eruption imminent). In comparison to the previous week SO2
emissions decreased, seismic activity was lower, the rate of inflation of
the volcano’s edifice decreased, and there was no ash in the steam clouds
that emanated from the crater. Alert Level 4 was maintained due to the
possibility of minor ash puffs and secondary explosions caused by the
contact of water with the voluminous hot lava. The extended danger zone was
reduced from 8 km to 7 km in radius. On 4 July ~20,000 people who were
evacuated from the most distal parts of the evacuation zone were permitted
to return to their homes.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Sources: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Associated Press
http://news.excite.com/news/ap/010704/00/int-philippines-volcano
Mayon Reports
http://www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from
the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
After 4.5 days of low-level activity at Etna, an eruption occurred at
Southeast Crater on 4 July that lasted for approximately 5 hours. The
episode began with lava flowing from the NNE vent towards the NE and SSE
and was followed by modest Strombolian activity. At the summit vent
powerful explosions sent an incandescent fountain up to 400-500 m high and
several large magma bubbles burst sending fragments to the base of the
Southeast Crater cone. A dense tephra column rose from the summit vent and
deposited ash on Etna’s SE flank. Fine ash and 3- to 5-mm-long Pele’s hair
fell as far as the town of Acireale, ~20 km SE of the volcano. On 7 July
another eruptive episode lasted for approximately 1 hour at Southeast
Crater. The episode consisted of lava flows and the eruption of black ash
and small volcanic blocks that reached a height of ~1 km above the volcano
and drifted to the E.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Sources: Italy’s Volcanoes http://www.geo.mtu.edu/~boris/ETNA_news.html,
Charles Rivière's web site,
http://perso.club-internet.fr/rivierec/juillet_2001.htm
Etna Reports
http://www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm from
the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Small surface flows of pahoehoe lava were located in the W and E branches
of the lava flow field. Like the previous week, lava poured into the sea at
the E Kupapa`u ocean entry. Generally, weak, steady tremor and related
long-period earthquakes continued beneath Kilauea's caldera. Tremor
remained weak to moderate near Pu`u `O`o and seismicity was at normal
levels elsewhere. Tiltmeters in the summit area and along the east rift
zone indicated no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http://www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
PITON DE LA FOURNAISE Réunion Island, Indian Ocean 21.23°S, 55.71°E; summit
elev. 2,631 m
The eruption that started on 11 June stopped on 7 July after 1 week of
increased tremor. On 3 July tremor and the intensity of local earthquakes
increased. The earthquakes had magnitudes less than 3 and were located
under Dolomieu crater at a depth near sea level. On 6 and 7 July two aa
lava flows in the Grand Brûlé area crossed the national highway. On 7 July
the end of the eruption was marked by the disappearance of the tremor and a
dramatic decrease in the intensity of local earthquakes.
Background. The massive Piton de la Fournaise shield volcano on the island
of Réunion is one of the world's most active volcanoes. Most historical
eruptions have originated from the summit and flanks of Dolomieu, a
400-m-high lava shield that has grown within the youngest of three large
calderas. This latter caldera is 8 km wide and is breached to below sea
level on the eastern side. More than 150 eruptions, most of which have
produced fluid basaltic lava flows within the caldera, have been documented
since the 17th century.
Sources: Observatoire Volcanologique du Piton de la Fournaise
http://volcano.ipgp.jussieu.fr:8080/reunion/Eruptions.htm
Piton de la Fournaise Reports
http://www.volcano.si.edu/gvp/volcano/region03/indian_w/pdlf/var.htm from
the Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC 5 hours)
On 3 July at 0410 and 0648 moderate-sized explosions occurred. The latter
explosion lasted about 10 minutes and produced an ash cloud that rose ~4 km
above the volcano. Initially the cloud drifted to the SE and later the
highest portion of the cloud drifted to the NE. Based on information from
pilot reports and ground observations, the Washington VAAC reported that
the ash cloud was 9.3 km SE of Mexico City Airport at 0930. Ashfall
occurred in several towns including Chalco, ~35 km NW of the volcano, and
there were reports of light ashfall on the airport’s runways.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Sources: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Associated Press http://www.latimes.com/news/nation/20010704/t000055087.html,
CNN http://www.cnn.com/2001/WORLD/americas/07/03/mexico.volcano.ap/index.html
Popocatépetl Reports
http://www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html from
the monthly Bulletin of the Global Volcanism Network
SEMERU Java, Indonesia 8.11°N, 112.92°E; summit elev. 3,676 m; All times
are local (= UTC + 7 hours)
Based on information from pilot reports and the Meteorological and
Geophysical Agency of Indonesia, the Darwin VAAC reported that on 8 July at
1503 a SE-drifting ash plume rose to ~2.5 km above the volcano. Ground
based reports prior to the eruption revealed that each day during 18-24
June Semeru emitted ash to ~0.6 km above the volcano.
Background. Semeru is the highest volcano on Java and one of its most
active. The symmetical stratovolcano rises abruptly to 3,676 m above
coastal plains to the S and lies at the southern end of a volcanic massif
extending N to the Tengger caldera. Semeru has been in almost continuous
eruption since 1967. Frequent small-to-moderate Vulcanian eruptions have
accompanied intermittent lava dome extrusion, and periodic pyroclastic
flows and lahars have damaged villages below the volcano. A major secondary
lahar on 14 May 1981 caused more than 250 deaths and damaged 16 villages.
Source: Darwin VAAC http://www.bom.gov.au/info/vaac/advisories.shtml
Semeru Reports
http://volcano.si.edu/gvp/volcano/region06/java/semeru/var.htm from the
monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
During 29 June to 6 July seismic activity remained above background levels,
but the level of explosive volcanic activity decreased in comparison to the
previous week. On 2 and 3 July a thermal anomaly was visible on satellite
imagery. On 3, 4, and 5 July voluminous gas-and-steam plumes rose 2-2.5 km
above the volcano. Due to the decrease in volcanic activity the Concern
Color Code http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm at
Shiveluch was reduced from Orange to Yellow.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
During 29 June to 6 July volcanic activity at Soufrière Hills remained
similar to the previous week. Lava dome growth appeared to still be
concentrated on the S side of the dome above the White River. On 30 June a
large number of rockfalls traveled down the N side of the talus apron in
the Tar River. On 4 July two small pyroclastic flows traveled down the
volcano’s W flank in the Amersham area. The Washington VAAC reported that
on 4 July an ash cloud rose ~3 km a.s.l. and drifted to the WNW. Also, on
10 July numerous rockfalls produced W-drifting ash plumes that did not
exceed ~3 km a.s.l. in height.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
http://www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
During 3-8 July several small-to-moderate eruptions produced ash clouds.
One of the larger eruptions occurred on 5 July at 1310, producing an ash
cloud that a pilot reported rose to ~7.6 km a.s.l. However, satellite
imagery and additional information suggested that the dense SE-drifting ash
cloud rose to ~9 km a.s.l.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http://www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Topic 2 of 99 [Geo]: Vulcanism
Response 492 of 997: Marcia (MarciaH) * Wed, Jul 11, 2001 (23:04) * 49 lines
****************************************************
Sabbatical Replacement at University of Hawaii Hilo
****************************************************
From: Ken Hon
The University of Hawai`i at Hilo (UHH) Geology Department has an opening
for a visiting professor to teach introductory geology courses during Fall
2001 with a possible extension to Spring 2002. The position is a temporary
sabbatical replacement. We apologize for the very short notice. If you
are interested please email a vitae (a short vitae is fine) outlining your
teaching and other relevant experience to Dr. Jene Michaud, Geology
Department Chair (jene@hawaii.edu). Please also include a brief statement
of teaching philosophy. A Ph.D. in the Earth sciences is required.
Materials should be submitted by July 17, 2001.
UHH is a small 4 year liberal arts university located on the Island of
Hawai`i in the small town of Hilo (population ~50,000). The Hawaiian
Volcano Observatory and Kilauea volcano are short drives from Hilo. More
information about our program can be found on the Geology Department
website at http://www.uhh.hawaii.edu/~geology/
Ken Hon
Assistant Professor of Geology
University of Hawaii at Hilo
200 W. Kawili Street
Hilo, HI, 96720
808-974-7302
*********************************
Volcanic eruptions of the 1930s
*********************************
From: JohnDaybreak@aol.com
I am a student in England, attempting to produce a document 'A Century of
Volcanoes'; this includes data on Mont Pelee, Katmai, Paricutin, Surtsey, St.
Helens, Pinatubo and Kilauea. However, one decade I can find little data on
is the 1930s. If any of the members know of volcanic events in the 1930s,
wherever in the world they may be, I would definitely be interested; the more
detailed, the better. Mayon and Rabaul were active in this period, I know,
but data on the internet concerning these events is scarce and usually
eclipsed by the more recent eruptions of those two volcanoes, with data
confined to an occasional reference.
Thanks for the help; could all comments please be addressed to
'JohnDaybreak@aol.com'. My name is actually Tom Bacon, but that's a
colourful e-mail address! Thanks!
** please respond to Tom directly at JohnDaybreak@aol.com; please do not
reply to the volcano list **
Topic 2 of 99 [Geo]: Vulcanism
Response 493 of 997: Marcia (MarciaH) * Thu, Jul 12, 2001 (19:54) * 61 lines
********************************************
Possible eruptions - Semeru and the Kuriles
********************************************
From: Dan Shackelford
Possible eruptions at Semeru and in the Kurile Islands?
Volcanic ash advisories suggest a brief plume at Semeru (Indonesia) to ~6
km a.s.l. on 9 July (based on aircraft reports, satellite imagery shows no
plume) and possible ash event in the Kurile Islands on the 9th to ~12 km
a.s.l. (aircraft report, not confirmed in satellite imagery). Note that
Semeru has been continuously active since 1967.
From http://www.bom.gov.au/products/Volc_ash_latest.shtml
Received FVAU0170 at 08:58 UTC, 09/07/01 from ADRM
VOLCANIC ASH ADVISORY
ISSUED 0857 UTC 9 JULY 2001 BY DARWIN VAAC
VOLCANO: SEMERU 0603-30= Java 8.108S 112.92 E [S08 06.5 E112 55.2]
SUMMIT HEIGHT: 3676 M [12061FT]
INFORMATION SOURCE: QANTAS Airep, Meteorological and Geophysical
Agency of Indonesia, satellite imagery.
ERUPTION DETAILS: Ash plume reported to FL200 at 080310 UTC, drifting
SE. Report received at 080857 UTC.
ASH CLOUD: Visibility remains good over the region. No plume has been
evident today on visible imagery and only afternoon cloud could be
detected. There is also no evidence of ash cloud on enhanced imagery.
TRAJECTORY: Any plumes between FL120 and FL200 are expected to drift
towards the southwest to southeast quadrant at 10 knots.
FORECAST: Nil
NEXT ADVICE: No further advices will be issued unless significant new
information is received. The area will continue to be closely
monitored.
DARWIN VAAC.
----------------------------------------------------------------
VOLCANIC ASH ADVISORIES FROM TOKYO VAAC - LAST 24 HOURS
DARWIN VAAC 21:12 UTC, 10/07/2001
--------------------------------------------------------------------
Received FVFE01 at 23:55 UTC, 09/07/01 from RJTD
VOLCANIC ASH ADVISORY NUMBER 1
ISSUED 2355UTC 9 JULY 2001 BY TOKYO VAAC.
ASH CLOUD IN KURIL IS E-OFF 46.2N 156.4E.
SOURCE: GMS-5, AIREP.
VOLCANIC ASH AT FL380 AT 2200UTC 9 JULY 2001 WAS REPORTED.
ASH CLOUD CAN NOT BE DETECTED ON SATELLITE IMAGERY.
NO FURTHER ADVISORY WILL BE ISSUED UNLESS NEW SIGNIFICANT INFORMATION
IS AVAILABLE.
Topic 2 of 99 [Geo]: Vulcanism
Response 494 of 997: Marcia (MarciaH) * Thu, Jul 12, 2001 (20:32) * 6 lines
I do not speak or read French very well, but do look at this page and
scroll all the way down. Too bad Etna cam was broken all this time!
http://perso.club-internet.fr/rivierec/juillet_2001.htm
Topic 2 of 99 [Geo]: Vulcanism
Response 495 of 997: Marcia (MarciaH) * Fri, Jul 13, 2001 (14:24) * 196 lines
Volcano Watch - July 12, 2001
Pu`u `O`o changes steadily and abruptly
The ground surface subsided abruptly about six weeks ago at Pu`u
`O`o, Kilauea Volcano's active cinder-cone vent. Gaping cracks opened
around the edges of the subsidence zone, centered on the southwest edge of
the cone. A collapse pit about 30 m (100 ft) in diameter and 15 m (50 ft)
deep nibbled into the cone's margin. A second collapse pit continues to
deepen within the floor of Pu`u `O`o's crater. One large rock slide and
several smaller ones ensued.
Many of these structures likely formed within a short period of time,
perhaps a few hours or a day. The timing of events is uncertain because
our view of the site was frequently obscured by the fume cloud that
emanates from Pu`u `O`o. Once formed, however, the pits continued to
enlarge for a few weeks, because the cinders don't maintain their integrity
on oversteepened slopes.
These episodic collapses are slowly engulfing the cinder cone.
Although not as dramatic as the collapse of January 1997, when the entire
west flank disappeared overnight, these latest changes will ultimately
carve a notch that breaches the southwest flank of the cinder cone,
exposing the inner crater walls.
In contrast to episodic collapse at the surface is the relentless
subsidence measured by tiltmeters. A tiltmeter on the north flank has
recorded constant tilting inward toward Pu`u `O`o's crater since it was
installed in January 2000. Indeed, the cumulative tilt has dragged the
tiltmeter off scale once already, requiring a tedious repositioning of the
instrument within its shallow borehole.
Total tilt so far is about 850 microradians, which corresponds to
about 25 cm (1 ft) of subsidence of the crater floor relative to the
tiltmeter. We lack sufficient instruments to precisely determine the
center of collapse, but the source is approximated by combining the tilt
data with our ground observations.
These collapse events typically occur without discharge of lava onto
the ground at Pu`u `O`o. Instead the molten stuff slips away in lava
tubes, remaining invisible to our observations until seen at a skylight 1.6
km (1 mi) distant. With it, each day, goes a small part of the cone.
If rocks had no strength, the cracks and pits would change daily.
But the strength of the lava layers beneath the cinders allows the ground
to resist cave-ins and subsidence even as the foundation is plucked and
piped away by magma. The abrupt changes that we describe every few months
may be precipitated by a drop or surge in the magma supply or by
earthquakes, which jostle an already weakened Pu`u `O`o. The constant
subterranean erosion finally exceeds the endurance of rocks at the surface.
Continuous and episodic events characterize many geologic processes.
The Pacific plate drifts northwestward continuously, but the islands grow
in spurts. The building of an active volcanic island continuously loads
the oceanic crust, but earthquakes occur sporadically as the forces
overcome the strength of the rocks. A sea arch may be a tourist attraction
for decades, then, within a week, merely a pile of rubble in the surf zone.
Lava entering the ocean slowly builds a superficially stable bench, but one
night the whole thing slides down the submarine slope, leaving no trace at
the shoreline.
Memorize the skyline presented by Pu`u `O`o today, because it may be
startlingly different in the future.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week. Lava moves away from the vent toward the
ocean in a network of tubes and descends Pulama pali in three separate
areas. A breakout from the tube system above Pulama pali on July 9 fed a
flow streaming down the pali and pooling in the coastal flats. This
activity lasted for two days until the molten lava surface crusted over.
Small surface flows, primarily ooze-outs from inflated areas, are
occasionally observed in the coastal flats. Lava continued to enter the
ocean in the area east of Kupapa`u throughout the week.
There were no earthquakes reported felt during the week ending on
July 12, 2001.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, July 13, 2001 10:00 AM ADT (1800 UTC)
ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
in color code GREEN. All are at or near normal levels of background
seismicity. AVO did not detect ash plumes or significant elevated surface
temperatures in the vicinity of any volcano.
Abbreviated Color Code Key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of Alaska's volcanoes (907) 786-7478
CONTACT INFORMATION:
Tom Murray, Scientist-in-Charge, USGS
tlmurray@usgs.gov (907) 786-7497
Chris Nye, Acting Coordinating Scientist
cnye@giseis.alaska.edu (907) 474-7430
The Alaska Volcano Observatory is a cooperative program of the U.S.
Geological Survey, the University of Alaska Fairbanks Geophysical
Institute, and the Alaska Division of Geological and Geophysical Surveys.
Kamchatkan Volcanic Activity
INFORMATION RELEASE 43-01
Friday, July 13, 2001, 10:58 KDT (21:58 UTC)
The following Release was received by the Alaska Volcano Observatory
via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56(superscript: o) 38'N, 161(superscript: o) 19'E;
Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
Seismic activity was above background levels the past week. The following
seismic episodes were recorded at the volcano: One MI>2 earthquake, many
small earthquakes within the volcano's edifice, 3-minute-long shallow
seismic events, local seismic signals (explosions, avalanches, collapses)
and episodes of weak spasmodic tremor.
According to seismic data, at 09:02 KDT on July 8 (20:02 UTC on July
7), a possible ash-gas explosion occurred, and a series of shallow seismic
events were registered.
According to visual data from Klyuchi (observed by Viktor Ivanov and
Vladmir Demyanchuk), on the night of July 6 explosions were seen to send
ash 600-1000 m above the active dome (3,100 ? 3,500 m ASL, ~11,500 ft.).
Short hot avalanches and pyroclastic flows were also observed. At other
times, clouds obscured the volcano.
KLYUCHEVSKOY VOLCANO; 56(superscript: o) 03'N, 160(superscript: o) 39'E;
Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels. Weak intermittent spasmodic
volcanic tremor was registered. On July 8 tremor amplitudes were up to 0.2
x10(superscript: -6) mps. From 17:31 KDT (4:31 UTC) until 17:50 (4:50
UTC) on July 8 spasmodic tremor amplitudes had increased up to 0.7 x 10
(superscript: -6) mps. On July 9 a gas and steam plume rose 100 m above
the crater. At other times, clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55(superscript: o) 58'N, 160(superscript: o) 36'E;
Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity on July 10-11 was registered under the volcano. At other
times, seismic activity was at background levels. Clouds obscured the
volcano the entire week.
KARYMSKY VOLCANO; 54(superscript: o) 03'N, 159(superscript: o) 27'E;
Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53(superscript: o) 15'N, 158(superscript: o) 50'E;
Elevation 2,751 m.
KORYAKSKY VOLCANO; 53(superscript: o)19'N, 158(superscript: o) 41'E;
Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52(superscript: o) 33'N, 158(superscript: o) 02'E,
Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52(superscript: o) 27'N, 158(superscript: o) 12'E,
Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On July 9-11 both volcanoes were quiet. At other times, clouds obscured the
volcanoes. Seismic activity was at background levels. Weak spasmodic
volcanic tremor was registered.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006
RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
Carolyn Bell
Acting Public Affairs Officer
U.S. Geological Survey
Mail Stop 119 National Center
Reston, VA 20192
Topic 2 of 99 [Geo]: Vulcanism
Response 496 of 997: Marcia (MarciaH) * Fri, Jul 13, 2001 (15:49) * 4 lines
Rob has written a brilliant bit on Caldera Volcanoes for his club in Yahoo:
http://clubs.yahoo.com/clubs/worldvolcanism
It is all I can to to resist the temptation to make it part of Geo lest Yahoo crash and take his magnificent work with them.
Topic 2 of 99 [Geo]: Vulcanism
Response 497 of 997: Marcia (MarciaH) * Mon, Jul 16, 2001 (14:40) * 41 lines
This beats all. *HUGE HUGS, Liam. You are astounding me in the most delightful way. Kilauea!!!
Geologists Explain New Happenings At Kilauea Volcano
In Hawaii, the ground surface subsided abruptly about six weeks ago at Pu`u `O`o, Kilauea Volcano's active cinder-cone vent. Gaping cracks opened around the edges of the subsidence zone, centered on the southwest edge of the cone.
A collapse pit about 30 m (100 ft) in diameter and 15 m (50 ft) deep nibbled into the cone's margin. A second collapse pit continues to deepen within the floor of Pu`u `O`o's crater. One large rock slide and several smaller ones ensued.
Many of these structures likely formed within a short period of time, perhaps a few hours or a day. The timing of events is uncertain because our view of the site was frequently obscured by the fume cloud that emanates from Pu`u `O`o. Once formed, however, the pits continued to enlarge for a few weeks, because the cinders don't maintain their integrity on oversteepened slopes.
These episodic collapses are slowly engulfing the cinder cone. Although not as dramatic as the collapse of January 1997, when the entire west flank disappeared overnight, these latest changes will ultimately carve a notch that breaches the southwest flank of the cinder cone, exposing the inner crater walls.
In contrast to episodic collapse at the surface is the relentless subsidence measured by tiltmeters. A tiltmeter on the north flank has recorded constant tilting inward toward Pu`u `O`o's crater since it was installed in January 2000. Indeed, the cumulative tilt has dragged the tiltmeter off scale once already, requiring a tedious repositioning of the instrument within its shallow borehole.
Total tilt so far is about 850 microradians, which corresponds to about 25 cm (1 ft) of subsidence of the crater floor relative to the tiltmeter. We lack sufficient instruments to precisely determine the center of collapse, but the source is approximated by combining the tilt data with our ground observations.
These collapse events typically occur without discharge of lava onto the ground at Pu`u `O`o. Instead, the molten stuff slips away in lava tubes, remaining invisible to our observations until seen at a skylight 1.6 km (1 mi) distant. With it, each day, goes a small part of the cone.
If rocks had no strength, the cracks and pits would change daily. But the strength of the lava layers beneath the cinders allows the ground to resist cave-ins and subsidence even as the foundation is plucked and piped away by magma.
The abrupt changes that we describe every few months may be precipitated by a drop or surge in the magma supply or by earthquakes, which jostle an already weakened Pu`u `O`o. The constant subterranean erosion finally exceeds the endurance of rocks at the surface.
Continuous and episodic events characterize many geologic processes. The Pacific plate drifts northwestward continuously, but the islands grow in spurts.
The building of an active volcanic island continuously loads the oceanic crust, but earthquakes occur sporadically as the forces overcome the strength of the rocks.
A sea arch may be a tourist attraction for decades, then, within a week, merely a pile of rubble in the surf zone. Lava entering the ocean slowly builds a superficially stable bench, but one night the whole thing slides down the submarine slope, leaving no trace at the shoreline.
Memorize the skyline presented by Pu`u `O`o today, because it may be startlingly different in the future.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u `O`o vent during the past week. Lava moves away from the vent toward the ocean in a network of tubes and descends Pulama pali in three separate areas.
A breakout from the tube system above Pulama pali on July 9 fed a flow streaming down the pali and pooling in the coastal flats. This activity lasted for two days until the molten lava surface crusted over.
Small surface flows, primarily ooze-outs from inflated areas, are occasionally observed in the coastal flats. Lava continued to enter the ocean in the area east of Kupapa`u throughout the week.
There were no earthquakes reported felt during the week ending on July 12, 2001.
Topic 2 of 99 [Geo]: Vulcanism
Response 498 of 997: Marcia (MarciaH) * Wed, Jul 18, 2001 (16:45) * 35 lines
found more goodies from Liam:
Volcano Research Erupts in Space
July 16, 2001
The view from the rim of Mt. St. Helens may be thrilling, but one of the best and safest ways to study volcanoes is from space. New spaceborne instruments let
scientists peer deep into volcanoes and learn about their behavior.
"We now have a view toward the center of Earth," says volcanologist Michael
Abrams of NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Previously, we had to depend on on-site observations not easily accomplished when a volcano was
actively erupting. Now we can safely view them from space and obtain
fast, accurate information from satellites."
Erupting volcanoes cause casualties, destroy property and devastate
local areas. They can also affect regional air quality and visibility with
implications ranging from public health to air traffic control. For example, a
large eruption by the Popocatepetl volcano near Mexico City has serious
consequences for the more than one million people living within 30
kilometers (19 miles) of the volcano.
Now, instruments such as radiometers, spectrometers and
interferometers fly far above Earth's surface year-round. They provide
scientists with continual coverage of the approximately 500 active
volcanoes around the world. The new information they provide makes it
possible to do long-term monitoring, develop new research techniques and
create detailed images and videos, according to JPL researchers.
Data collected over time can be turned into computer animation that
provides dynamic evidence of changes to scientists, government officials
and the interested public. "We are pioneering the use of powerful
commercial animation software to visualize dynamic volcanic processes
such as lava flows, ground deformation, and the appearance and growth of
hot spots," says Dr. Vince Realmuto of JPL's Digital Image Animation
Laboratory.
more... http://www.jpl.nasa.gov/releases/2001/release_2001_147.html
Topic 2 of 99 [Geo]: Vulcanism
Response 499 of 997: Marcia (MarciaH) * Wed, Jul 18, 2001 (19:22) * 23 lines
Mount Etna Erupts; One Man Injured
Reuters
Jul 18 2001 6:39PM
ROME (Reuters) - Sicily's Mount Etna, Europe's most active volcano,
erupted Wednesday, forcing emergency services to build up defenses
against a lava flow moving at 500 feet an hour.
After days of tremors, lava spewed out of a new fissure in the volcano
early on Wednesday at a height of 6,900 feet. Ash and smoke have been
billowing out of Etna and over eastern Sicily for the past five days.
One man needed hospital treatment after he was hit by a rock thrown out
of the volcano.
Emergency services evacuated two restaurants and built up mud walls to
guide the direction of the lava flow, while fire-fighters sprayed the
seething magma with water.
more... http://my.aol.com/news/news_story.psp?type=1&cat=0200&id=0107181840590409
Topic 2 of 99 [Geo]: Vulcanism
Response 500 of 997: Marcia (MarciaH) * Thu, Jul 19, 2001 (13:21) * 51 lines
Kamchatkan Volcanic Activity
INFORMATION RELEASE 44-01
Thursday, July 19, 2001, 12:35 KDT (23:35 UTC on July 18)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS YELLOW.
According to visual data from Kluchi, at 10:33 KDT on 19 July (21:33 UTC on
July 18) an ash plume rose 3000 m above the dome at Sheveluch volcano
(5500 m, 18,000 ft ASL).
At 19:00 KDT (06:00 UTC) on July 14 continuous spasmodic volcanic tremor
increased to 1.7x10-6 mps. At 20:20 KDT (07:20 UTC) on July 14 spasmodic
volcanic tremor amplitudes again increased to 2.0x 10-6 mps and from 3:00
KDT on July 16 (14:00 UTC on July 15) up to 2.5 x10-6 mps. From 23:00 KDT
(10:00 UTC) on July 15 volcanic tremor amplitudes had increased up to 4.0 x
10-6 mps.
According to visual data from Kluchi, at 21:00 KDT (08:00 UTC) on 15 July a
gas and steam plume rose 1500 m above the dome. But, according to seismic
data, the gas and steam plume was probably accompanied by ash explosions.
AVHRR image n12.01196.05:03 (at 18:03 KDT on 15 July) reveals a 3 pixel
thermal anomaly near the SW flank of Sheveluch. Maximum Band 3 temperature
was 44.0 C within a background near 22 C. No associated ash was observed in
AVHRR imagery.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006
RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory4200 University Dr.
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
907-786-7497
Butch Kinerney
U. S. Geological Survey, Office of Communications
bkinerney@usgs.gov
703-648-4732
USGS -- Science for a Changing World
Topic 2 of 99 [Geo]: Vulcanism
Response 501 of 997: Marcia (MarciaH) * Thu, Jul 19, 2001 (21:07) * 3 lines
Kilauea update - remember, one of our main "Fallout Shelters" is a disused lava tube at the summit of Kilauea:
http://hvo.wr.usgs.gov/kilauea/update/main.html
Topic 2 of 99 [Geo]: Vulcanism
Response 502 of 997: Marcia (MarciaH) * Fri, Jul 20, 2001 (00:07) * 3 lines
Rob has a spectacular article on the world's 10 most hazardous volcanoes. I was gonna "borrow" it for Geo, but he worked so hard for it, (been there and done that) so please go read it
http://messages.clubs.yahoo.com/clubs/worldvolcanism/bbs?action=m&tid=worldvolcanism&sid=1600083236&mid=359
Topic 2 of 99 [Geo]: Vulcanism
Response 503 of 997: Rob Glennie (AotearoaKiwi) * Fri, Jul 20, 2001 (04:43) * 7 lines
Hi
Marcia, I don't mind if you do borrow it, just remember as you always do, to put my name beside.
It might be of use to others wanting to know the truth about the volcanoes of the world.
Rob
Topic 2 of 99 [Geo]: Vulcanism
Response 504 of 997: Marcia (MarciaH) * Fri, Jul 20, 2001 (13:41) * 101 lines
Then so I shall - as soon as I post this. Rob writes most excellently and it is more secure for all time on Geo than the somewhat capricious Yahoo. *Hugs* for allowing me to borrow your intellectual property. But, first, this:
Kamchatkan Volcanic Activity - INFORMATION RELEASE 45-01
Friday, July 20, 2001, 12:30 KDT (23:30 UTC)
The following Release was received by the Alaska Volcano Observatory
via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity was above background levels the past week. The
following seismic episodes were recorded at the volcano: Three MI >=2
earthquakes, many small earthquakes within the volcano's edifice,
4-minute-long shallow seismic events, and local seismic signals
(explosions, avalanches, collapses).
At 19:00 KDT (06:00 UTC) on July 14 continuous spasmodic volcanic
tremor increased to 1.7x10-6 mps. Later that day at 20:20 KDT (07:20 UTC)
the tremor amplitudes again increased, to 2.0x 10-6 mps, further increasing
to 2.5 x10-6 mps at 3:00 KDT on July 16 (14:00 UTC on July 15). At 23:00
KDT (10:00 UTC) on July 15 volcanic tremor amplitudes had increased to
4.0x10-6 mps. From then until July 19 volcanic tremor amplitude was, on
average, 4.0x10-6 mps.
Clouds obscured the volcano on July 13 and 14. Observers in Klyuchi
reported that at 21:00 KDT (08:00 UTC) on July 15 a gas and steam plume
rose 1500 m above the dome (4,000 m, 13,200 ft. ASL). According to seismic
data, the gas and steam plume was probably accompanied by ash explosions.
At 13:25 KDT (00:25 UTC) and at 18:10 KDT (05:10 UTC) on July 16 a gas and
steam plume rose 1200 m and 1600 m above the dome (3,700 m, 12,200 ft. ASL
and 4,100 m, 13,500 ft. ASL) and extended to the southwest. At 08:00 KDT on
July 17 (19:00 UTC on July 16) a gas and steam plume, probably accompanied
by ash explosions, rose 1500 m above the dome (4,000 m, 13,200 ft. ASL) and
extended southeast >20 km. At 16:30 KDT (at 03:30 UTC) on July17 a gas and
steam plume, accompanied by ash explosions, rose 3,000 m above the dome
(5,500 m, 18,000 ft. ASL). On July 18-20 gas and steam plumes rose from
between 500 m and 1500 m above the dome (3,000 m, 9,900 ft. ASL - 4,000 m,
13,200 ft. ASL).
AVHRR image n12.01196.05:03 (18:03 KDT on July 15) reveals a 3 pixel
thermal anomaly near the southwest flank of Sheveluch. Maximum Band 3
temperature was 44.0 C within a background near 22 C. No associated ash was
observed in AVHRR imagery.
According to visual data from Klyuchi, at 10:33 KDT on July 19 (21:33
UTC on July 18) an ash plume rose 3,000 m above the dome (5500 m, 18,000 ft
ASL) and extended east. According to the picture by Yuriy V.Demyumchuk, the
source of the explosion was centered on the new dome N 3 (at the northeast
part of the old dome).
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels. On July 13, 14, 17 and 18 weak
intermittent spasmodic volcanic tremor was registered. On July 16-20 gas
and steam plumes rose 50 - 500 m above the crater. On July 18 a gas and
steam plume extended southeast 5 km. At other times, clouds obscured the
volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity on July 14 and 17 was registered under the volcano. At other
times, seismic activity was at background levels. On July 16-20 gas and
steam plumes rose 10 - 500 m above the dome and extended east and southeast
5 km. At other times, clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On July 16-20 both volcanoes were quiet. At other times, clouds obscured
the volcanoes. Seismic activity was at background levels. Weak spasmodic
volcanic tremor was registered.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006
RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
907-786-7497
Butch Kinerney
U. S. Geological Survey, Office of Communications
bkinerney@usgs.gov
703-648-4732
USGS -- Science for a Changing World
Topic 2 of 99 [Geo]: Vulcanism
Response 505 of 997: Marcia (MarciaH) * Fri, Jul 20, 2001 (15:27) * 320 lines
GVP/USGS Weekly Volcanic Activity Report - 11-17 July 2001
http://www.volcano.si.edu/gvp/usgs/
New Activity/Unrest: | Karangetang, Indonesia |
Ongoing Activity: | Etna, Italy | Ijen, Indonesia | Kilauea, USA | Mayon,
Philippines | Merapi, Indonesia | Popocatépetl, México | Semeru, Indonesia
| Shiveluch, Russia | Soufrière Hills, Montserrat | Tungurahua, Ecuador |
Ulawun, Papau New Guinea |
New Activity
KARANGETANG [API SIAU] Siau island, Indonesia 2.78°N, 125.48°E; summit
elev. 1,784 m
After eruptions occurred on 25 and 29 June, volcanic activity continued at
high levels at Karangetang. During 30 June to 8 July seismographs recorded
signals that represented small explosions, avalanches, and an average of 33
multiphase earthquakes per day. During this period a gray plume was emitted
from the volcano, and lava avalanches traveled as far as 2.5 km down the
Keting River and 750 m down the Kahetang River. The volcano is at Alert
Level 3 (on a scale of 1-4).
Background. Karangetang (also known as Api Siau) lies at the northern end
of the island of Siau, N of Sulawesi, and contains five summit craters
strung along a N-S line. One of Indonesia's most active volcanoes,
Karangetang has had more than 40 recorded eruptions since 1675.
Twentieth-century eruptions have included frequent explosions, sometimes
accompanied by pyroclastic flows and lahars.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Karangetang reports
http://www.volcano.si.edu/gvp/volcano/region06/sangihe/karang/var.htm from
the Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
On 13 July the 16th eruptive episode in 2001 took place at the NNE vent of
Etna’s Southeast Crater. During the 4-hour-long episode, lava flows,
Strombolian activity, and several earthquakes occurred. The largest two
earthquakes had magnitudes of 3.9 and were felt 15 km away in the town of
Nicolosi. The Toulouse VAAC reported that a small ash cloud was visible on
the Sistema Poseidon Etna webcam and on satellite imagery. It did not rise
above 3.7 km a.s.l.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Sources: Charles Rivière's web site,
http://perso.club-internet.fr/rivierec/juillet_2001.htm,
Sistema Poseidon http://www.poseidon.nti.it/,
Toulouse VAAC http://www.ssd.noaa.gov/VAAC/OTH/FR/messages.html,
Associated Press http://news.excite.com/news/ap/010713/15/int-italy-etna
Etna Reports
http://www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm from
the monthly Bulletin of the Global Volcanism Network
IJEN eastern Java, Indonesia 8.058°S, 114.242°E; summit elev. 2,386 m; All
times are local (= UTC + 7 hours)
The Darwin VAAC reported that at 0120 on 15 July sulfur fumes entered the
cabin of an aircraft flying from Singapore to Denpasar. At the time,the
aircraft was flying at an altitude of ~2.4 km a.s.l. ~15 km SE of Ijen. VSI
stated that earlier, during 2-8 July, seismic and explosive activity had
increased and the Alert Level had been raised from 1 to 2 (on a scale of
1-4).
Background. The Ijen volcano complex consists of a group of small
stratovolcanoes constructed within the large 20-km-wide Ijen (Kendeng)
caldera. The N caldera wall forms a prominent arcuate ridge, but elsewhere
the caldera rim is buried by post-caldera volcanoes, including Gunung
Merapi stratovolcano, which forms the 2,799 m high point of the Ijen
complex. Immediately W of Gunung Merapi is the renowned historically
active Kawah Ijen volcano, which contains a nearly 1-km-wide,
turquoise-colored, acid crater lake. The picturesque lake is the site of a
labor-intensive sulfur mining operation, in which sulfur-laden baskets are
hand-carried from the crater floor. A half dozen small-to-moderate
phreatic eruptions have taken place from Kawah Ijen during the 20th century.
Sources: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html,
Darwin VAAC http://www.bom.gov.au/info/vaac/advisories.shtml
Ijen Reports
http://www.volcano.si.edu/gvp/volcano/region06/java/ijen/var.htm from the
monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
At Kilauea small surface lava flows traveled along the E and W branches of
the lava flow field active during the last 6 months and moderate amounts of
lava entered the sea at the E Kupapa`u entry. Generally, weak, steady
tremor and related long-period earthquakes continued beneath Kilauea's
caldera. Near Pu`u `O`o, the tremor alternated from weak, to moderate, to
strong over periods of several hours. Elsewhere, seismicity was at normal
levels. Tiltmeters in the summit area and along the east rift zone
indicated no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http://www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
Volcanic activity continued to decrease at Mayon during 816 July, with low
seismicity, occasional SE-directed rockfalls, and a general decrease in SO2
emission rates. Although the volcano’s edifice remained slightly inflated,
a gradual deflationary trend was detected. The activity decrease led
PHIVOLCS to reduce the Alert level from 4 (hazardous eruption imminent) to
3 (increased tendency towards eruption). Authorities removed the
7-km-radius Extended Danger Zone in the SE, but left the 6-km-radius
Permanent Danger Zone in effect on a long-term basis.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Source: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Mayon Reports
http://www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from
the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
During 2-8 July low-pressure emissions from fumaroles rose 700 m above the
volcano. During the same interval lava avalanches traveled SW to a maximum
distance of 2.5 km into the upper reaches of the Sat, Senowo, and Lamat
rivers. The volcano was at Alert Level 2.
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Merapi Reports
http://www.volcano.si.edu/gvp/volcano/region06/java/merapi/var.htm from
the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC 5 hours)
Several small-to-moderate sized emissions occurred at Popocatépetl,
including three on 14 July. According to the Washington VAAC, around 1045
an emission of steam, gas, and small amounts of ash rose to ~7.3 km a.s.l.
and drifted to the W. Emissions also occurred at 2303 and 2341. A cloud
from the latter emission rose to ~6.1 km a.s.l. and drifted to the W.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Sources: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html,
Associated Press
http://dailynews.yahoo.com/h/ap/20010716/wl/mexico_volcano_1.html
Popocatépetl Reports
http://www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html from
the monthly Bulletin of the Global Volcanism Network
SEMERU Java, Indonesia 8.11°N, 112.92°E; summit elev. 3,676 m
Seismic data revealed that during 2-8 July the number of explosions and
avalanche earthquakes at Semeru decreased in comparison to the previous
week. The volcano was at Alert Level 2.
Background. Semeru is the highest volcano on Java and one of its most
active. The symmetical stratovolcano rises abruptly to 3,676 m above
coastal plains to the S and lies at the southern end of a volcanic massif
extending N to the Tengger caldera. Semeru has been in almost continuous
eruption since 1967. Frequent small-to-moderate Vulcanian eruptions have
accompanied intermittent lava dome extrusion, and periodic pyroclastic
flows and lahars have damaged villages below the volcano. A major secondary
lahar on 14 May 1981 caused more than 250 deaths and damaged 16 villages.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Semeru Reports
http://volcano.si.edu/gvp/volcano/region06/java/semeru/var.htm from the
monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
Seismic activity remained above background levels during 6-13 July. Many
small earthquakes were recorded within the volcano’s edifice, along with
weak spasmodic tremor and other local seismic signals, interpreted as
related to explosions, avalanches, and collapses. On 6 July explosions sent
ash to 0.6-1 km above the volcano. In addition, hot avalanches and
pyroclastic flows were observed during clear conditions to be traveling
down the flanks of the volcano. The Concern Color Code <
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm> remained at Yellow.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
During 6 to 13 July volcanic activity at Soufrière Hills remained similar
to the previous week. Lava dome growth appeared to still be concentrated on
the S side of the dome where near-continuous rockfalls occurred. According
to the Washington VAAC, the rockfalls produced ash plumes that did not rise
above 3 km a.s.l. and drifted to the W or WNW. An occasional hot spot was
visible on satellite imagery.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvomrat.com/,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
http://www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
During the week several small-to-moderate eruptions produced ash clouds.
The largest eruption, on 12 July, produced an ash cloud that rose to ~8.3
km a.s.l. and drifted W to NW.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http://www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
ULAWUN New Britain, Papua New Guinea 5.04°S, 151.34°E; summit elev. 2,334 m
A news report on 9 July stated that residents who were evacuated from their
homes near Ulawun were permitted to return home. They were evacuated in May
after the occurrence of relatively high seismic activity and an eruption in
April. On 14 June, almost a month before the news report was published, the
Rabaul Volcano Observatory (RVO) recommended that the Alert Level be
reduced to 1. At this stage of alert people could move back to their homes
with the approval of the local disaster committee, but many residents were
hesitant to return and opted to stay in care centers. After the
aforementioned news article was published some people returned home and RVO
expects more people to return to their villages in the coming weeks.
Background. The symmetrical basaltic-to-andesitic Ulawun stratovolcano is
the highest volcano of the Bismarck arc, and one of Papua New Guinea's most
frequently active. Ulawun rises above the N coast of New Britain opposite
Bamus volcano. The upper 1,000 m of the 2,334-m-high volcano is
unvegetated. A steep-walled valley cuts the NW side of the volcano, and a
flank lava-flow complex lies to the S of this valley. Historical eruptions
date back to the beginning of the 18th century. Twentieth-century
eruptions were mildly explosive until 1967, but after 1970 several larger
eruptions produced lava flows and basaltic pyroclastic flows, greatly
modifying the summit crater.
Sources: Rabaul Volcano Observatory
The National http://www.zipworld.com.au/~national/0709/nationfrm13.htm
Ulawun Reports
http://www.volcano.si.edu/gvp/volcano/region05/new_brit/ulawun/var.htm from
the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Topic 2 of 99 [Geo]: Vulcanism
Response 506 of 997: Marcia (MarciaH) * Fri, Jul 20, 2001 (15:33) * 113 lines
Etna - photos, activity update
*****************
Etna photos
*****************
From: tom pfeiffer
Dear volcanophiles,
this is to announce that a large number of new photos of Etna volcano's
recent activity have been made available on 6 separate pages on Tom
Pfeiffer's website at
http://www.geo.aau.dk/palstrat/tom/santorini_homepage/bilder/photo_gallery.htm
These include documentation of the constant effusive activity present during
May, 5 paroxysms of the SE crater from 17-27 June, and a spectacular tornado
observed on Etna's summit during the eruption of 22 June.
Kind regards
Tom Pfeiffer
Email: pfeiffer@geo.aau.dk, tpfeif@hotmail.com
*****************
Etna activity
*****************
From: Dan Shackelford
New Paroxysm at Etna and Strong Earthquakes Too.
Since about 13 July (not sure exact date, my French is kind of rusty in
reading this website) there has been strong seismicity at Etna. Epicenters
of the 15 July earthquakes (to M3.2) near Valle del Bove. Following four
days of quiet, another paroxysm from South East Crater between 0230 - 0430
on 17 July. Strong fountaining from the vent Sudestino on the NNE flank of
the S.E.C. and lava flowage. Strong quake at 0730 opens a 360m long fissure
from Sudestino and downflank, and a 200m long Curtain of Fire plays along
this fissure, with copious lava outpourings, somewhat remenescent of the
1989 fissure activity. Fountaining is to 40m in height. Around 2300 on the
17th, a second fissure opened as well. (If someone reads French better than
I, you might be able to read the website below and correct some of my
errors in this brief report).
Loosely translated from
http://perso.club-internet.fr/rivierec/juillet_2001.htm
Setting up to date of 17 July 2001 (23h00) evening Nunzio Di Salvo inform
me that a new fracture have just opened approximately 200 meters under the
refuge of Torre del Filosofo in direction of Valle del Bove. This fracture
is in the direction of Montagnola at the edge of the access road to the
refuge.
Setting up to date of 17 July 2001 (21h30) : Visit in end according to
midday of Antonio Nicoloso and two guides of Southern Etna on the new
fracture with the foot of Sudestino at the base of the crater South Is ,
the flow of lava is finished on the fracture, the lava is consolidating
itself. On the other hand below the fracture the lava continues to advance
in the plain of ash towards valle LED bove over a width of 200 meters, this
seems to mean that the lava uses where several tunnels to leave low. The
face of lava this evening A crosses the View-point to move towards Valle
del Bove. On the Northern fracture the flows of lava are finished.
Setting up to date of 17 July 2001 (18h00) :
NEW PAROXYSM OF CRATER CUS EST+EARTHQUAKES
This night, after a lull of four days, the crater South-east is again
entered an eruptive phase between 02H30 and 04h30 (standard time). It is
the 17eme paroxysm of the year 2001. A group of four people was with the
refuge of TDF. From 00h15 the lava emerges from the Northern fracture and
of the mouth of the Southern crater Is According to the first observations
the explosive activity followed closely the emission of casting. The magma
goes up inside the cone to its edge and successively from the gas bubbles
come to explode and project scraps of lava on the sides of the crater. Per
moments of the gas bubbles larger than the cone are emitted and illuminate
the whole of the craters.
On the Northern fracture, the crater "Levantino" is animated by a
beautiful effusive and explosive activity, with fountains of lava. The
direction taken by castings does not have varié; they move towards the
East and North. The flow of lava flow is very significant. With 04h30
(standard time) the activity ends in emissions of ashes with South Is .
2nd part With 07h30 (standard time) an earth tremor occurs which is felt in
the zone of Sapienza. At the same time a fracture with the foot of the
crater opens South Is it leaves the crater Sudestino with the altitude of
3081m in direction of the South. Its length is 360 meters
At the altitude of 3034m the fracture releases from the fountain of lava of
a score of meters height over a 200 meters length, the lava runs out in
direction of the View-point. The speed of the lava is fast, it exceeds the
5 m/s. The activity of does not decrease, it increases even per moments,
and gives fountains a height of 40m. the whole of these observations are
not without pointing out the fissurale activity of 1989
Luigi Lanzafame I.n.g.v, which is with me at the edge of the fracture,
informs me of the evolution of the seismic activity during these last days
and announces me that in the morning a jolt reached once again 3.9 on the
scale of Richter. It informs me about the progression of the fractures
which continue in particular to widen that which passes to the West of
Montagnola and which moves towards Sapienza.
Observations make by Charles Rivière, Luigi Lanzafame I.n.g.v, Robin
Campion with his/her father L.a.v.e (Belgium) and Marc Caillet (Company of
Volcanology of Geneva)
Setting up to date of 16 July 2001: Today it is not the ordinance of
the prefecture which prevented the access at the edge of the View-point of
Valle del Bove but nature it even. Yesterday evening, of the new earth
tremors were recorded. The magnitude of the earthquake in the zone of the
fracture of 1989 is 3.2 on the scale of Richter with the epicentre located
towards Valle del Bove.
Topic 2 of 99 [Geo]: Vulcanism
Response 507 of 997: Marcia (MarciaH) * Fri, Jul 20, 2001 (21:52) * 30 lines
Mt Etna Webcam has moved url
http://web.poseidon.nti.it/Sorvis/Default.htm
or http://web.poseidon.nti.it/Sorvis/vulcano.asp?Vulcano=Etna&Reflesh=30
Italian Towns Set to Evacuate As Etna Erupts
CATANIA, Sicily (Reuters) - Sicily's Mount Etna, Europe's most active volcano, continued to spew lava on Friday,
prompting authorities to warn people in nearby towns of the possibility of evacuation.
"It is a real eruption, we are worried," said Alfredo di Pace, prefect of Catania, which sits at the base of the volcano.
About 15,000 people live in the towns of Nicolosi, Pedara and Ragalna, nestled on the southern slope of the volcano and
Di Pace told reporters that residents in all three had been warned of the possibility of evacuation.
The head of Italy's civil protection agency Franco Barberi said on Thursday the area would be declared a state of
emergency to allow authorities on the island to get army back-up or extra funds quickly if the situation gets worse.
Emergency authorities are building up mud walls to guide the lava flow safely and have sprayed the boiling magma with
water.
There are still five miles between the crest of the lava and Nicolosi. Officials said there was no danger yet because the lava
had slowed down considerably once the magma hit less steep ground.
"There is no real threat for now," said Salvatore Moschetto, mayor of Nicolosi, who has been monitoring the situation with
civil protection officials for days.
But the lava has already damaged chairlifts dotted up the volcano, which also acts as a popular skiing resort. Tourism
representatives have said the magma is so hot that it is unlikely any snow will be able to settle once the winter comes.
Etna has been billowing smoke and ash over eastern Sicily since late last week and on Wednesday a new fissure cracked
open at a height of 7,000 feet, sending a lava flow crawling down the volcano's southern slope.
The stream of fiery-orange magma is being reinforced from another new fissure higher up the mountain at 2,400 meters.
Catania's Institute of Vulcanology said the 250-meter wide flow had dropped to a height of 1,300 meters and was edging
forward at about 10 to 20 yards per hour.
Hundreds of people have headed to Etna to watch the eruption but Di Pace urged them to stay away from the streams of
lava.
The last time Etna posed a threat was in 1992 when lava streams headed toward Zafferana, a town of 7,000 people
crouched on Etna's lower slopes. The Italian military had to use controlled explosions to divert the flow.
Topic 2 of 99 [Geo]: Vulcanism
Response 508 of 997: Marcia (MarciaH) * Tue, Jul 24, 2001 (14:57) * 120 lines
*****************************************************
AGU Session -- Ten Years of Science from the 1991
Mount Pinatubo Volcano Eruption
*****************************************************
From: Alan Robock
I would like to announce the approval of a Union Session at the Fall AGU
meeting to celebrate the 10th anniversary of the Pinatubo Eruption. The
Fall Meeting will be December 10-14, 2001, and the deadline for
electronic abstracts is September 6, 1400 UT. We look forward to
your contributed talks. The session description is below.
Alan Robock
TEN YEARS OF SCIENCE FROM THE 1991 MOUNT PINATUBO VOLCANO ERUPTION
The 1991 eruption of Pinatubo Volcano in the Philippines was one of the
largest volcanic eruptions of the 20th Century and spawned research in
many disciplines. For example, in the 10 years since the eruption,
volcanologists and seismologists have substantially improved
understanding of how magma ascent, magma mixing, and groundwater
produced the distinctive patterns of seismicity, gas flux, and strain
that foretold of Pinatubo's eruption. Atmospheric scientists discovered
that winter warming (a forced positive mode of the Arctic Oscillation)
follows large, sulfate-rich tropical explosive eruptions and quantified
the effects of volcanic aerosols on ozone depletion. Fluvial
hydrologists found world-record sediment yields and are discovering both
controls and key indicators of watershed recovery after such a massive
disturbance. On its tenth anniversary, we invite papers that emphasize
new insights arising from the Pinatubo eruption and its aftermath, in
volcanology, volcano-seismology, volcano geodesy, geochemistry, remote
sensing, fluvial and watershed processes, plume transport, effects on
ozone, radiative forcing, and climate response.
Convenors:
Alan Robock, Department of Environmental Sciences,Rutgers University,14
College Farm Road,New Brunswick,NJ
08901-8551,Phone:732-932-9478,Fax:732-932-8644, E-mail:
robock@envsci.rutgers.edu
Christopher Newhall,USGS,Univ. of Washington,Dept Geological Sciences,Box
351310,Seattle,WA 98195,Phone:206-553-6986,Fax:206-543-3836,E-mail:
cnewhall@geophys.washington.edu
John Power,USGS-Alaska Volcano Observatory,4200 University Dr.,Anchorage,AK
99508,Phone:907-786-7426,Fax:907-786-7425, E-mail: jpower@usgs.gov
*****************************************************
AGU Session -- Advances in Modeling Flow Processes:
Volcanoes, Floods, Impacts and Mass movements
*****************************************************
From: tgregg@nsm.buffalo.edu (Tracy K.P. Gregg)
We are pleased to announce the formation of a special session at Fall AGU.
The description follows, and we welcome any contributions regarding
volcanological fluid dynamics. Please contact Mark Bulmer
(mbulmer@nsm.si.edu) or Tracy Gregg (tgregg@nsm.buffalo.edu) if you have
any questions.
P11 Advances in Modeling Flow Processes: Volcanoes, Floods, Impacts
and Mass movements (Joint with H, T, V)
Data collected from Mars, Venus and the Gallilean satellites in the
past decade have provided researchers with an unprecedented ability
to quantify the morphologies on these planetary bodies. For example,
there is better global topographic coverage of Venus than there is on
Earth, and by the time Mars Global Surveyor (MGS) has finished its
extended mission(s), the global topography of Mars will be better
constrained than it is on Venus. Advances in terrestrial Global
Positioning Systems (GPS) has simultaneously allowed for increasingly
detailed (centimeter-scale) topographic investigations of terrestrial
landforms, thereby enabling scientists to quantitatively compare
landforms on all the solid bodies of the solar system. These new
data sets have proved particularly useful for examining the dynamics
of material transport. All of these processes involve the transport
of material (liquid, solid, gas, or some mixture of any or all
three), and require detailed topographic data to help untangle their
complexities. This session will bring together researchers
quantitatively investigating volcanic flows (such as lava and
pyroclastic deposits), floods, impact crater ejecta, and mass wasting
deposits (such as debris flows and landslides) to examine new
advances in modeling.
Conveners: Dr. Mark Bulmer, CEPS, National Air and Space Museum,
Smithsonian Institution, Washington DC, Tel:(202) 633-9896; E-mail:
mbulmer@nasm.si.edu; Dr. Tracy K.P. Gregg, Dept. of Geology,
University at Buffalo, Buffalo, NY 14260, Tel:(716) 645-6800 x2463;
E-mail: tgregg@nsm.buffalo.edu.
**********************************************
AGU Session -- Experimental volcanology:
Sturtevant Memorial Session
**********************************************
From: Emily Brodsky
Fall 2001 AGU Special Session
Experimental volcanology: Sturtevant Memorial Session
Co-convenors: E. Brodsky, D. Dingwell, M. Ichihara, H. Mader
Volcanic eruptions are one of the clearest expressions of the continuing
evolution of planet Earth. Yet our understanding of the forces controlling
the timing, extent, magnitude and frequency of volcanic eruptions is poor.
Understanding explosive eruptions is especially difficult due to their
relative rarity and inaccessibility in the field. Here, an experimental
approach is of great and growing importance. We invite scientists from the
diverse branches of the earth sciences related to volcanic eruptions to
contribute to a broad discussion of the issues, challenges, developments,
and accomplishments of recent experimental volcanology. We welcome
presentations of laboratory experiments focussed on any aspect of eruption
dynamics including degassing, vesiculation, fragmentation, pyroclastic flow
generation and emplacement, lava flow, dome-building, plume formation,
magma chamber convection and volcanic tremor.
Brad Sturtevant was a pioneer in the development of
experiments for the understanding of volcanic eruptions.
This session is in honor of his clarity of thought,
ingenuity of design and objectivity of analysis.
Topic 2 of 99 [Geo]: Vulcanism
Response 509 of 997: Marcia (MarciaH) * Tue, Jul 24, 2001 (14:58) * 54 lines
*****************************************
MVO Weekly Activity Report, 20 July 2001
*****************************************
From: Peter Dunkley
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 13 July 2001 to midday, 20 July 2001
Activity at the Soufrière Hills Volcano has increased compared with
previous weeks. The seismograph network recorded 719 rockfall signals,
57 long period events, 25 long period rockfalls, 5 hybrid events and 2
volcanotectonic earthquakes. Although an increased number of rockfalls
were registered during the course of the week, most of these were very
small events.
Clear views of the upper parts of the volcano were not seen, because of
low cloud and ash-venting. Growth of the dome continues on the southern
side above White River, where observation flights indicate
near-continuous rockfall activity. During the course of the week,
numerous small pyroclastic flows originated from the southern flank of
the dome and flowed eastwards down the Tar River valley. Most of these
followed a path along the southern side of the valley, where it abuts
against the base of Perches Mountain, and a few reached as far as the
Tar River delta. Several small pyroclastic flows also originated on the
western side of the dome and flowed for short distances into the upper
part of the Gages area.
Sulphur dioxide fluxes of 943 and 709 tonnes per day were measured on 17
and 19 of July respectively.
The daytime entry zone (DETZ) remains closed until further notice.
Activity could increase quite suddenly, with a dangerous situation
developing very quickly. Ash masks should be worn in ashy conditions.
The Belham Valley should be avoided during and after heavy rainfall due
to the possibility of mudflow activity.
Residents of Montserrat and visitors to the island are advised to tune
into ZJB Radio for up-to-date information on the volcano. Access to
Plymouth, Bramble airport and beyond is prohibited. There is a maritime
exclusion zone around the southern part of the island that extends two
miles beyond the coastline from Trant's Bay in the east to Garibaldi
Hill on the west coast.
12 noon, Friday, 20 July 2001
Peter Dunkley
Montserrat Volcano Observatory
Mongo Hill
Montserrat
West Indies
Topic 2 of 99 [Geo]: Vulcanism
Response 510 of 997: Marcia (MarciaH) * Tue, Jul 24, 2001 (16:01) * 34 lines
From Liam....with great thanks,
Tiny crystals predict huge volcano in western U.S.
(posted 07/20/01)
by Terry Devitt
Reading the geochemical fine print found
in tiny crystals of the minerals zircon and
quartz, scientists are forming a new
picture of the life history - and a geologic
timetable - of a type of volcano in the
western United States capable of
dramatically altering climate sometime
within the next 100,000 years.
With insight gained from new analytical
techniques to study crystals of zircon and
quartz, minerals that serve as veritable
time capsules of geologic events, a group
of scientists from UW-Madison has
proposed a new model for the origin of
volcanism in young calderas.
These are volcanoes that occur over "hot
spots" in the Earth and they erupt every
few hundred thousand years in
catastrophic explosions, sending
hundreds to thousands of cubic
kilometers of ash into the atmosphere
and wreaking climatic havoc on a global
scale.
more story, graphics and other goodies: http://www.news.wisc.edu/view.html?id=6326
Topic 2 of 99 [Geo]: Vulcanism
Response 511 of 997: Marcia (MarciaH) * Tue, Jul 24, 2001 (20:00) * 38 lines
****************************************
Satellite Images - Etna, Mayon, Kilauea
****************************************
From: Claude Desgroseilliers
Ash Plume from Mt. Etna
http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=5033
The Continuing Eruption of Mt. Etna
http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=5032
Mayon volcano, southeast Luzon, Philippines
http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=5024
Lava Tubes on Mt. Kilauea
http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=5025
Salutations, Regards
Claude Desgroseilliers
************************
Mud volcanoes?
************************
From: Elmar Bartlmae
Mud Volcanos
I am a TV producer and I am trying to locate film or video material of an
erupting mud volcano. I heard they produce tall gas flames, and most such
eruptions have been seen near Baku in Azerbaijan.
Has anyone witnessed such an eruption and can tell me more about other
locations and how they look like?
Thank you in advance.
Elmar Bartlmae
elmar.bartlmae@weltderwunder.de
Elmar Bartlmae
Producer
Topic 2 of 99 [Geo]: Vulcanism
Response 512 of 997: Marcia (MarciaH) * Tue, Jul 24, 2001 (20:09) * 90 lines
The State of New Zealand's Volcanoes:
SCIENCE ALERT BULLETIN: Tongariro V01/01
0900h 20 July 2001 (Friday)
Earthquake activity, Mt Tongariro
Small volcanic earthquakes have been recorded beneath Mt Tongariro since February 2001. These
by themselves do not give reason to change the Alert Level. The Alert Level for Tongariro remains at
level 0.
As part of our routine monitoring of seismic activity, we have recorded several volcanic earthquakes
per month at Mt Tongariro since at least February. These earthquakes are very small and have only
been well recorded by one seismometer in our permanent network. Without data from at least three
seismometers it is not possible to locate the exact source of these volcanic earthquakes.
To better understand the significance of these earthquakes we have:
? deployed portable seismic recorders on Mt Tongariro
? reviewed other available seismic data
? conducted sampling of selected hot springs, crater lakes and fumaroles in the area.
The review of seismic data has shown that these small volcanic earthquakes have been present since
at least February 2001, while the analysis of data from a portable array operated by Cambridge
University (January-May) has allowed us to locate one of these events near the Te Maari craters.
Results available to date from water and gas sampling show no changes in the chemistry of the
springs or fumaroles.
Mt Tongariro is a volcano complex that lies to the north of Ngauruhoe. It consists of numerous craters
and vents. Te Maari craters lie about two kilometres east of Ketetahi hot springs on the north side of
Mt Tongariro. The Te Maari craters are the last craters to be active on Tongariro. Small ash eruptions
were recorded from these craters in 1869 (accompanied by a violent earthquake), June 1886,
November 1892 and November-December 1896.
At this time we have no reason to believe that an eruption will occur at Te Maari in the near future.
However we will continue to monitor the situation.. Based on the data available to date there are no
reasons significant enough to change the Alert Level. The Alert level for Tongariro remains at level 0.
Brad Scott
Duty Volcanologist
http://www.gns.cri.nz/earthact/volcanoes
posted by jeff lyall 10:05 AM
4/17/2001
January 26 eruption at Kuirau Park, Rotorua
Notes and comments from BJ Scott.
These notes and comments are based on a visit on Friday evening, and again on Monday.
On Friday 26 January about 3.30 to 3.40 PM NZDT, a muddy hot pool 2.5-3m diameter (Spring 721)
burst into eruption, generating the largest hydrothermal eruption in Kuirau Park since 1966. The
eruption of blocks and mud was to about 100 metres height and produced a thick carpet of blocks
and mud to the east, extending over 120m from the vent. The eruption was very directional. Very little
ejecta is distributed to the west (may be less than 30m from the vent). Blocks up to about 1m diameter
were projected over 50m from vent, while blocks around 0.1m or less diameter landed over 100m
away. The crater formed is about 10-12m in diameter.
It was possible to recognise 4 eruption deposits on Friday evening, and this may give some insight
into the eruption. These are;
1) A ballistic block bed, the most widely distributed unit. It would appear that this unit is almost entirely
formed from Oranui Formation.
2) A basal dark grey mud deposit directed to the east, ranging from about 400mm thick to a trace of
only mm at Ranolf Street.
3) An upper, smaller and slightly lighter grey muds deposit. This was also distributed to the east,
overlying the basal darker mud. It was smaller in distribution and the dispersal access was a little
more to the SE. Thickness appeared to be about 100-150mm at it’s thickest.
4) A dark grey, very liquid hydrothermal mud distributed to the west, onto the adjacent road. This
appears to be the contents of Spring 721.
The ballistic blocks appear to be present through almost all of the deposit. That is there are blocks
that are clearly on top of all the mud’s, while other blocks are coated by mud with shelter zones on
their leeward sides. Based on first impressions the dark grey liquid mud’s where erupted first, to the
west. Then the main phase of the eruption commenced, ejecting mud’s and ballistic blocks to the
east, this was followed by a smaller mud rich phase (no relationship with ballistics was ascertained),
which was followed by a distinct ballistic shower, numerous cm sized blocks are impacted into all the
mud’s. The ballistics extend well beyond the mud’s to the NE and its is not clear from first impressions
the exact relationship to the mud’s.
Fallout of the mud layers has loaded all the trees and shrubs within the ejecta apron, bending and
breaking many.
posted by jeff lyall 11:47 AM
http://www.gns.cri.nz/earthact/volcanoes/bulletins/blogger.html
Topic 2 of 99 [Geo]: Vulcanism
Response 513 of 997: Marcia (MarciaH) * Tue, Jul 24, 2001 (23:11) * 18 lines
Sleuth Liam strikes again. This one is amazing!
*************************************************
Was Tunguska really a voilent volcanic eruption?
*************************************************
Physicist Kundt claims geologists guilty of talking bolides July 23, 2001
Wolfgang Kundt, a German physicist, has claimed that the Tunguska event of 1908, widely assumed to have been caused by an exploding bolide, was really a violent volcanic eruption and blames geologists for the misinterpretation
[]The eruption over the Tunguska plateau one summer morning 93 years ago scorched and flattened nearly 1000sq miles of forest (picture). For much of the intervening time, since expeditions were despatched to the area many years afterwards, prevailing scientific opinion has held that the event was due to the detonation, in the atmosphere, of an incoming meteorite.
However, Wolfgang Kundt, Professor of Astrophysics at the University of Bonn, has other ideas. Writing in August s issue of the journal Current Science, he cites 17 factors that he believes suggest otherwise - including the patterns of geological faults and fallen trees. Kundt thinks the event was the result of gigantic volcanic outgassing involving ten million tonnes of natural gases escaping through a Kimberlite Pipe the structures that contain diamonds in South Africa, notably near Kimberley, after which they are named.
Kundt told The Times: "If they find that, as is indicated, it would turn Siberia into a rich industrial country", dismissing the comet and meteorite theories as pseudo-science. "If good physicists had been involved from the start this problem would never have occurred" he said. "As it was [the early study of the Tunguska phenomenon] was left to geophysicists and geologists with no knowledge of extraterrestial bodies."
Two recent expeditions from the University of Bologna claim to have found microscopic traces of dust with extraterrestrial signatures in spruce resin, lending support to the traditional view that the incoming bolide was a stony meteorite c. 70 metres wide. Approaching at a 45-degree angle, it exploded four miles above the surface. However, such a meteorite cannot account for the Kimberlite-like conical holes (12 in all) that according to Kundt occur near the known epicentre
Topic 2 of 99 [Geo]: Vulcanism
Response 514 of 997: Rob Glennie (AotearoaKiwi) * Wed, Jul 25, 2001 (04:09) * 5 lines
Hi all
Etna volcano continues to erupt lava and ash for a third straight day and now TVNZ is reporting the eruption as well as the Press newspaper. I am surprised by the size of this eruption - it is obviously going on longer than many anticipated. It is with great interest I watch the eruption as the last one I can remember lasting this long was the 1992 event where lava got too close for the comfort of Zafferana.
Rob
Topic 2 of 99 [Geo]: Vulcanism
Response 515 of 997: Marcia (MarciaH) * Wed, Jul 25, 2001 (13:27) * 0 lines
Topic 2 of 99 [Geo]: Vulcanism
Response 516 of 997: Marcia (MarciaH) * Wed, Jul 25, 2001 (13:32) * 4 lines
Recent screen captures from http://web.poseidon.nti.it/Sorvis/vulcano.asp?Vulcano=Etna&Reflesh=30
Topic 2 of 99 [Geo]: Vulcanism
Response 517 of 997: Marcia (MarciaH) * Wed, Jul 25, 2001 (22:57) * 84 lines
Weekly Report No. 623 2-8 July, 2001
Weekly Report No. 623
2-8 July, 2001
Karangetang
Siau island; 2°47' N, 125°29' E
After 25 and 29 June, 2001 eruptions, both from visual and instrumental
monitoring Karangetang still show a high activity which seems from both
visual and instrumental monitoring. Seismograph which operated again since
30 June, recorded amount of seismicity such as small explosion, avalanche
and multiphase earthquakes, with an average of each is about 33 a day.
Visual activity marked with white - grey of plume emission, lava avalanche
and lava flow. Lava avalanche traveled to the Keting river as far as 2500
m, and 750 m to the Kahetang river. The other seismicity is uncontinuous
volcanic tremor which have 1-12 mm of amplitude. Complete seismicity listed
as follow: deep volcanic (A) 11 events, tectonic 10 events, multiphase 287
events, avalanche 237 events, and 233 events of small explosion.
Karangetang volcano is in level 3.
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Visual activity which seems from Merapi summit were 700 m height of white
thin color of solfatara emission. The emission was in low pressure. Lava
avalanche were ongoing and toward to the upstream of Sat, Senowo, and Lamat
rivers with the distance of 2.5 km. Seismicity dominated with avalanche
earthquakes.
Merapi volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
No major changing has shown from Lokon activity from visual observations,
but instrumental monitoring showed an increasing activity which represents
from the high of shallow volcanic earthquakes during the report. The
observer from Kakaskasen observatory noticed 25-200 m height of white
thin-medium gas emission which appears from Tompaluan crater. Seismicity
records during the week were: 5 events of deep volcanic (A), 11 events of
shallow volcanic (B) and 33 events of tectonic earthquake and uncontinuous
tremor volcanic.
Lokon volcano is in level 2.
Ijen
East Java;8°3.5' S, 114°14.5' E
Ijen shows again an increasing activity, and since the reporting time, Ijen
activity removed from level 1 to the level 2. That was marked with
appearance of tremor volcanic earthquake with amplitude of 0.5-3 mm. Others
seismicity listed below: 1 event of deep volcanic (VA), 6 events of shallow
volcanic (VB), 1 event of small explosion and 3 events of tectonic
earthquake.
Ijen volcano is in level 2.
Semeru
East Java; 8°6.50' S, 112°55' E
Visual observation could not be done well because the weather was cloudy
surround the summit. But from seismicity, Semeru activity looks decrease,
which represent from the decreasing number of explosion and avalanche
earthquake. Complete data were: 299 events of explosion earthquake, 30
events of avalanche, and 6 events tectonic earthquake.
Semeru volcano is in level 2.
Anak Krakatau
Sunda Straits, 6°6'5.8" S, 105°25'22.3" E
No major changing in Krakatau activity, both from visual and instrumental
monitoring. Seismic record within the period listed below: 18 event of deep
volcanic (A), 285 events of shallow volcanic (B) and 4 events of tectonic
earthquake.
Anak Krakatau is stated in level 2.
G. Soputan
North Sulawesi,124º41'12"N, 1º6'20"E
Observer noticed 75 m of white thin-medium gas emission above the summit.
But seismicity recorded 2 events of deep volcanic (VA), 34 events of
tectonic and 123 events of avalanche earthquakes.
Soputan is stated in level 2.
G. Kerinci
West Sumatera
Kerinci seems more stable in activity, although during the time shows
decreasing in number of earthquakes. Seismicity dominated with small
explosion and tectonic earthquakes. Detail seismicity were: 360 events of
small explosion and 10 events of tectonic earthquake.
Kerinci volcano is in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 518 of 997: Marcia (MarciaH) * Wed, Jul 25, 2001 (23:06) * 338 lines
GVP/USGS Weekly Volcanic Activity Report 18-24 July 2001
http://www.volcano.si.edu/gvp/usgs/
New Activity/Unrest: | Etna, Italy | Shiveluch, Russia |
Ongoing Activity: | Karangetang, Indonesia | Kilauea, USA | Krakatau,
Indonesia | Mayon, Philippines | Merapi, Indonesia | Popocatépetl, México |
Semeru, Indonesia | Soufrière Hills, Montserrat | Tungurahua, Ecuador |
New Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m: All times are
local (= UTC + 2 hours)
A large flank eruption began on 17 July at Etna and produced several lava
flows that were emitted from four new fissures and strong explosive
activity at a fifth. Four of the fissures were on the SE flank, and the
fifth was on the NE flank. There were fears that lava flows from two of the
fissures would reach the town of Nicolosi (~15 km SSE of the volcano) and a
nearby popular tourist area. According to the Italy’s Volcanoes website,
the 17th eruptive episode in 2001 began on the morning of 17 July and a few
hours later a new eruptive fissure opened at the S base of the Southeast
Crater cone (see map of fissure locations
http://volcano.si.edu/gvp/usgs/maps.htm#etna_map). Mild Strombolian
activity occurred from the fissure and a lava flow extended SSE. During the
evening of the 17th a second eruptive fissure emitted an extensive lava
flow that spread SE toward the Valle del Bove rim. On 18 July at about 0200
a seismic swarm was accompanied by the opening of a third eruptive fissure
at about 2,100 m elevation. Mild Strombolian activity and a sluggish lava
flow traveled toward the S. Later in the day the lava flow crossed the main
access road to the S flank of Etna and headed towards Nicolosi. A spectator
was seriously injured when he fell while trying to avoid projectiles.
On the evening of 18 July the fourth eruptive vent since the episode began
opened near 2,700 m elevation on the SE flank. The main explosive activity
occurred at this vent, including powerful Strombolian blasts that sent
incandescent volcanic bombs as high as 200 m and produced ash columns that
rose several kilometers. Lava from this vent progressed towards the tourist
complex around the Rifugio Sapienza. On 20 July around 1100 a fifth
eruptive fissure became active, but unlike the other fissures it was on the
NE flank in the Valle de Leone. Lava emitted from this fissure flowed SE.
By 22 July the lava flow from the third fissure was 4 km away from
Nicolosi, but it was advancing very slowly over nearly flat terrain and
appeared to have stopped by the next day. Earth barriers were created in an
attempt to divert lava from the tourist complex that had already been
damaged by volcanic bombs. Continuous ashfall occurred near the explosive
fourth vent. The entire area between the towns of Giarre (~17 km E of the
volcano) and Catania (~25 km SSE of the volcano) was covered by a thin
layer of ash; there was an especially large amount of ash in Catania. The
Fontanarossa International Airport of Catania was closed on 22 July and
again the next day due to ashfall.
The Toulouse VAAC reported that the new Etna Sistema Poseidon webcam
http://web.poseidon.nti.it/Sorvis/Default.htm showed ash emission
starting on 20 July. The previous webcam had been damaged by earthquakes
near the start of the eruption. SE-drifting ash clouds were detected
several times on satellite imagery. An ash cloud was reported to have
reached a maximum height of ~5.2 km on 22 July. According to news reports,
a state of emergency was declared for the area near Etna on 20 July. As of
24 July the eruption was continuing.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Map of fissure and lava flow locations
http://volcano.si.edu/gvp/usgs/maps.htm#etna_map,
Video of ABC News report
http://mediaframe.yahoo.com/launch?&p=news&l=SAM&a=0,15&.cobrand=abc&f=37574
568&lid=rnv-56-s.1268802,rnv-100-s.1268802,rnv-300-s.1268802&lid=rnv-56-s.15
82299,rnv-128-s.1582299,rnv-200-s.1582299,rnv-300-s.1582299&bw=http://dailyn
ews.yahoo.com/h/a/g/abc/%3Fu&.test=0&t=Volcano%20Threatens%20Sicilian%20Town
Sources: Italy’s Volcanoes , http://www.geo.mtu.edu/~boris/ETNA_news.html,
Charles Rivière’s web site
http://perso.club-internet.fr/rivierec/juillet_2001.htm,
Sistema Poseidon, http://www.poseidon.nti.it/,
Toulouse VAAC http://www.ssd.noaa.gov/VAAC/OTH/FR/messages.html,
NASA
http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=5033,
Reuters http://news.excite.com/news/r/010719/17/science-italy-volcano-dc,
Associated Press http://news.excite.com/news/ap/010723/10/italy-etna,
CNN http://www.cnn.com/2001/WORLD/europe/07/21/etna.lava/index.html
Etna Reports
http://www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m; All times are local (= UTC + 12 hours)
A moderate-sized eruption at Shiveluch on 19 July prompted KVERT to raise
the Concern Color Code
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm from Yellow to
Orange the same day. The eruption occurred at 1033 and produced an ash
plume that rose 3 km above the lava dome. Prior to the eruption, during 14
through 16 July, spasmodic volcanic tremor increased several times. On 15
July at 1803 a three-pixel thermal anomaly was visible on AVHRR satellite
imagery near the SW flank of the volcano. Also, at 2100 a gas-and-steam
plume was observed rising 1.5 km above the dome.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
KARANGETANG [API SIAU] Siau island, Indonesia 2.78°N, 125.48°E; summit
elev. 1,784 m
During 9-15 July volcanic activity was at a level similar to the previous
week. Seismicity was dominated by 572 small explosions, 451 multiphase
earthquakes, and continuous lava avalanches. The avalanches traveled up to
2.5 km down the Keting River and lava flowed as far as 750 m down the
Kahetang River. In addition, a gray plume was emitted from the volcano,
which remained at Alert Level 3 (on a scale of 1-4).
Background. Karangetang (also known as Api Siau) lies at the northern end
of the island of Siau, N of Sulawesi, and contains five summit craters
strung along a N-S line. One of Indonesia's most active volcanoes,
Karangetang has had more than 40 recorded eruptions since 1675.
Twentieth-century eruptions have included frequent explosions, sometimes
accompanied by pyroclastic flows and lahars.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Karangetang reports
http://www.volcano.si.edu/gvp/volcano/region06/sangihe/karang/var.htm from
the Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m; All times are
local (= UTC 10 hours)
During the week lava entered the sea at a moderate rate at the E Kupapa`u
entry. On 18 July at 1803 a M 3.5 earthquake rattled though the lower east
rift zone of Kilauea. Surface flows were vigorous in two areas of the
current lava flow field; one in the E branch of the flow field at the base
of the Pulama pali scarp, and the other just SE of the shatter ring in the
W branch of the flow field. Generally, weak, steady tremor and a few
related long-period earthquakes continued beneath Kilauea's caldera. Near
Pu`u `O`o, the tremor alternated from weak, to moderate, to strong over
periods of several hours. Elsewhere, seismicity was at normal levels.
Tiltmeters in the summit area and along the east rift zone indicated no
significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http://www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
KRAKATAU Indonesia 6.10°S, 105.43°E; summit elev. 813 m
There were 728 shallow volcanic earthquakes at Krakatau during 9-15 July,
which was a significant increase in comparison to the previous week. No
visual observations were made. The volcano remained at Alert Level 2 (on a
scale of 1-4).
Background. The renowned Krakatau volcano lies in the Sunda Strait between
Java and Sumatra. Collapse of the ancestral Krakatau edifice, perhaps in
416 AD, resulted in a 7-km-wide caldera. Remnants of this volcano formed
Verlaten and Lang Islands; subsequently Rakata, Danan and Perbuwatan
volcanoes were formed, coalescing to create the pre-1883 Krakatau Island.
Caldera collapse during the catastrophic 1883 eruption destroyed Danan and
Perbuwatan volcanoes, and left only a remnant of Rakata volcano. The
post-collapse cone of Anak Krakatau (Child of Krakatau), constructed within
the 1883 caldera at a point between the former cones of Danan and
Perbuwatan, has been the site of frequent eruptions since 1927.
Source: Volcanological Survey of Indonesia http://www.vsi.dpe.go.id/
Krakatau Reports
http://volcano.si.edu/gvp/volcano/region06/krakatau/krakatau/var.htm from
the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
Volcanic activity at Mayon was similar to the previous week. During 17-23
July seismicity consisted of four high-frequency and 37 low-frequency
earthquakes, and 203 high-frequency short-duration harmonic tremors. An
average of 4,100 metric tons per day of SO2 was emitted from the volcano,
which was still above the baseline value of 500 metric tons per day. There
was an overall deflationary trend and the intensity of incandescence
observed at the crater ranged from barely visible to bright. Rockfalls
occasionally rolled from the crater SE towards the Bonga Gully. The volcano
remained at Alert Level 3 (on a scale of 0-5).
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Source: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Mayon Reports
http://www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from
the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
During 9-15 July volcanic activity at Merapi was similar to the previous
week. A total of 52 lava avalanches traveled SW to a maximum distance of
2.5 km down the Sat, Senowo, and Lamat rivers. Emissions from low-pressure
fumaroles rose to 755 m above the summit. The volcano remained at Alert
Level 2 (on a scale of 1-4).
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Merapi Reports
http://www.volcano.si.edu/gvp/volcano/region06/java/merapi/var.htm from
the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m
Several small-to-moderate sized emissions occurred at Popocatépetl that
were mainly composed of steam, gas, and small amounts of ash.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Sources: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html
Popocatépetl Reports
http://www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html from
the monthly Bulletin of the Global Volcanism Network
SEMERU Java, Indonesia 8.11°N, 112.92°E; summit elev. 3,676 m
Seismic data revealed that during 9-15 July activity was higher than in the
previous week. During this period 687 explosion events were recorded, as
well as 57 avalanches, and 11 tectonic earthquakes. The volcano remained at
Alert Level 2 (on a scale of 1-4).
Background. Semeru is the highest volcano on Java and one of its most
active. The symmetical stratovolcano rises abruptly to 3,676 m above
coastal plains to the S and lies at the southern end of a volcanic massif
extending N to the Tengger caldera. Semeru has been in almost continuous
eruption since 1967. Frequent small-to-moderate Vulcanian eruptions have
accompanied intermittent lava dome extrusion, and periodic pyroclastic
flows and lahars have damaged villages below the volcano. A major secondary
lahar on 14 May 1981 caused more than 250 deaths and damaged 16 villages.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Semeru Reports
http://volcano.si.edu/gvp/volcano/region06/java/semeru/var.htm from the
monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev.
1,030 m; All times are local (= UTC 4 hours)
The number of rockfalls increased (719) during 13-20 July in comparison to
the previous week (297), although most of them were very small.
Near-continuous rockfalls occurred on the S side of the lava dome, where
dome growth was concentrated. Numerous pyroclastic flows originated from
the S flank of the dome and moved eastward down the Tar River Valley.
Several pyroclastic flows also originated from the W side of the dome and
traveled short distances into the upper part of the Gages area. On 23 July
at 1145 a pilot reported spotting an ash cloud approximately 800 m above
the volcano. Satellite imagery at that time detected a faint ash-and-steam
plume and an occasional hot spot.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvomrat.com/,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
http://www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
During the week heavy rain remobilized ash deposited on the flanks of the
volcano, generating lahars, and several small-to-moderate eruptions
produced ash clouds. On 19 July lahars that traveled down the W flank of
the volcano reached the Baños-Riobamba highway. The Washington VAAC
reported that one of the larger eruptions during the week occurred on 20
July at 2104 and produced an ash cloud that rose to ~7.9 km a.s.l.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http://www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 519 of 997: Marcia (MarciaH) * Fri, Jul 27, 2001 (13:53) * 114 lines
********************
Mayon, Philippines
********************
From: Dan Shackelford
New eruption at Mayon volcano.
Strong eruption at Mayon volcano on 26 July, stronger than that of 24 June.
Around midnight Mayon explosive activity began again. At ~0200, lava
fountaining and pyroclastic flows commenced, leading to warnings being
issued. Powerful explosive activity began at 0756, lasting several hours,
with pyroclastic flows down the Bonga, Buyuan, and Basud gullies. The ash
cloud rose 10km over the crater.
From The Manila Bulletin :
Friday, 27 July 2001
Mayon erupts anew; Albay residents flee
Legazpi, 4 towns hit by ashfall
By ED DE LEON, ROLLY ALANO, & EUFEMIO MEDIAVILLO
LEGAZPI CITY - Mayon Volcano in Albay erupted anew at 7:56 a.m. yesterday,
sending a cauliflowershaped ash cloud up to 10 kilometers above its crater
and causing thousands of residents within the six-kilometer permanent
danger zone who had just returned to their homes to flee for safety.
The volcano, noted for its nearly perfect cone, last erupted on June 24.
As early as 3 a.m. yesterday, provincial disaster officials had already
warned residents living within the six-kilometer permanent danger zone and
the seven-kilometer extended danger zone facing the Bonga gully to be on
the alert after lava fountaining and pyroclastic flows were observed at
about 2 a.m. yesterday.
Albay Gov. Al Francis Bichara said they estimated that more than 20,000
persons will be initially evacuated from the 15 barangays located within
the permanent danger zone.
He said the evacuation is going on smoothly.
Col. Dante Bonifacio, commander of the 202nd Infantry Division and Joint
Task Force Mayon commander, said he immediately mobilized 12 Army trucks to
lead the evacuation operations.
Ed Laguerta, resident volcanologist at the Philippine Institute of
Volcanology and Seismology (Phivolcs) Ligñon Hill observatory here, said
that yesterday's eruption was stronger and wider in magnitude than the
series of eruptions on June 24.
He said that the massive lava-fountaining started at about 2 a.m. yesterday
and preceded by the series of eruptions carrying pyroclastic materials that
lasted for about two hours.
Ashfall, which covered the whole volcano, drifted towards this city and in
the towns of Sto. Domingo, Daraga, Camalig, and Guinobatan.
The Department of Health regional office here reported that it has already
released some 20,000 pieces of dust masks for disposal by the Provincial
Disaster Coordinating Center (PDCC) to the affected residents.
Newly installed Legazpi City Mayor Noel Rosal personally supervised the
evacuation of the residents from four barangays at the foot the volcano
near the boundaries of the six-kilometer permanent danger zone such as
Buyuan, Bonga Matanag and Mabinit.
She said that yesterday's eruption was stronger than the previous ones. She
added that this is the first time since the 1968 eruption that pebbles have
reached the town's poblacion.
Classes in this city and in the towns affected by the eruption were
immediately suspended by the Department of Education, Culture and Sports.
Volcanologists Laguerta and Ernesto Corpuz immediately surveyed the extent
of the pyroclastic flows around Mayon.
Alert level 5
LEGAZPI CITY - Ed Laguerta, resident volcanologist of the Philippine
Institute of Volcanology and Seismology (PHIVOLCS) here, yesterday raised
Mayon Volcano's alert level from 3 to 5 to warn residents living near one
of the world's most active volcanoes.
Alert level 5 means that Mayon is in hazardous eruption.
Evacuation centers in Legazpi City and Albay town underwent decamping when
PHIVOLCS lowered the alert level on the volcano from 4, which means that
hazardous eruption is possible within days) to alert level 3 last July 14..
The ash columns from yesterday's eruption of Mayon stayed longer in the sky
before wind sent them falling to Daraga, Legazpi City, and Sto. Domingo
towns.
It was the first time that Daraga and Legazpi experience ashfalls.
As of press time, the volcano was still exploding mildly, the explosions
preceded by long rumblings.
When Mayon erupted last June 24, more than 46,000 people were evacuated to
more than 30 evacuation centers in Albay.
Pyroclastic flows
The Philippine Institute of Volcanology and Seismology (Phivolcs) reported
yesterday that the strong eruption of the Mayon Volcano yesterday generated
pyroclastic flows on the Bonga, Buyuan, and Basud gullies.
It said Mayon emitted ashes 10 kilometers to the sky which drifted
south-southwest and some towards the general direction of Lidong, Sto.
Domingo, Albay.
It said the explosive activity continued till mid-morning yesterday and
signaled the start of the hazardous phase of the volcano's activity.
Phivolcs advised the public to be prepared at all times for more volcanic
blasts, pyroclastic flows and ground surges which may be generated by a
very high eruption column and further intensification of Mayon's volcanic
activity.
Evacuation
LEGAZPI CITY - Villagers living around Mayon Volcano were evacuated
immediately after the volcano unleashed its strongest explosion at 7:56
a.m. yesterday.
The evacuation operations became simpler as the residents were brought to
the same evacuation centers used during the eruption of Mayon last June 22.
As of 4 p.m. today, the Albay Provincial Social Welfare and Development
Office could not still give the number of people evacuated. But according
to Task Force Mayon, the number may reach 46,000 which is similar to the
number of persons brought to 51 evacuation centers in Albay and in Legaspi
City in the June 22 eruption.
As evacuation goes on, another explosion occurred at 3 p.m., sending ash
columns towards the direction of Guinobatan.
Ashfalls dropped faster to barangays near the foot of Mayon volcano due to
rains, creating lahar flows along river channels and making muddy ashes
that had piled up earlier along the Maharlika Highway from the 7:56 a.m.
explosion.
Topic 2 of 99 [Geo]: Vulcanism
Response 520 of 997: Marcia (MarciaH) * Fri, Jul 27, 2001 (13:54) * 68 lines
News reports on the latest Etna activity are available at:
http://dailynews.yahoo.com/h/nm/20010726/sc/italy_etna_dc_4.html
http://dailynews.yahoo.com/h/ap/20010726/wl/italy_volcano.html
***************************************
Aerosol Report - Etna eruption
***************************************
From: "Joseph M. Prospero"
Aerosol Report, 24Jul01: Aetna Eruption
Doug Westphal (NRL Monterey) has put together a very nice case study of the
eruption.
http://www.nrlmry.navy.mil/aerosol/Case_studies/20010722_etna/
Joseph M. Prospero
Professor and Director
Cooperative Institute for Marine and Atmospheric Studies
Rosenstiel School of Marine and Atmospheric Science
University of Miami
4600 Rickenbacker Causeway
Miami FL 33149
Tel: 305-361-4159
Fax: 305-361-4457
jprospero@rsmas.miami.edu
***************************
Etna satellite images
***************************
From: JPLNews@jpl.nasa.gov
(forwarded by Claude Desgroseilliers )
Space View Shows Two Plumes from Mt. Etna Eruption
MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov
IMAGE ADVISORY July 25, 2001
SPACE VIEW SHOWS TWO PLUMES FROM MT. ETNA ERUPTION
Two volcanic plumes from Mt. Etna composed of different materials are
visible in new images from NASA's Multi-angle Imaging SpectroRadiometer on
the Terra satellite. A bright, brownish plume drifting southeast over the
Ionian Sea is made up primarily of volcanic ash -- tiny frozen fragments of
lava. A fainter, bluish-white plume, seen near the summit, contains very
fine droplets of water and dilute sulfuric acid. The images, taken July
22, 2001, are available at
http://www.jpl.nasa.gov/images/earth/volcano
The Multi-angle Imaging SpectroRadiometer, built and managed by NASA's Jet
Propulsion Laboratory, Pasadena, Calif., is one of several Earth-observing
experiments aboard Terra, launched in December 1999. The instrument
acquires images of the Earth at nine angles simultaneously, using nine
separate cameras pointed forward, downward, and backward along its flight
path. More information is available at
http://www-misr.jpl.nasa.gov .
JPL is a division of the California Institute of Technology in Pasadena.
Topic 2 of 99 [Geo]: Vulcanism
Response 521 of 997: Marcia (MarciaH) * Fri, Jul 27, 2001 (16:09) * 124 lines
******************************************
Alaska and Hawaiian Volcanoes 27 July 2001
******************************************
Volcano Watch - July 26, 2001
Surfing Cyberspace for Hawaiian Earthquakes
Surfers of our Hawaiian Volcano Observatory (HVO) web site might have
noticed that, earlier this year, we rolled out a modified web presentation
of earthquake activity in Hawai`i. An "After Dark in the Park" evening
talk at Hawai`i Volcanoes National Park in June also described our new web
pages and their operation.
Those familiar with earthquake web pages served from other U.S.
Geological Survey (USGS) offices should recognize similarities between our
"Recent Earthquakes in Hawai`i" web pages and these other pages. These
similarities are by no means coincidental.
Last fall, we installed a suite of computer programs to update our
earthquake web pages. This package was originally developed by Robert
Simpson of the USGS Earthquake Hazards Team in Menlo Park, California.
While the templates came from California, HVO staff dedicated a great deal
of effort toward implementing and customizing these utilities for our use
in Hawai`i. This allowed us to use a set of programs common to a number of
other seismic networks and to conform to a USGS style of earthquake web
page appearance.
Underlying all of the web page postings are the seismographic field
networks that provide data in continuous and real-time fashion to our
networks' operational centers. Ground vibrations, whether generated by
earthquakes, man-made sources, cultural disturbances, or ambient
conditions, are converted by our field hardware to electrical signals.
These electrical signals are then converted to radio transmissions to carry
information to HVO from as far away as Maui.
Once the radio signals are received and decoded at HVO, our computers
take over. The first step is to convert the seismic signals into digital
streams for computer processing and archiving.
Following the analog-to-digital conversion, we apply automated algorithms
to detect signals that might be produced by earthquakes. Additional
programs then attempt to estimate the arrival times of the principal
seismic waves. If these procedures are successful, an earthquake message,
including time, location and magnitude, is automatically generated.
Literally gigabytes of seismic data are scanned, processed, and recorded at
HVO each day.
The Recent Earthquakes programs receive the computer-generated
message and manipulate it so that an earthquake symbol, a text message, and
several seismograms can be posted on the web page. This is routinely done
within one or two minutes of the time of the earthquake. From our Recent
Earthquakes base map showing the island of Hawai`i, the maps and earthquake
symbols are programmed to provide additional information for any given
earthquake or to look at earthquakes from different regions with
appropriate mouse clicks. When a significant earthquake occurs, our web
pages should provide a reasonable look at the current activity.
While the overwhelming majority of earthquakes occur beneath the
island of Hawai`i, we also provide links to maps of Maui County and O`ahu
for the relatively infrequent, but still possible, seismicity there. Once
we have interactively reviewed the data, we update the web page posting to
include information drawn from other sources, possibly even adding or
deleting earthquakes the automated computer programs have misinterpreted.
The web pages hold two weeks of earthquake information. Data older
than two weeks automatically scroll off the web pages and are replaced by
the most recent activity. Interested parties can watch the earthquakes and
volcanoes themselves by surfing to http://hvo.wr.usgs.gov.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week. Lava moves away from the vent toward the
ocean in a network of tubes and descends Pulama pali in two separate areas.
Small surface flows, primarily ooze-outs from inflated areas, are
occasionally observed in the coastal flats. Lava continued to enter the
ocean in the area east of Kupapa`u throughout the week. The public is
reminded that the ocean entry areas are extremely hazardous, with
explosions accompanying frequent collapses of the new land. The steam cloud
is extremely hot, highly acidic, and laced with glass particles.
There were no earthquakes reported felt during the week ending on
July 26, 2001, but nearly a dozen earthquakes, one with a magnitude of 4.1,
were located on Lo`ihi Volcano.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
U.S. Geological Survey
Hawaiian Volcano Observatory
PO Box 51, Hawaii National Park, HI 96718
Phone (808) 967-7328 FAX (808) 967-8890
Weekly Update Friday, July 27, 2001 11:30 AM ADT (1930 UTC)
ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
in color code GREEN. All are at or near normal levels of background
seismicity. AVO did not detect ash plumes or significant elevated surface
temperatures in the vicinity of any volcano.
Abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of Alaska's volcanoes (907) 786-7478
Tom Murray, Scientist-in-Charge, USGS
tlmurray@usgs.gov (907) 786-7497
Carolyn Bell
Acting Public Affairs Officer
U.S. Geological Survey
Mail Stop 119 National Center
Reston, VA 20192
Topic 2 of 99 [Geo]: Vulcanism
Response 522 of 997: Marcia (MarciaH) * Sat, Jul 28, 2001 (17:57) * 110 lines
Mayon eruptions; Japan update
*********************************
Mayon, Philippines
*********************************
From: Dan Shackelford
Further eruptions at Mayon
Two further large eruptions at Mayon took place from 1440 - 1500 on 26 July
and 1749 - 1810 on the 27th with pyroclastic flows sweeping down the SE, S,
SW and W flanks of the volcano with ash clouds from summit crater to
perhaps 10km in height. On 27 July, lava was seen flowing down the Bonga
Gulley (SE flank) for at least 3.5km in length. Significant seismicity and
edifice deformation are also occurring.
From: http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
Mayon Volcano Bulletin
8:30 A.M. 27 July 2001
Following initial eruption at 7:56 AM yesterday, two more eruption episodes
occurred. The second explosive eruption commenced at 2:20 PM until 3:00 PM
yesterday and the third event was recorded from 5:49 PM to 6:10 PM
yesterday. These eruptions produced life-threatening pyroclastic flows,
which swept mainly the Bonga Gully in the southeast and the Basud Gully to
the East. Smaller pyroclastic flows ran through the Miisi and Anoling
Gullies in the south, and other flows occurred in the southwest and western
sectors. All pyroclastic flows were contained within the six (6)
kilometer-radius Permanent Danger Zone (PDZ). Inclement weather precluded
direct observation of the ash plume for the second and third eruption
episodes but based on ashfall in Legaspi City and neighboring towns, it is
estimated that the ash columns were similar to the first eruption of 7:56
AM and reached 10 kilometers high and fanned through the south-southwest
and southeast.
At present, Mayon has entered an effusive eruptive phase, which means that
lava is flowing in the Bonga Gully. Observations earlier this morning
indicate that the toe of the advancing lava flow is at about 700 meters
elevation or approximately 3.5 kilometers from the summit and well within
the 6 kilometer PDZ. However, at the present rate of its movement, this
lava flow is unlikely to go beyond the PDZ.
Due to ongoing tremors and significant ground deformation that are being
detected PHIVOLCS expects more explosive activity in the following days.
Thus, Alert Level 5, meaning Hazardous Eruption in Progress, remains in
effect over the volcano. PHIVOLCS reminds the public to keep away from the
six (6) kilometer-radius PDZ and the seven (7) kilometer-radius Extended
Danger Zone (EDZ) because these areas are highly susceptible to hazardous
pyroclastic flows, volcanic surges and blasts. In addition, residents in
areas adjacent to river channels originating from the volcano should be
always on the alert and ready to move to higher ground because newly
deposited volcanic material may be remobilized into life threatening
torrential stream flows and lahars.
PHIVOLCS
******************************************
Satsuma-Iwojima and Suwanose-jima, Japan
******************************************
From: Dan Shackelford
Satsuma-Iwojima has been showing continuous tremor since 20 July (as of 26
July), and ashfalls have intermittently fallen during April, May, June, and
July. Meanwhile, Suwanose-zima continued its decades-long episode of
activity with further ash eruptions noted on 26 July, ash clouds rising
1300m with accompanying tremor.
From: http://hakone.eri.u-tokyo.ac.jp/vrc/erup/erup.html
(maintained by S. Nakada, VRC-ERI, U-Tokyo)
----------------
SATSUMA-IWOJIMA (SATSUMA-IOJIMA) VOLCANO, Kyushu
(704 m, 30o47"22"N, 130o18'27"E))
(7/26/01)
JMA issued the Observation Report #4 on Satsuma-Iwojima volcano on 23 July
2001. A continuous volcanic tremor event had occurred since 20 July at this
volcano. The JMA seismometer installed about 700 m SW of Iwo-dake had
caught small volcanic earthquakes since January in 2000. The daily number
ranges from 50 to 110. Small volcanic tremor events were sometimes
observed. According to the Iwo-jima Branch of the Mishima Village Office,
ash fall was observed during 19 to 21 July, following the 9 April, 15 and
29 May, and 12 June events. The white plume was rising as low as 20 m above
the crater.
The daily number of earthquakes ranged from 30 to 90 during the period from
December 2000 to March 2001. Small volcanic tremors had been observed since
December. Faint ash falling was often observed.
Information: JMA_Fukuoka, Naokuni Uchida: n-uchida@redc-fk.eqvol.kishou.go.jp
---------------
SUWANOSE-JIMA VOLCANO, SW Islands, Kyushu
(29o52'38"N, 128o13'28"E)
(7/26/01)
Active eruptions had continued at Otake of Suwanosejima. JMA issued the
Observation Reports #6 and 7 on Suwanosejima Volcano on 26 July. According
to them, the height of the volcanic plume drifting southward was 1300 m
above the crater at 14:30. The JMA seismometer installed about 2 km SW of
the crater, recorded explosion at 05:01, 05:58, 09:35 and 10:55. Volcanic
tremor had continued since around 22h of 25 July. According to the
Suwanosejima Branch of the Toshima Village Office, ash was falling in the
26 July morning.
Information: JMA_Fukuoka, Naokuni Uchida: n-uchida@redc-fk.eqvol.kishou.go.jp
Topic 2 of 99 [Geo]: Vulcanism
Response 523 of 997: Marcia (MarciaH) * Sat, Jul 28, 2001 (17:59) * 79 lines
*****************************************************
AGU Session: Understanding Volcanoes through
Multiparameter Measurements and their Interpretation:
A Session in Memory of Bruno Martinelli
*****************************************************
From: Peggy Hellweg
Understanding Volcanoes through Multiparameter Measurements and their
Interpretation: A Session in Memory of Bruno Martinelli
We cannot make worthwhile predictions about a volcano's activity without
thoroughly understanding the processes occurring inside it. This was a
basic tenet of Bruno Martinelli. It is only possible to understand volcanic
processes if we can understand the dynamic properties and movements of the
fluids involved as well as the volcano's internal structure. It is
impossible to deduce this information from the observation of a single
volcanic parameter such as seismicity. Rather, we must combine insights
from the joint interpretation of measurements of many different physical
and physico-chemical phenomena, as well as observations of a volcano's
geological and petrological characteristics. We invite contributions to
this session describing systems for the joint and concurrent measurement
and analysis of several parameters, as well as the results and
interpretation of data from such systems.
Convenors:
Dr. Peggy Hellweg; Berkeley Seismological Laboratory, UC Berkeley, Berkeley
CA 94520, USA; phone: ++1-925-254-0569; fax: ++1-415-840-0071; email:
geo_enterprise@compuserve.com
Dr. Marta Calvache; Observatorio Vulcanologico de Pasto; PO Box 1795;
Pasto; COLOMBIA; phone: ++57-27-314752; fax: ++57-27-31 05 14; email:
mcalvache@ingeomin.gov.co
Dr. Susanna Falsaperla, Istituto Nazionale di Geofisica e Vulcanologia,
Sezione di Catania; Piazza Roma, 2; 95123 Catania; ITALY; phone:
++39-95-448084; fax: ++39-95-435801; email:susanna@iiv.ct.cnr.it
**************************************************
AGU Session: Volcanic Observations from Space:
New Results from the EOS Satellite Instruments
**************************************************
From: Michael Ramsey
Michael Ramsey (University of Pittsburgh) and Luke Flynn (University of
Hawaii) would like to announce a newly-approved special session for the
Fall AGU meeting in San Francisco, CA. The details are listed below, but
if you have any questions or comments, please contact one of us.
"Volcanic Observations from Space: New Results from the EOS Satellite
Instruments"
In 1991, NASA launched a comprehensive program to study the Earth as one
environmental system, now called the Earth Science Enterprise. The program
began with several free-flying satellites and continued with the launch of
Landsat 7 in 1999 and Terra, the first Earth Observing System (EOS)
satellite, later that year. Followed by the Earth Observing-1 platform
late in 2000, the EOS satellite instruments have now entered a planned 18
year global monitoring phase. There are currently six EOS-designated
satellites carrying 16 instruments, all of which are providing integrated
measurements on the interactions between the Earth's global cycles.
Included in this effort, are the science investigations which examine the
solid Earth cycle and the natural hazards that are an inevitable result.
Higher spatial, spectral, and temporal resolution EOS data have spawned a
variety of new algorithms designed to study numerous aspects of
volcanology. Thermal anomaly detection, plume chemistry and mass flux,
lava composition and textural properties, the interaction of ash with the
natural and human environment, and mitigation of hazards are but a few of
the topics being addressed with remote sensing. This session is designed
to showcase the current research in volcanic systems and processes using
the new EOS satellite data sets. It is also intended to provide a forum
for field, aircraft, or other satellite-validated EOS observations of
volcanic edifices and the processes affecting them.
Conveners: Michael Ramsey, Department of Geology & Planetary Science,
University of Pittsburgh, Pittsburgh, PA 15260, phone: 412-624-8772,
ramsey@ivis.eps.pitt.edu and Luke Flynn, Hawaii Institute of Geophysics &
Planetology, University of Hawaii at Manoa, Honolulu, HI 96822, phone:
808-956-3154, flynn@higp.hawaii.edu
Topic 2 of 99 [Geo]: Vulcanism
Response 524 of 997: Marcia (MarciaH) * Sat, Jul 28, 2001 (18:06) * 103 lines
*********************************
KVERT Information Release 46-01:
July 27, 2001
*********************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 46-01
Friday, July 27, 2001, 12:58 KDT (23:58 UTC)
The following Release was received by the Alaska Volcano Observatory
via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are Kamchatkan Daylight Time, 21 hours ahead of ADT.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS GREEN.
According to seismic and satellite data, an extrusive process has begun at
the dome of Bezymianny.
Seismic activity at the volcano increased above background on July 25 as
shallow earthquakes and weak, long local seismic events (possible collapses
and/or avalanches) were recorded. On July 23-24 gas and steam plumes rose
200 - 700 m above the dome and extended east-southeast, southeast, and
northwest 10 km. On July 21-22 the volcano was quiet. At other times,
clouds obscured the volcano.
According to satellite image n12.01206 (AVHRR), at 07:18 on July 26 (18:18
UTC on July 25) a 3-pixel thermal anomaly had a maximum band 3 temperature
of 26.8 degrees C within a background near 8 degrees C. The anomaly had a
linear shape and southeast-trend from the summit.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity was above background the past week. Many small earthquakes
within the volcano's edifice and local seismic signals (explosions,
avalanches, collapses) were recorded at the volcano. Volcanic tremor
amplitude was, on average, 4.0x10-6 mps the entire week.
Observers in Klyuchi reported that on July 22-23 gas and steam plumes rose
100 - 500 m above the dome (2,600-3,000 m, 8,500-9,900 ft. ASL). At 19:10
KDT (06:10 UTC) on July 23 a gas and steam plume rose 1000 m above the dome
(3,500 m, 11,500 ft. ASL) and extended east 10 km. Observers also reported
that at 05:28 KDT on July 24 (16:28 UTC on July 23) an ash plume rose 2,500
m above the dome (5,000 m, 16,500 ft. ASL). At 08:10 KDT (19:10 UTC on
July 23) and at 16:30 KDT (03:30 UTC) on July 24 a gas and steam plume rose
2000 m and 1500 m above the dome (4,500 m, 14,800 ft. ASL and 4,000 m,
13,200 ft. ASL) and extended south 10 km. On July 21 the volcano was quiet.
On July 25-26 clouds obscured the volcano.
Satellite image n12.01203 showed a 1-pixel thermal anomaly of 17 degrees C
in a background of 5 degrees C at 06:48 KDT on July 23 (17:48 UTC on July
22). Two pixels at/near saturation (49 degrees C) in a background of 30 to
35 degree C were seen at 18:17 KDT (05:17 UTC) on July 23 in image
n12.01204. A 2-3 pixel thermal anomaly was seen at the volcano in image
n12.101206 at 17:29 KDT (04:29 UTC) - two pixels were at saturation with a
third at 48 degrees C with background at ~30 degrees C. The anomaly also
appeared in band 4. A 3-pixel anomaly was also recorded in image n14.101206
at 18:27 KDT (05:27 UTC) on July 25. Temperatures were 38 ? 49 degrees C
with a background of ~28 degrees C. At 07:18 KDT on July 26 (18:18 UTC on
July 25) AVHRR image n12.01206 also revealed a 2-pixel anomaly at the
volcano. The maximum band 3 temperature was 33.8 degrees C within a
background near 9 degrees C. The anomaly was again located near the SW
flank of the volcano.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was above background on July 21 and 22. Six MI greater than 2
earthquakes were registered. Weak intermittent spasmodic volcanic tremor
was recorded the entire week. At 00:32 KDT (11:32 UTC on July 21) and at
16:21 KDT (03:21 UTC ) on July 22 a series of shallow earthquakes within
the volcano's edifice were registered. On July 22-23 gas and steam plumes
rose 150 - 250 m above the crater (4,900-5,000 m, 16,200-16,500 ft. ASL).
At 19:10 KDT (06:10 UTC) on July 23, a gas and steam plume rose 1000 m
above the crater (5,750 m, 18,900 ft. ASL) and extended north-northeast. On
July 24 the volcano was quiet. On July 21 and 25-26 clouds obscured the
volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
On July 25-26 clouds obscured the volcanoes. When visible, both volcanoes
appeared quiet. Seismic activity was at background levels. Weak spasmodic
volcanic tremor was registered.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006
RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
Topic 2 of 99 [Geo]: Vulcanism
Response 525 of 997: Marcia (MarciaH) * Sat, Jul 28, 2001 (18:09) * 75 lines
********************************************
GVP/USGS Weekly Volcanic Activity Report,
26 July Mayon Update
********************************************
From: Gari Mayberry
GVP/USGS Weekly Volcanic Activity Report
26 July 2001 Mayon Update
http://www.volcano.si.edu/gvp/usgs/
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m; All times are local (= UTC + 8 hours)
Mayon began a new eruptive episode near midnight on 25 July when explosive
activity fed pyroclastic flows for approximately 2 hours. By 0200 massive
lava fountaining began and around 0300 residents within the 6 km radius
permanent danger zone were evacuated. At 0756 on 26 July, approximately 4
hours after evacuations began, a large eruption produced an ash cloud that
rose 10 km above the volcano and drifted to the SE. Pyroclastic flows
traveled up to 5.5 km to the E and SE down the Bonga, Buyuan, and Basud
gullies. Also, lava fountains rose up to 60 m above the volcano. Rain mixed
with deposited ash, generating lahars that flowed along river channels.
Later in the day eruptions occurred at 1420 and 1759. According to the
Manila Bulletin, Ed Laguerta, resident volcanologist at PHIVOLCS said that
the 0756 eruption was stronger and wider in magnitude than the series of
eruptions on 24 June 2001.
By the evening of 26 July the 6 km radius danger zone had been increased to
8 km and approximately 40,000 people had been evacuated. Ash fell in the
towns of Santo Domingo, Legazpi, Daranga, and Camalig in the Albay
province. It is unusual for ash to fall in Daraga and Legazpi and the
airport in Legazpi City was closed. Television reports stated that ash fell
as far as the Sorsogon province, ~60 km S of the volcano. There were
reports of ash deposits as much as 2.5 cm thick in some areas, but there
were no immediate reports of injuries or damage. As of the evening of 26
July the volcano continued to release steam and ash accompanied by
explosion-type earthquakes and harmonic tremor.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Sources: PHIVOLCS http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Tokyo VAAC http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html,
Reuters
http://news.excite.com/news/r/010725/23/international-philippines-volcano-dc,
Associated Press http://news.excite.ca/news/cp/010726/04/thousands-flee-as,
CNN
http://www.cnn.com/2001/WORLD/asiapcf/southeast/07/26/phil.mayon/index.html,
ABS-CBN
http://www.abs-cbnnews.com/ABS/INEWS-JUL2001.NSF/Provincial/20010727010,
Manila Bulletin http://www.mb.com.ph/MAIN/2001-07/MN072701.asp
Mayon Reports
http://www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from
the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Topic 2 of 99 [Geo]: Vulcanism
Response 526 of 997: Marcia (MarciaH) * Sun, Jul 29, 2001 (18:32) * 30 lines
Why it is not smart to pay proper respect for Madame Pele or any other volcano.
TV
crew tapes HVO geologist with sample of lava taken from the river.
The view is
looking into the wind, which blows hot air toward camera and produces intense
heat shimmer. Note that the foreground is reasonably sharp but the poor camera
man appears almost pixelated. The still photographer lost hair to Pele as this image
was taken.
Melted shoulder strap on expensive
pack. Note rocks imbedded in the melted strap. One of the team laid the pack
across a crack in the pahoehoe without first checking the temperature. The crack
was blistering hot from heat escaping out of the tube. As a result the pack is
history, and a certain someone is a bit wiser.
http://hvo.wr.usgs.gov/kilauea/update/main.html
Topic 2 of 99 [Geo]: Vulcanism
Response 527 of 997: Marcia (MarciaH) * Tue, Jul 31, 2001 (21:12) * 50 lines
*********************************
KVERT Information Release 47-01:
July 31, 2001
*********************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 47-01
Tuesday, July 31, 2001, 17:50 KDT (04:50 UTC)
The following Release was received by the Alaska Volcano Observatory
via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are Kamchatkan Daylight Time, 21 hours ahead of ADT.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS ORANGE.
Seismic activity was above background levels on July 25-27. On July 28
seismic activity decreased and remained at background levels on July 28-31.
Weak long local seismic events (possible collapses, avalanches) were
registered on July 25-31. Weak shallow earthquakes were recorded on July
25-26 and 29.
According to visual data from Kozirevsk, a weak fumarolic activity above
the dome was observed on July 30-31. On July 27-29 clouds obscured the
volcano.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006
RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
Topic 2 of 99 [Geo]: Vulcanism
Response 528 of 997: Marcia (MarciaH) * Tue, Jul 31, 2001 (21:15) * 268 lines
X-Sender: iki@popd.ix.netcom.com
***************************
Mayon, Philippines: Update
***************************
From: Dan Shackelford
The 29 July bulletin on Mayon from PHIVOLCS shows that although the lava
flow has stagnated, very high SO2 rates, inflation, and bright summit glows
suggest magma is still entering the system and that there is an active
magma supply ongoing. Pressure might still be increasing internally.
From: http://www.phivolcs.dost.gov.ph/vmepd/mayon_bulletin.htm
Mayon Volcano Bulletin
7:30 A.M. 29 July 2001
Mayon remains in a restive state as shown by active seismicity, high gas
emission rates and persistent incandescence of the summit area. Ninety-six
(96) high-frequency^Vtype short duration tremors were recorded and these
were apparently produced by lava fragments that detached from the summit
and from new lava flow deposits on the southeast slopes. Sulfur Dioxide
output rates amounted to 8,250 tonnes per day (t/d) which means that the
volcano is emitting very high amounts of gases associated with an active
magma supply within the volcano. Ground deformation measurements also
indicate a possible accumulation of pressure within the edifice. The
persistent glow at the summit, at Intensity II to III (fair to bright) is a
manifestation of the intense heat being generated by summit lava deposits
which can only be caused by an active magma system. This is in contrast to
diminishing glow of lava flow deposits that are cooling down with exposure
to the weather.
The net condition of Mayon described above reflects an active magma system
that is possibly accumulating pressure. If such pressure continues to
build up in the following days, an explosive eruption may recur. PHIVOLCS,
therefore, reminds the public that Alert Level 5 is in effect over the
volcano. The six (6) kilometer-radius PDZ and the seven (7)
kilometer-radius Extended Danger Zone (EDZ) should be off-limits at all
times because these areas are highly susceptible to the adverse effects of
pyroclastic flows, volcanic surges and directed blasts. Residents near
river channels originating from the volcano, especially in the southeast,
are advised to be vigilant during episodes of intense rainfall because hot
pyroclastic deposits may be remobilized as life-threatening stream flows
and lahars.
PHIVOLCS
*****************************
Tongariro, New Zealand
*****************************
From: Dan Shackelford
Slight increase in Tongariro's seismicity.
Since Feb 2001, New Zealand's Tongariro volcano has shown a slight increase
in seismicity, near its Te Maari craters. No change in the chemistry of its
fumaroles or springs have accompanied this seismicity. Alert level remains
unchanged.
From: http://www.gns.cri.nz/earthact/volcanoes/bulletins/220701.htm
SCIENCE ALERT BULLETIN: Tongariro V01/01
0900h 20 July 2001 (Friday)
Earthquake activity, Mt Tongariro
Small volcanic earthquakes have been recorded beneath Mt Tongariro since
February 2001. These by themselves do not give reason to change the Alert
Level. The Alert Level for Tongariro remains at level 0.
As part of our routine monitoring of seismic activity, we have recorded
several volcanic earthquakes per month at Mt Tongariro since at least
February. These earthquakes are very small and have only been well recorded
by one seismometer in our permanent network. Without data from at least
three seismometers it is not possible to locate the exact source of these
volcanic earthquakes.
To better understand the significance of these earthquakes we have:
deployed portable seismic recorders on Mt Tongariro
reviewed other available seismic data
conducted sampling of selected hot springs, crater lakes and fumaroles in
the area.
The review of seismic data has shown that these small volcanic earthquakes
have been present since at least February 2001, while the analysis of data
from a portable array operated by Cambridge University (January-May) has
allowed us to locate one of these events near the Te Maari craters. Results
available to date from water and gas sampling show no changes in the
chemistry of the springs or fumaroles.
Mt Tongariro is a volcano complex that lies to the north of Ngauruhoe. It
consists of numerous craters and vents. Te Maari craters lie about two
kilometres east of Ketetahi hot springs on the north side of Mt Tongariro.
The Te Maari craters are the last craters to be active on Tongariro. Small
ash eruptions were recorded from these craters in 1869 (accompanied by a
violent earthquake), June 1886, November 1892 and November-December 1896.
At this time we have no reason to believe that an eruption will occur at Te
Maari in the near future. However we will continue to monitor the
situation. Based on the data available to date there are no reasons
significant enough to change the Alert Level. The Alert level for Tongariro
remains at level 0.
Brad Scott
Duty Volcanologist
http://www.gns.cri.nz/earthact/volcanoes
*****************************
Indonesian Updates
*****************************
From: Dan Shackelford
From Suswati
Weekly Report No. 614
30 April - 6 May 2001
Marapi
Sumatera, Indonesia
0022'47,72" N, 100028'16,71"E
summit elevation 2891,3 m
Marapi explosion activity is continuing although the intensity less than
previous week. At least, observer reported 4 times of explosion, produced
blackish ash which towered until 1200 m height. Seismograph still dominated
with volcanic earthquakes, data listed as follow: 27 events of deep
volcanic (VA), 22 events of shallow volcanic (VB), and 4 events of explosion.
Marapi volcano is in level 2
Merapi
Central Java; 7032.5' S, 110026.5' E
Based on visual observations, solfatara was commonly in white thin-medium
color, low in pressure, and hit a maximum height 925 m above the summit.
During the period observer noticed 109 events of lava avalanche, traveled
2.5 km to Sat, Senowo, Lamat and Bebeng rivers. Observer also reported 4
times of minor pyroclastic flow, entered to the Sat, Lamat and Senowo
rivers with the maximum distance was about 1.5 km to the Sat river. The
dominant earthquake during the week was avalanche earthquake.
Merapi volcano is in level 2.
Lokon
North Sulawesi; 1021.5' N, 124047.5' E
Lokon activity during the reporting time which could observed from
Kakaskasen post observatory was plume emission from Tompaluan crater, have
a white medium-thick color and 50-250 m height. Seismograph recorded 0.5-1
mm amplitude of tremor volcanic earthquakes. Detail seismicity were: 1
event of shallow volcanic (VB), 36 events of tectonic, and 5 events of
tremor volcanic earthquake.
Lokon volcano is in level 2.
Inelika
Central Flores; 8044' S, 120059' E
Seismograph didn't record any seismicity within the week, and also no data
from visual observations because Inelika summit was covered by cloud during
the time.
Inelika volcano is in level 2.
Karangetang
Siau island; 2047' N, 125029' E
Visual observation could not be done well through the week, but observers
reported that they still heard low-medium of thundering sound from the
volcano. They also noticed 25 m of red colored reflection from the summit
at night view. No seismicity data within the week.
Karangetang volcano is in level 2.
Ijen
East Java;803.5' S, 114014.5' E
Best on instrumental monitoring Ijen activity seems more than normally.
That was marked with an occurring of volcanic earthquake in seismic
recorder. Lists of data were: 4 events of shallow volcanic (VB) and 6
events of tectonic earthquake.
Ijen volcano is in level 2.
Semeru
East Java; 806.50' S, 112055' E
Semeru seismicity still high but less compare to the week before. There was
not volcanic earthquake within the report, but seismograph recorded an
increasing of explosion earthquake. Complete seismicity listed below: 782
events of explosion, 96 events of avalanche, and 7 events of tectonic
earthquake.
Semeru volcano is in level 2.
Anak Krakatau
Sunda Straits, 606'5.8" S, 105025'22.3" E
By visual observations to the volcano within the week, observers reported
that sulfur deposits around it was in yellow color. That was indicated that
temperature of volcano edifice decrease than before. They also reported
that amounts of volcanic earthquakes less than before. Complete data were:
3 events of deep volcanic (VA), 52 events of shallow volcanic (VB), and 1
event of tectonic earthquake.
Anak Krakatau is stated in level 2.
G. Soputan
North Sulawesi,124:41'12"N, 1:6'20"E
There was no data from instrumental monitoring because seismograph did not
work during the week. But from visual observation observers noticed that
white thin color of plume emission is ongoing and reached 100 m height.
Soputan is stated in level 2.
G. Batur
Bali Island115.370 N, 8.240 E, summit elevation 1717 m
Evaluation on 3 May, to the seismicity and visual observations data of
Batur volcano since January to April 2001 shows that Batur activity is
decrease and more quite. Volcanic earthquakes within January-April, 2001
period recorded 6, 10, 20, and 6 events for each month respectively with
the depth was about 2-5 km under the summit. Based on that data, level of
Batur activity changed from level 2 to level 1 (lewest level, out of 4
alert level).
Batur volcano is in level 1.
***********************************
Weekly Report No. 624
9-15 July, 2001
Karangetang
Siau island; 2047' N, 125029' E
Within the period, Karangetang seismicity was dominated with small
explosion, avalanche and multiphase earthquake. Visual observations to the
summit noticed plume emission from main crater was in white medium - grey
color, also lava avalanche and lava flow are continuing. Glowing lava
avalanche traveled 2500 m to Keting river, while lava flow entered to
Kahetang river as far as 750 m. At the end flow often occurred material
avalanche with the distance was about 1500 m to Batu Awang river. The
noising sound which accompanying the avalanche was heard from Karangetang
post observatory. Volcanic tremor was recorded uncountinuously with
amplitude of about 1-12 mm, while amplitude of avalanche earthquake was
about 1-25 mm. Lists of seismicity were: 16 events of deep volcanic (VA),
10 events of tectonic, 451 events multiphase, continuous of avalanche, 572
events of small explosion, and uncontinuous of tremor earthquake.
Karangetang volcano is in level 3.
Merapi
Central Java; 7032.5' S, 110026.5' E
White thin and low pressure of Merapi solfatara is ongoing and hit 755 m
above the summit. Lava avalanche occurred 52 times and entered to Sat,
Senowo and Lamat river as far as 2500 m. Until the report, seismic activity
was dominated with avalanche earthquake.
Merapi volcano is in level 2.
Lokon
North Sulawesi; 1021.5' N, 124047.5' E
Lokon activity is ongoing and seems increase based to the seismic data.
Although just reached about 25-200 m of height, Tompaluan crater still
produced smog emission. Seismograph recorded an increasing number of
especially in volcanic earthquake, but not significant. Complete data
listed below: 11 events of deep volcanic (VA), 14 events of shallow
volcanic (VB), 42 events of tectonic and uncontinuous tremor earthquake.
Lokon volcano is in level 2.
Ijen
East Java;803.5' S, 114014.5' E
Visual observations to the volcano could not be done well during the
rep[orting time, but seismograpg continued to record volcanic and
uncontinuous tremor earthquake. The maximum amplitude of tremor earthquake
was about 0.5-3 mm. Seismicity within 2 week later listed as follow: 1
event of deep volcanic (VA), 31 events of shallow volcanic (VB),
uncontinuous tremor, 2 events of small explosion and 7 events of tectonic
earthquake.
Ijen volcano is in level 2.
Semeru
East Java; 806.50' S, 112055' E
Within the period, visual observations to the edifice of volcano were
obscured by the haze. But by instrumental monitoring Semeru activity is
continuing and more than normally. Seismograph continued to record amounts
of avalanche and explosion earthquakes, which increase compare to the week
before. Detail data listed below: 687 events of explosion, 57 events of
avalanche and 11 events of tectonic earthquake.
Semeru volcano is in level 2.
Anak Krakatau
Sunda Straits, 606'5.8" S, 105025'22.3" E
A significant increasing was shown from Krakatau activity. It was
represents from the high of shallow volcanic events during the period.
Lists of seismicity were: 53 events deep volcanic (VA), 728 events of
shallow volcanic (VB) and 20 events of tectonic earthquake. No data based
on visual observations within the week.
Anak Krakatau is stated in level 2.
G. Soputan
North Sulawesi,124:41'12"N, 1:6'20"E
Observers reported that visual activity of Soputan volcano was still marked
with ejection of white thin-medium plume which rose about 75 m height.
Seismicity still dominated with avalanche and tectonic earthquakes.
Complete seismic records were: 3 events of deep volcanic (VA), 48 events
tectonic and 201 events of avalanche earthquake. Since 14 July seismograph
has got a problem.
Soputan is stated in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 529 of 997: Marcia (MarciaH) * Wed, Aug 1, 2001 (01:28) * 1 lines
Rob, now that cheryl has welcomed you - I can grovel and apologize for messing up your volcanology club or was it the group?! Now, if I can steal DONALD Boom's stuff or convince him to post it here I will create him a topic and keep my long winded reports off this otherwise-interesting topic! David is going to be a hard sell - he has so little time - commuting and work and sleeping seem to make most of his day. I rarely hear personal things from him simply due to lack of time for it. However, that should change when he is married and has a shorter commute.
Topic 2 of 99 [Geo]: Vulcanism
Response 530 of 997: Marcia (MarciaH) * Wed, Aug 1, 2001 (18:50) * 33 lines
Liam has sent something you are not going to believe. Madame Pele will NOT be amused!
Cosmic Collision May Have Created Hawaii
By Michael Paine
Special to SPACE.com
posted: 09:04 am ET
01 August 2001
It's bad enough when, every few million years, an asteroid
rocks our planet. It's worse if the impact triggers regional or
global volcanic activity, which is not only hazardous to nearby
plants and animals but can choke Earth's atmosphere with
deadly gases for months or years.
But there's also a possible bright side, like the birth of nice
places like Hawaii.
For more than three decades, scientists have explored the
question of whether an asteroid impact could cause
significant volcanic eruptions, hot spots that spring up out of
nowhere and create new landforms or rearrange old ones. The
process might have given birth to the Hawaiian islands, for
example. The idea of linking space rocks and lava goes back
to at least the 1960s, and in recent months the debate has
heated up like a volcano ready to erupt.
Though no firm answers have emerged, controversial
computer modeling in recent years has shown what might
happen, and why.
The rest of the story and links... http://space.com/scienceastronomy/solarsystem/volcano_asteroid_010731.html
Topic 2 of 99 [Geo]: Vulcanism
Response 531 of 997: Marcia (MarciaH) * Wed, Aug 1, 2001 (21:19) * 37 lines
*****************************************************
AGU Session: Conduit processes during explosive
basaltic eruptions
*****************************************************
From: Andy Harris
Conduit processes during explosive basaltic eruptions
Deadline for electronic abstracts is September 6, 1400 UT. Please
submit abstracts to this session via the AGU web-site by this date if
you are interested in contributing to this session.
Description -- This special session will present results from
experiments aimed at understanding conduit processes during explosive
basaltic eruptions from Strombolian to Hawaiian-fountaining. New
insights into these processes have been gained through coincident,
multidisciplinary studies using techniques such as infrasound, seismics,
thermal monitoring, OP-FTIR, and Doppler radar. These studies have lead
to an improved understanding of source mechanism, conduit advection,
degassing, crystallization, fragmentation level, eruption dynamics, and
pyroclast dispersal. We encourage submissions relating multidisciplinary
observations and physical modeling of dynamic processes of conduit
physics.
Convenors:
Maurizio Ripepe, Dipartimento di Scienze della Terra, Universita` di
Firenze, via LaPira, 4, 50121- Firenze, Italy, email:
maurizio@ibogfs.cineca.it, Fax: +39/55/218628, Tel: +39/55/2757479
Andy Harris, HIGP/SOEST University of Hawaii, 2525 Correa Road,
Honolulu, HI 96822, USA, email: Harris@higp.hawaii.edu, Fax: 808 956
6322, Tel: 808 956 3157
Matthias Hort, GEOMAR, University of Kiel, Wischhofstr. 1-3, D-24148
Kiel, Germany, email: mhort@geomar.de, Fax: 431 600 2698, Tel: 431 600
2645
Topic 2 of 99 [Geo]: Vulcanism
Response 532 of 997: Marcia (MarciaH) * Wed, Aug 1, 2001 (21:22) * 18 lines
*************************
IAVCEI Wager Medal
*************************
From: Steve McNutt
WAGER MEDAL TO BE AWARDED IN 2002
Nominations are invited for the Wager Medal from the IAVCEI membership. This
Wager Medal honours the memory of Professor L.R. Wager of the University of
Oxford, who died in 1965. The award is to a young scientist (under 40 years of
age) on 31 December of the year preceding the IAVCEI meeting at which the
award is made. The 2002 medal will be presented at the meeting on Martinique
in May 2002 to mark the centenary of the Mont Pelee eruption of 1902. The
award is for outstanding contributions to the study of volcanic rocks,
particularly in the eight-year period before time of the award.
Previous Medal Recipients have been Jon Davidson and Giovanni Macedonio
(1997), Colin Wilson and Claude Jaupart (1993) and Charlie Bacon (1987)
Topic 2 of 99 [Geo]: Vulcanism
Response 533 of 997: Marcia (MarciaH) * Thu, Aug 2, 2001 (15:54) * 14 lines
Etna Eruption Eases, Scientists Find Water in Lava
August 02, 2001 04:33 PM ET
ROME (Reuters) - The fireworks subsided on Mount Etna on
Thursday as the volcano's two-week-long eruption eased, but
with smoke continuing to billow out experts warned it was too
early for civil protection officials to let down their guard.
As Europe's most active volcano oozed lava at its slowest
rate in days, excited scientists said preliminary studies
showed traces of water in a mineral that had not been
present in the lava for 15,000 years.
More... http://reuters.com/news_article.jhtml?type=sciencenews&StoryID=144614
Topic 2 of 99 [Geo]: Vulcanism
Response 534 of 997: Marcia (MarciaH) * Thu, Aug 2, 2001 (17:22) * 33 lines
Liam the incredible with more goodies about Mt Etna:
GOME, ATSR and SAR keep watch over Etna
In the first major eruption since 1992, Etna, Europe s most active volcano, is spewing out lava, ash, smoke and rocks in a
pyrotechnic display which is threatening nearby towns and infrastructure. Instruments on board ESA s European Remote
Sensing satellite ERS-2 are carefully monitoring the volcano s activity.
Although residents of the nearby village of Nicolosi in Sicily, Italy, are used to the 3310-metre volcano springing into life
every few months, this is the first major eruption since 1992, when for the first time explosives were used to deviate the flow
of lava away from populated areas. For more than two weeks the Italian authorities have been working day and night, trying
to divert the flow of lava which is rolling down Etna s slopes at speeds which can reach 2 metres per minute. A Herculean
task which has to be repeated, as quickly as possible, each time the lava overruns the man-made barriers.
Instruments on board ERS-2 monitor the volcano s movements, temperature and gas emissions. The most recent images
from the Global Ozone Monitoring Experiment (GOME) instruments, which provide information on trace gas levels in the
atmosphere, show that the level of sulphur dioxide released by the volcano are ten times higher than normal. This area of
high concentration can be found up to 1000 km away and covers an area almost the size of Germany.
Another instrument on board ERS-2, known as the Along Track Scanning Radiometer (ATSR), measures the temperature
of the Earth s surface and clearly shows the plume of smoke arising from the volcano s crater. By combining images from
ATSR and GOME it can be seen that the visible plume of the volcano, consisting of water vapour and dust, has a far
smaller extent than the chemical pollution in the atmosphere.
Monitoring Etna is not just a one-off operation. It is now over 10 years since ESA s ERS satellites first began providing
environmental data. Instruments on board the ERS satellite constantly keep watch over the Earth and provide precise and
timely environmental data for users. In fact, the Synthetic Aperture Radar (SAR) data provided by ERS-1 and ERS-2 have
been a new source of information for vulcanologists who use a complex technique called SAR interferometry, to track
vertical movements of the volcano with a centimetre precision.
Volcanoes are unpredictable and Etna is no exception. Says Wolfgang Lengert, ESA ERS Mission Coordinator, no-one
can say for sure when this latest eruption will stop but the valuable data supplied by 10 years of SAR data from the ERS
satellites is one of the tools that will be used to better understand this volcano.
Once Envisat, ESA's newest satellite for environment monitoring, is launched in a few months time, vulcanologists will have
yet more and better data to add to that already supplied by ERS, to help them with their studies of Mount Etna.
Topic 2 of 99 [Geo]: Vulcanism
Response 535 of 997: Marcia (MarciaH) * Thu, Aug 2, 2001 (23:25) * 7 lines
And, now, for my Bit of July dawn on Mount Etna:
Topic 2 of 99 [Geo]: Vulcanism
Response 536 of 997: Marcia (MarciaH) * Thu, Aug 2, 2001 (23:57) * 8 lines
This map of the flows will show you what you are looking at from
http://www.videobank.it/etna2001/
Topic 2 of 99 [Geo]: Vulcanism
Response 537 of 997: Marcia (MarciaH) * Fri, Aug 3, 2001 (00:08) * 5 lines
If you are interested in seeing Mt Etna in action with streaming live video and
audio, go here. http://www.videobank.it/etna2001/webcam1.asp
Thanks, J.Lyall@gns.cri.nz from geobullet@yahoogroups.com
Topic 2 of 99 [Geo]: Vulcanism
Response 538 of 997: Marcia (MarciaH) * Fri, Aug 3, 2001 (16:20) * 329 lines
GVP/USGS Weekly Volcanic Activity Report 25-31 July 2001
http://www.volcano.si.edu/gvp/usgs/
New Activity/Unrest: | Bezymianny, Russia | Etna, Italy | Mayon, Philippines |
Shiveluch, Russia | Soufrihre Hills, Montserrat |
Ongoing Activity: | Kikai (Satsuma-Iwo-jima), Japan | Kilauea, USA |
Popocatipetl, Mixico | Suwanose-jima, Japan | Tungurahua, Ecuador |
New Activity
BEZYMIANNY Kamchatka Peninsula, Russia 55.980N, 160.590E; summit elev. 2,882 m
KVERT raised the Concern Color Code
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm from Green to Orange
on 27 July after seismic and satellite data revealed that an extrusive process
began at Bezymianny's lava dome. On 23 and 24 July gas-and-steam plumes rose
200-700 m above the dome. On 25 July seismic activity at the volcano increased
above background levels as shallow earthquakes and weak, long local seismic
events (possible collapses and/or avalanches) were recorded. On 26 July a
linear three-pixel thermal anomaly was visible on satellite imagery trending
SE from the summit. The Concern Color Code was reduced to Yellow on 31 July
because seismic activity was at background levels during 28-31 July and only
weak fumarolic activity was observed.
Background. Prior to its noted 1955-56 eruption, Bezymianny volcano had been
considered extinct. Three periods of intensified activity have occurred during
the past 3,000 years. The latest period, which was preceded by a 1,000-year
quiescence, began with the dramatic 1955-56 eruption. That eruption, similar
to the 1980 event at Mount St. Helens, produced a large horseshoe-shaped crater
that was formed by collapse of the summit and an associated lateral blast.
Subsequent episodic but ongoing lava-dome growth, accompanied by intermittent
explosive activity and pyroclastic flows, has largely filled the 1956 crater.
Source: KVERT via the Alaska Volcano Observatory
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm,
Bezymianny Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/bezymian/var.htm from
the monthly Bulletin of the Global Volcanism Network
ETNA Sicily, Italy 37.730N, 15.000E; summit elev. 3,315 m
During 25-31 July the eruption that began on 17 July at Etna's Southeast
Crater continued at the same five eruptive fissures as the previous week. One
of the fissures was located on the NE flank and the other four on the S flank
at elevations of 2,950, 2,700, 2,500, and 2,100 m. During 24-26 July eruptive
activity declined at the 2,100 m fissure, but then intensified on 27 July to
reach the original level of Strombolian activity on the evening of 28 July. On
26 July modest lava emission occurred at the NE-flank fissure. At the 2,500 m
fissure, where the strongest explosive activity occurred, a change was noted
from the mostly phreatomagmatic eruptions that were prominent during the
previous week to more violent Strombolian explosions and lava effusion. After
lava began to flow from the 2,500 m fissure on 25 July, a pyroclastic cone
began to grow around three of the vents and by 30 July the cone was ~100 m
high. At the 2,950 m fissure (near the base of Southeast Crater) and 2,700 m
fissure lava emission and mild explosive activity continued.
On 26 July lava from the 2,500 m elevation fissure continued to flow towards
Rifugio Sapienza tourist complex, and as of 31 July a cable car base station
and a small tourist shop had been destroyed by lava that surpassed constructed
earth barriers. Lava continued to flow from the lower vents of the 2,100 m
fissure in the direction of the town of Nicolosi (~15 km SSE of the volcano),
but it was no longer considered a significant threat to the town.
Near-continuous ashfall occurred S of the volcano, including in the town of
Catania, ~25 km SSE of the volcano. The international Fontanarossa airport in
Catania was closed repeatedly on 29 and 30 July due to ash on the runways. The
Toulouse VAAC reported that ash clouds were occasionally visible on the Sistema
Poseidon web cam and satellite imagery, with the highest cloud rising ~5.5 km
above the volcano.
Background. Mount Etna, towering above Catania, Sicily's second largest city,
has one of the world's longest documented records of historical volcanism,
dating back to 1500 BC. Historical lava flows cover much of the surface of
this massive basaltic stratovolcano, the highest and most voluminous in Italy.
Two styles of eruptive activity typically occur at Etna. Persistent explosive
eruptions, sometimes with minor lava emissions, take place from one or more of
the three prominent summit craters: Central Crater, Northeast Crater, and
Southeast Crater. Flank eruptions, typically with higher effusion rates, occur
less frequently and originate from fissures that open progressively downward
from near the summit. A period of more intense intermittent explosive
eruptions from Etna's summit craters began in 1995.
Sources: Italy's Volcanoes , http://www.geo.mtu.edu/~boris/ETNA_news.html,
Charles Rivihre's web site
http://perso.club-internet.fr/rivierec/juillet_2001.htm,
Sistema Poseidon, http://www.poseidon.nti.it/,
Toulouse VAAC http://www.ssd.noaa.gov/VAAC/OTH/FR/messages.html,
Reuters http://news.excite.com/news/r/010727/08/international-italy-etna-dc,
Associated Press 30/7
http://www.washingtonpost.com/wp-srv/aponline/20010730/aponline093021_000.htm,
Associated Press 31/7
http://dailynews.yahoo.com/h/ap/20010731/wl/italy_volcano_22.html
Etna Reports
http://www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm from the
monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.2570N, 123.6850E; summit elev. 2,462m
After the pyroclastic-flow producing eruptions on 26 July Mayon entered an
effusive eruptive phase. During 27-31 July lava flowed up to 3.75 km toward the
SE in the Bonga Gully, accompanied by numerous high-frequency short-duration
tremor events caused by rock fragments detaching from the newly deposited lava
flow. Incandescence was visible at the crater, and thick steam plumes and
occasional short-lived ash emissions were seen. SO2 emission rates were high,
with a maximum of 9,900 metric tons measured on 31 July, which was well above
the baseline value of 500 metric tons/day. Due to the possibility of further
explosions, Alert Level 5 (the highest level) remained in effect. According to
news reports, on 31 July officials allowed residents who live outside of the
7-km danger zone to return to their homes.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462 m
above the Albay Gulf, is the Philippines' most active volcano. The structurally
simple volcano has steep upper slopes that average 35-400 and is capped by a
small summit crater. The historical eruptions of this basaltic-andesitic
volcano date back to 1616 and range from Strombolian to basaltic Plinian.
Eruptions occur predominately from the central conduit and have also produced
lava flows that travel far down the flanks. Pyroclastic flows and mudflows have
commonly swept down many of the approximately 40 ravines that radiate from the
summit and have often devastated populated lowland areas. Mayon's most violent
eruption, in 1814, killed more than 1,200 people and devastated several towns.
Eruptions that began in February 2000 led PHIVOLCS to recommend on 23 February
the evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Sources: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Associated Press
http://dailynews.yahoo.com/h/ap/20010731/wl/philippines_volcano_11.html,
Reuters
http://dailynews.yahoo.com/h/nm/20010730/sc/philippines_volcano_dc_5.html
Mayon Reports
http://www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from the
monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.6530N, 161.3600E; summit elev. 3,283m
During the week seismic activity remained above background levels, with many
small earthquakes occurring within the volcano's edifice and many different
seismic signals (explosion, avalanche, collapse) recorded locally.
Gas-and-steam plumes were observed from Klyuchi town and the highest cloud rose
to 2 km above the lava dome. One- to three-pixel anomalies were occasionally
visible on AVHRR imagery near the SW flank of the volcano. The volcano remained
at Concern Color Code Orange
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group and
forms one of Kamchatka's largest and most active volcanoes. The currently
active Molodoy Shiveluch lava-dome complex was constructed during the Holocene
within a large horseshoe-shaped caldera formed by collapse of the massive
late-Pleistocene Strary Shiveluch volcano. At least 60 large eruptions of
Shiveluch have occurred during the Holocene, making it the most vigorous
andesitic volcano of the Kuril-Kamchatka arc. Frequent collapses of lava-dome
complexes, most recently in 1964, have produced large debris avalanches whose
deposits cover much of the floor of the breached caldera. During the 1990s,
intermittent explosive eruptions took place from a new lava dome that began
growing in 1980. The largest historical eruptions from Shiveluch occurred in
1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm from
the monthly Bulletin of the Global Volcanism Network
SOUFRIHRE HILLS Montserrat, West Indies 16.720N, 62.180W; summit elev. 1,030m;
All times are local (= UTC 4 hours)
On 29 July ash from Soufrihre Hills drifted W, leaving deposits as far away as
San Juan, Puerto Rico, 450 km to the WNW. The Washington VAAC issued an
advisory on 27 July stating that a steady stream of ash was emitted from the
volcano through the evening, rising to 800 m. There was also a persistent,
strong hot spot over the volcano's summit visible in satellite imagery.
According to MVO, the amount of ash emitted from the volcano increased during
27 July through 29 July, and seismic activity rose on 29 July. Beginning at
1500 on 29 July heavy rainfall mixed with ash deposits and generated lahars
that flowed NW down the Belham River. The lava dome that had been growing in
the summit region of the volcano during recent years partially collapsed,
generating pyroclastic flows that traveled down the E flank of the volcano and
entered the sea. Shortly after 1700 observers reported seeing pyroclastic flows
and a continuous dense plume of ash that drifted to the W. Dense meteorological
clouds, associated with a tropical wave, crossed the island and prohibited ash
cloud detection in satellite imagery or ground confirmation of the height of
the ash cloud. MVO reported that the large amount of ash that was being vented
from the volcano rose to below 6 km. By midnight seismic and pyroclastic flow
activity returned to low levels. The next day AVHRR imagery showed possible ash
in an area W of Montserrat and SE of Puerto Rico. The position of the cloud
correlated with ground observations of ash and haze from Christiansted, St.
Croix.
There were reports of substantial ashfall and sporadic falling of stones in
the Montserrat residential areas of Salem and Olveston in the N part of the
island. Ash also fell in the US and British Virgin Islands, Roosevelt Roads
(Puerto Rico), Christiansted (St. Croix), and as far as 450 km away from the
volcano in San Juan (Puerto Rico). The ashfall in San Juan and the surrounding
area led to the closing of the San Juan International Airport on 30 July. The
airport reopened the next day.
Background. The complex andesitic Soufrihre Hills volcano occupies the southern
half of the island of Montserrat. The summit area consists primarily of a
series of lava domes emplaced along an ESE-trending zone. Non-eruptive seismic
swarms occurred at 30-year intervals in the 20th century, but the first
well-documented historical eruption on Montserrat did not take place until
1995. Long-term small-to-moderate ash eruptions were accompanied by lava dome
growth and pyroclastic flows that forced evacuation of the southern half of the
island and ultimately destroyed the capital city of Plymouth, causing severe
social and economic disruption. The volcano is currently in a period of new
dome growth.
Source: Montserrat Volcano Observatory http://www.mvo.ms/,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html, Associated Press
http://news.excite.com/news/ap/010730/18/int-italy-volcano, Reuters
http://biz.yahoo.com/rf/010731/n31163590.html
Soufrihre Hills Reports
http://www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
KIKAI [SATSUMA-IWO-JIMA] Ryukyu Islands, Japan 30.780N, 130.280E; summit elev.
717 m
Continuous volcanic tremor was recorded at Satsuma-Iwo-jima during 20 to at
least 23 July. A seismometer about 700 m SW of Iwo-dake crater recorded 50-100
earthquakes daily, in comparison to 30-90 earthquakes recorded daily during
December 2000 and March 2001. Small amounts of volcanic tremor were also
occasionally recorded. The Iwo-jima Branch of the Mishima Village Office
reported that ash fell during 19-21 July. Faint ashfall and small volcanic
tremor had occurred since December 2000.
Background. Kikai is a mostly submerged, 19-km-wide caldera near the northern
end of the Ryukyu Islands south of Kyushu. Kikai was the source of one of the
world's largest Holocene eruptions about 6300 years ago. Pyroclastic flows
traveled across the sea for a total distance of 100 km to southern Kyushu, and
ashfall reached the northernmost Japanese island of Hokkaido. The eruption
devastated southern and central Kyushu, which remained uninhabited for several
centuries. Historical eruptions have occurred in the 20th century at or near
Tokara-Iwo-Jima (also known as Satsuma-Iwo-jima), a small 3 x 6 km island
forming part of the NW caldera rim. Showa-Iwo-jima (also known as
Iwo-jima-Shinto), a small island 2 km east of Tokara-Iwo-jima, was formed
during submarine eruptions in 1934 and 1935. Explosive eruptions have occurred
during the past few decades from Iwo-dake, a rhyolitic lava dome at the eastern
end of Tokara-Iwo-jima.
Source: Volcano Research Center
http://hakone.eri.u-tokyo.ac.jp/vrc/erup/satsuma_iwo.html
Satsuma-Iwo-jima Reports
http://www.volcano.si.edu/gvp/volcano/region08/kyushu/kikai/var.htm from the
monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.430N, 155.290W; summit elev. 1,222 m
During the week small-to-moderate levels of lava entered the ocean at the E
Kupapa`u entry. During 26-28 July a stream of `a`a lava continuously advanced
down the Pulama pali scarp to the coastal flat on the E side of the current
lava flow field. Generally, weak, rather steady tremor and a few related
long-period earthquakes continued beneath Kilauea's caldera. Near Pu`u `O`o
the tremor also became weak and continuous. Elsewhere, seismicity was at normal
levels. Tiltmeters across the volcano indicated no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the island
of Hawaii, is one of the world's most active volcanoes. Historically its
eruptions originate primarily from the summit caldera or along one of the
lengthy E and SW rift zones that extend from the caldera to the sea. The latest
Kilauea eruption began in January 1983 along the E rift zone. The Pu`u
`O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive episode.
Since 1986, flows have traveled 11-12 km from the vents to the sea, paving
about 80 km2 of land on the S flank of Kilauea and building 205 hectares of new
land. Intensive monitoring and field research by staff of the US Geological
Survey's Hawaiian Volcano Observatory, established in 1912, make Kilauea one
of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http://www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm from
the monthly Bulletin of the Global Volcanism Network
POPOCATIPETL Mixico 19.020N, 98.620W; summit elev. 5,426 m; All times are
local (= - 5 hours)
Several small-to-moderate sized emissions occurred at Popocatipetl that were
mainly composed of steam, gas, and small amounts of ash. The Washington VAAC
received a pilot report on 24 July at 1100 of an ash cloud ~5.5 km above the
volcano drifting to the W. On 23 July CENAPRED reduced the Alert Level from
Yellow Phase III to Phase II because volcanic activity was at lower levels than
it was in December 2000 when the Alert Level was originally raised.
Background. Popocatipetl, whose name is the Aztec word for smoking mountain,
towers to 5,426 m 70 km SE of Mixico City and is North America's second highest
volcano. Frequent historical eruptions have been recorded since the beginning
of the Spanish colonial era. A small eruption on 21 December 1994 ended five
decades of quiescence. Since 1996 small lava domes have incrementally been
constructed within the summit crater and destroyed by explosive eruptions.
Intermittent small-to-moderate gas-and-ash eruptions have continued,
occasionally producing ashfall in neighboring towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Sources: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Popocatipetl Reports
http://www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html from the
monthly Bulletin of the Global Volcanism Network
SUWANOSE-JIMA Ryukyu Islands, Japan 29.530N, 129.720E; summit elev. 799m;
All times are local (= GMT + 9 hours)
Volcanic tremor was detected near Suwanose-jima's On-take (Otake) crater
beginning on 25 July at 2200 until at least 26 July. JMA reported that an
eruption on 26 July at 1430 produced a volcanic plume that rose to 1.3 km above
the crater and drifted to the S. That day seismometers ~2 km SW of the crater
recorded explosions at 0501, 0558, 0935, and 1055. According to the
Suwanose-jima Branch of the Toshima Village Office, ash fell the morning of 26
July.
Background. The 8-km-long, spindle-shaped island of Suwanose-jima in the
northern Ryukyu Islands is occupied by a stratovolcano with two historically
active summit craters. Only about 50 persons live on the sparsely populated
island. The summit of the volcano is truncated by a large breached crater
extending to the sea on the E flank that was formed by edifice collapse.
Suwanose-jima, one of Japan's most frequently active volcanoes, was in a state
of intermittent Strombolian activity from On-take (also called Otake), the NE
summit crater, that began in 1949 and lasted nearly a half century. The
largest historical eruption took place in 1813-14, when thick scoria deposits
blanketed residential areas, after which the island was uninhabited for about
70 years. The SW crater produced lava flows that reached the western coast in
1813, and lava flows reached the eastern coast of the island in 1884.
Source: Volcano Research Center-Earthquake Research Institute (University of
Tokyo) http://hakone.eri.u-tokyo.ac.jp/vrc/erup/suwa.html
Suwanose-jima Reports
http://www.volcano.si.edu/gvp/volcano/region08/kyushu/suwanose/var.htm from
the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.470S, 78.440W; summit elev. 5,023 m; All times are local
(= UTC 5 hours)
Several small-to-moderate eruptions occurred at Tungurahua during the week.
The Washington VAAC reported that the highest ash cloud was produced from an
eruption on 25 July at 0604. The ash cloud rose ~ 9 km a.s.l. and drifted to
the SW.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador's capital city,
and is one of Ecuador's most active volcanoes. Historical eruptions have been
restricted to the summit crater. They have been accompanied by strong
explosions and sometimes by pyroclastic flows and lava flows that reached
populated areas at the volcano's base. The last major eruption took place from
1916 to 1918, although minor activity continued until 1925. The latest eruption
began in October 1999 and prompted an initial evacuation of the town of Baqos
on the N side of the volcano.
Sources: Instituto Geofmsico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http://www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm from
the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 539 of 997: Marcia (MarciaH) * Fri, Aug 3, 2001 (16:40) * 113 lines
HVO and AVO Volcano Updates
U.S. Geological Survey
Hawaiian Volcano Observatory
PO Box 51, Hawaii National Park, HI 96718
Phone (808) 967-7328 FAX (808) 967-8890
(Hawaiian)Volcano Watch - August 2, 2001
Backyard steam indicates warmth but probably not volcanic
Every few months HVO receives a phone call from a concerned citizen
explaining that steam is billowing from a new hole in a yard or pasture. Is
this foretelling the start of an eruption?
Indeed, steam often does rise from the ground before lava comes out. We
have excitedly observed that happening several times as an erupting fissure
along Kilauea's east rift zone gradually lengthened by splitting open the
ground. The steam is generated by ground water that is heated just ahead of
rising magma. Other gases may also be emitted in advance of a growing
fissure, methane being the most common. Methane is also released from the
ground, sometimes explosively, near the edges of lava flows moving through
vegetation.
In most cases, however, the new steam reported on residential or farm
land is not related to anything volcanic. Instead, the steam, sometimes
accompanied by methane, records rotting vegetation just below the ground
surface.
Many of you are familiar with compost piles and with the precautions that
must be taken to prevent them from smoldering and even bursting into flame.
The same thing can occur in areas of landfill, land clearing, or even
completely naturally.
Dead vegetation rots, and some of the chemical reactions that take place
release heat. With proper ventilation, the heat is dissipated to the air
without any problem. A dense mat of rotting vegetation may, however, trap
the heat. That is why it is always a good idea to keep your compost pile
rather loose and airy.
Many of the reports of new steaming holes come from locations 200-300 m
(a few hundred feet) or more about sea level, where the mornings are cool.
Warm air escaping from the ground may condense to steam on such mornings
and become visible to onlookers.
Many of the reports also come from areas that were cleared by bulldozers
or other heavy equipment that shoved vegetation into holes in the ground
surface. The buried vegetable debris forms a kind of compost pile, which
rots and heats. Most of the heat is lost passively, but if the pile is
dense, or if it is trapped within a small lava tube, tree mold, or natural
ground crack, it may build up and become quite warm.
Only rarely does a fire result. Noticeable amounts of steam can be
generated, however, if the ground surface is broken by collapse of weak
soil, cave-in of a lava tube, or small explosions resulting from increased
pressure. More often, the pressure simply drives the warm, light gas upward
through pores in the soil. In any case, there may be enough steam to be
quite evident on cool or humid mornings and days.
There are several ways that we can check a caller's observations to see
whether an eruption might be coming. The seismic monitoring done by HVO is
the first thing we fall back on. Lacking seismicity in the general area of
the report, it is very unlikely that magma is nearing the surface, either
rapidly or slowly. Check our website, http://hvo.wr.usgs.gov, for
up-to-date seismic information for your part of the island.
Secondly, we consider the location. Is the steam coming from one of the
rift zones or is it on the flank of one of the island's volcanoes far from
most volcanic vents?
Thirdly, we ask the caller to describe the nature of the steam source; is
it a hole, a long crack freshly cutting the ground surface, a skylight in
the roof of a small tube, etc. Of these possibilities, only the new long
crack would be possible cause for concern.
Finally, we can visit the site and take samples to analyze for volcanic
gas if necessary.
Backyard steam is mostly benign and unlikely to be a harbinger of
something volcanic without other evidence of unrest.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u `O`o
vent during the past week. Lava moves away from the vent toward the ocean
in a network of tubes and descends Pulama pali in two separate areas.
Breakouts from the tube system above Pulama pali fed ephemeral flows on the
pali. Small surface flows, primarily ooze-outs from inflated areas in the
coastal flats, are occasionally observed. Lava continued to enter the
ocean in the area east of Kupapa`u throughout the week. The public is
reminded that the ocean entry areas are extremely hazardous, with
explosions accompanying frequent collapses of the new land. The steam cloud
is extremely hot, highly acidic, and laced with glass particles. Swimming
in the area can be a blistering or even deadly experience.
One earthquake was reported felt during the week ending on August 2,
2001. A resident of Papa`aloa felt an earthquake at 11 minutes after
midnight on July 29. The magnitude-2.7 temblor was located 9 km (5.4 mi)
west of Honoka`a at a depth of 35.84 km (21.5 mi). There were no
earthquakes from Lo`ihi Volcano during the past week.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, August 03, 2001 11:00 AM ADT (1900 UTC)
ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior without being considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
in color code GREEN. All are at or near normal levels of background
seismicity. AVO did not detect ash plumes or significant elevated surface
temperatures in the vicinity of any volcano.
Abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of Alaska's volcanoes (907) 786-7478
Topic 2 of 99 [Geo]: Vulcanism
Response 540 of 997: Marcia (MarciaH) * Fri, Aug 3, 2001 (16:51) * 1 lines
Those of you who bothered to read the above Kilauea Volcano update will note about exlosions far from the lava flows. I can tell you first hand about that. I was hiking with friends and son when a National Park vehicle came by. I ducked onto the dirt berm at the edge of the pavement, and the Ranger told me to get back onto the roadway. I looked at him oddly because I knew better than to step in cracks or hot lava. Suddenly, directly in front of me, an explosion flung dirt and small rocks about 2 meters into the air with a very loud noise. I did not walk on the dirt berm again, and I never will forget my near miss. Other than missed heart-beats, I got away with my transgression unscathed.
Topic 2 of 99 [Geo]: Vulcanism
Response 541 of 997: Marcia (MarciaH) * Sat, Aug 4, 2001 (18:40) * 37 lines
VOLCANIC ASH ADVISORY
ISSUED: 2001AUG04/0915Z VAAC: WASHINGTON
.
VOLCANO: SOUFRIERE HILLS 1600-05
LOCATION: 1643N 6211W AREA: CARIBBEAN
.
SUMMIT ELEVATION: 3000 FT (915 M)
.
ADVISORY NUMBER: 2001/198
.
INFORMATION SOURCE: GOES-8 INFRARED AND MULTISPECTRAL IMAGERY.
.
ERUPTION DETAILS: MINOR ERUPTION SEEN AT AROUND 0700Z.
.
DETAILS OF ASH CLOUD: GOES INFRARED LOOPS INDICATE A MINOR ASH
ERUPTION FROM SOUFRIERE HILLS. ASH IS OBSERVED GOING IN TWO SEPARATE
DIRECTIONS INDICATING A MULTI LEVEL ERUPTION. THE FIRST ASH CLOUD IS
MOVING NORTHWEST AT 5 TO 10 KNOTS. AT 0815Z IT IS OBSERVED TO BE 38
KM (21 NMI) NORTHWEST FROM THE VOLCANO TO POINT 1650N6231W. THE
SECOND CLOUD IS MOVING NORTHEAST AND IS OBSERVED TO BE 31 KM (17
NMI) FROM THE VOLCANO TO POINT 1652N6156W. THE NORTHWEST CLOUD IS
ESTIMATED TO BE AT FL150 WHILE THE NORTHEAST CLOUD IS ESTIMATED TO
BE AT FL320.
.
TRAJECTORY: UPPER AIR PATTERNS SUGGEST ASH FROM FL100 TO FL200 TO BE
MOVING NORTHWEST AT 5 TO 10 KNOTS WHILE ASH ABOVE FL320 TO MOVE
NORTHEAST AT 10 KNOTS.
.
OUTLOOK: SEE SIGMETS AND VAFTAD.
.
THE NEXT ADVISORY WILL BE ISSUED BY 04/1500Z.
.
REAL TIME SATELLITE IMAGERY AND VOLCANIC ASH ADVISORIES OFTEN
ACCOMPANIED BY A MAP DEPICTING ASH LOCATION ARE AVAILABLE AT
INTERNET URL ADDRESS
HTTP://WWW.SSD.NOAA.GOV/VAAC/WASHINGTON.HTML
Topic 2 of 99 [Geo]: Vulcanism
Response 542 of 997: Marcia (MarciaH) * Sat, Aug 4, 2001 (18:42) * 1 lines
The above link should read http://www.ssd.noaa.gov/VAAC/washington.html
Topic 2 of 99 [Geo]: Vulcanism
Response 543 of 997: horrible horace (horrible) * Sat, Aug 4, 2001 (18:55) * 1 lines
Git on that messenger Lady ,'fore il horace gits cut of agin@
Topic 2 of 99 [Geo]: Vulcanism
Response 544 of 997: Marcia (MarciaH) * Sat, Aug 4, 2001 (20:03) * 1 lines
I got on. We spoke. Half a world away, with fingers. You are not all that wordy tonight, Horace. You have spurned my attentions!
Topic 2 of 99 [Geo]: Vulcanism
Response 545 of 997: Cheryl (CherylB) * Mon, Aug 6, 2001 (18:57) * 1 lines
Hawaii the result of a cosmic collision. The suggestion that Mme. Pele is an alien. No, she won't be amused.
Topic 2 of 99 [Geo]: Vulcanism
Response 546 of 997: Marcia (MarciaH) * Mon, Aug 13, 2001 (17:10) * 1 lines
I would be very careful what I called Pele, other than the Hawaiian Goddess of the Volcanoes. Madame is also acceptable. Like Queen Victoria, I think She would NOT be amused by mere mortals being disrespectful. It is a novel idea, thugh about the meteors... I think it will get little support from the science community!
Topic 2 of 99 [Geo]: Vulcanism
Response 547 of 997: Marcia (MarciaH) * Mon, Aug 13, 2001 (17:13) * 15 lines
Borrowed from http://clubs.yahoo.com/clubs/worldvolcanism
Southern Vancouver Island sits on the Cascadia subduction zone, where the eastern edge of the Juan de Fuca Plate moves
under the North American Plate and eventually melts. Some of the resulting magma has formed the Cascade Volcanoes (CV).
The Meagher Mountain Complex is the northernmost CV and lies about 150 kilometers north of Vancouver, British
Columbia. Mt. Garibaldi is about 80 kilometers north of Vancouver.
But the most prominent CV to residents of southwestern British Columbia is Mt. Baker in northern Washington State. Its
summit stands almost 3.3 kilometers above sea level and is heavily covered with ice. Its lavas are andesite (in some cases
almost silicic enough to be called dacite).
The most heavily glaciated CV of all is Mt. Rainier (4,392 meters). This mountain is so big that it is sometimes visible from
my home almost 200 kilometers away. Its lavas are similar to Mt. Baker's with some SiO2 percentages in the low sixties.
If either mountain erupts there could be devastating pyroclastic flows, plus floodwaters from melting glaciers and
snowfields.
* Thanks, Tony *
Topic 2 of 99 [Geo]: Vulcanism
Response 548 of 997: Marcia (MarciaH) * Mon, Aug 13, 2001 (20:02) * 24 lines
*****************
Etna photos
*****************
From: tom pfeiffer
Dear volcanophiles,
2 new pages with photos of Etna's recent flank
eruption from 23-30 July are now available on
the Santorini Decade Volcano website:
http://www.geo.aau.dk/palstrat/tom/santorini_homepage/volcanoes/etna0701_1.htm
http://www.geo.aau.dk/palstrat/tom/santorini_homepage/volcanoes/etna0701_2.htm
Tom Pfeiffer
Geologisk Institut
Universitet Aarhus
Denmark
tpfeif@geo.aau.dk
Topic 2 of 99 [Geo]: Vulcanism
Response 549 of 997: Marcia (MarciaH) * Mon, Aug 13, 2001 (20:18) * 59 lines
****************************
Etna satellite images
****************************
From: JPLNews@jpl.nasa.gov
(forwarded by Claude Desgroseilliers )
MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov
Contact: Enrico Piazza (818) 354-0478
IMAGE ADVISORY
August 3, 2001
ETNA VOLCANO: UPDATE FROM SPACE
Mount Etna, Europe's most active volcano, continues to spill rivers of
lava
following a July 17 eruption. The recent activity of the 3,315-meter
(10,876-foot) high volcano can be seen in two images taken Sunday,
July 29
by the Advanced Spaceborne Thermal Emission and Reflection Radiometer
on
NASA's Terra spacecraft.
The images are available at:
http://www.jpl.nasa.gov/images/earth/volcano .
One image shows the lava advancing toward the town of Nicolosi on the
Italian island of Sicily. While the last two days have been relatively
calm, a river of lava is about 4 kilometers (2.5 miles) away from the
town.
Thick ash clouds caused airport closures and forced residents in the
nearby
city of Catania to use umbrellas while walking outside. The other
image
shows a large sulfur dioxide plume coming from the summit of the
volcano.
More information on Advanced Spaceborne Thermal Emission and
Reflection
Radiometer is available at:
http://asterweb.jpl.nasa.gov.
The Terra spacecraft, the flagship of a fleet of satellites dedicated
to
understanding our global environment, is part of NASA's Earth Sciences
Enterprise, a long-term research program dedicated to understanding
how
human-induced and natural changes affect our world. JPL is managed by
the
California Institute of Technology in Pasadena.
Topic 2 of 99 [Geo]: Vulcanism
Response 550 of 997: Marcia (MarciaH) * Wed, Aug 15, 2001 (18:00) * 16 lines
***********************************
'Volcanic Clouds' discussion list
***********************************
From: Andrew Tupper
Following a successful workshop at Michigan Technological University last
week, an unmoderated E-mail list has been formed specifically for
discussion about remote sensing of volcanic clouds.
The list 'home page' is at http://groups.yahoo.com/group/volcanicclouds .
Subscription requests to: volcanicclouds-subscribe@yahoogroups.com
Please redistribute this message as appropriate.
Andrew Tupper
Darwin Volcanic Ash Advisory Centre.
Topic 2 of 99 [Geo]: Vulcanism
Response 551 of 997: Marcia (MarciaH) * Wed, Aug 15, 2001 (18:08) * 139 lines
************************************
KVERT Information Release 50-01,
August 9, 2001
************************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 50-01
Thursday, August 09, 2001, 10:55 KDT (21:55 UTC)
The following Release was received by the Alaska Volcano Observatory
via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are Kamchatkan Daylight Time, 21 hours ahead of ADT.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS RED.
Seismic activity was above background on August 7-8. Weak shallow
earthquakes within the volcano's edifice were registered. Many weak local
seismic events (probable dome collapses and avalanches) were recorded. From
11:28 KDT on August 07(22:28 UTC on August 06) until 13:00 KDT on August 07
(24:00 UTC on August 06) spasmodic volcanic tremor up to 11.7x10-6 mps was
recorded. From 13:00 KDT (00:00 UTC) until 14:10 KDT (01:00 UTC) on August
07 the tremor amplitude up to 1.0x10-6 mps was registered. After 14:00 KDT
(01:00 UTC) on August 07 spasmodic volcanic tremor again decreased.
Observers in Klyuchi town reported that at 11:28 KDT on August 07 (at 22:28
UTC on August 06) an ash plume rose 5,000 m ASL (16,500 ft. ASL) above the
volcano and extended to the east-southeast. At 12:15 KDT on August 07 (at
23:15 UTC on August 06) the ash plume rose 10,000 m ASL (33,000 ft ASL) and
extended to the east-southeast.
According to visual data from Kozirevsk village, at 12:15 KDT on August 07
(at 23:15 UTC on August 06) an ash plume rose 2,000-2,500 m above the dome
and extended to the southwest. At 13:00 KDT (at 00:00 UTC) on August 07 a
gas-ash plume rose 2,000 m above the dome and extended southwest 40 km.
Observers in Kronoki seismic station reported that on August 07 an ash fall
was recorded (50 gr. of the ash per square m).
At 17:02 KDT (04:02 UTC) on August 07 an ash plume from Bezymianny was
observed in a satellite image. The plume was approximately 200 km long and
100 km wide and was heading due south.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
************************************
KVERT Information Release 51-01,
August 10, 2001
************************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 51-01
Friday, August 10, 2001, 13:45 KDT (00:45 UTC)
The following Release was received by the Alaska Volcano Observatory
via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity was above background this past week. Many small
earthquakes within the volcano's edifice and local seismic signals
(explosions, avalanches, collapses) were recorded. One MI>=2 earthquake was
registered. Continuous spasmodic volcanic tremor amplitude was, on average,
6.0-6.3x10-6 mps the past week.
Observers in Klyuchi reported that at 15:00 KDT (at 02:00 UTC) on August 08
a gas and steam plume rose 200 m above the dome (2,600 m, 8,600 ft. ASL).
At other times, clouds obscured the volcano.
An AVHRR satellite image showed a 4-pixel thermal anomaly of 49.5 degrees C
near the active dome area at 18:08 KDT (05:08 UTC) on August 04. A group of
warm pixels was also observed trending to the southeast (hot material or a
possible steam plume). Two pixels near sensor saturation (49.6 degrees C)
were seen near the southwest flank of volcano at 17:51 KDT (04:51 UTC) on
August 06. A 2-pixel thermal anomaly was seen at 06:52 KDT on August 09
(17:52 UTC on August 08) with a maximum temperature of 20 degrees C.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background on August 06 and 08, but was above
background levels at all other times. Twelve MI>=1.7 and fourteen MI>=2
earthquakes were registered. Weak intermittent spasmodic volcanic tremor
was recorded on August 03-06. On August 03 and 07, shallow earthquakes
within the volcano's edifice were recorded. On August 06-08, gas and steam
plumes rose 50 - 100 m above the crater (4,800-4,850 m, 15,800-16,000 ft.
ASL). At other times, clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS YELLOW.
Seismic activity was at background on August 03-05, but was above
background levels at all other times. Weak shallow earthquakes within the
volcano's edifice and many weak, local seismic events (probable collapses
and avalanches) were registered on August 06-08. At other times, clouds
obscured the volcano. From 11:28 KDT on August 07 (22:28 UTC on August 06)
until 13:00 KDT on August 07 (24:00 UTC on August 06), spasmodic volcanic
tremor up to 11.7x10-6 mps was recorded. From 13:00 KDT (00:00 UTC) until
14:10 KDT (01:00 UTC) on August 07, tremor amplitude up to 1.0x10-6 mps was
registered. After 14:00 KDT (01:00 UTC) on August 07 spasmodic volcanic
tremor again decreased.
At 11:28 KDT on August 07 (22:28 UTC on August 06), an explosive eruption
began. Observers in Klyuchi town reported that at 11:28 KDT on August 07
(22:28 UTC on August 06) an ash plume rose 5,000 m ASL (16,500 ft. ASL)
above the volcano and extended to the east-southeast. At 12:15 KDT on
August 07 (at 23:15 UTC on August 06), the ash plume rose 10,000 m ASL
(33,000 ft. ASL) and extended to the east-southeast.
According to visual data from Kozirevsk village, at 12:15 KDT on August 07
(at 23:15 UTC on August 06), an ash plume rose 2,000-2,500 m above the dome
(4,900-5,400 m, 16,200-17,800 ft. ASL) and extended to the southwest. At
13:00 KDT (at 00:00 UTC) on August 07, a gas-ash plume rose 2,000 m above
the dome (4,900 m, 16,200 ft. ASL) and extended southwest 40 km. Observers
in Kronoki seismic station reported an ash fall (50 g per square m) on
August 07.
An AVHRR satellite image showed a 3-pixel thermal anomaly (49.5 degrees C)
with the fourth pixel at 46.2 degrees C at 17:51 KDT (at 04:51 UTC) on
August 06. A possible steam plume was also observed trending to the
southeast. At 17:02 KDT (04:02 UTC) on August 07, an ash plume from
Bezymianny was observed in a satellite image. The plume was centered off
the eastern coast of Kamchatka about 200 km south of Kronotsky. The plume
was approximately 200 km long and 100 km wide and was heading due south. A
3-pixel thermal anomaly with a maximum temperature of 28 degrees C was
observed at 06:52 KDT on August 09 (17:52 UTC on August 08). This thermal
anomaly showed that a viscous lava flow had formed at the dome of volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
Seismic activity was at background levels. On August 03-04, weak spasmodic
tremor was registered. On August 07-08, both volcanoes appeared quiet. At
other times, clouds obscured the volcanoes.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Topic 2 of 99 [Geo]: Vulcanism
Response 552 of 997: Marcia (MarciaH) * Wed, Aug 15, 2001 (18:47) * 14 lines
********************************
Info on Mt Rainier debris flow
********************************
Around 10 pm, last night, a "glacier outburst" took place from the Van
Trump Glacier into the Van Trump Creek, which drains into the Nisqually
River. This appears to be the result of unusually hot Summer temperatures
melting glacial ice, which ponded under the glacier, and not from thermal
activity. Luckily, the rivers are low right now due to the Summer drought,
and not injuries or damage have been reported.
From:
http://seattletimes.nwsource.com/html/localnews/134329746_rainier15m.html
Topic 2 of 99 [Geo]: Vulcanism
Response 553 of 997: Marcia (MarciaH) * Wed, Aug 15, 2001 (18:54) * 301 lines
GVP/USGS Weekly Volcanic Activity Report 8-14 August 2001
http://www.volcano.si.edu/gvp/usgs/index.htm
New Activity/Unrest: | Hakone, Japan | Mayon, Philippines |
Ongoing Activity: | Bezymianny, Russia | Etna, Italy | Kilauea, USA |
Pinatubo, Philippines | Popocatépetl, México | Shiveluch, Russia |
Soufrière Hills, Montserrat | Tungurahua, Ecuador | Villarrica, Chile |
New Activity
HAKONE Honshu, Japan 35.22°N, 139.02°E; summit elev. 1,438 m
Elevated seismicity had been recorded at Hakone during June 2001 to at
least 8 August. The seismicity was associated with a small amount of
inflation that was centered at the volcano. Earthquake hypocenters occurred
at depths less than 5 km beneath the volcano. A small swarm was also
recorded under the northern end of the Ashino-ko (caldera lake). JMA noted
that the change in activity might not be a precursor to an eruption since
similar activity has occurred in the past that was not followed by an
eruption.
Background. Hakone volcano is truncated by two calderas, the largest of
which is 10 x 11 km wide. The calderas were formed as a result of two major
explosive eruptions about 180,000 and 49,000-60,000 years ago. Post-caldera
volcanism has consisted primarily of the growth of a half dozen lava domes
along a SW-NE trend cutting through the center of the calderas. The largest
of these, Kami-yama, forms the high point of Hakone. The calderas are
breached to the E. Blockage of the Haya-kawa river about 3,000 years ago
created Lake Ashi, which along with major thermal areas in the caldera,
constitutes a major resort area SW of Tokyo. The latest eruption took place
about 3,000 years ago, although seismic swarms have occurred frequently
during the 20th century.
Source: Volcano Research Center
http://hakone.eri.u-tokyo.ac.jp/vrc/erup/hakone.html
Hakone Reports
http://www.volcano.si.edu/gvp/volcano/region08/honshu/hakone/var.htm
from the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
A decline in seismic and volcanic activity occurred at Mayon beginning on 8
August. The level of seismicity remained above background, but declined to
non-eruptive conditions. The volcano’s edifice was less inflated than
during previous weeks. Continuing low-level activity in the crater area
produced a high SO2 emission rate and visible incandescence. On 9 August
PHIVOLCS decreased the Alert Level from 5 (the highest) to 4. The
6-km-radius Permanent Danger Zone and the 7-km-radius Extended Danger Zone
remained in effect.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Sources: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Inquirer News Service http://www.inq7.net/reg/2001/aug/08/reg_1-1.htm
Mayon Reports
http://www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from
the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
BEZYMIANNY Kamchatka Peninsula, Russia 55.98°N, 160.59°E; summit elev.
2,882 m; All times are local (= UTTC + 12 hours)
Volcanic activity decreased after an eruption at Bezymianny on 7 August at
1128. Later in the day, smaller explosions produced ash clouds that rose to
2 km above the dome. Seismic activity was above background levels on 7-8
August, with many small earthquakes occurring within the volcano's edifice
and several different seismic signals (explosion, avalanche, collapse)
recorded locally. On 9 August a three-pixel thermal anomaly was visible on
satellite imagery. The anomaly represented a viscous lava flow that had
formed at the dome of the volcano. On 9 August the Concern Color Code <
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm> was reduced from
Red (the highest level) to Yellow and was further reduced on 10 August to
Green (the lowest level).
Background. Prior to its noted 1955-56 eruption, Bezymianny volcano had
been considered extinct. Three periods of intensified activity have
occurred during the past 3,000 years. The latest period, which was preceded
by a 1,000-year quiescence, began with the dramatic 1955-56 eruption. That
eruption, similar to the 1980 event at Mount St. Helens, produced a large
horseshoe-shaped crater that was formed by collapse of the summit and an
associated lateral blast. Subsequent episodic but ongoing lava-dome growth,
accompanied by intermittent explosive activity and pyroclastic flows, has
largely filled the 1956 crater.
Source: KVERT via the Alaska Volcano Observatory
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Bezymianny Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/bezymian/var.htm
from the monthly Bulletin of the Global Volcanism Network
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
As of 13 August lava flows appeared to cease advancing down the slopes of
Etna. Slight degassing occurred from many of the fissures and the rate of
SO2 emission was low in comparison to average values for the season.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Sources: Charles Rivière’s web site
http://perso.club-internet.fr/rivierec/aout_2001.htm,
BBC News
http://news.bbc.co.uk/hi/english/world/europe/newsid_1480000/1480709.stm
Etna Reports
http://www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm from
the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Small amounts of lava continued to enter the ocean at the E Kupapa`u entry.
Surface lava flows were observed issuing from the eastern tube of the
current flow field. One of the lobes of lava reached ~1.1 km short of the
coast. Generally, weak, rather steady tremor and a few small earthquakes
continued beneath Kilauea's caldera. Near Pu`u `O`o, continuous tremor
occurred at weak-to-moderate levels. Tiltmeters across the volcano showed
no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http://www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
PINATUBO Luzon, Philippines 15.13°N, 120.35°E; summit elev. 1,486 m
Several news reports stated that rising water in Pinatubo’s crater is now
approaching dangerous levels. If the water exceeds the crater lip, it could
cause the crater to partially collapse and water could inundate the town of
Botolan. The town is 40 km NW of the volcano and has 46,000 residents. In
recent weeks the water surface has risen from ~6.4 to 5 m below the crater
lip. Scientists are worried that the intense rain during the current rainy
season will cause the water level to continue to rise. In the next few
weeks, with oversight by Philippine officials and geologists, local
residents will dig a 5-m notch in the side of the crater that will drain
the water away from inhabited areas.
Background. Prior to 1991 Pinatubo volcano was a relatively unknown,
heavily forested lava dome complex located 100 km NW of Manila with no
records of historical eruptions. The 1991 eruption, one of the world's
largest of the 20th century, ejected massive amounts of tephra and produced
voluminous pyroclastic flows, forming a small, 2.5-km-wide summit caldera
whose floor is now partially filled by a lake. Although the eruption caused
hundreds of fatalities and severe social and economic impact, successful
monitoring efforts greatly reduced the number of fatalities. Widespread
lahars that redistributed products of the 1991 eruption have continued to
cause severe disruption. At least six major eruptive periods, separated by
lengthy quiescence, have occurred from modern Pinatubo volcano during the
past 40,000 years. Most of these have produced major pyroclastic flows and
lahars that were even more extensive than in 1991.
Sources: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Reuters
http://dailynews.yahoo.com/h/nm/20010808/wl/philippines_volcano_dc_11.html,
Associated Press
http://dailynews.yahoo.com/h/ap/20010809/wl/philippines_mount_pinatubo_1.htm
l, Disaster Relief.org http://www.disasterrelief.org/Disasters/010810pinatubo/
Pinatubo Reports
http://www.volcano.si.edu/gvp/volcano/region07/luzon/pinatubo/var.htm
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC 5 hours)
The number of small emissions composed of steam, gas, and small amounts of
ash increased in comparison to the previous week. The Washington VAAC
reported an ash emission on 9 August at 2300 produced an ash cloud that
rose to 7.6 km a.s.l. According to CENAPRED, the increase in activity may
have been related to several days of intense rain in the area.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html
Popocatépetl Reports
http://www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev. 3,283 m
During the week seismic activity remained above background levels, with
many small earthquakes occurring within the volcano's edifice and several
different seismic signals (explosion, avalanche, collapse) recorded
locally. Small gas-and-steam plumes rose to 200 m above the dome. Thermal
anomalies were seen in several areas on satellite imagery. The volcano
remained at Concern Color Code Orange
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
During the week volcanic activity was low at Soufrière Hills. Small-scale
rockfalls and minor pyroclastic flows occurred mainly off of the sides of
the scar left after the partial dome collapse on 29 July. Like the previous
week, a new dome was seen growing within the scar.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvo.ms/
Soufrière Hills Reports
http://www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
Ongoing eruptions occurred at Tungurahua since at least 6 August at 0703,
sending steam-and-ash clouds to 7.5-11.6 km a.s.l. The ash clouds primarily
drifted towards the W. On 13 August three particularly strong emissions
occurred at about 0630, 1200, and 1315. Afterward, two distinct areas of
ash were visible in satellite imagery; one contained ash from the strong
emissions, rose to ~11.6 km a.s.l. and drifted to the E; the other ash
cloud was fed from continuous emissions and possibly rose to ~10 km a.s.l.
and drifted to the SW.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html,
Associated Press
http://dailynews.yahoo.com/h/ap/20010813/wl/ecuador_volcano_1.html
Tungurahua Reports
http://www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
VILLARRICA central Chile 39.42°S, 71.93°W; summit elev. 2,847 m
Volcanic activity at Villarrica was at relatively normal levels as of 9
August. The amount of incandescent lava decreased in comparison to the
amount observed during 19 and 22 July. Strong degassing occurred and
ejections of ash, lapilli, and volcanic bombs landed on the W to SW edge of
the crater.
Background. Villarrica, one of Chile's most active volcanoes, rises above
the lake and town of the same name. It is the westernmost of three large
stratovolcanoes that trend perpendicular to the Andean chain. A 6-km wide
caldera formed during the late Pleistocene, more than 0.9 million years
ago. A 2-km-wide postglacial caldera is located at the base of the
presently active, dominantly basaltic-to-andesitic cone at the NW margin of
the Pleistocene caldera. About 25 scoria cones dot Villarica's flanks.
Plinian eruptions and pyroclastic flows have been produced during the
Holocene from this dominantly basaltic volcano, but historical eruptions
have consisted largely of mild-to-moderate explosive activity with
occasional lava effusion. Lahars from the glacier-covered volcano have
damaged towns on its flanks.
Source: Villarrica Volcano Visual Surveillance Project http://www.povi.org/
Villarrica Reports
http://www.volcano.si.edu/gvp/volcano/region15/andes_c/villaric/var.htm
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 554 of 997: Marcia (MarciaH) * Fri, Aug 17, 2001 (14:47) * 18 lines
By Rob and borrowed from http://clubs.yahoo.com/clubs/worldvolcanism
The 118th anniversary of the great Krakatoa eruption, 1883 is on Monday August 27.
Krakatoa earnt it's fame by generating the worlds LOUDEST recorded
natural explosion. When the 3rd of 4 titanic explosions occurred at about
1000 hours local time, the residents of Rodgeruiz (sp??) Island, heard
artillery like explosions. The island is 4800km (3000mi)from the volcano
and no naval (suspected culprit at the time)was in progress. No wars of
any sort were being fought in the area.
I will write a novelists account of the event. I like to think of it as
the Bolero eruption because it started of relatively quitely, got
louder and stronger as it progressed and had a spectacular finale.
Rob
Topic 2 of 99 [Geo]: Vulcanism
Response 555 of 997: Marcia (MarciaH) * Fri, Aug 17, 2001 (14:54) * 1 lines
Mmm... I know what you mean by a Bolero (by Ravel) eruption. Kilauea's are often that way when new episodes occur. First the merest little harmonic tremors begin. They slowly and unrelentingly build and build until enough magma has risen into the system that it must escape. A fissure appears and little molten blobs are hurled into the air - higher and higher.... till a full-fledged curtain of fire has established itself. As a grand climax, the curtain seals itself off except for the strongest vent, then the lava bursts in primal frenzies into the sky. *Sigh* I would like to see another such eruption, but I have already seen many of them - probably far more than my share!
Topic 2 of 99 [Geo]: Vulcanism
Response 556 of 997: Marcia (MarciaH) * Fri, Aug 17, 2001 (17:53) * 181 lines
Kilauea Volcano Watch - August 16, 2001
The opening of a new viewing area of the eruption
At 2:00 p.m. on Friday, August 17, the County of Hawai`i officially
opened to the public a new viewing area of the current eruptive activity.
The viewing area overlooks the spectacular seascape of the lava bench and
accompanying black sand beach at the ocean entry east of Kupapa`u.
This Kalapana Safe Viewing project evolved from a meeting of County,
State, and Federal agencies assembled by Mayor Harry Kim on July 23, 2001.
The meeting was convened to resolve a solution to the problem of a growing
number of people entering the Kalapana disaster zone to view the active
lava flows. The decision arrived at this meeting was that, given the
present location of the ocean entry, a safe viewing area with easy access
would be established.
With the establishment of this viewing area, the lament that we often
hear from both residents and visitors about not being able to see molten
lava should diminish. The activity at the ocean entry will satisfy most
lava buffs.
In addition to the multi-governmental agencies, subsequent meetings
included a member of the Kalapana community and representatives of the
travel industry. Responsibilities for various aspects of the project were
assigned and progress reported.
The task of the U.S. Geological Survey's Hawaiian Volcano Observatory
in this project was viewer safety. We were asked to outline the boundaries
of the public viewing area, to help route a trail from the end of the road
to the viewing area, and to advise on signage that would inform the public
of possible volcanic hazards. Informational posters were made from
illustrations in USGS Fact Sheet 152-00 (Viewing Hawai`i's Lava Safely --
Common Sense is Not Enough) prepared by HVO. HVO personnel will also
assist in training local interpreters stationed at the viewing site.
The remarkable feature of this project was the positive "can do"
attitude displayed by all the people involved. To feel the synergy of the
various governmental agencies and community groups was exhilarating. And
the overriding concern of the group was to protect and respect the property
and culture of the local Kalapana community while providing everyone an
opportunity to see and experience a rare natural phenomenon.
From inception to dedication, the Kalapana Safe Viewing project took
only 25 days to complete. The bulk of the work was the widening and
smoothening of 4.3 km (2.6 miles) of a four-wheel-drive bulldozed road.
The County Public Works Department and the State Highways Division worked
closely together to accomplish this task. Now vehicles up to a
15-passenger van can easily traverse from the end of the pavement of
Highway 130 to the 160 marked parking stalls of the viewing area.
A well-identified trail leads from the parking area to the viewing
area. HVO laid out the route of the trail, and the County Public Works,
with help from Hawai`i Volcanoes National Park, set out the reflective
posts and blinkers.
Our selection of the viewing area was based on safety issues. The
location is upwind of the highly acidic and glass-laced steam plume and is
far enough away from the bench to avoid any possible explosive debris.
Most vantage points within the viewing area provide a clear line of sight
to the ocean entry of lava. Boundaries of the viewing area are delineated
by barricades connected with rope.
Signs are placed throughout the area to help viewers have a safe and
memorable visit. People who ignore the signs may encounter problems,
especially if they go beyond the bounds of the viewing area and onto the
lava bench and beach. We wrote about the hazards posed by the lava bench
in last week's column. We again emphasize that the black sand beach is
also part of the bench and subject to collapse.
We encourage everyone to take advantage of this opportunity to see
the lava entering the ocean. The U.S. Geological Survey's Hawaiian Volcano
Observatory is proud to have participated and contributed to the Kalapana
Safe Viewing project.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week. Lava moves away from the vent toward the
ocean in a network of tubes and descends Pulama pali in two separate areas.
Scattered small surface flows, primarily ooze-outs from inflated areas in
the coastal flats, are occasionally observed. Lava continued to enter the
ocean in the area east of Kupapa`u throughout the week. The public is
reminded that the ocean entry areas are extremely hazardous, with possible
collapses of the new land. The steam cloud is extremely hot, highly
acidic, and laced with glass particles. Swimming at the black sand beach
of the bench can be a blistering or even deadly venture.
One earthquake was reported felt during the week ending on August 16,
2001. Residents island-wide felt an earthquake at 10:14 p.m. on Friday,
August 10. The magnitude-4.5 earthquake was located 9 km (5.4 mi) west of
Pahala at a depth of 10.9 km (6.5 mi).
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
U.S. Geological Survey
Hawaiian Volcano Observatory
PO Box 51, Hawaii National Park, HI 96718
Phone (808) 967-7328 FAX (808) 967-8890
ALASKA VOLCANO OBSERVATORY
Weekly Update
Friday, August 17, 2001 10:30 AM ADT (1830 UTC)
ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior but are not considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
in color code GREEN. All are at or near normal levels of background
seismicity. AVO did not detect ash plumes or significant elevated surface
temperatures in the vicinity of any volcano.
Abbreviated color code key (contact AVO for complete description):
GREEN volcano is dormant; normal seismicity and fumarolic activity
occurring
YELLOW volcano is restless; eruption may occur
ORANGE volcano is in eruption or eruption may occur at any time
RED significant eruption is occurring or explosive eruption expected
at any time
Volcano information on the internet: http://www.avo.alaska.edu
Recording of the status of Alaska's volcanoes (907) 786-7478
Kamchatkan Volcanic Activity
INFORMATION RELEASE 52-01
Friday, August 17, 2001, 12:46 KDT (23:46 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity was above background this past week. Seventeen MI>=2 and
five MI>=1.7 earthquakes were registered. Continuous spasmodic volcanic
tremor amplitude was, on average, > 6.0x10-6 mps on August 9-14. Volcanic
tremor amplitude decreased gradually to background levels from 01:00 until
13:00 KDT on August 15 (12:00 to 24:00 UTC on August 14).
Observers in Klyuchi reported that gas and steam plumes rose 1200-1500 m
above the dome (3,650-3,950 m; 12,050-13,050 ft. ASL) at 09:00 KDT on
August 11 (20:00 UTC on August 10) and at 09:40 KDT on August 12 (20:40 UTC
on August 11). At 16:00 KDT (03:00 UTC) on August 15 a gas and steam plume
rose 100 m above the dome (2,550 m; 8,400 ft. ASL). At other times, clouds
obscured the volcano.
An AVHRR satellite image, at 07:23 KDT on August 12 (18:23 UTC on August
11), showed a 4-pixel thermal anomaly (two pixels of 49.5 degrees C within
a background near 3 degrees C) at the active dome area. A faint 2-pixel
thermal anomaly was seen in an image at 06:59 KDT on August 13 (17:59 UTC
on August 12). An image, at 17:42 KDT (04:42 UTC on August 15), showed a
1-pixel thermal anomaly (49 degrees C within a background near 19 degrees
C) at the volcano and a gas-steam plume extending for 75 km to the
southeast. A 2-3-pixel thermal anomaly was seen in an image at 07:06 KDT
on August 17 (18:06 UTC on August 16).
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was above background on August 15, but was at background
levels at all other times. Three MI>=1.7 and four MI>=2 earthquakes were
registered on August 15. On August 13, a gas and steam plume rose 100 m
above the crater (4,850 m, 16,000 ft. ASL). At other times, clouds obscured
the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity on August 13 was registered under the volcano. At other
times, seismic activity was at background levels. On August 10 the volcano
was quiet. Observers in Kozirevsk village reported that at 07:50 KDT on
August 13 (18:50 UTC on August 12) a gas and steam plume rose 500 m above
the dome (3,400 m, 11,200 ft. ASL) and extended west 15 km. At other times,
clouds obscured the volcano.
GMS satellite images showed a possible low-level gas-steam plume near the
summit of the volcano between 09:32-14:32 KDT on August 10 (20:32 - 01:32
UTC on August 09).
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky and Koryaksky volcanoes was at background levels.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m.
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
Seismic activity was at background levels. On August 09, 12, 14, both
volcanoes appeared quiet. At other times, clouds obscured the volcanoes.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS.
Topic 2 of 99 [Geo]: Vulcanism
Response 557 of 997: Marcia (MarciaH) * Fri, Aug 17, 2001 (18:09) * 23 lines
Near-Death on the Ocean Floor
When an oceanographic instrument was hit by a
scorching lava flow in 1998, it might well have been fried.
But the instrument serendipitously survived to tell its tale.
In this week’s issue of Nature, researchers report that it
captured the most complete picture of an underwater
eruption ever. Scientists say the data confirm existing
models of underwater volcanic eruptions.
Geophysicist Christopher Fox and his colleagues at the
University of Oregon have maintained instruments at the
Axial Volcano 500 kilometers off the Oregon coast for 15
years to study the dynamics of volcanic activity on the
seafloor. In October 1997, they deployed a
“rumbleometer,” an instrument that precisely measures
ocean depth, current, and temperature near the volcano.
They intended to use it to watch movements of the
seafloor prior to eruptions. But when Axial came to life in
what is known as a sheet flow on 25 January 1998, the
rumbleometer unexpectedly got caught in the lava's path.
more... http://www.academicpress.com/inscight/08152001/graphb.htm
Topic 2 of 99 [Geo]: Vulcanism
Response 558 of 997: Marcia (MarciaH) * Fri, Aug 17, 2001 (18:32) * 23 lines
Super Volcanoes: Satellites Eye Deadly Hot Spots
By Robert Roy Britt
Senior Science Writer
posted: 07:00 am ET
07 August 2001
The latest eruption of Mt. Etna in Sicily, which has destroyed a few buildings,
shut down the airport and crept into a ski area, produces dramatic nighttime
video of hot rolling lava and explosive fireworks. But compared to the known
history of volcanoes and even its own past, Etna's 2001 pyrotechnic show is
so far geologically pathetic.
Likewise, the eruption of Mt. St.
Helens in 1980 was a volcanic sneeze compared to what scientists
say America will experience one day. And a mysterious four-inch-high
bulge in the ground of central Oregon is, so far, little more than a
conversation piece.
Sooner or later, geologists warn, a "super volcano" will strike.
more...
http://space.com/scienceastronomy/planetearth/volcano_monitor_010807-1.html
Topic 2 of 99 [Geo]: Vulcanism
Response 559 of 997: Marcia (MarciaH) * Mon, Aug 20, 2001 (17:13) * 234 lines
GVP/USGS Weekly Volcanic Activity Report 1-7 August 2001
http://www.volcano.si.edu/gvp/usgs/
New Activity/Unrest: | Bezymianny, Russia | Etna, Italy | Mayon,
Philippines | Shiveluch, Russia |
Ongoing Activity: | Kilauea, USA | Popocatépetl, México | Soufrière Hills,
Montserrat | Tungurahua, Ecuador |
New Activity
BEZYMIANNY Kamchatka Peninsula, Russia 55.98°N, 160.59°E; summit elev.
2,882 m; All times are local (= UTC + 12 hours)
The level of Concern Color Code
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm was raised from
Yellow to Red (the highest level) on 7 August after a relatively large
eruption occurred that day. Prior to the eruption, during 28 July-3 August,
seismic activity was at background levels; weak, long local seismic events
(possible collapses and/or avalanches) were recorded, and weak fumarolic
activity was observed. On 6 August AVHRR imagery showed a three-pixel
thermal anomaly on the volcano. On 7 August at 1128 an ash cloud was
observed from the town of Klyuchi rising 5 km above the volcano and
drifting to the ESE. By 1215 the ash cloud was at a maximum height of 10 km.
Background. Prior to its noted 1955-56 eruption, Bezymianny volcano had
been considered extinct. Three periods of intensified activity have
occurred during the past 3,000 years. The latest period, which was preceded
by a 1,000-year quiescence, began with the dramatic 1955-56 eruption. That
eruption, similar to the 1980 event at Mount St. Helens, produced a large
horseshoe-shaped crater that was formed by collapse of the summit and an
associated lateral blast. Subsequent episodic but ongoing lava-dome growth,
accompanied by intermittent explosive activity and pyroclastic flows, has
largely filled the 1956 crater.
Sources: KVERT via the Alaska Volcano Observatory
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm,
Tokyo VAAC http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
Bezymianny Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/bezymian/var.htm
from the monthly Bulletin of the Global Volcanism Network
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
News articles stated that around 1 August lava stopped advancing towards
the Rifugio Sapienza tourist area, although lava in other parts of the
volcano slowly continued to advance. According to the Toulouse VAAC, narrow
ash clouds that rose to below 5.5 km a.s.l. were occasionally visible in
satellite imagery and on Sistema Poseidon’s web cam. The international
Fontanarossa airport in Catania was closed, for the fourth time since the
eruptive period began, during 2-5 August due to ash clouds in the area. The
amount of ash emitted from the volcano decreased on 5 August and only steam
with small amounts of ash located close to the ground was visible on the
web cam.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Sources: Toulouse VAAC http://www.ssd.noaa.gov/VAAC/OTH/FR/messages.html,
Charles Rivière’s web site
http://perso.club-internet.fr/rivierec/aout_2001.htm,
Associated Press
http://dailynews.yahoo.com/h/ap/20010806/wl/italy_volcano_32.html
Etna Reports
http://www.volcano.si.edu/gvp/volcano/region01/italy/etna/var.htm from
the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
Volcanic activity during 1-4 August at Mayon consisted of high SO2
emission, high- and low-frequency harmonic tremor and low-frequency
volcanic earthquakes, slight inflation of the edifice, and the ejection of
lava fragments up to 100 m above the crater rim. PHIVOLCS stated that
activity had decreased since the 26 July eruptions and the volcano was in a
mild state of eruption. According to news reports, approximately 26,500
people were still evacuated from their homes near the volcano. Mayon
remained at Alert level 5, the highest level.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Sources: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm,
Manila Bulletin http://www.mb.com.ph/main/2001%2D08/mn080508.asp,
Associated Press
http://dailynews.yahoo.com/h/ap/20010806/wl/philippines_volcano_1.html
Mayon Reports
http://www.volcano.si.edu/gvp/volcano/region07/luzon/mayon/var.htm from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
During the week seismic activity remained above background levels, with
many small earthquakes occurring within the volcano’s edifice and several
different seismic signals (explosion, avalanche, collapse) recorded
locally. The level of continuous spasmodic volcanic tremor increased on 28
July and again on 30 July. Gas-and-steam plumes were observed rising to a
maximum height of 1 km above the dome and on the night of 1 August ash fell
in the town of Klyuchi, 46 km from the volcano. One- to three-pixel thermal
anomalies were occasionally visible in satellite imagery. The volcano
remained at Concern Color Code Orange
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
http://www.volcano.si.edu/gvp/volcano/region10/kamchat/shiveluc/var.htm
from the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Moderate amounts of lava continued to flow into the sea at the E Kupapa`u
entry. Surface lava flows were occasionally visible to the E and W of the
current lava flow field. Pahoehoe lava was visible slowly spreading on the
coastal flat seaward of the base of the Pulama pali scarp. Generally, weak,
rather steady tremor and a few small earthquakes continued beneath
Kilauea’s caldera. Near Pu`u `O`o, continuous tremor occurred at
weak-to-moderate levels. Elsewhere, seismicity was at normal levels.
Tiltmeters across the volcano showed no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
http://www.volcano.si.edu/gvp/volcano/region13/hawaii/kilauea/var.htm
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m
Low-level volcanic activity occurred at Popocatépetl during the week.
Several small emissions occurred at the volcano that were mainly composed
of steam, gas, and small amounts of ash.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html
Popocatépetl Reports
http://www.volcano.si.edu/gvp/volcano/region14/mexico/popo/var.html from
the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev.
1,030 m; All times are local (= UTC 4 hours)
Volcanic activity rapidly declined after the lava dome at Soufrière Hills
partially collapsed on 29 July. Observation flights after the collapse
revealed that the general summit region had been lowered by about 150 m.
There was also a complex amphitheater-shaped scar several hundred meters
deep incised into the core of the dome at the head of the Tar River Valley.
A new dome was growing within the scar. The Washington VAAC reported that a
minor eruption occurred on 4 August at 0300. The eruption produced ash that
traveled in two different directions; the first ash cloud rose to ~4.6 km
a.s.l. and drifted NW; the second cloud rose to ~9.7 km a.s.l. and drifted NE.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Sources: Montserrat Volcano Observatory http://www.mvo.ms/,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
http://www.volcano.si.edu/gvp/volcano/region16/w_indies/soufhill/var.htm
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
IG reported that during 2 August until at least 3 August there was an
increase in volcanic activity at Tungurahua. Continuous tremor began on 3
August at 1400 that may have been associated with continuous ash emission.
In addition, the Washington VAAC reported that several eruptions occurred
during the week, with the largest eruption on 5 August at 1700 producing an
ash cloud that rose to ~12.5 km a.s.l.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
http://www.volcano.si.edu/gvp/volcano/region15/ecuador/tungurah/var.htm
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 560 of 997: Marcia (MarciaH) * Mon, Aug 20, 2001 (17:15) * 52 lines
*******************************************
CSAV/HVO Volcano Hazards Monitoring Course
*******************************************
From: Donald Thomas
Center for the Study of Active Volcanoes and Hawaiian Volcano Observatory
International Training Course in Volcano Hazards Monitoring
Hilo, Hawaii
The Center for the Study of Active Volcanoes announces its twelfth
annual International Training Course in Volcano Hazards Monitoring to be
held on the Island of Hawaii from May 20 through June 28, 2002. The
course is offered in cooperation with the US Geological Survey Hawaiian
Volcano Observatory and is intended for technicians and professionals
who are currently working, or who will work, in the field of volcano
hazards assessment, monitoring, and management/response. Both
classroom instruction and field training will be provided in five
modules: Physical Volcanology; Volcano Seismology; Ground Deformation
Monitoring; Geochemistry of Thermal Discharges; and Civil Defense and
Hazard Management.
The Physical Volcanology module provides training in the techniques of
identifying and mapping different types of volcanic deposits and the
application of this information to the assessment of the types and
frequencies of volcanic hazards occurring in a particular volcanic region.
Volcano Seismology training includes instruction in theoretical aspects
of seismology, the application of both digital and analog equipment to
volcano monitoring, training in the deployment and maintenance of a
seismic network in the field, and interpretation and analysis of the
seismic signals recorded.
Ground Deformation studies includes the techniques of precise leveling,
electronic distance measurements (laser geodemeter), satellite (global
positioning system), total field station, and dry tilt monitoring of
active volcanic systems.
The Geochemistry program includes field sampling and analysis of
volcanic gases, remote methods (COSPEC) of monitoring volcanic gases,
acute health hazards from volcanic gases and safety procedures and
equipment used by field crews in hazardous locations.
Civil Defense aspects of the course cover a brief overview of the
requirements for public notification of impending hazards and the design
and establishment of an emergency response center for volcanic and other
natural hazard events.
Course applications are now being accepted for the Summer 2002 program.
Limited tuition waivers and partial scholarships are available for
participants from lesser-developed countries. For more information
visit our web site at: www.uhh.hawaii.edu/~csav. To apply, please contact:
Darcy Bevens
CSAV
UH-Hilo
200 W. Kawili St.
Hilo, HI 96720-4091
Topic 2 of 99 [Geo]: Vulcanism
Response 561 of 997: Marcia (MarciaH) * Mon, Aug 20, 2001 (17:18) * 97 lines
*********************************************
International Central Andes Volcanological
Field Course - VIII Edition
*********************************************
From: jose viramonte viramont@unsa.edu.ar
DEAR COLLEAGUES:
We are glad to announce the 8th of CENTRAL ANDES VOLCANOLOGICAL FIELD
COURSE, which will take place in the Central Andes of Northwestern
Argentina ( Salta and Catamarca Provinces) from 2nd to 10th October 2001.
It include 1 day of theoretical lectures and 7 days of field practices on
ignimbrites, surges, air fall, lavas, etc in a spectacular volcanic scenery.
For further information please visit our website at:
http://www.unsa.edu.ar/~geonorte/cursos/curvol.html
or mail to: curvol@unsa.edu.ar
Prof. Dr. Jose Viramonte
Director
*********************************
GPS job opportunity
*********************************
From: John Beavan J.Beavan@gns.cri.nz
This advertisement has been previously posted to a number of
other e-mail lists. In case we have missed anyone in the
volcano geodesy community, we are also posting it here.
GEODESIST/GEOPHYSICIST
----------------------
The Institute of Geological and Nuclear Sciences (GNS) and
the Earthquake Commission (EQC) are embarking on a ten-year
collaborative project called GEONET to upgrade the
geological hazards monitoring network in New Zealand.
GEONET will provide real-time monitoring and data
collection for rapid response and research into earthquake,
volcano, and landslide hazards associated with the Pacific-
Australian tectonic plate boundary. As part of this
upgrade, at least 100 continuous GPS stations will be
deployed over the next 5-6 years, primarily in dense
arrays, to monitor and study subduction and volcanic
processes. Further information on the GEONET Project can be
found at http://www.gns.cri.nz/news/release/geonet.htm
GNS has a vacancy for a Geodesist or Geophysicist
specialising in the application of GPS to crustal
deformation. The appointee will join the multidisciplinary
team which has specific responsibilities to the GEONET
project as well as contributing to complementary research
projects and commercial jobs. Duties will include:
1. Contributing to the scientific design of the GEONET GPS
volcanic and tectonic network, and quality control of the
data;
2. Assisting in site selection and installation of precise
GPS instruments;
3. Contributing to the analysis, modelling, scientific
interpretation and reporting of data from the GEONET GPS
network, and other research projects complementary to
GEONET.
The ideal candidate will have:
1. A recognised advanced research qualification in a
relevant discipline;
2. Demonstrated excellence in the analysis, interpretation
and modelling of geodetic GPS data;
3. Specialist knowledge of ground deformation associated
with earthquake and/or volcanic systems;
4. Knowledge of precise GPS systems.
The position is based in Wellington, New Zealand and
provides a unique opportunity to join a world-class project
team engaged in research into plate tectonics in one of the
world's most exciting natural laboratories.
Further information on GNS and this position can be
obtained from Hugh Cowan, h.cowan@gns.cri.nz, or from
www.gns.cri.nz/careers. Applications including a covering
letter, CV and a completed application form should be
forwarded to:
Human Resource Consultant
Institute of Geological and Nuclear Sciences
PO Box 30 368
Lower Hutt, New Zealand
Topic 2 of 99 [Geo]: Vulcanism
Response 562 of 997: Marcia (MarciaH) * Mon, Aug 20, 2001 (20:31) * 47 lines
*********************
LASI field workshop
*********************
From: Christoph Breitkreuz
Colleagues,
Nick Petford and I would like to inform you about an international field
workshop titled:
Physical geology of subvolcanic systems: Laccoliths, sills and dykes (LASI)
which will take place at the TU Bergakademie Freiberg in Germany, octobre
5th - 7th, 2002.
Introduction and further informations:
http://www.geo.tu-freiberg.de/dynamo/LASI.htm
With kind regards,
Christoph Breitkreuz
*******************************
Hawaii bibliographic database
*******************************
From: "Thomas L. Wright"
Hawaii bibliographic database
A comprehensive bibliographic database covering all references pertinent to
Hawaiian volcanism (Wright and Takahashi, 1998) is available via anonymous
ftp (not InterNet) at onyx.wr.usgs.gov/pub/twright. Subdirectories for
Macintosh and Windows users each contain a readmefirst file. Upload this
text file first for instructions regarding the rest of the upload
procedure. Other files include information on searching, keyword structure,
and the three-part database. Part I covers literature from 1790 through
1989. Part II covers literature from 1990 to the present. Part III
comprises popular speleological literature, particularly emphasizing
references that contain maps and/or cross-sections of lava tubes.
Speleological papers that address the mechanics of lava tube formation are
included in parts I and II. The database is readable using the EndNote
bibliographic database program, available via free download from
"http://www.endnote.com".
The database is updated three times a year. The date of latest update is on
the file name in the ftp subdirectory, and in the readmefirst files.
Questions and comments regarding the database should be directed to Tom
Wright (twright@usgs.gov) or Jane Takahashi (jtakahashi@usgs.gov).
Wright, T.L., and Takahashi, T.J., 1998, Hawaii bibliographic database:
Bulletin of Volcanology, v. 59, no. 4, p. 276-280.
Thomas L. Wright
Volcano Research Center
Earthquake Research Institute, University of Tokyo
1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032 JAPAN
Topic 2 of 99 [Geo]: Vulcanism
Response 563 of 997: Marcia (MarciaH) * Mon, Aug 20, 2001 (20:43) * 71 lines
***********************
Tungurahua, Ecuador
***********************
Since 6 August, Ecuador's Tungurahua has been in constant eruption
[reportedly with crop damage to the W from its ash falls]. The 20 August
report shows high seismic activity continuing on the 19th, constant ash
emissions to 3 km above the summit, glowing blocks cascading down the
flanks and roarings or cannon-like sounds.
Poorly translated from:
http://www.epn.edu.ec/~igeo/Vulcanologia/Volcanes/Tungurahua/Informet/inform
et.html
SEISMICITY
197 earthquakes of long period have been registered. The volcanic
tremor has increased slightly during last the 24 hours.
EXPLOSIONS AND EMISSIONS
10 emissions have been registered.
OBSERVATIONS
During afternoon of yesterday it was possible to observe the constant
exit of ash. It was observed that the ash pen reached a height of 3
km on the summit of the volcano and divided in two parts one towards
the SW and another one towards the SE. Additionally during the night it was
possible to be observed incandescent blocks rolling by flanks, in
addition sounds similar to roars were listened to. On the other hand,
the explosion happened at dawn of today generated an ash column that
reached 1 km of height and a strong sound similar to cannon shot that
could be listened to from the cities of Baths, Juive and Pillate.
According to reports of WASHINTONG VAAC the ash emitted by the volcano
went to the W-SW and THAT of the same one reaching a height of
approximately 1 km on the summit.
STATE Of the VOLCANO From Friday of the last week the activity of the
volcano increased slightly and until the moment it stays in levels
characterized by a high number of events of long period
***************************
San Cristobal, Nicaragua
***************************
Lava lake at San Cristobal?
San Cristobal volcano (Nicaragua) began to show increased tremor on 11
August, with rumblings noted on 12 August. Glow over the crater on the 14th
is believed to be the reflection of a lava lake deep within the crater. San
Cristobal has been in a state of mild eruptiveness since May.
Loose translation of:
http://www.ineter.gob.ni/geofisica/vol/cristobal/com/20010815/com20010815.htm
***************************
Mt.Rainier "glacier burst"
***************************
Further tweaking of the Rainier "glacier burst"
It appears that the laharic event of the 14th took place at 9 pm instead of
10 pm and that it came not from the Van Trump Glacier but the Kautz
Glacier. Further small laharic events are anticipated.
See:
http://vulcan.wr.usgs.gov/Volcanoes/Cascades/CurrentActivity/current_updates
.html
Topic 2 of 99 [Geo]: Vulcanism
Response 564 of 997: John Tsatsaragos (tsatsvol) * Tue, Aug 21, 2001 (03:44) * 4 lines
Hi Marcia,
I have not said to you it, but near to Volos and more near the village Makrinitsa, it exists a very old inactive volcano. Crater is found in a place of mountain Pilion that is named Sarakinos, NNW of Volos. I have seen the crater but could not I learn more.
John
Topic 2 of 99 [Geo]: Vulcanism
Response 565 of 997: Marcia (MarciaH) * Tue, Aug 21, 2001 (14:04) * 1 lines
I shall investigate it for both of us, in that case. If I can find references to cryptovolcanoes under the Appalachian mountain range in the eastern United States, perhaps I will be able to find yours. Fascinating, John! Many thanks for telling me about it. I had no idea...*Hugs* (I love a good research project!)
Topic 2 of 99 [Geo]: Vulcanism
Response 566 of 997: Marcia (MarciaH) * Wed, Aug 22, 2001 (18:01) * 15 lines
It's Party Time and it is raining outside so no one can see anything Mme Pele is doing at the moment:
VULCANALIA
VULCANALIA, a festival celebrated at Rome in honour of Vulcan, on the
23d of August (X Calend. Sept.) with games in the circus Flaminius, where
the god had a temple (Inscript. ap. Gruter. lxi.3, cxxxiv; Publ. Vict. de
regionib. urb. Romae, 9). The sacrifice on this occasion consisted of fishes
which the people threw into the fire (Varro, de Ling. Lat. vi.20). It was also
customary on this day to commence working by candlelight, which was
probably considered as an auspicious beginning of the use of fire, as the
day was sacred to the god of this element (Plin. Epist. iii.5). It was on the
day of this festival that the consul Q. Fulvius Nobilior received a severe
defeat from the Celtiberians, B.C. 153. It became an ater dies in
consequence (Appian, Hisp. 45).
Topic 2 of 99 [Geo]: Vulcanism
Response 567 of 997: Marcia (MarciaH) * Thu, Aug 23, 2001 (18:44) * 23 lines
*****************************
Ol Doinyo Lengai, Tanzania
*****************************
From: Roberto Carniel
Ol Doinyo Lengai: paroxysmal phase on 27 July 2001
On 27 July 2001 the natrocarbonatitic volcano Ol Doinyo Lengai, usually
characterized by small-scale eruptions, produced spectacular eruptive
activity during a visit by a team of scientists and volcanophiles led by
Fred Belton. We can well define this phase as "paroxysmal" as it was never
observed before (or at least documented). However, as we have seen other
deposits in the crater that may have been emplaced by similar processes, we
do not exclude that such paroxysmal phases can happen every few months.
A first set of pages documenting this eruption with photographs by Marco
Fulle and videos by Roberto Carniel is available on the website
STROMBOLI ON-LINE - http://stromboli.net.
From the homepage, follow the link "Ol Doinyo Lengai" under the section
"Big wide world". We plan to add more material, also documenting the
previous phases of the eruption, in the next weeks.
Roberto Carniel, University of Udine
Topic 2 of 99 [Geo]: Vulcanism
Response 568 of 997: Marcia (MarciaH) * Thu, Aug 23, 2001 (18:47) * 262 lines
GVP/USGS Weekly Volcanic Activity Report
15-21 August 2001
New Activity/Unrest: | Makian, Indonesia | San Cristóbal, Nicaragua |
Tungurahua, Ecuador |
Ongoing Activity: | Etna, Italy | Kilauea, USA | Philippines, Philippines
| Popocatépetl, México | Shiveluch, Russia | Soufrière Hills, Montserrat |
New Activity
MAKIAN Halmahera, Indonesia 0.32°N, 127.40°E; summit elev. 1,357 m; All
times are local (= UTC + 9 hours)
An eruption began at Makian on 16 August at 1930. During the eruption,
chunks of incandescent lava were ejected 75 m through the air. Residents
were evacuated to the S side of the island. The volcano is at Alert Level
Red.
Background. Makian volcano forms a 10-km-wide island near the southern end
of a chain of volcanic islands off the W coast of Halmahera and has been
the source of infrequent, but violent eruptions that have devastated
villages on the island. The large 1.5-km-wide summit crater, containing a
small lake on the NE side, gives the peak a flat-topped profile. Two
prominent valleys extend to the coast from the summit crater on the N and E
sides. Four parasitic cones are found on the western flanks. Eruption have
been recorded since about 1550; major eruptions in 1646, 1760-61, 1861-62,
1890, and 1988 caused extensive damage and many fatalities.
Source: Société Volcanologique Européenne
http://www.sveurop.org/gb/menu/fr_menu.htm
Makain Reports
from
the Bulletin of the Global Volcanism Network
SAN CRISTÓBAL Nicaragua 12.702°N, 87.004°W; summit elev. 1,745 m; All
times are local (=UTC - 6 hours)
There was renewed volcanic and seismic activity at San Cristóbal during the
week. During mid-August a gradual increase in seismic tremor and
long-period earthquakes began and the amount of tremor peaked during the
night of 11 August. The same night INETER personnel heard rumbling emanate
from the volcano. Seismicity began to decrease on 12 August and increased
again the night of 14 August, reaching the same level detected on 11
August. On 14 August incandescence was visible in the crater for the first
time during the current episode. INETER stated that the lava lake in the
crater illuminated gas and clouds above the summit crater. Seismic tremor
gradually decreased until approximately 1400 on 17 August when strong
seismic activity began again. Fumarolic activity increased during the
current episode and small lagoons within the crater had dried.
Background. The San Cristóbal volcanic complex, consisting of five
principal volcanic edifices, forms the NW end of the Marrabios Range. The
symmetrical 1,745-m-high youngest cone, San Cristóbal itself (also known as
El Viejo), is Nicaragua's highest volcano and is capped by a 500 x 600 m
wide crater. El Chonco, with several flank lava domes, is located 4 km to
the W of San Cristóbal; it and the eroded Moyotepe volcano, 4 km to the NE
of San Cristóbal, are of Pleistocene age. Volcan Casita contains an
elongated summit crater and lies immediately E of San Cristóbal; Casita was
the site of a catastrophic landslide and lahar in 1998. The
Plio-Pleistocene La Pelona caldera is located at the eastern end of the San
Cristóbal complex. Historical eruptions from San Cristóbal, consisting of
small-to-moderate explosive activity, have been reported since the 16th
century. Some other 16th-century eruptions attributed to Casita volcano are
uncertain and may pertain to other Marrabios Range volcanoes.
Source: Instituto Nicaragüense de Estudios Territoriales
http://www.ineter.gob.ni/geofisica/vol/cristobal/cristobal.html
San Cristóbal Reports
from the Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC -5 hours)
The series of eruptions that began at Tungurahua on 6 August continued
during the week. Seismic activity was characterized by many long-period
earthquakes and seismic signals that represented ash emissions. Several
sporadic explosions occurred, with the largest explosion beginning on 15
August at 2231. The eruption produced an ash cloud that rose to 12.2 km
a.s.l. IG reported that on 17 August volcanic activity increased slightly
and incandescent material was ejected up to 1 km W of the crater. According
to news reports, as of 15 August ash affected more than 23,000 people,
blanketed approximately 89,000 acres of crops, and killed an undetermined
number of livestock. The Alert Level remained at Yellow in the town of
Baños and at Orange for the rest of the population in the high-risk zone,
as it has since 5 September 2000.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador's capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html, Associated
Press http://dailynews.yahoo.com/h/ap/20010815/wl/ecuador_volcano_2.html,
Reuters http://dailynews.yahoo.com/h/nm/20010817/wl/ecuador_volcano_dc_1.html
Tungurahua Reports
from the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
During the week volcanic activity was relatively low at Etna, with no
explosions or lava flows. There were several small earthquakes, and slight
degassing at fissures on the volcano's flanks. Vapor was emitted from the
summit craters, and was accompanied by occasional plumes of brown ash at
Bocca Nuova crater.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna's summit craters
began in 1995.
Sources: Charles Rivière's web site
http://perso.club-internet.fr/rivierec/aout_2001.htm
Etna Reports
from
the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava continued to enter the sea at the E Kupapa`u entry. Surface lava flows
were visible on the coastal plain in both the E and W branches of the
current flow field. A short, stubby surface flow was visible halfway down
the Pulama pali scarp. On 15 August volcanic tremor abruptly increased at
Kilauea's summit and at Pu`u `O`o, but it reached only moderate-to-low
levels. Generally, weak, rather steady tremor and a few small earthquakes
continued beneath Kilauea's caldera. Tiltmeters across the volcano showed
no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world's most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey's Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
Volcanic activity remained relatively low at Mayon during the week. Few
rockfalls were observed, seismicity was relatively low, incandescence was
not visible in the crater, and no inflation was detected at the volcano's
summit. SO2 emission rates reflected continuous degassing of residual
magma. Because volcanic and seismic activity had been declining for the
previous 2 weeks, on 21 August PHIVOLCS decreased the Alert Level at the
volcano from 4 (hazardous eruption imminent) to 3 (increased tendency
towards eruption). As a consequence, the Extended Danger Zone (EDZ) in the
SE returned to the original 6-kilometer radius Permanent Danger Zone (PDZ).
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon's most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Source: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
Mayon Reports
from
the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC - 5 hours)
Small emissions of steam, gas, and small amounts of ash continued at
Popocatépetl. The Mexico City MWO reported that on 17 August at 1514 an ash
emission produced a cloud that rose to 7.3 km a.s.l. The Washington VAAC
reported that GOES-8 satellite imagery did not show an ash plume, but did
show an occasional hotspot. CENAPRED reported that recent activity was
related to the growth of a new lava dome inside the crater. The volcano
remained at Alert Level Yellow Phase II.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
Seismic activity remained above background levels during the week and
included several small earthquakes. On 15 August volcanic tremor decreased
gradually to background levels. Observers in Klyuchi reported that on 11
August gas-and-steam plumes rose 1.2-1.5 km above the dome. Several thermal
anomalies were recorded on satellite imagery, as well as a gas-and-steam
plume extending 75 km SE. Shiveluch remained at Concern Color Code Orange
.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
Volcanic activity remained low during 10-17 August. Weak banded tremor
began on 14 August and continued throughout the week. The new lava dome
continued to grow within the scar produced from the 29 July partial dome
collapse. Deposits in the upper reaches of the Tar River Valley indicated
that the new dome had produced several small pyroclastic flows.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvo.ms/
Soufrière Hills Reports
from the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Topic 2 of 99 [Geo]: Vulcanism
Response 569 of 997: Marcia (MarciaH) * Fri, Aug 24, 2001 (14:50) * 6 lines
Rob has reminded me of something I had forgotten about Volcano Ol Doinyo Lengai, Tanzania. It erupts carbonate lavas as black as soot.
Ol Doinyo Lengai is a stratovolcano, located in northern Tanzania, at 2.751°S / 35.902°E (summit elevation: 2890m; location map). It is a very special volcano, producing so-called «natro-carbonatitic» lava, very rich in sodium and carbonates. The lava has a very low viscosity (i.e. it is «very liquid») and emerges at temperatures of between 500 and 590°C only, so it does not
glow in the dark. This is the «coolest» lava of any known active volcano.
Great photos and more information:
http://educeth.ethz.ch/stromboli/perm/lengai/index-e.html
Topic 2 of 99 [Geo]: Vulcanism
Response 570 of 997: Marcia (MarciaH) * Mon, Aug 27, 2001 (17:10) * 27 lines
ALASKA VOLCANO OBSERVATORY Weekly Update
Friday, August 24, 2001 11:30 AM ADT (1930 UTC)
ALASKA VOLCANOES
Seismic activity is monitored in real time at 22 volcanoes in Alaska.
Satellite images of all Alaskan volcanoes are analyzed daily for evidence
of ash plumes and elevated surface temperatures. Some volcanoes may
currently display anomalous behavior but are not considered to be at a
dangerous level of unrest.
Spurr, Redoubt, Iliamna, Augustine, Snowy, Griggs, Katmai, Novarupta,
Trident, Mageik, Martin, Aniakchak, Pavlof, Dutton, Isanotski, Shishaldin,
Fisher, Westdahl, Akutan, Makushin, Great Sitkin, and Kanaga volcanoes are
in color code GREEN. All are at or near normal levels of background
seismicity. AVO did not detect ash plumes or significant elevated surface
temperatures in the vicinity of any volcano.
Abbreviated Color Code Key (contact AVO for complete description):
GREENvolcano is dormant; normal seismicity and fumarolic activity occurring
YELLOWvolcano is restless; eruption may occur
ORANGEvolcano is in eruption or eruption may occur at any time
REDsignificant eruption is occurring or explosive eruption expected at any
time
Topic 2 of 99 [Geo]: Vulcanism
Response 571 of 997: Marcia (MarciaH) * Mon, Aug 27, 2001 (17:55) * 32 lines
Deadly Atlantic Waves Studied
By RANDOLPH E. SCHMID, Associated Press Writer
WASHINGTON (AP) - Giant ocean waves could slam into the East Coast if a volcano across the Atlantic in the Canary Islands splits open, two scientists warn.
The Cumbre Vieja volcano last erupted in 1949. It has not shown any recent indications of activity, but the threat could become real someday.
If a new eruption caused an existing rift across the volcano to split open, a massive landslide could crash into the ocean. That could send waves rushing across the Atlantic - striking Cape Canaveral, Fla., for example, just nine hours later, according to geophysicists Steven N. Ward of the University of California at Santa Cruz and Simon Day of University College, London.
In what they said was a worst-case scenario, a wave nearly 70-feet high could strike parts of the East Coast. Giant waves also could crash into Africa and northeast South America.
Ward stressed that is unlikely and that smaller landslides would produce waves one-fourth to half that height.
``Let's not scare people,'' Ward said. ``Certainly there is no indication that this will happen anytime soon.''
``Even when there is an eruption, the probability of collapse is low,'' Day said. ``There may be many eruptions before the volcano is finally weak enough to collapse.''
Peter Lipman, a volcanologist with the U.S. Geological Survey (news - web sites) in Menlo Park, Calif., agreed that the threat exists from the volcano on the island of La Palma, off Africa's northwest coast. He, too, was cautious about when such a disaster might occur.
``These oceanic island volcanoes are, in geologic time, very subject to exactly the kind of process they describe,'' he said. ``Volcanoes try to keep on adding lava to a steep slope and eventually they get the slope so loaded that it fails.''
``I don't see this as something that is likely to happen very often at La Palma,'' he said. ``But it had a failure like this half a million years ago and will again in the future.''
Volcanologist Tom Simkin of the Smithsonian's National Museum of Natural History agreed that the threat, though small, does exist.
``We all know that big landslides do happen. It doesn't happen very often, but often enough that we ought to be paying attention to it,'' he said.
Ward and Day's findings are reported in the Sept. 1 issue of Geophysical Research Letters.
The massive wave, known as tsunami (soo-NAHM-ee), long have been known as a danger around the Pacific Ocean, where warning centers monitor the sea and alert coastal residents.
more... http://dailynews.yahoo.com/h/ap/20010827/sc/deadly_waves_1.html
Topic 2 of 99 [Geo]: Vulcanism
Response 572 of 997: Marcia (MarciaH) * Tue, Aug 28, 2001 (20:46) * 174 lines
***********************************
Indonesian Updates for July-August
************************************
From: http://www.vsi.dpe.go.id/news/624a.html
VOLCANIC ACTIVITY REPORTS
Information contacts: Dali Ahmad (dali@VSI.dpe.go.id)
Hetty Triastuty (hetty@VSI.dpe.go.id)
Nia Haerani (haerani@VSI.dpe.go.id)
Suswati (suswati@VSI.dpe.go.id)
VSI
Jalan Diponegoro 57 Bandung 40122
Fax : + 62 22 72 02 761
Tel: + 62 22 721 46 12
Weekly Report No. 624a
16-29 July, 2001
Karangetang
Siau island; 2°47' N, 125°29' E
Karangetang activity is continuing and dominated with small explosion,
avalanche and multi phase. Visual observations to the volcano reported that
main crater continued to eject white medium - grey of plume and hit 500 m
height. The other hand, lava flow is still lasting and flew down 1000 m to
Kahetang river, 1500 m to Batu Awang river and 1500 m to Keting river. At
the end flow often occurred material avalanche as far as 2500 m. Thundering
sound of avalanche was heard from Karangetang post observatory.
Uncontinuous volcanoc tremo is ongoing and the amplitude was about 1-12 mm,
but avalanche earthquake has 0.5-25 mm of amplitude. During the period
seismograph showed: 6 events of deep volcanic (VA), 2 events of tectonic,
479 events multiphase, 711 events small explosion, continues of avalanche
and uncontinuous of volcanic tremor earthquake. Based on that data
Karangetang seems increased compare to last data.
Karangetang volcano is in level 3.
Merapi
Central Java; 7°32.5' S, 110°26.5' E
Based on both of visual and seismic data Merapi showed stable in its
activity. Observer reported that solfatara is continuing, has white thin
color, low in pressure and rose 900 m above the summit. Meanwhile, lava
avalanche which occurred in 2.5 km in maximum distance traveled down to
Sat, Senowo and Lamat river.
Merapi volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
There was a major increasing at Lokon volcano, especially at seismicity
data. During the reporting time seismograph recorded volcanic tremor which
has a quite high of amplitude, was about 0.5-8 mm. But based on visual,
observer reported plume is still ejecting from Tompaluan crater, towered
25-150 m. Complete seismicity were: 146 events of deep volcanic (VA), 238
events of shallow volcanic, 59 events of tectonic and uncontinuous volcanic
tremor earthquake.
Lokon volcano is in level 2.
Ijen
East Java;8°3.5' S, 114°14.5' E
During two weeks, Ijen continued to produce white-grey of plume which rose
about 100 m height. Volcanic tremor was recorded on seismograph with
amplitude of about 0.5-2 mm. Others seismicity within the reporting time
listed below: shallow volcanic (VB) 51 events, 1 event of small explosion,
7 events of tectonic and uncontinuous volcanic tremor.
Ijen volcano is in level 2.
Anak Krakatau
Sunda Straits, 6°6'5.8" S, 105°25'22.3" E
On 21 July, 2001, Krakatau again showed its explosion activity which
accompanied with booming sound. That activity was recorded at infrasonic
microphone sensor which is installed at Pasauran post observatory. The
explosion was marked with accumulation of deep and shallow volcanic
earthquakes since beginning of July 2001. Seismicity during two weeks
dominated with explosion, deep and shallow volcanic earthquakes. Detail
data listed as follow: 52 events of deep volcanic (VA), 293 events of
shallow volcanic (VB), 21 events of explosion and 698 events of small
explosion earthquake.
Anak Krakatau is stated in level 2.
***********************************************
From: http://www.vsi.dpe.go.id/news/index.html
VOLCANIC ACTIVITY REPORTS
Information contacts: Dali Ahmad (dali@VSI.dpe.go.id)
Hetty Triastuty (hetty@VSI.dpe.go.id)
Nia Haerani (haerani@VSI.dpe.go.id)
Suswati (suswati@VSI.dpe.go.id)
VSI
Jalan Diponegoro 57 Bandung 40122
Fax : + 62 22 72 02 761
Tel: + 62 22 72 14 612
Weekly Report No. 625
30 July-12 August, 2001
Karangetang
Siau island; 2°47' N, 125°29' E
Based on seismicity, Karangetang seismicity within two weeks was dominated
with small explosion earthquake, avalanche and multiphase earthquakes.
Visual observations during the period reported that volcano edifice usually
covered by clouds, but when the weather clearly observer could notice plume
which appear from main crater. Plume was commonly in white medium - grey
color rose 600 m height. Lava flow and lava avalanche since first of August
was rarely.
Because of rain intensity was high during two weeks, cold lahar was occured
on 10 August, 2001 at Batu Awang river, resulting the road from Ulu Siau to
Ondong covered with sand as long as 60 m and the thickness of 5-40 cm. Also
lahar at Kahetang river covering road from Bus Station to Ulu Siau Pearl as
long as 50 m with the thickness was about 10-40 cm. Further more, no
victims has reported caused by the evidence.
Uncontinuous volcanic tremor has recorded with amplitude of 1-12 mm. Others
seismicity during two weeks were: 1 event of deep volcanic (VA), 7 events
of tectonic, 138 events of multiphase, 342 events of avalanche and 382
events of small explosion earthquake.
Karangetang volcano is in level 3.
G. Kerinci
West Sumatera
Kerinci showed again its power with an explosion which occurred on 9
August, 2001. Explosion which accompanied with booming sound was heard by
people whom worked in the rice field around the volcano. By visual
observation on 9 August at 09.25 from post observatory, observers noticed
that smog explosion was in dark to brownish color with high gas pressure,
towered about 700 m height above the summit. Explosion column trending to
north - north east as long as 5 minutes. Seismic data during the report
were: 6 events of deep volcanic (VA), 6 events of shallow volcanic (VB),
990 events of small explosion and 16 events of tectonic.
Kerinci volcano is in level 2.
Merapi
Central Java; 7°32.5' S, 110°26.5' E
During the time of report, observer reported that solfatara was commonly in
white thin color, low in pressure, and the maximum height was 425 m above
the summit. Lava avalanche was ongoing, trending to upstream of Sat,
Senowo, Lamat and Bebeng river, and the maximum distance was 2.8 km.
Seismic activity dominated with avalanche earthquakes. No lahar has
reported which occurred during the time.
Merapi volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E
Small explosion activity from Tompaluan crater is continuing towered about
25-250 m height. The color of plume was white thin. Base to the sesimicity
data, there was a significant decreasing at Lokon activity compare to the
report before. Seismograph continued to record uncontinuous volcanic tremor
with amplitude of 0.5-1 mm. Complete data listed as follow: 12 events of
deep volcanic (VA), 13 events of shallow volcanic (VB) and tectonic
earthquake was 59 events.
Lokon volcano is in level 2.
Ijen
East Java;8°3.5' S, 114°14.5' E
Ijen activity is continuing and still high. The crater continued to produce
white-grey of plume which reached 100 m height. Seismicity records showed
0.5-2 mm amplitude of volcanic tremor earthquakes. The other hand,
seismograph also noticed others sismicity such as shallow volcanic (VB) 17
events, small explosion 6 events and tectonic 6 events.
Ijen volcano is in level 2.
Anak Krakatau
Sunda Straits, 6°6'5.8" S, 105°25'22.3" E
Seismic activity on Krakatau volcano within two weeks dominated with small
explosion and explosion earthquakes. Infra sonic instruments which is
install at Pasauran post observatory recorded 14 events of explosion
earthquake. Meanwhile, the observers reported that plume emission was is
white-grey color and hit 500 m height. Detail seismic records listed as
follow: 40 events of shallow volcanic (VB), 123 events of explosion, 597
events of small explosion earthquake.
Anak Krakatau is stated in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 573 of 997: Marcia (MarciaH) * Tue, Aug 28, 2001 (20:52) * 78 lines
*******************************************************
AGU Volcanology, Geochemistry, and Petrology sessions
*******************************************************
The AGU 2001 Fall Meeting will be held in San Francisco from Dec. 10-14.
General meeting information is available at
http://www.agu.org/meetings/fm01top.html
Abstract deadlines are August 30 for mail submissions, and September 6 (UTC
1400) for web submissions. The AGU web site for submitting abstracts is
http://submissions3.agu.org/submission/entrance.asp
Below is a list of special sessions sponsored by or of interest to the
Volcanology, Geochemistry, and Petrology section. Full descriptions and
convenor information can be found through the Fall Meeting Special Sessions
search page at:
http://submissions6.agu.org/meetings_database/fm01sessions_search.asp
-----------
V01 General Volcanology, Geochemistry, and Petrology Contributions
V02 Geochemical and Isotopic Tracers of Earth Processes
V03 Conduit Processes During Explosive Basaltic Eruptions
V04 New Directions in Experimental Mineralogy and Petrology
V05 Understanding Volcanoes Through Multiparameter Measurements and Their
interpretation: A Session in Memory of Bruno Martinelli
V06 Nanoparticles in the Environment
V07 Volcanic Observations From Space: New Results From the EOS Satellite
Instruments
V08 Highly Siderophile Element Chemistry of the Earth, Moon, and Planets (A
Special Session in Honor of Dr. John Morgan)
V09 Experimental Volcanology: Sturtevant Memorial Session
V10 Heavy Element Stable Isotope Fractionations
V11 Trench to Subarc: Diagenetic and Metamorphic Mass Flux in Subduction
Zones (GERM/MARGINS Subduction Factory Session)
-----------
U04 Ten Years of Science From the 1991 Mount Pinatubo Volcano Eruption
G06 Explaining Geodetic Observations of Nonlinearly Time-Varying Surface
Deformation
G09 Temporal Gravity Observations and Crustal Deformation
G10 SRTM: Mission Status and Early Applications
GC02 Reconstructions of Nineteenth Century Climate
GP04 Full Vector Analyses of the Paleofield
GP05 Paleomagnetic Field Behavior on Historical to Million Year Timescales
GP06 Electrical Properties Across Margins: Active, Passive, and Fossil
NG02 Scaling and Fractals in Geophysics: In Honor of Mandelbrot's Fiftieth
Jubilee
NG03 Scaling Geophysics: Where We've Been, Where We're Going
NG04 Self-Organizing Complex Earth Systems
NG10 Nonlinear Structure of Geophysical Processes Before and After
Catastrophic Events
OS04 Source to Sink: Production, Transport, and Accumulation of Sediment
(With a Special Focus on Climate Signals and Impacts)
OS06 Database Efforts Within Marine Geology and Geophysics: New Tools for
Enhanced Data Access
OS11 Trace Elements and Isotopes in Oceanography
OS12 Oceanography of the Eastern Boundary Region of the Subtropical North
Atlantic Gyre
OS14 Hydrothermal Activity in Back-Arc Basins
P03 Mars Global Surveyor: Guiding the Future of Mars Exploration
P06 The Evolution of Volcanism on Mars
P07 Surface Mineralogy of Earth and Mars
P11 Advances in Modeling Flow Processes: Volcanoes, Floods, Impacts, and
Mass Movements
S07 Bumps, Lumps, and Clumps in the Mantle's Midsection
S11 Seismic and Hydro-Acoustic Constraints on Ocean Crustal Dynamics,
Volcanism, and Hydrothermal Fluid Circulation in the Northeastern Pacific
T02 Fortieth Anniversary of the Synthesis and Discovery of Stishovite
T04 Ophiolites and Continental Margins of the Pacific Rim and the Caribbean
Region
T05 Multidisciplinary Insights From Seismic Tomography, Mantle Dynamics,
Geological Origins, and Evolution
T06 The Impact of Rock Experimentation on Geodynamics: A Session in Honor
of Mervyn Paterson
T07 Processes Within the Subduction Factory
T09 Structure and Evolution of the Galapagos Volcanic Province
T12 Structure and Evolution of Earth's Deep Mantle
T13 Syn-Convergent Extension in the Apennines, Italy
T16 Quantitative Analysis of the Stratigraphic Record: New Approaches in
Cyclostratigraphy and the Dating of Sedimentary Sequence
T18 Hotspot-Ridge Interactions
T19 Role of Mass and Heat Transfer in Rock Fracturing
Topic 2 of 99 [Geo]: Vulcanism
Response 574 of 997: Marcia (MarciaH) * Tue, Aug 28, 2001 (22:52) * 5 lines
http://www.lightweb.com/stainedglass.htm
Topic 2 of 99 [Geo]: Vulcanism
Response 575 of 997: Marcia (MarciaH) * Thu, Aug 30, 2001 (19:07) * 9 lines
My son informed me he and his fiancee are off to see the Lava Beds National Park. I wonder that he has not seen enough lava beds in his lifetime?! He spent 22 years of his life on them!
http://www.nps.gov/labe/
http://www.gorp.com/gorp/resource/us_NM/ca_lava.htm
http://www.ecst.csuchico.edu/~beej/lavabeds/lavabeds.html
http://www.aqd.nps.gov/grd/parks/labe/
http://vulcan.wr.usgs.gov/Volcanoes/MedicineLake/Locale/framework.html
Topic 2 of 99 [Geo]: Vulcanism
Response 576 of 997: Marcia (MarciaH) * Fri, Aug 31, 2001 (17:11) * 171 lines
USGS Volcano News 8-31-2001 Hawaii and Alaska
Volcano Watch - August 30, 2001
Ozone in our air - friend or foe? - depends on where
Several decades ago, a person who had an overly active imagination might
have been described as being "out in the ozone." Now just where would that
be? Well, ozone (O3) exists in two distinct layers in the Earth's
atmosphere and is considered "good" or "bad," depending on where it is. The
US EPA has coined a maxim to help us remember: "good up high - bad nearby."
The atmospheric layer where we live is known as the troposphere and extends
from the surface of the Earth up to about 6 miles (10 km). Ozone in this
layer is a bad pollutant; vehicles, power plants and factories emit air
pollution that forms ground level O3. Ozone is a major component of urban
smog and damages human health, vegetation, and many common materials like
rubber, cloth, and paint. Although O3 concentrations on the Island of
Hawai'i are generally very low, certain areas in urban Honolulu do
occasionally exceed state health standards.
In contrast, "good" ozone resides in the stratosphere, the
atmospheric layer that extends upward from about 6 to 30 miles (10 - 50
km). When traveling in a commercial jet, you are at the base of the
stratosphere. Stratospheric O3 is important for protecting life on earth by
absorbing much of the harmful ultraviolet sunlight radiation known as UV-B.
Increases in UV-B exposure can lead to more cases of skin cancer,
cataracts, and impaired immune systems. Also, damage to UV-B sensitive
crops, such as soybeans, and marine organisms, could reduce food supplies.
Although ozone in the stratosphere is naturally produced and
destroyed at a constant rate, humans are gradually tipping the balance by
using ozone-depleting substances. The chemicals used in refrigerators, air
conditioners, fire extinguishers and solvents can reach the stratosphere,
where they are broken down and release chlorine and bromine molecules which
destroy "good" O3. One chlorine or bromine molecule can destroy 100,000
ozone molecules, so O3 in the stratosphere is disappearing much faster than
nature can replace it. Interestingly, explosive volcanoes contribute a
minor amount of chlorine to the stratosphere- about 3 percent of the total,
while humans contribute 82 percent. Gases from quieter eruptions, such as
the current one at Kilauea, do not reach and affect stratospheric ozone.
The Hawaiian Volcano Observatory, through a cooperative project with the
National Park Service and US EPA, measures the column of O3 between the
ground and the sun, as well as the amount of harmful UV-B getting through
to the Earth's surface. Data are collected using a sensitive
spectrophotometer that carefully measures light of specific wavelengths.
The HVO site is part of a nationwide network that is examining the effects
of UV-B on the health of humans and other species. The network also
contributes to an international effort to track the global distribution of
stratospheric O3 depletion. At HVO this instrument also measures sulfur
dioxide (SO2) and nitrogen dioxide (NO2), two gases that are released
during and after lava is erupted.
The Earth's atmosphere is a fragile layer which protects life on earth from
the damaging radiation from the sun. If the Earth were the size of soccer
ball, then a layer of plastic food wrap around the ball would represent the
troposphere, where we live. The stratosphere, where the good O3 resides,
would be an additional 4 layers of plastic wrap. The good news is that
there are things that we can all do to help keep the thin, fragile layers
of our atmosphere healthy- so that we too can remain healthy. To learn how
you can help minimize the production of "bad" O3 and help protect the
"good" stratospheric ozone layer, check out the following web site:
http://www.epa.gov/oar/oaqps/gooduphigh/#what
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u `O`o
vent during the past week. Lava moves away from the vent toward the ocean
in a network of tubes and descends Pulama pali in two separate areas. Lava
continued to enter the ocean in the area east of Kupapa`u throughout the
week and provided visitors to the viewing area a great show. On August 30,
a small surface flow, originating from a breakout of the tube supplying the
ocean entry, was within 150 m (500 ft) of the road leading to the viewing
area. As a precautionary measure, the County closed the road. USGS
personnel from HVO will continue to monitor the progress of the flow and
will keep the County officials informed.
The public is reminded that the bench of the ocean entry area is
extremely hazardous, with possible collapses of the new land. The steam
cloud is extremely hot, highly acidic, and laced with glass particles.
Swimming at the black sand beach of the bench can be a blistering or even
deadly venture.
There were no earthquakes reported felt during the week ending on
August 30, 2001.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
U.S. Geological Survey
Hawaiian Volcano Observatory
PO Box 51, Hawaii National Park, HI 96718
Phone (808) 967-7328 FAX (808) 967-8890
Kamchatkan Volcanic Activity
INFORMATION RELEASE 54-01
Friday, August 31, 2001, 13:22 KDT (00:22 UTC)
The following Release was received by the Alaska Volcano Observatory
via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity was above background this past week. Weak shallow
earthquakes within the volcano's edifice were recorded. A series of weak
local shallow seismic signals (possible short-lived explosions) was
registered on August 24. From 17:00 KDT (04:00 UTC) on August 24 continuous
spasmodic volcanic tremor up to 0.20× 10(superscript: -6 )mps began to
recorded. The volcanic tremor amplitude was, on average, 0.20× 10
(superscript: -6 )mps on August 25. On August 26 continuous spasmodic
volcanic tremor decreased to 0.15× 10(superscript: -6 )mps. After - on
August 27-28 - the tremor amplitude increased, on average, to 0.19× 10
(superscript: -6 )mps and on August 29 it again increased, on average, to
0.38× 10(superscript: -6 )mps. On August 30 continuous spasmodic volcanic
tremor amplitude was, on average, 0.50× 10(superscript: -6 )mps. According
to seismic data, at 00:42 and 08:20 KDT on August 31 (11:42 and 19:20 UTC
on August 30) possible short-lived ash explosions rose 1,500-2,000 m above
the dome of the volcano.
Observers in Klyuchi town reported that a gas and steam plume rose 300 m
above the dome (2,750 m; 9,100 ft. ASL) and extended 40 km to the southeast
at 08:15 KDT on August 25 (19:15 UTC on August 24). At 17:20 KDT (04:20
UTC) on August 25, at 09:15 KDT on August 27 (20:15 UTC on August 26) and
at 20:30 KDT (07:30 UTC) on August 28 gas and steam plumes rose 100-300 m
above the dome (2,550-2,750 m; 8,400-9,100 ft. ASL). At other times, clouds
obscured the volcano.
A satellite image, at 07:20 KDT on August 25 (18:20 UTC on August 24),
showed a 4-pixel thermal anomaly (38.3 degrees C in a background 5 degrees
C) at the active dome area. A 2-pixel thermal anomaly was seen in an image
at 06:59 KDT on August 27 (17:59 UTC on August 26).
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels this past week. On August 25 the
volcano was quiet. On August 28-29 and 30, gas and steam plumes rose 50-100
m above the crater (4,800-4,850 m, 15,800-16,000 ft. ASL). At other times,
clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels this past week. Observers in
Kozirevsk village reported that at 08:00 KDT on August 25 (19:00 UTC on
August 24) a gas and steam plume rose 50 m above the dome (2,950 m, 9,700
ft. ASL) and extended to the east. On August 27-28 the volcano was quiet.
At other times, clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky volcano was at background levels. No seismicity on
August 25, 27-28 was registered under Koryaksky volcano and no data was on
August 29. The volcanoes were quiet this past week.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
No seismicity on August 28-29 was registered under the volcanoes. At other
times, seismic activity was at background levels. The volcanoes were quiet
this past week.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Topic 2 of 99 [Geo]: Vulcanism
Response 577 of 997: Marcia (MarciaH) * Sat, Sep 1, 2001 (20:50) * 23 lines
Advancing lava flow keeps visitors away
KALAPANA, Hawaii Gary and Connie MacLeod of Kailua were ready to fly to the Big
Island for some lava viewing yesterday when they learned the lava access road had been
closed because of an approaching flow.
They boarded the plane anyway, knowing they were going to miss the show.
"Bummer," said Gary MacLeod, stopped at a police roadblock.
County officials were expecting an updated report on the flow this morning. As of yesterday,
its speed had slowed as the flow widened to about 150 feet in a low spot about 200 feet
inland from the gravel access road, said Hawaiian Volcano Observatory scientist Arnold Okamura.
Little damage was expected to the road since the terrain will keep the flow in a narrow stream in the crossing point, Okamura said.
The flow is being fed by a surface outbreak from an underground lava tube. The surface
outbreak appeared to draw off lava that had been going to the sea, and little or no steam was
visible at the shore yesterday.
The steam had been the principal attraction to viewers, since only brief glimpses of red lava
were possible at the water's edge.
Yesterday morning, cars were arriving at the rate of about one every five to 10 minutes at the
police roadblock at the end of the pavement on Highway 130.
Officer Tom Letulle was doing his best to keep people from feeling the drive from Hilo was a
loss by suggesting they drive back by way of the scenic "Red Road" along the Puna coast.
more and fantastic photo... http://starbulletin.com/2001/09/01/news/story8.html
Topic 2 of 99 [Geo]: Vulcanism
Response 578 of 997: Paul Terry Walhus (terry) * Sun, Sep 2, 2001 (09:28) * 3 lines
That's awesome Marci, did you see the lava flow first hand? Can you bottle up some of that and send it to us in some lamps? Did you get your mug yet?
(I'm checking up to see if my fulfillment house is working).
Topic 2 of 99 [Geo]: Vulcanism
Response 579 of 997: Marcia (MarciaH) * Sun, Sep 2, 2001 (14:07) * 5 lines
Mug is not here yet. In Hilo everything goes to Honolulu first where they all take turns trying to break it. If they don't succeed, they send it on to me. I'll let you know as soon as I receive it.
I have seen many lava flows up close - or as close as you can get to 2000° F (1093°C) It is actually so hot there is physical wall of heat radiating so strongly that great effort must be made using some sort of shield to get close enough to get molten lava on your rock hammer. I think I have a picuture of David doing just that as a blob is about to encase his boots. Tell me how to get it to you and in what container and you can try adding it to your lamp.
I think the oil and salt or two low temperature melt oils might work better.
Actually, lava stays very hot for a long time after is has turned black. One Thanksgiving while the rest of America was burning themselves on hot turkey, I was out hiking to the active flow front. I found a recent specimen and picked it up to see if it differed from other flows. It was SO HOT I could not drop it fast enough and ended up with sore fingers for a while.
Topic 2 of 99 [Geo]: Vulcanism
Response 580 of 997: Marcia (MarciaH) * Sun, Sep 2, 2001 (14:10) * 1 lines
Nope, did not get to the new road while it was still accessable. Unhappily, a narrow and treacherous road has to be traversed to get there and the crazies who have to go 70 mph on it seem to smash into innocent drivers with great regularity out there. We were waiting for the crush of people to die down. You could tell by the article that we do NOT run away from our eruptions. I always hurry to see the latest offerings of Madame Pele. It is always spectacular!
Topic 2 of 99 [Geo]: Vulcanism
Response 581 of 997: Marcia (MarciaH) * Sun, Sep 2, 2001 (15:34) * 14 lines
Rob posted this link in
Yellowstone Volcano: Is "the Beast" Building to a Violent Tantrum?
When the volcano in Yellowstone National Park
blew 6,400 centuries ago, it obliterated a mountain
range, felled herds of prehistoric camels hundreds of
miles away and left a smoking hole in the ground the
size of the Los Angeles Basin.
Modern Yellowstone doesn't dwell on its
cataclysmic past—or its potential for another
monster eruption.
more... http://news.nationalgeographic.com/news/2001/08/0828_wireyellowstone.html
Topic 2 of 99 [Geo]: Vulcanism
Response 582 of 997: Marcia (MarciaH) * Sun, Sep 2, 2001 (15:35) * 3 lines
Rob posted it in... http://clubs.yahoo.com/clubs/worldvolcanism
Sorry Dear, I hit the submit button before I realized I had not put your link in.
Topic 2 of 99 [Geo]: Vulcanism
Response 583 of 997: Marcia (MarciaH) * Tue, Sep 4, 2001 (18:40) * 308 lines
GVP/USGS Weekly Volcanic Activity Report 22-28 August 2001
New Activity/Unrest: | Makian, Indonesia |
Ongoing Activity: | Etna, Italy | Karangetang, Indonesia | Kerinci,
Indonesia | Kilauea, USA | Lokon-Empung, Indonesia | Mayon, Philippines |
Merapi, Indonesia | Popocatépetl, México | Shiveluch, Russia | Soufrière
Hills, Montserrat | Tungurahua, Ecuador | Villarrica, Chile |
New Activity
MAKIAN Halmahera, Indonesia 0.32°N, 127.40°E; summit elev. 1,357 m
VSI stated that last week’s report of volcanic activity at Makian on 16
August was false. An observer mistook the glow from a bush fire as volcanic
activity.
Background. Makian volcano forms a 10-km-wide island near the southern end
of a chain of volcanic islands off the W coast of Halmahera and has been
the source of infrequent, but violent eruptions that have devastated
villages on the island. The large 1.5-km-wide summit crater, containing a
small lake on the NE side, gives the peak a flat-topped profile. Two
prominent valleys extend to the coast from the summit crater on the N and E
sides. Four parasitic cones are found on the western flanks. Eruption have
been recorded since about 1550; major eruptions in 1646, 1760-61, 1861-62,
1890, and 1988 caused extensive damage and many fatalities.
Sources: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html,
Darwin VAAC http://www.bom.gov.au/info/vaac/advisories.shtml
Makian Reports <
http://volcano.si.edu/gvp/volcano/region06/halma/makian/var.htm> from the
monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
Volcanic activity was relatively low at Etna during the week. Degassing and
seismic activity continued at Etna’s summit craters.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Source: Charles Rivière’s web site
http://perso.club-internet.fr/rivierec/aout_2001.htm
Etna Reports
from
the monthly Bulletin of the Global Volcanism Network
KARANGETANG [Api Siau] Siau Island, Indonesia 2.47°N, 125.29°E; summit
elev. 1,784 m
During 30 July-12 August seismic activity at Karangetang was dominated by
explosion, avalanche, and multiphase earthquakes. A steam-and-ash plume
rose to 600 m above the volcano. During 1-12 August lava flows and lava
avalanches were rarely observed. On 10 August cold lahars crossed roads as
they traveled down the Batu Awang River and the Kahetang River. The volcano
was at Alert Level 3 (on a scale of 1-4).
Background. Karangetang (also known as Api Siau) lies at the northern end
of the island of Siau, N of Sulawesi, and contains five summit craters
strung along a N-S line. One of Indonesia's most active volcanoes,
Karangetang has had more than 40 recorded eruptions since 1675.
Twentieth-century eruptions have included frequent explosions, sometimes
accompanied by pyroclastic flows and lahars.
Source: Volcanological Survey of Indonesia
Karangetang Reports
from the monthly Bulletin of the Global Volcanism Network
KERINCI Sumatra, Indonesia 1.69°S, 101.27°E; summit elev. 3,805 m
On 9 August a small explosion at Kerinci produced an ash cloud that rose
700 m above the summit. Workers in rice fields around the volcano heard a
booming sound and VSI personnel saw the dark brown ash cloud drift to the
NNE. During 30 July-12 August seismographs recorded 990 small explosion
events. The volcano was at Alert Level 2.
Background. The summit of 3800-m-high Kerinci, Indonesia's highest volcano,
contains a deep 600-m-wide crater often partially filled by a small crater
lake. The massive 13 x 25 km wide volcano towers 2400-3300 m above
surrounding plains. Kerinci is elongated in a N-S direction and is capped
by an unvegetated young summit cone constructed NE of an older crater
remnant. One of Sumatra's most active volcanoes, Gunung Kerinci has
produced a series of moderate explosive eruptions during the 19th and 20th
centuries.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Kerinci Reports
from the Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava continued to flow down the Pulama pali, and into the ocean at the E
Kupapa`u entry. On 25 August a small amount of sharp, short-lived inflation
occurred at Pu`u `O`o cone and an hour later at Kilauea’s summit. No change
in volcanic or seismic activity accompanied the inflation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
LOKON-EMPUNG northern Sulawesi, Indonesia 1.36°N, 124.79°E; summit elev.
1,580 m
VSI reported that there was a significant decrease in seismic activity at
Lokon during 30 July-12 August in comparison to during previous weeks.
Small explosions at Tompaluan crater produced plumes that rose 25-250 m
above the summit. The volcano remained at Alert Level 2 (on a scale of 1-4).
Background. The twin volcanoes Lokon and Empung, rising about 800 m above
the plain of Tondano, are among the most active volcanoes of Sulawesi.
Lokon, the higher of the two peaks (whose summits are only 2.2 km apart)
has a flat, craterless top. The morphologically younger Empung volcano has
a 400-m-wide, 150-m-deep crater that erupted last in the 18th century, but
all subsequent eruptions have originated from Tompaluan, a 150 x 250 m wide
double crater situated in the saddle between the two peaks. Historical
eruptions have primarily produced small-to-moderate ash plumes that have
occasionally damaged croplands and houses, but lava-dome growth and
pyroclastic flows have also occurred.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Lokon-Empung Reports <
http://www.nmnh.si.edu/gvp/volcano/region06/sulawesi/lokon/var.htm> from
the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
Volcanic activity remained low at Mayon during 22-28 August. There was
relatively little seismic activity, slight inflation, occasional
observations of incandescence at the summit, and a moderate amount of steam
emitted from the volcano. SO2 emission rates remained well above the
baseline value of 500 metric tons per day. PHIVOLCS reminded residents
along the banks of major channels that lahars and torrential stream flows
during heavy rains could remobilize material from pyroclastic-flow
deposits. The volcano remained at Alert Level 3.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Source: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
Mayon Reports
from
the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
During 30 July-12 August lava avalanches traveled towards the SW, extending
a maximum distance of 2.8 km down the Sat, Senowo, Lamat, and Bebeng
Rivers. Seismic activity was dominated by avalanche earthquakes. The
volcano remained at Alert Level 2 (on a scale of 1-4).
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Merapi Reports
from
the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m
Volcanic activity remained relatively low at Popocatépetl, with small
emissions of steam, gas, and minor amounts of ash.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
Seismic activity was above background levels during the week. Spasmodic
volcanic tremor and weak, shallow seismic signals (possible collapses and
avalanches) were registered. Several small explosions produced
gas-and-steam plumes that rose to a maximum height of 2 km above the dome.
Pyroclastic flows traveled down the flanks of the volcano following an
explosion on 23 August. Thermal anomalies were visible on satellite
imagery. Shiveluch remained at Concern Color Code <
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm> Orange.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev.
1,030 m; All times are local (= UTC 4 hours)
Volcanic activity at Soufrière Hills remained at a similar level as the
previous week, except for an increase in hybrid seismic events. Rockfalls
and pyroclastic flows observed in the upper reaches of the Tar River Valley
appeared to originate from the new dome, which was obscured by
meteorological clouds. After 22 August, banded tremor that had increased
the previous week declined to low levels. The Washington VAAC reported that
an ash emission occurred on 26 August at 1215, rose to ~2 km, and drifted
to the SW.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvo.ms/, Washington VAAC
http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
The Washington VAAC reported that nearly continuous ash emissions had
occurred at Tungurahua since 6 August, but extensive cloudiness prohibited
ash-cloud detection in satellite imagery. According to the Guayaquil MWO, a
new eruption on 24 August at 1755 produced an ash cloud that rose to ~6 km
and drifted E to SE. The same day IG reported that ash was emitted to 6-7.6
km.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
from the monthly Bulletin of the Global Volcanism Network
VILLARRICA central Chile 39.42°S, 71.93°W; summit elev. 2,847 m
On 9, 16, 17, and 21 August volcanic ballistic clasts were observed falling
near the WSW edge of the crater. In addition, observations of the volcano
on 22 August revealed that the lava lake had risen 40 m since 9 August.
Background. Villarrica, one of Chile's most active volcanoes, rises above
the lake and town of the same name. It is the westernmost of three large
stratovolcanoes that trend perpendicular to the Andean chain. A 6-km wide
caldera formed during the late Pleistocene, more than 0.9 million years
ago. A 2-km-wide postglacial caldera is located at the base of the
presently active, dominantly basaltic-to-andesitic cone at the NW margin of
the Pleistocene caldera. About 25 scoria cones dot Villarica's flanks.
Plinian eruptions and pyroclastic flows have been produced during the
Holocene from this dominantly basaltic volcano, but historical eruptions
have consisted largely of mild-to-moderate explosive activity with
occasional lava effusion. Lahars from the glacier-covered volcano have
damaged towns on its flanks.
Source: Villarrica Volcano Visual Surveillance Project http://www.povi.org/
Villarrica Reports
from the monthly Bulletin of the Global Volcanism Network
Topic 2 of 99 [Geo]: Vulcanism
Response 584 of 997: Marcia (MarciaH) * Thu, Sep 6, 2001 (16:20) * 18 lines
From Rob... this has been on the news all morning here:
Philippines Begins Draining Volcano Crater-Lake
BOTOLAN, Philippines (Reuters) - The Philippines began draining water from the swollen crater-lake of the Pinatubo
volcano on Thursday in an effort to save a nearby town from being swamped by floods.
``The operation started at 6:53 a.m. (6:53 p.m. EDT Wednesday) and the waters are flowing out gently,'' vulcanologist
Jim Siosoco told Reuters. ``We are doing it slowly.''
As a precaution, local officials evacuated thousands of residents from Botolan town, 25 miles from the volcano, a day
before the massive, state-supervised operation was to begin, in case the released waters hit the town.
There has been no indication of any overspill of the released water so far.
Hundreds of families living in the town center have refused to leave, fearing looters would break into their homes.
http://us.f206.mail.yahoo.com/ym/ShowLetter?YY=83990&order=up&sort=date
Topic 2 of 99 [Geo]: Vulcanism
Response 585 of 997: Marcia (MarciaH) * Thu, Sep 6, 2001 (21:15) * 14 lines
Kilauea Update 0520 September 6, 2001
The same flow active for the past several days is advancing down Pulama pali this morning at 0443. Three sections are incandescent, spanning the distance from the top of the pali to the base. Trees are burning in the middle section, about 1/3 of the way down the pali. The flow is in the eastern part of the flow field.
The East Kupapa`u entry is active, though glow is subdued by heavy steam.
The flow across the new access road had definitely stopped by yesterday, and road crews were busy putting crushed rock across it in preparation for reopening the road.
There is a large reservoir of lava on the coastal flat contained within inflating flows. Breakouts will occur from this reservoir from time to time; the one that crossed the road is an example.
The crater of Pu`u `O`o is dark this morning, socked in by the heavy fume.
Volcanic tremor remains at a moderate to low level at both Kilauea's summit and Pu`u `O`o. Currently all tiltmeters on the volcano are showing normal trends.
Topic 2 of 99 [Geo]: Vulcanism
Response 586 of 997: Marcia (MarciaH) * Fri, Sep 7, 2001 (16:27) * 86 lines
Kilauea Volcano Watch - September 6, 2001
Lava covers road: expectable as the eruption continues
Nothing is constant except change. On August 17 the Kalapana road was
reopened, allowing visitors access to a short trail and fine view point
overlooking the active ocean-entry bench. Two weeks later, a narrow lava
flow crossed the road just east of the trailhead, and the road was closed.
How did this happen, will it happen again, and what can be done about it?
Lava has been flowing continuously over Pulama pali through as many
as three tubes since last spring. Some of this lava moves underground
through the tube system to the coast, feeding the large and persistent
ocean entry just east of Kupapa`u. Much of the lava, however, does not make
it that far, instead breaking out from the tubes far inland and forming
surface flows.
On almost every day for the past few months, several lava flows have
been active on the coastal flat between the shoreline and the base of
Pulama pali. Most of the flows do not advance to the coast but pool on the
surface farther inland. Often the result is a thick sheet of pahoehoe that
inflates to several times its original thickness as lava lifts up the
surface crust of the flow. Lava can break out of such an inflating flow and
feed smaller surface flows.
Some of these surface flows reach seaward from the area of
large-scale inflation. Throughout the spring and early summer, the rough,
bulldozed road along the former route of Highway 130 was repeatedly
shortened as lava flows moved across it. Currently the roadway is 1.4 km
(0.8 miles) shorter than it was in February. During April and May alone, 1
km (0.6 miles) of the road was covered.
The latest in this series of flows is the narrow tongue of lava that
crossed the refurbished road on the night of September 1. Neither the flow
itself nor its timing is unusual; lava simply happened to ooze across the
road at an inopportune time. The front of the flow is only 70 m (yards)
beyond the road. Had the flow stopped short of the road, it would have
caused a lot less grief.
Now that the road has been reopened, we have to think about the
future. Will something like this happen again? The answer is easy:
certainly, as long as the eruption continues. What can be done about it?
This answer is also easy: nothing. There is no stopping the lava from going
where it wants across the existing flow field.
There could be long spells without surface flows anywhere near the
road, however. The flows might stop following a pause in the eruption, if
the tube becomes plugged above the pali so that lava is no longer supplied
to the coastal flat. The flows that threaten the road might also stop if
the tube system changes location, as is likely following a long pause. A
new tube system could be developed farther west, shutting off the current
ocean entry and sending all, or most, of the lava back into the park. We
would then have to wait for an eastward shift in the tube system before
seeing lava again in the Kupapa`u area.
Meanwhile, you can enjoy the closeness of the lava to the road.
Whether you see the colorful ocean entry, or lava oozing across the ground
surface, or both, you are in for a treat possible nowhere else in the world
with such ease and safety. And, while driving along the access road, be
sure to look for the site where the opening scene of Planet of the Apes II
was filmed. Note the fence posts that were surrounded by lava flows and
raised up 6-9 m (20-30 feet) as the flows inflated. Quietly remember that
the desolate roadway was once lined with the homes of Kalapana.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week. Lava moves away from the vent toward the
ocean in a network of tubes and descends Pulama pali in separate areas. A
surface flow, cascading down the eastern section of the pali, was observed
throughout the week. Lava continued to enter the ocean in the area east of
Kupapa`u. The small surface flow reported last week, crossed the road
leading to the viewing area on the night of September 1 and stagnated to a
halt after traveling 70 m (200 ft) past the road. The County has repaired
the road and reopened it to the public. USGS personnel from HVO will
monitor the area and keep the County officials informed of any change in
lava flow activity.
The public is reminded that the bench of the ocean entry area is
extremely hazardous, with possible collapses of the new land. The steam
cloud is extremely hot, highly acidic, and laced with glass particles.
Swimming at the black sand beach of the bench can be a blistering or even
deadly venture.
One earthquake was reported felt during the week ending on September
6, 2001. A resident of Volcano and a resident of Papa`aloa felt an
earthquake at 3:07 a.m. on Tuesday, September 4. The magnitude-3.6
earthquake was located 8 km (4.8 mi) southwest of the summit of Kilauea
Volcano at a depth of 27.55 km (16.5 mi).
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
U.S. Geological Survey
Hawaiian Volcano Observatory
PO Box 51, Hawaii National Park, HI 96718
Topic 2 of 99 [Geo]: Vulcanism
Response 587 of 997: Marcia (MarciaH) * Sat, Sep 8, 2001 (13:14) * 42 lines
*********************************************************
Montserrat Volcano Observatory: Weekly Activity Report
*********************************************************
From: Peter Dunkley
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 31 August 2001 to midday, 7 September 2001
Activity at the Soufrière Hills Volcano continued at similar levels to
the previous week. The seismograph network recorded 218 rockfall
signals, 31 long period events, 2 long period rockfalls, 8 hybrid events
and 4 volcanotectonic earthquakes.
Bands of tremor continued at irregular intervals, and were associated
with increased rockfall activity and venting of ash. During the
reporting period they occurred with an average periodicity of about 17
hours.
The active lava dome was clearly seen on a number of occasions and
appears to be growing rapidly. This is now a well-formed, steep-sided
dome with a rugged summit area. On the night of the 3 September, the
dome was seen glowing incandescently from the vantage point on Jackboy
Hill. Rock falls and small pyroclastic flows originating from the dome
were observed in the upper reaches of the Tar River Valley.
Sulphur dioxide fluxes of 242 tonnes per day and 86 tonnes per day were
measured with the correlation spectrometer on 31 August and 1 September
respectively.
The daytime entry zone (DTEZ) remains open. Activity could increase
quite suddenly, with a dangerous situation developing very quickly. Ash
masks should be worn in ashy conditions. The Belham Valley should be
avoided during and after heavy rainfall due to the possibility of
mudflow activity.
Residents of Montserrat and visitors to the island are advised to tune
into ZJB Radio for up-to-date information on the volcano. Access to
Plymouth, Bramble airport and beyond is prohibited. There is a maritime
exclusion zone around the southern part of the island that extends two
miles beyond the coastline from Trant's Bay in the east to Garibaldi
Hill on the west coast.
12 noon, Friday, 7 September 2001
Peter Dunkley
Montserrat Volcano Observatory
Mongo Hill
Montserrat
West Indies
Topic 2 of 99 [Geo]: Vulcanism
Response 588 of 997: Marcia (MarciaH) * Sat, Sep 8, 2001 (13:17) * 54 lines
For the week prior to the one above:
********************************************************
Montserrat Volcano Observatory - Weekly Activity Report
********************************************************
From: Peter Dunkley
Montserrat, W.I.
Report for the period midday, 24 August 2001 to midday, 31 August 2001
Activity at the Soufrière Hills Volcano continued at similar levels to
the previous week. The seismograph network recorded 200 rockfall
signals, 6 long period events, 1 long period rockfall, 19 hybrid events
and 11 volcanotectonic earthquakes.
Bands of tremor continued at intervals of between 13 and 27 hours. This
signal has been recorded since the 29th July collapse, and is indicative
of rapid magma ascent. During these tremor bands, rockfall activity
increases and venting of ash sometimes occurs. One particularly vigorous
period of ash-venting occurred at midday on Sunday 26th August. This
lasted for an hour and produced a series of heavily laden ash pulses
which rose to about 7000 feet and were carried westwards out to sea on
the prevailing wind. This venting coincided with a discrete band of
tremor.
A weak swarm of volcanotectonic earthquakes began on 29th August and is
continuing at a diminished level. These earthquakes have low magnitudes
(of less than 1) and therefore cannot be located accurately.
The new lava dome was seen clearly on the afternoon of 24th August and
the morning of 28th August. This now has a well-formed dome-like
morphology and appears to be growing rapidly in the scar produced by the
29th July collapse. Rock falls and small pyroclastic flows originating
from the new dome were observed in the upper reaches of the Tar River
Valley.
Sulphur dioxide fluxes of 68 tonnes per day and 151 tonnes per day were
measured with the correlation spectrometer on 25th and 28th of August
respectively. Trials were also conducted using a new instrument for
monitoring sulphur dioxide. The instrument, known as a Differential
Optical Absorption Spectrometer (DOAS), gave very similar results to
those measured by the correlation spectrometer.
The daytime entry zone (DTEZ) was re-opened on 29 August. Activity
could increase quite suddenly, with a dangerous situation developing
very quickly. Ash masks should be worn in ashy conditions. The Belham
Valley should be avoided during and after heavy rainfall due to the
possibility of mudflow activity.
Residents of Montserrat and visitors to the island are advised to tune
into ZJB Radio for up-to-date information on the volcano. Access to
Plymouth, Bramble airport and beyond is prohibited. There is a maritime
exclusion zone around the southern part of the island that extends two
miles beyond the coastline from Trant's Bay in the east to Garibaldi
Hill on the west coast.
12 noon, Friday, 31 August 2001
Peter Dunkley
Montserrat Volcano Observatory
Mongo Hill
Montserrat
West Indies
Topic 2 of 99 [Geo]: Vulcanism
Response 589 of 997: Marcia (MarciaH) * Sat, Sep 8, 2001 (13:24) * 182 lines
************************************
KVERT Information Release 55-01,
September 7, 2001
************************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 55-01
Friday, September 07, 2001, 14:02 KDT (01:02 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity was above background levels this past week. Many weak
shallow earthquakes within the volcano's edifice and series of weak local
shallow seismic signals (possible short-lived explosions) were registered
the entire week. From August 31 until September 2 a continuous spasmodic
volcanic tremor was recorded. The volcanic tremor amplitude was, on
average, 0.59× 10(superscript: -6 )mps on August 31 and 0.34× 10
(superscript: -6 )mps on September 1. An intermittent spasmodic volcanic
tremor was registered on September 3-5. The tremor amplitude increased, on
average, from 0.24× 10(superscript: -6 )mps on September 3 to 0.27× 10
(superscript: -6 )mps on September 5. One MI>=2 earthquake was registered
on September 4.
Observers in Klyuchi town reported that a gas and steam plume rose 600 m
above the dome (3,050 m; 10,100 ft. ASL) at 21:30 KDT (08:30 UTC) on August
31. At 08:30 KDT on September 3 (19:30 UTC on September 2) and at 17:05 KDT
(04:05 UTC) on September 5 gas and steam plumes rose 100 and 300 m above
the dome (2,550 and 2,750 m; 8,400 and 9,100 ft. ASL). At 08:45 KDT on
September 4 (19:45 UTC on September 3) a gas and steam plume rose 1,200 m
above the dome (3,650 m; 12,050 ft. ASL) and extended 10 km to the east.
According to visual data from Klyuchi town, at 09:20 KDT on September 4
(20:20 UTC on September 3) explosions sent an ash plume 1,000 m above the
dome (3,450 m; 11,400 ft. ASL) and short pyroclastic flow 1 km long to the
southeast. At other times, clouds obscured the volcano.
A satellite image, at 06:40 KDT on August 31 (17:40 UTC on August 30),
showed a 2-pixel thermal anomaly (3.8 degrees C in a background -7 degrees
C) at the active dome area. Possible a gas-steam plume ~80-km-long
extending to the east from volcano was seen in an image at 13:32 KDT (00:31
UTC) on August 31. Satellite images showed a 2-pixel thermal anomaly at the
volcano on September 3, 5 and 6. At 07:09 KDT (20:09 UTC) on September 3
the thermal anomaly was 35.9 degrees C in a background -2 degrees C; at
18:29 KDT (05:29 UTC) on September 5 it was 49.5 degrees C in a background
-5 degrees C; at 18:17 KDT (05:17 UTC) on September 6 it was 37.8 degrees C
in a background 3 degrees C.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels this past week. On September 5-7
the volcano was quiet. At other times, clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels on August 31 and September 2. At
other times, no seismicity was registered under the volcano. Observers in
Kozirevsk village reported that on September 4 gas and steam plumes rose
100-500 m above the dome (3,000-3,400 m, 9,900-11,200 ft. ASL) and extended
10-15 km to the
south. A weak fumarolic activity was observed at the volcano on September
3, 5 and 6. At other times, clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity at Avachinsky volcano was above background levels on
August 31. Two MI>=2 and one MI>=1.7 earthquakes were registered. At other
times, seismicity volcano was at background levels. Seismicity at Koryaksky
volcano was at background levels on September 2 and 4, but no seismicity
was registered under the volcano at all other times. The volcanoes were
quiet on September 3-6. At other times, clouds obscured the volcanoes.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
Seismicity at Gorely volcano was at background levels on September 3-4. At
other times, no seismicity was registered under the volcano. Seismicity at
Mutnovsky
volcano was at background levels on September 1 and 4, but no seismicity
was registered under the volcano at all other times. The volcanoes were
quiet on September 5-6. At other times, clouds obscured the volcanoes.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006
RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
907-786-7497
************************************
KVERT Information Release 54-01,
August 31, 2001
************************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 54-01
Friday, August 31, 2001, 13:22 KDT (00:22 UTC)
The following Release was received by the Alaska Volcano Observatory
via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team).
All times are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity was above background this past week. Weak shallow
earthquakes within the volcano's edifice were recorded. A series of weak
local shallow seismic signals (possible short-lived explosions) was
registered on August 24. From 17:00 KDT (04:00 UTC) on August 24 continuous
spasmodic volcanic tremor up to 0.20× 10(superscript: -6 )mps began to
recorded. The volcanic tremor amplitude was, on average, 0.20× 10
(superscript: -6 )mps on August 25. On August 26 continuous spasmodic
volcanic tremor decreased to 0.15× 10(superscript: -6 )mps. After - on
August 27-28 - the tremor amplitude increased, on average, to 0.19× 10
(superscript: -6 )mps and on August 29 it again increased, on average, to
0.38× 10(superscript: -6 )mps. On August 30 continuous spasmodic volcanic
tremor amplitude was, on average, 0.50× 10(superscript: -6 )mps. According
to seismic data, at 00:42 and 08:20 KDT on August 31 (11:42 and 19:20 UTC
on August 30) possible short-lived ash explosions rose 1,500-2,000 m above
the dome of the volcano.
Observers in Klyuchi town reported that a gas and steam plume rose 300 m
above the dome (2,750 m; 9,100 ft. ASL) and extended 40 km to the southeast
at 08:15 KDT on August 25 (19:15 UTC on August 24). At 17:20 KDT (04:20
UTC) on August 25, at 09:15 KDT on August 27 (20:15 UTC on August 26) and
at 20:30 KDT (07:30 UTC) on August 28 gas and steam plumes rose 100-300 m
above the dome (2,550-2,750 m; 8,400-9,100 ft. ASL). At other times, clouds
obscured the volcano.
A satellite image, at 07:20 KDT on August 25 (18:20 UTC on August 24),
showed a 4-pixel thermal anomaly (38.3 degrees C in a background 5 degrees
C) at the active dome area. A 2-pixel thermal anomaly was seen in an image
at 06:59 KDT on August 27 (17:59 UTC on August 26).
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels this past week. On August 25 the
volcano was quiet. On August 28-29 and 30, gas and steam plumes rose 50-100
m above the crater (4,800-4,850 m, 15,800-16,000 ft. ASL). At other times,
clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels this past week. Observers in
Kozirevsk village reported that at 08:00 KDT on August 25 (19:00 UTC on
August 24) a gas and steam plume rose 50 m above the dome (2,950 m, 9,700
ft. ASL) and extended to the east. On August 27-28 the volcano was quiet.
At other times, clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at Avachinsky volcano was at background levels. No seismicity on
August 25, 27-28 was registered under Koryaksky volcano and no data was on
August 29. The volcanoes were quiet this past week.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
No seismicity on August 28-29 was registered under the volcanoes. At other
times, seismic activity was at background levels. The volcanoes were quiet
this past week.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Topic 2 of 99 [Geo]: Vulcanism
Response 590 of 997: Marcia (MarciaH) * Sat, Sep 8, 2001 (13:31) * 299 lines
GVP/USGS Weekly Volcanic Activity Report - 29 August-4 September 2001
Ongoing Activity: | Karangetang, Indonesia | Kerinci, Indonesia | Kilauea,
USA | Lokon-Empung, Indonesia | Mayon, Philippines | Merapi, Indonesia |
Pinatubo, Philippines | Popocatépetl, México | Rabaul, Papua New Guinea |
Shiveluch, Russia | Soufrière Hills, Montserrat | Tungurahua, Ecuador |
Ongoing Activity
KARANGETANG [Api Siau] Siau Island, Indonesia 2.47°N, 125.29°E; summit
elev. 1,784 m
During 13-26 August lava flowed ~1 km towards the Kehetang River, and ~1.6
km towards the Keting River. Avalanches that originated from the edges of
the lava flows traveled up to 1.5 km. Seismicity was dominated by small
explosion, avalanche, and multiphase earthquakes. The volcano remained at
Alert Level 3 (on a scale of 1-4).
Background. Karangetang (also known as Api Siau) lies at the northern end
of the island of Siau, N of Sulawesi, and contains five summit craters
strung along a N-S line. One of Indonesia's most active volcanoes,
Karangetang has had more than 40 recorded eruptions since 1675.
Twentieth-century eruptions have included frequent explosions, sometimes
accompanied by pyroclastic flows and lahars.
Source: Volcanological Survey of Indonesia
Karangetang Reports
from the monthly Bulletin of the Global Volcanism Network
KERINCI Sumatra, Indonesia 1.69°S, 101.27°E; summit elev. 3,805 m
During 13-26 August eruptive activity ceased and seismic activity was
dominated by small explosion earthquakes (2,252). The volcano remained at
Alert Level 2 (on a scale of 1-4).
Background. The summit of 3800-m-high Kerinci, Indonesia's highest volcano,
contains a deep 600-m-wide crater often partially filled by a small crater
lake. The massive 13 x 25 km wide volcano towers 2400-3300 m above
surrounding plains. Kerinci is elongated in a N-S direction and is capped
by an unvegetated young summit cone constructed NE of an older crater
remnant. One of Sumatra's most active volcanoes, Gunung Kerinci has
produced a series of moderate explosive eruptions during the 19th and 20th
centuries.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Kerinci Reports
from the Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava continued to enter the sea at the E Kupapa`u entry. Surface lava flows
were visible on Pulama pali and the coastal flat. By 1 September a surface
lava flow that broke out of the ocean-entry tube on the coastal plain
during mid-August flowed across a County lava-viewing road. The unpaved
section of Highway 130 had been open for less than 2 weeks before the
narrow lava flow crossed it. Generally, volcanic tremor remained at
low-to-moderate levels at Kilauea’s summit and Pu`u `O`o. Tiltmeters across
the volcano showed no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Sources: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/, The Honolulu Advertiser.com
http://the.honoluluadvertiser.com/article/2001/Sep/03/ln/ln20a.html
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
LOKON-EMPUNG northern Sulawesi, Indonesia 1.36°N, 124.79°E; summit elev.
1,580 m: All times are local (= UTC + 9 hours)
On 18 August at 2230 an explosion produced an ash cloud that rose ~800 m
above the crater and drifted over the town of Manado 25 km N of the
volcano. Following the explosion there was a significant increase in
volcanic earthquakes in comparison to the previous week. The volcano
remained at Alert Level 2 (on a scale of 1-4).
Background. The twin volcanoes Lokon and Empung, rising about 800 m above
the plain of Tondano, are among the most active volcanoes of Sulawesi.
Lokon, the higher of the two peaks (whose summits are only 2.2 km apart)
has a flat, craterless top. The morphologically younger Empung volcano has
a 400-m-wide, 150-m-deep crater that erupted last in the 18th century, but
all subsequent eruptions have originated from Tompaluan, a 150 x 250 m wide
double crater situated in the saddle between the two peaks. Historical
eruptions have primarily produced small-to-moderate ash plumes that have
occasionally damaged croplands and houses, but lava-dome growth and
pyroclastic flows have also occurred.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Lokon-Empung Reports <
http://www.nmnh.si.edu/gvp/volcano/region06/sulawesi/lokon/var.htm> from
the monthly Bulletin of the Global Volcanism Network
MAYON southeastern Luzon, Philippines 13.257°N, 123.685°E; summit elev.
2,462 m
During the week seismicity was relatively low, SO2 emission rates were well
above the baseline value of 500 metric tons per day, the edifice was
slightly inflated, and steaming and incandescence were occasionally visible
at the crater. The volcano remained at Alert Level 3.
Background. The beautifully symmetrical Mayon volcano, which rises to 2,462
m above the Albay Gulf, is the Philippines' most active volcano. The
structurally simple volcano has steep upper slopes that average 35-40° and
is capped by a small summit crater. The historical eruptions of this
basaltic-andesitic volcano date back to 1616 and range from Strombolian to
basaltic Plinian. Eruptions occur predominately from the central conduit
and have also produced lava flows that travel far down the flanks.
Pyroclastic flows and mudflows have commonly swept down many of the
approximately 40 ravines that radiate from the summit and have often
devastated populated lowland areas. Mayon’s most violent eruption, in 1814,
killed more than 1,200 people and devastated several towns. Eruptions that
began in February 2000 led PHIVOLCS to recommend on 23 February the
evacuation of people within a radius of 7 km from the summit in the SE and
within a 6 km radius for the rest of the volcano.
Source: Philippine Institute of Volcanology and Seismology
http://www.phivolcs.dost.gov.ph/vmepd/vmepd.htm
Mayon Reports
from
the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
During 13-26 August approximately 380 lava avalanches were observed
travelling SW, extending a maximum distance of 2.8 km mainly down the Sat
and Lamat rivers, and to a lesser extent towards the Senowo and Bebeng
rivers. Seismic activity consisted primarily of avalanche earthquakes, as
it had for the previous 2 weeks. The volcano remained at Alert Level 2 (on
a scale of 1-4).
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Merapi Reports
from
the monthly Bulletin of the Global Volcanism Network
PINATUBO Luzon, Philippines 15.13°N, 120.35°E; summit elev. 1,486 m
Due to the threat of Pinatubo’s crater lake overflowing during draining
procedures, Philippine officials plan to evacuate ~40,000 residents of the
town of Botolan 40 km NW of Pinatubo’s crater to higher ground on 5
September. The crater lake is ~2.5 km wide, and contains ~210 million cubic
meters of water. According to a Guardian news article, water in the crater
rose to ~80 cm below the lowest point of the crater rim on 3 September. In
comparison, water was 1.5 m below the rim on 31 August, and 4.5 m below it
5 weeks earlier. On 6 September workers plan to remove a 5-m-large portion
of the crater’s wall that will cause the water to be released towards the N.
Background. Prior to 1991 Pinatubo volcano was a relatively unknown,
heavily forested lava dome complex located 100 km NW of Manila with no
records of historical eruptions. The 1991 eruption, one of the world's
largest of the 20th century, ejected massive amounts of tephra and produced
voluminous pyroclastic flows, forming a small, 2.5-km-wide summit caldera
whose floor is now partially filled by a lake. Although the eruption caused
hundreds of fatalities and severe social and economic impact, successful
monitoring efforts greatly reduced the number of fatalities. Widespread
lahars that redistributed products of the 1991 eruption have continued to
cause severe disruption. At least six major eruptive periods, separated by
lengthy quiescence, have occurred from modern Pinatubo volcano during the
past 40,000 years. Most of these have produced major pyroclastic flows and
lahars that were even more extensive than in 1991.
Sources: Australian Broadcasting Corporation
http://www.abc.net.au/ra/newsdaily/s357978.htm, Agence France-Presse
http://sg.news.yahoo.com/010904/1/1e4j8.html, The Guardian
http://www.guardian.co.uk/international/story/0,3604,546423,00.html
Pinatubo Reports
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m
Volcanic activity remained relatively low at Popocatépetl, with small
emissions of steam, gas, and minor amounts of ash.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
RABAUL New Britain Island, Papua New Guinea 4.271°S, 152.203°E; summit
elev. 688 m
On 28 August very mild ash eruptions began. The eruptions followed an
increase in the number and magnitude of low-frequency volcanic earthquakes
a few days earlier. Eruptions continued until at least 31 August.
Background. The low-lying Rabaul caldera on the tip of the Gazelle
Peninsula at the NE end of New Britain forms a broad sheltered harbor. The
outer flanks of the 688-m-high asymmetrical pyroclastic shield volcano are
formed by thick pyroclastic-flow deposits. The 8 x 14 km caldera is widely
breached on the E, where its floor is flooded by Blanche Bay.Two major
Holocene caldera-forming eruptions at Rabaul took place as recently as
3,500 and 1,400 years ago. Three small stratovolcanoes lie outside the
northern and NE caldera rims. Post-caldera eruptions built
basaltic-to-dacitic pyroclastic cones on the caldera floor near the NE and
western caldera walls. Several of these, including Vulcan cone, which was
formed during a large eruption in 1878, have produced major explosive
activity during historical time. A powerful explosive eruption in 1994
occurred simultaneously from Vulcan and Tavurvur volcanoes and forced the
temporary abandonment of Rabaul city.
Source: Rabaul Volcano Observatory via the Darwin VAAC
http://www.bom.gov.au/info/vaac/
Rabaul Reports
from the Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
Seismic activity was above background levels during 24-31 August. Weak
shallow earthquakes within the volcano’s edifice and signals that may have
represented short-lived explosions were recorded. Thermal anomalies were
visible on satellite imagery. Shiveluch remained at Concern Color Code <
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm> Orange.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
Activity at Soufrière Hills remained at similar levels as during the
previous weeks. Following the partial dome collapse on 29 July bands of
tremor, which indicate rapid magma ascent, occurred at 13-27 hour
intervals. During these banded-tremor events rockfall activity and ash
venting increased, sending ash up to ~2 km above the volcano, drifting to
the W. A weak swarm of volcano-tectonic earthquakes (less than M 1) began
on 29 August. Observations revealed that the new lava dome had a
well-formed dome-like morphology and appeared to have rapidly grown in the
scar produced by the 29 July collapse. Rockfalls and small pyroclastic
flows that originated from the new dome were observed in the upper reaches
of the Tar River Valley. The daytime entry zone was re-opened on 29 August.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvo.ms/
Soufrière Hills Reports
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m
Small emissions that contained minor amounts of ash took place during the
week. The highest ash cloud reported occurred on 3 September, rose to ~5.8
km, and drifted to the W.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
from the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Topic 2 of 99 [Geo]: Vulcanism
Response 591 of 997: Paul Terry Walhus (terry) * Sat, Sep 8, 2001 (21:22) * 1 lines
Montserrat is where the Beatles did a lot of recording.
Topic 2 of 99 [Geo]: Vulcanism
Response 592 of 997: Marcia (MarciaH) * Sat, Sep 8, 2001 (21:53) * 2 lines
Think it would not be possible now. Where they were isn't anymore, I think!
Poor Monserrat. So beautiful and so terrible at the same time!
Topic 2 of 99 [Geo]: Vulcanism
Response 593 of 997: Marcia (MarciaH) * Mon, Sep 10, 2001 (18:18) * 88 lines
**************************************
Indonesian Updates for 13-26 August
**************************************
For the period 13-26 August, the new eruption at Krakatau continued.
Ongoing eruptive activity persisted at Api Siau (Karangetang) with
explosions, lava flowage and avalanches. Avalanches continued at Merapi
too. Lokon-Empung experienced an ash eruption at 2230 on 18 August.
From: http://www.vsi.dpe.go.id/news/index.html
VOLCANIC ACTIVITY REPORTS
Weekly Report No. 626 13-26 August, 2001
Karangetang
Siau island; 2°47' N, 125°29' E; summit elevation 1784 m
Karangetang activity is continuing and seismic records showed dominant of
small explosion, avalanche and multiphase tipes. Smoke ejection from
northern main crater was in medium white-grey reached 100 m height. Visual
observation noted that height and color of the crater's smoke changed while
the booming sound was heard.
Effusive and avalanche activities ongoing during these two weeks. Lava flow
to the direction of Kehetang river as far as 1000 m, Keting river 1575 m,
from the edge of the flow avalanche often occurred as far as 1500 m.
Volcanic tremor recorded continuously which has maximum amplitude about
0.5-15 mm. Detail of seismic recorded during these period are deep volcanic
(VA) 4 events, shallow volcanic (VB) 7 events, tectonic 32 events,
multiphase 199 events, avalanche 447 events, small explosion earthquake 832
events, and continuous volcanic tremor.
Karangetang volcano is in level 3.
G. Kerinci
West Sumatera; 1°41.5' S, 101°16' E; summit elevation 3800 m
Seismic activity of Kerinci volcano during these two weeks dominated by
small explosion earthquakes. Eruption activity had been stopped. Visual
observation noted clear view of the mountain. White - brown smoke rose from
the crater reached maximum height about 500 above the summit. Lists of
seismic recorded during this period are deep volcanic (VA) 1 event, shallow
volcanic (VB) 6 events, small explosion earthquake 2252 events and tectonic
10 events.
Kerinci volcano is in level 2.
Merapi
Central Java; 7°32.5' S, 110°26.5' E; summit elevation 2911 m
Based on visual observation solfatara produced white thin-thick color
smoke, weak pressure with maximum height 275 m from Merapi's summit. Lava
avalanche continuing, observed about 379 times dominantly flowed to the
upper stream of Sat and Lamat rivers. Minor flow occurred to the direction
of Senowo and Bebeng rivers, with maximum sliding distance of 2.8 km.
Seismic activity dominated by avalanche earthquakes which relatively has
the same quality compare with two weeks before.
Merapi volcano is in level 2.
Lokon
North Sulawesi; 1°21.5' N, 124°47.5' E; summit elevation 1579.5 m
Plume from Tompaluan crater observed as white thin color reached height
about 25 - 270 m. On August 18, 2001, at 22.30 local time ash explosion
occurred. Ash reached 800 m height above crater rim and spread to Manado
(25 km northern of Lokon volcano). Observation of post-explosion seismicity
noted that there are significant increase on volcanic earthquake compare
with last data. Tremor volcanic recorded uncontinuously with maximum
amplitude of 0.5-1 mm. Seismic records during two weeks are deep volcanic
(VA) 57 events, shallow volcanic (VB) 261 events, tectonic 45 events and
uncontinuous tremor.
Lokon volcano is in level 2.
Ijen
East Java;8°3.5' S, 114°14.5' E; summit elevation 2386 m
Ijen crater produced white-grey smoke that rose about 50 m above the
summit. Tremor shocks recorded continuously with maximum amplitude of 0.5 -
3 mm. Seismograph noted that most of the earthquake record were tectonic,
volcanic and small explosion, which decrease compare to the week before
especially shallow volcanic. List of seismic record noted as: shallow
volcanic (VB) 42 events, continuous tremor, 1 event of small explosion and
6 events of tectonic.
Ijen volcano is in level 2.
Anak Krakatau
Sunda Straits, 6°6'5.8" S, 105°25'22.3" E; summit elevation 189,48 m
Seismic activity of Krakatau dominated with shallow volcanic and small
explosion earthquakes, with extreme raising on shallow volcanic. The other
earthquakes decrease compare to the week before. Visual appearance could
not be observed, because the volcano was covered by haze. Seismic and
infrasonic data during this week are 1 events of deep volcanic (VA),
shallow volcanic (VB) 189 events, explosion earthquake 49 events,
infrasonic 23, small explosion earthquake 275 events, and 1 event of
tectonic earthquake.
Anak Krakatau is stated in level 2.
Topic 2 of 99 [Geo]: Vulcanism
Response 594 of 997: Marcia (MarciaH) * Mon, Sep 10, 2001 (19:05) * 5 lines
Under the category of "the best-laid plans of mice and men..." this is what happens when you put a roadway where pele does not want it.
http://hvo.wr.usgs.gov/kilauea/update/main.html
Great images and a new map, too
Topic 2 of 99 [Geo]: Vulcanism
Response 595 of 997: Marcia (MarciaH) * Wed, Sep 12, 2001 (21:05) * 267 lines
GVP/USGS Weekly Volcanic Activity Report
5-11 September 2001
New Activity/Unrest: | Loihi Seamount, USA |
Ongoing Activity: | Etna, Italy | Kilauea, USA | Pinatubo, Philippines |
Popocatépetl, México | Shiveluch, Russia | Soufrière Hills, Montserrat |
Tungurahua, Ecuador |
New Activity
LOIHI SEAMOUNT Hawaii, USA 18.92°N, 155.27°W; summit elev. -980 m
On 10 September an earthquake swarm began at Loihi. The swarm began with a
M 5 earthquake and was followed by M 3.5-4.5 earthquakes until at least 11
September. This was the most severe swarm at Loihi since July 1996, when
the summit collapsed.
Background. Loihi seamount, the youngest volcano of the Hawaiian chain,
lies about 35 km off the SE coast of the island of Hawaii. Loihi (which is
the Hawaiian word for "long") has an elongated morphology dominated by two
curving rift zones extending north and south of the summit. The summit
region contains a caldera about 3 x 4 km wide and is dotted with numerous
lava cones, the highest of which is about 975 m below the sea surface.
Deep and shallow seismicity indicate a magmatic plumbing system distinct
from that of Kilauea volcano. Abundant fresh, sediment-free lavas and
low-temperature hydrothermal venting attest to the youthful age of the
volcano. During 1996, a new pit crater was formed at the summit of the
volcano, and lava flows were erupted. Continued volcanism is expected to
eventually build a new island at Loihi; time estimates for the summit to
reach the sea surface range from roughly 10,000 to 100,000 years.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Loihi Seamount Reports <
http://www.volcano.si.edu/gvp/volcano/region13/hawaii/loihi/var.htm> from
the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
No new eruptive activity has occurred at Etna since 10 August. During the
week strong degassing was observed at Bocca Nuova and Southeast craters.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Source: Charles Rivière’s web site
http://perso.club-internet.fr/rivierec/aout_2001.htm,
Italy’s Volcanoes http://www.geo.mtu.edu/~boris/ETNA_news.html
Etna Reports
from
the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava continued to flow down the Paluma pali scarp, across the coastal flat,
and into the ocean at the E Kupapa`u ocean entry. The lava flow that began
to cover a County lava-viewing road on 1 September ceased flowing by 5
September. Generally, volcanic tremor remained at low levels at Kilauea’s
summit and Pu`u `O`o. Tiltmeters across the volcano showed no significant
deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
PINATUBO Luzon, Philippines 15.13°N, 120.35°E; summit elev. 1,486 m
On 6 September workers began to partially drain Pinatubo’s rapidly rising
crater lake following the evacuation of ~40,000 NW-flank residents the
previous day. Initially water flowed slowly at ~50 m3 per hour through the
newly completed ~100-m-long spillway, but after workers increased the
gradient at the canal’s exit the flow rate increased to ~1,800 m3 per hour.
According to news reports, over several days the draining aimed to release
~25% of the water in the crater towards the NW down the Bucao River to the
South China Sea. Most residents were permitted to return to their homes on
7 September. According to reports on 10 September, the level of the crater
lake continued to rise following the draining. Therefore, further
preventative measures may be implemented.
Background. Prior to 1991 Pinatubo volcano was a relatively unknown,
heavily forested lava dome complex located 100 km NW of Manila with no
records of historical eruptions. The 1991 eruption, one of the world's
largest of the 20th century, ejected massive amounts of tephra and produced
voluminous pyroclastic flows, forming a small, 2.5-km-wide summit caldera
whose floor is now partially filled by a lake. Although the eruption caused
hundreds of fatalities and severe social and economic impact, successful
monitoring efforts greatly reduced the number of fatalities. Widespread
lahars that redistributed products of the 1991 eruption have continued to
cause severe disruption. At least six major eruptive periods, separated by
lengthy quiescence, have occurred from modern Pinatubo volcano during the
past 40,000 years. Most of these have produced major pyroclastic flows and
lahars that were even more extensive than in 1991.
Sources: Reuters 6/9
http://dailynews.yahoo.com/h/nm/20010906/wl/philippines_volcano_dc_4.html,
Associated Press 6/9
http://dailynews.yahoo.com/h/ap/20010906/wl/philippines_mount_pinatubo_7.htm
l,
CNN
http://www.cnn.com/2001/WORLD/asiapcf/southeast/09/05/phil.lake/index.html,
Reuters 7/9
http://dailynews.yahoo.com/h/nm/20010906/wl/philippines_volcano_dc_7.html
Associated Press 10/9
http://dailynews.yahoo.com/h/ap/20010910/wl/philippines_mount_pinatubo_14.html
Pinatubo Reports
from the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC 5 hours)
On 9 September at about 0815 an episode of frequent moderate-sized
eruptions began at Popocatépetl. The eruptions produced steam-and-ash
emissions that rose to a maximum height of 1 km above the crater and
drifted to the NW. During the night a small explosion sent incandescent
fragments up to 200 m from the crater. Eruptive activity continued through
at least 1230 on 9 September.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Sources: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
Seismic activity was above background levels during 31 August-7 September.
Spasmodic volcanic tremor and weak, shallow seismic signals (possible
collapses and avalanches) were registered the entire week. Several
gas-and-steam plumes were observed, with the highest rising 1.2 km above
the dome. On 4 September an explosion produced an ash plume that rose 1 km
above the dome and a 1-km-long pyroclastic flow that traveled to the SE.
Thermal anomalies were visible on satellite imagery. The volcano remained
at Concern Color Code Orange <
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm>.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
Activity at Soufrière Hills remained at similar levels as during the
previous week. Bands of tremor, associated with rockfalls and ash venting,
occurred at irregular intervals. The active lava dome appeared to be
growing rapidly and was well-formed, with steep sides and a rugged summit
area. Rockfalls and small pyroclastic flows that originated from the new
dome were observed in the upper reaches of the Tar River Valley. On the
night of 3 September incandescence was visible at the dome. According to
the Washington VAAC, rockfalls generated ash clouds that did not rise above
~1.5 km a.s.l.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Source: Montserrat Volcano Observatory http://www.mvo.ms/
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
Several small-to-moderate eruptions occurred at Tungurahua during the week.
The highest ash cloud reported was observed by a pilot and occurred on 8
September at 0828, rose ~10.5 km a.s.l., and drifted to the SW.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
from the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Topic 2 of 99 [Geo]: Vulcanism
Response 596 of 997: Marcia (MarciaH) * Tue, Sep 18, 2001 (00:12) * 11 lines
A new risk map that reveals the hazards associated with
Popocatépetl, Earth's riskiest volcano, has been developed
by geologists from the University at Buffalo (UB) in New York
and their colleagues at the National University of Mexico
(UNAM). Popocatépetl is located about 27 miles from Mexico
City.
more... http://www.popularmechanics.com/science/research/2001/9/paths_of_destruction/
Topic 2 of 99 [Geo]: Vulcanism
Response 597 of 997: Marcia (MarciaH) * Tue, Sep 18, 2001 (00:13) * 4 lines
the above map is (trying again to post same)
Topic 2 of 99 [Geo]: Vulcanism
Response 598 of 997: Marcia (MarciaH) * Tue, Sep 18, 2001 (15:52) * 21 lines
Finally, my email commeth in and goeth out from Hawaii OnLine.
Earthquake/Tsunami lecture at Te Papa Thursday 20th
This Thursday evening in Soundings Theatre at Te Papa (6.30pm) a group of GNS
scientists will give a public lecture to share their findings from a recent
reconnaissance trip to Peru to study the aftermath of a magnitude 8.4 earthquake
off the coast of southern Peru in June. As well as ground-shaking damage, the
quake also caused a tsunami that devastated coastal settlements.
The scientists will draw parallels with the North Island's east coast and
Wellington, where a similar type and size of offshore earthquake could occur,
also generating a tsunami. As well as examining the anatomy of this type of
earthquake, they will cover the engineering and planning implications of such an
event in New Zealand. The GNS team will be joined by Debbie Cunningham, an
emergency management specialist with the Wellington Regional Council. Debbie
will outline aspects of emergency response and community preparedness relating
to earthquakes and tsunamis.
Click here for more information:
http://www.tepapa.govt.nz/se_tsunami_web.html
Topic 2 of 99 [Geo]: Vulcanism
Response 599 of 997: Marcia (MarciaH) * Wed, Sep 19, 2001 (21:39) * 282 lines
GVP/USGS Weekly Volcanic Activity Report 12-18 September 2001
New Activity/Unrest: | Loihi Seamount, USA | Mount Hood, USA |
Ongoing Activity: | Etna, Italy | Karangetang, Indonesia | Kerinci,
Indonesia | Kilauea, USA | Krakatau, Indonesia | Popocatépetl, México |
Shiveluch, Russia | Soufrière Hills, Montserrat | Tungurahua, Ecuador |
New Activity
LOIHI SEAMOUNT Hawaii, USA 18.92°N, 155.27°W; summit elev. -980 m; All
times are local (=UTC - 10 hours)
An earthquake swarm occurred at Loihi during 10-11 September and two 13
September earthquakes may have also been part of the swarm. The two later
earthquakes occurred at 0311 and 0839 and had magnitudes of 4.9 and 4.4,
respectively. Most of the earthquakes from 10-13 September were ~12 km deep
and located slightly S of the summit of the volcano.
Background. Loihi seamount, the youngest volcano of the Hawaiian chain,
lies about 35 km off the SE coast of the island of Hawaii. Loihi (which is
the Hawaiian word for "long") has an elongated morphology dominated by two
curving rift zones extending north and south of the summit. The summit
region contains a caldera about 3 x 4 km wide and is dotted with numerous
lava cones, the highest of which is about 975 m below the sea surface.
Deep and shallow seismicity indicate a magmatic plumbing system distinct
from that of Kilauea volcano. Abundant fresh, sediment-free lavas and
low-temperature hydrothermal venting attest to the youthful age of the
volcano. During 1996, a new pit crater was formed at the summit of the
volcano, and lava flows were erupted. Continued volcanism is expected to
eventually build a new island at Loihi; time estimates for the summit to
reach the sea surface range from roughly 10,000 to 100,000 years.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Loihi Seamount Reports <
http://www.volcano.si.edu/gvp/volcano/region13/hawaii/loihi/var.htm> from
the monthly Bulletin of the Global Volcanism Network
HOOD Oregon, USA 45.374°N, 121.694°W; summit elev. 3,426
The USGS Cascades Volcano Observatory reported that a minor earthquake
swarm occurred at Mount Hood from 9 September until at least 14 September.
About 25 events were detected, with a maximum magnitude of 2.9. The
epicenters of the earthquakes were ~8 km SSW of the volcano’s summit at
depths of 1-7 km. These types of swarms occur once or twice per year at
Mount Hood.
Background. Mount Hood, Oregon's highest peak, forms a prominent backdrop
to the state's largest city, Portland. The eroded summit area consists of
several andesitic or dacitic lava domes; Pleistocene collapses produced
avalanches and lahars that traveled across the Columbia River to the north.
The glacially eroded volcano has had at least four major eruptive periods
during the past 15,000 years. The last three occurred within the past 1,800
years from vents high on the SW flank and produced deposits that were
distributed primarily to the south and west along the Sandy and Zigzag
rivers. The last eruptive period took place around 170-220 years ago, when
dacitic lava domes, pyroclastic flows and mudflows were produced without
major explosive eruptions. Minor 19th-century eruptions were witnessed from
Portland.
Source: US Geological Survey Cascades Volcano Observatory
http://vulcan.wr.usgs.gov/Volcanoes/Cascades/CurrentActivity/current_updates
.html
Hood Reports
http://www.volcano.si.edu/gvp/volcano/region12/oregon/hood/var.htm from the
monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
Volcanic activity resumed at Etna’s summit on 11 September. Loud explosions
emanated from the NW vent of Bocca Nuova crater at 5- to 10-minute
intervals. The explosions were followed by dense gas clouds, but no
volcanic fragments were ejected.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Source: Italy’s Volcanoes http://www.geo.mtu.edu/~boris/ETNA_news.html
Etna Reports
from
the monthly Bulletin of the Global Volcanism Network
KARANGETANG [Api Siau] Siau Island, Indonesia 2.47°N, 125.29°E; summit
elev. 1,784 m: All times are local (= UTC + 9 hours)
During 3-9 September lava flowed 0.5-1.8 km towards the Kahetang and Keting
rivers. Lava avalanches that originated from the edges of the flows
traveled up to 1 km. On 9 September at 0001 a pyroclastic flow traveled as
far as 750 m from the main crater to the Batang River (West Siau). During
the week seismicity was dominated by small explosion, avalanche, and
multiphase earthquakes. Discontinuous volcanic tremor was also detected.
The volcano remained at Alert Level 3 (on a scale of 1-4).
Background. Karangetang (also known as Api Siau) lies at the northern end
of the island of Siau, N of Sulawesi, and contains five summit craters
strung along a N-S line. One of Indonesia's most active volcanoes,
Karangetang has had more than 40 recorded eruptions since 1675.
Twentieth-century eruptions have included frequent explosions, sometimes
accompanied by pyroclastic flows and lahars.
Source: Volcanological Survey of Indonesia
Karangetang Reports
from the monthly Bulletin of the Global Volcanism Network
KERINCI Sumatra, Indonesia 1.69°S, 101.27°E; summit elev. 3,805 m; All
times are local (= UTC + 7 hours)
During 3-9 September activity at Kerinci was dominated by 1,128 small
explosion earthquakes. On 9 September during 0800-1200 small explosions
produced ash plumes that rose to 0.5 km above the volcano. Kerinci remained
at Alert Level 2 (on a scale of 1-4).
Background. The summit of 3,800-m-high Kerinci, Indonesia's highest
volcano, contains a deep 600-m-wide crater often partially filled by a
small crater lake. The massive 13 x 25 km wide volcano towers 2,400-3,300 m
above surrounding plains. Kerinci is elongated in a N-S direction and is
capped by an unvegetated young summit cone constructed NE of an older
crater remnant. One of Sumatra's most active volcanoes, Gunung Kerinci has
produced a series of moderate explosive eruptions during the 19th and 20th
centuries.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Kerinci Reports
from the Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava continued to flow down the Paluma pali scarp, across the coastal flat,
and into the ocean at the E Kupapa`u ocean entry. Generally, volcanic
tremor remained at low-to-moderate levels at Kilauea’s summit and Pu`u
`O`o. During 12 and 13 September very slight deflation occurred at
Kiliauea’s summit. During the rest of the week tiltmeters across the
volcano showed no significant deformation. On 17 September at Pu`u `O`o,
background tremor was interrupted at intervals of ten’s of minutes to an
hour or two, by short-lived bursts of relatively vigorous tremor.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
KRAKATAU Indonesia 6.10°S, 105.43°E; summit elev. 813 m
In comparison to the previous week there was a significant increase in
explosion and volcanic earthquakes at Krakatau during 3-9 September. The
number of small explosion earthquakes sharply decreased. The volcano
remained at Alert Level 2 (on a scale of 1-4).
Background. The renowned Krakatau volcano lies in the Sunda Strait between
Java and Sumatra. Collapse of the ancestral Krakatau edifice, perhaps in
416 AD, resulted in a 7-km-wide caldera. Remnants of this volcano formed
Verlaten and Lang Islands; subsequently Rakata, Danan and Perbuwatan
volcanoes were formed, coalescing to create the pre-1883 Krakatau Island.
Caldera collapse during the catastrophic 1883 eruption destroyed Danan and
Perbuwatan volcanoes, and left only a remnant of Rakata volcano. The
post-collapse cone of Anak Krakatau (Child of Krakatau), constructed within
the 1883 caldera at a point between the former cones of Danan and
Perbuwatan, has been the site of frequent eruptions since 1927.
Source: Volcanological Survey of Indonesia http://www.vsi.dpe.go.id/
Krakatau Reports
from
the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m
During the week, volcanic activity at Popocatépetl consisted of small
emissions of steam, gas, and minor amounts of ash.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html,
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
During 7-14 September several gas-and-ash plumes produced from explosions
at Shiveluch were observed, with the highest rising 1.2 km above the dome.
On 11 September several hot avalanches were observed travelling from the
top of the lava dome. On 12 September explosions produced a short
pyroclastic flow and an ash plume that rose to 1 km above the dome. During
the week, seismic activity was above background levels and spasmodic
volcanic tremor and weak, shallow seismic signals (possible collapses and
avalanches) were registered. Thermal anomalies were visible on satellite
imagery. The volcano remained at Concern Color Code Orange <
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm>.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
Activity at Soufrière Hills remained at levels similar to the previous
week. Bands of tremor, associated with rockfalls and ash venting, occurred
at irregular intervals. On 12 September continuous low-amplitude tremor
began and persisted until at least 14 September. The tremor accompanied
rockfalls. The active lava dome continued to produce rockfalls and small
pyroclastic flows that descended into the upper reaches of the Tar River
Valley. Ash clouds produced from rockfalls rose slightly above the summit
and were visible in satellite imagery.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Sources: Montserrat Volcano Observatory http://www.mvo.ms/
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m
During the week volcanic activity at Tungurahua was characterized by a
large number of long-period earthquakes, near-summit ash-and-gas emissions,
and sporadic small-to-moderate explosions. The highest ash cloud reached ~8
km a.s.l. On 11 September, and to a lesser extent on 12 September, ash fell
to the N of the volcano in the towns of Pondoa, Runtun, and Baños. In
addition, ash fell to the SW in Quero and Penipe, and mud flows were
reported in Penipe. Explosions on 13 September deposited ash to the W of
the volcano, affecting the towns of Juive, Cotalo, and Bibao. On the 15th
ash fell to the SW in Riobamba and Penipe. On 16 September incandescent
material was emitted from the volcano along with ash and gas. The Alert
Level remained at Yellow in the town of Baños and at Orange for the rest of
the population in the high-risk zone, as it has since 5 September 2000.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
from the monthly Bulletin of the Global Volcanism Network
********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Topic 2 of 99 [Geo]: Vulcanism
Response 600 of 997: Marcia (MarciaH) * Fri, Sep 21, 2001 (16:01) * 86 lines
Kilauea Volcano Watch - September 20, 2001
How our capabilities have improved with time
Forty years ago, at 12:36 p.m. on September 21, a swarm of large,
shallow earthquakes accompanied by strong harmonic tremor began to emanate
from the vicinity of Napau Crater on the east rift zone of Kilauea Volcano.
A rapid deflation of the summit of Kilauea occurred in conjunction with the
earthquake swarm.
These events were precursors to an eruption and were caused by magma
draining from the summit storage system and forcefully intruding the rift
zone. Personnel at the Hawaiian Volcano Observatory were uncertain about
the location of the possible eruption because of the scant monitoring
network in place at that time.
HVO directly recorded the signal from only four seismic stations on
Kilauea. Three more stations, one each in Pahoa, Hilo, and Kealakekua,
were recorded on site, and their records had to be transported to HVO. One
tiltmeter that had to be manually read was the only daily source of
information about surface deformation.
The first observation of a possible eruption was a glow over the east
rift zone forest at 4:30 a.m. on September 22. At 8:00 a.m., a tourist
flight confirmed a breakout near Kalalua Crater. With no immediate access
to a helicopter or airplane, HVO personnel had to wait until noon before
they were able to take an overflight of the eruption area with the Hawai`i
National Guard.
The observers found a series of discontinuous fissures stretching 15
km (9 mi) from Napau Crater downrift to Kalalua Crater (the initial phase
of the current Pu`u `O`o eruption had nearly an identical breakout). Only
copious steam and volcanic fumes were being emitted from the cracks by the
time HVO personnel flew over the area. Fresh lava pads surrounded three of
the fissures, but no fountaining was observed.
The island was rocked at 5:02 p.m. on September 22 by a large
earthquake from the south flank of Kilauea. The earthquake apparently
allowed the eruptive dike to move farther down the rift zone. At about
10:00 a.m. on September 23, a new 4-km-long (2.5-mi-long) fissure broke out
about 8.3 km (5 mi) east of the previous day's activity.
The discontinuous curtain of fountains lasted only a few minutes and
consolidated to a 200-m-long (700-ft-long) vent located northwest of
Heiheiahulu Crater. Activity at this vent produced flows that threatened
the Kalapana road, and the Hawai`i County Civil Defense Agency ordered the
evacuation of homes from `Opihikao to Kapa`ahu. Most of the lava, however,
poured down large cracks, and no extensive flow resulted. This eruptive
phase lasted 15 hours and produced three distinctive flow fields. The
easternmost flow field, Jonika, was named for the rancher who allowed HVO
personnel to pass through his property and guided us to the eruption site.
Eruptive activity resumed at 2:15 p.m. on September 24 from a
150-m-long (500-ft-long) fissure located between Kalalua and Heiheiahulu
craters. The fountains were low-level and ended by early the next morning.
Two small elongated cones resulted from this activity.
During the evening of September 24, a swarm of earthquakes from the
south flank shook the area. Three earthquakes were felt throughout the
island, with the largest, at 7:30 p.m., having a magnitude of 5.5. This
earthquake nearly caused a newly arrived HVO staff member to go back to
O`ahu, but he stayed on and worked in seismology for another 28 years
before retiring from HVO.
The 1961 flank eruption ushered in 40 years of great activity along
Kilauea's middle and upper east rift zone. Since then, HVO has gradually
increased our real-time monitoring capabilities to cope with all this
activity and that of Mauna Loa. Now the seismic network consists of more
than 60 stations on this island and three on Maui, and all of their signals
are telemetered and recorded at HVO. A dozen electronic tilt stations,
four borehole strainmeters, and nearly two dozen GPS receivers send their
signals to HVO. We also have ready access to a number of helicopters.
When the first eruptive fissure of the current eruption broke the surface
near Napau Crater on January 3, 1983, HVO personnel were standing only a
few meters (yards) away.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week. Lava moves away from the vent toward the
ocean in a network of tubes and descends Pulama pali in three separate
tubes. Two surface flows from breakouts of the tube system continue to
stream down the pali, and many surface flows are active in the coastal
flats. Lava enters the ocean in the area east of Kupapa`u and provides
visitors to the viewing area a great show.
The public is reminded that the bench of the ocean entry is very
hazardous, with possible collapses of the new land. The steam cloud is
extremely hot, highly acidic, and laced with glass particles. Swimming at
the black sand beach of the bench can be a blistering or even deadly
venture.
There were no earthquakes reported felt during the week ending on
September 20. The swarm of earthquakes from Lo`ihi Volcano has subsided.
HVO located a total of 57 earthquakes from Lo`ihi since September 10.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
Topic 2 of 99 [Geo]: Vulcanism
Response 601 of 997: Marcia (MarciaH) * Fri, Sep 21, 2001 (17:19) * 14 lines
Undersea Volcano Erupts Near Iwojima Island
TOKYO (Reuters) - Japan's Meteorological Agency said on Friday a small
underwater volcanic eruption took place near the island of Iwojima, 800 miles south of Tokyo, where U.S. military have been holding exercises.
"I would describe it as a small-scale volcanic activity," said Keiji Doi, a senior scientific officer for the agency, adding that there were no reports of damage on the island.
"Based on patterns of activity on Iwojima in the past, we are very optimistic about the outlook and think the situation will calm down after today's activity," said Doi.
He added however, that predictions of future activity were always difficult.
At one point, the volcanic activity caused sea water to shoot up several tens of yards from sea level and white smoke to rise up to 984 feet in the air, said agency officials.
The latest reports said sea water was shooting up about 3 feet with white smoke
rising several meters in an area about 200 meters from the southern tip of the island.
More... http://reuters.com/news_article.jhtml?type=sciencenews&StoryID=236768#
Topic 2 of 99 [Geo]: Vulcanism
Response 602 of 997: Marcia (MarciaH) * Mon, Sep 24, 2001 (20:59) * 53 lines
*********************************************************
Montserrat Volcano Observatory: Weekly Activity Report
*********************************************************
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 14 September 2001 to midday, 21 September
2001
Activity at the Soufrière Hills Volcano has shown a moderate increase
compared with that of the previous week. In particular, there has been a
marked increase in hybrid earthquake events. The seismograph network
recorded 211 rockfall signals, 36 long period events, 4 long period
rockfalls, 522 hybrid events and 3 volcanotectonic earthquakes.
Activity recorded by the seismic monitoring network over the past week
has been dominated by banded tremor. On average, the bands of tremor
have occurred every 13 hours and have been slightly more intense when
compared with those of the previous week. In addition, the number and
strength of hybrid events associated with these tremor episodes have
increased; which is a pattern consistent with the moderate rate of
dome-growth and periods of vigorous degassing.
The active lava dome was seen on most days and is growing at a moderate
rate, producing rockfalls and small pyroclastic flows in the upper
reaches of the Tar River Valley. Periods of vigorous ash-venting and
increased rockfall activity have occurred during periods of tremor. The
volume of the new dome is estimated to be approximately 12 million cubic
metres, which is equivalent to an average growth rate of approximately
2.6 cubic metres per second since the collapse on 29th July.
Sulphur dioxide emission rates were measured on most days, both during
and between periods of banded tremor. These emissions ranged from 2.5 to
25 kilograms per second, which is approximately equivalent to fluxes of
between 200 and 2000 tonnes per day respectively. This wide variation in
measurements reflects pulses of gas-release on the scale of hours; with
maximum fluxes occurring during periods of banded tremor. Open-path
FTIR measurements indicate HCl:SO2 mass ratios of between 2 and 3
during the reporting period, which is consistent with the dome growing
at a moderate rate.
The daytime entry zone (DTEZ) remains open. Activity could increase
quite suddenly, with a dangerous situation developing very quickly. Ash
masks should be worn in ashy conditions. The Belham Valley should be
avoided during and after heavy rainfall due to the possibility of
mudflow activity.
Residents of Montserrat and visitors to the island are advised to tune
into ZJB Radio for up-to-date information on the volcano. Access to
Plymouth, Bramble airport and beyond is prohibited. There is a maritime
exclusion zone around the southern part of the island that extends two
miles beyond the coastline from Trant's Bay in the east to Garibaldi
Hill on the west coast.
12 noon, Friday, 21 September 2001
Peter Dunkley
Montserrat Volcano Observatory
Mongo Hill
Montserrat
West Indies
Topic 2 of 99 [Geo]: Vulcanism
Response 603 of 997: Marcia (MarciaH) * Mon, Sep 24, 2001 (21:04) * 242 lines
************************************
KVERT Information Release 57-01,
September 21, 2001
************************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 57-01
Friday, September 21, 2001, 14:35 KDT (01:35 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity was above background levels this past week. Four MI>=2
and twenty-two MI>=1.7 earthquakes were registered. Several types of
seismic activity were registered at the volcano during the entire week,
consisting of: many weak shallow earthquakes within the volcano's edifice;
many series (on September 13-15 and 19) and many long series (on September
16-18) of weak local shallow seismic signals (possibly short-lived
explosions); local shallow seismic events (possible collapses, avalanches)
and an intermittent spasmodic tremor. The volcanic tremor amplitudes were,
on average, 0.5x 10-6 mps on September 13; 0.4x 10-6 mps on September 14
and 0.55x 10-6 mps on September 15. On September 16 the volcanic tremor
amplitude increased, on average, to 0.8x 10-6 mps and it decreased
gradually from 0.3x 10-6 to 0.22x 10-6 mps on September 17-19.
Observers in Klyuchi town reported that explosions sent an ash plume 1,100
m above the dome (3,550 m; 11,700 ft. ASL) at 13:12 KDT (00:12 UTC) on
September 14. The ash plume extended to the east. On September 17, a gas
and steam plume rose 400 m above the dome (2,850 m; 9,400 ft. ASL) and
extended 20 km to the southeast. At 10:00 KDT on September 18 (21:00 UTC
on September 17) and at 16:10 KDT (03:10 UTC) on September 18, gas and
steam plumes rose 800 and 1,200 m above the dome (3,250 and 3,650 m; 10,700
and 12,050 ft. ASL). Hot avalanches from the summit of the dome were
observed. A gas and steam plume rose 400 m above the dome (2,850 m; 9,400
ft. ASL) on September 20. At other times, clouds obscured the volcano.
A satellite image, at 08:00 KDT on September 18 (19:00 UTC on September
17), showed a 4-pixel thermal anomaly (2 pixels near saturation at 44 to 49
degrees C in a region with a background of ?10 to 1-5 degrees C) located
in the active dome area. Satellite images showed a 3-pixel thermal anomaly
at the volcano at 07:38 KDT on September 19 (18:38 UTC on September 18)
including 2 pixels at sensor saturation (~49 degrees C), within a
background near ?5 degrees C. A possible steam plume, approximately 25 km
long, bearing 135 degrees, was observed rising from the volcano in a
satellite image at 17:27 KDT (04:27 UTC) on September 19. A >5-pixel
thermal anomaly at the volcano was seen in a satellite image at 07:27 KDT
on September 20 (18:13 UTC on September 19), including 2 pixels near
saturation, in a background of ?12 degrees C.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was above background levels this past week. One MI>=2 and
one MI>=1.7 earthquakes were registered on September 13. According to
visual data from Klyuchi town, on September 14, the volcano was quiet. On
September 13,17,and 19-20, gas and steam plumes rose 50-150 m above the
crater (4,800-4,900 m, 15,800-16,200 ft. ASL). On September 18, a gas and
steam plume rose 1,000 m above the crater (5,750 m, 19,000 ft. ASL), and
extended 20 km to the south. At other times, clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels on September 16. At other times,
no seismicity was registered under the volcano. Observers in Kozirevsk
village reported that a gas and steam plume rose 100 m above the dome
(3,000 m, 9,900 ft. ASL). On September 14 the volcano was quiet.
Observations of weak fumarolic activity at the volcano were recorded on
September 15,18 and 20. At other times, clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity at Avachinsky volcano was at background levels the entire
week. No seismicity was registered under Koryaksky volcano on September 19
but seismicity at the volcano was at background levels at all other times.
On September 19, a gas and steam plume rose 30 m above the crater at
Avachinsky volcano (2,780 m, 9,200 ft. ASL). The volcanoes were quiet on
September 14, 16-17, and 20. At other times, clouds obscured the
volcanoes.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
No Seismicity was registered under Gorely volcano on September 17. At
other times, seismicity at the volcano was at background levels. No
seismicity was registered under Mutnovsky volcano this past week. AT 11:00
KDT on September 19 (22:00 UTC on September 18) a gas and steam plume rose
200 m above the crater of Mutnovsky volcano (2,500 m, 8250 ft. ASL). The
volcanoes were quiet on September 14, 19-20. At other times, clouds
obscured the volcanoes.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006
RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
907-786-7497
************************************
KVERT Information Release 56-01,
September 14, 2001
************************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 56-01
Friday, September 014, 2001, 14:55 KDT (01:55 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Seismic activity was above background levels this past week. Many weak
shallow earthquakes within the volcano's edifice and many series of weak
local shallow seismic signals (possible short-lived explosions) were
registered the entire week. An intermittent spasmodic volcanic tremor was
recorded the entire week. The tremor amplitudes were, on average, 0.3x 10
(superscript: -6) mps on September 6 and 9-10; 0.4x 10(superscript: -6) mps
on September 7-8 and 0.5x 10(superscript: -6) mps on September 11-12. At
20:26 KDT (07:26 UTC) on September 07 possible short-lived explosions,
accompanied by a series of shallow events, about 3 -minutes-long each, were
registered. Local shallow seismic events (possible collapses, avalanches)
were recorded on September 10-12. From 16:30 until 17:50 KDT (from 03:30
until 04:50 UTC) on September 10 and a number of local shallow events
(A/Tmax= 11.3x 10(superscript: -6 )mps) and the spasmodic volcanic tremor
up to 0.8x 10(superscript: -6) mps were registered. This seismic data
indicated a possible ash explosion 6,000 m above the dome (8,450 m, 27,900
ft. ASL).
Observers in Klyuchi town reported that a gas and steam plume rose 300 m
above the dome (2,750 m; 9,100 ft. ASL) at 08:10 and 17:30 KDT (19:10 UTC
on September 06 and at 04:30 UTC) on September 07. At 20:32 KDT (07:32 UTC)
on September 07 an ash plume rose 1,200 m above the dome. At 08:00 KDT on
September 8 (19:00 UTC on September 7) and at 18:45 KDT (05:45 UTC) on
September 8 gas and steam plumes rose 800 and 400 m above the dome (3,250
and 2,850 m; 10,700 and 9,400 ft. ASL). At 08:20 KDT on September 09 (19:20
UTC on September 08) and at 08:00 KDT on September 10 (19:00 UTC on
September 09) gas and steam plumes rose 100 m above the dome (2,550 m,
8,400 ft. ASL). From 17:00 until 17:30 KDT (from 04:00 until 04:30 UTC) on
September 11 several hot avalanches from the summit of the dome were
observed. Gas-ash plumes of the avalanches rose 400 m and extended 5 km to
the east. At 09:05 KDT on September 12 (20:05 UTC on September 11) a gas
and steam plume rose 100 m above the dome and extended 10 km to the east.
According to visual data from Klyuchi town, at 12:37 KDT on September 12
(23:37 UTC on September 11) explosions sent an ash plume 1,000 m above the
dome (3,450 m; 11,400 ft. ASL) and short pyroclastic flow. At 17:20 KDT
(04:20 UTC) on September 12 a gas and steam plume rose 200 m above the dome
(2,650 m, 8,750 ft. ASL). At 15:30 KDT (02:30 UTC) on September 13 a gas
and steam plume rose 1,000 m (3,450 m; 11,400 ft. ASL) and extended 5 km to
the east. According to visual data from Klyuchi town, at 13:12 KDT (00:12
UTC) on September 14 an ash plume rose 1,100 m above the dome (3,550 m,
11,700 ft. ASL) and extended to the east. At other times, clouds obscured
the volcano.
A satellite image, at 18:02 KDT (05:02 UTC) on September 7, showed a
2-pixel thermal anomaly (39 degrees C in a background of 3 degrees C) at
the active dome area. Satellite images showed a 3-pixel thermal anomaly at
the volcano at 07:46 KDT on September 10 (18:46 UTC on September 09 (at 4
to 34 degrees C in a background of -10 degrees C). Possible a gas-steam-ash
(?) plume ~40-km-long extending to the north-northeast from the volcano was
seen in an image at 07:15 KDT on September 11 (18:15 UTC on September 10).
Satellite images showed a 6-pixel thermal anomaly at the volcano at 07:01
KDT on September 12 (18:01 UTC on September 11 (48.57 degrees C for two
saturated pixels, in a background -7 degrees C). A 3-pixel thermal anomaly
was seen in an image at 18:07 KDT (05:07 UTC) on September 13 (at 35 to 41
degrees C in a background of 10 to 20 degrees C).
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m. CURRENT LEVEL
OF CONCERN COLOR CODE IS GREEN. Seismic activity was a little above
background levels on September 9 but seismicity at the volcano was at
background levels at all other times. According to Kozirevsk seismic
stations data, from 03:36 until 03:46 KDT on September 09 (from 14:36 until
14:46 UTC on September 08) a series of shallow earthquakes was registered.
A weak fumarolic activity of the volcano was recorded on September 7. On
September 09 gas and steam plumes rose 100-200 m above the crater
(4,850-4,950 m, 16,000-16,300 ft. ASL); on September 11 - 50 m above the
crater (4,800 m, 15,800 ft. ASL); on September 13 - 100 m above the crater
(4,850 m, 16,000 ft. ASL). At other times, clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m. CURRENT LEVEL
OF CONCERN COLOR CODE IS GREEN. Seismic activity was at background levels
on September 9-11. At other times, no seismicity was registered under the
volcano. Observers in Kozirevsk village reported that a weak fumarolic
activity of the volcano was recorded on September 9 and 11. On September 12
a gas and steam plume rose 50 m above the dome (2,950 m, 9,700 ft. ASL) and
extended 5 km to the southeast. On September 6 and 10 the volcano was
quiet. At other times, clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m. CURRENT LEVEL OF
CONCERN COLOR CODE IS GREEN. Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m. CURRENT LEVEL OF
CONCERN COLOR CODE IS GREEN. Seismic activity at Avachinsky volcano was at
background levels the entire week. No seismicity was registered under
Koryaksky volcano on September 7 (no data was on September 6) but
seismicity at the volcano was at background levels at all other times. The
volcanoes were quiet on September 7, 9-13. At 11:00 KDT on September 10
(22:00 UTC on September 09) a weak fumarolic activity was observed at
Avachinsky volcano. At other times, clouds obscured the volcanoes.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m.
CURRENT LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN. Seismicity
at Gorely volcano was at background levels on September 7, 10-11. At other
times, no seismicity was registered under the volcano. No seismicity was
registered under Mutnovsky volcano this past week. The volcanoes were quiet
on September 7, 9, 11-13. At other times, clouds obscured the volcanoes.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006
RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508
USA
E-mail: tlmurray@usgs.gov
907-786-7497
Topic 2 of 99 [Geo]: Vulcanism
Response 604 of 997: Marcia (MarciaH) * Fri, Sep 28, 2001 (17:39) * 277 lines
GVP/USGS Weekly Volcanic Activity Report 19-25 September 2001
New Activity/Unrest: | Iwo-jima, Japan |
Ongoing Activity: | Karangetang, Indonesia | Kerinci, Indonesia | Kilauea,
USA | Krakatau, Indonesia | Merapi, Indonesia | Popocatépetl, México |
Shiveluch, Russia | Soufrière Hills, Montserrat | Tungurahua, Ecuador |
New Activity
IWO-JIMA Volcano Islands, Japan 24.75°N, 141.33°E; summit elev. 161 m; All
times are local = (UTC + 9 hours)
At 1015 on 21 September a submarine eruption began off of the SE coast of
Iwo-jima, an island inhabited by U.S. and Japanese military personnel
approximately 1,300 km S of Tokyo. The eruption was preceded by isolated
and continuous tremor beginning on the evening of 20 September. Visible
evidence of the eruption consisted of seawater gushing several meters above
sea level near the island’s coast and an area of discolored seawater
extending 300-400 m in length. During 1000-1100 approximately 30
earthquakes occurred in the active area; the typical rate is one or two
earthquakes per hour. The climax of the eruption occurred during 1200-1500.
At about 1300 water gushed several ten’s of meters above sea level and
steam rose to 100-300 m above the sea. JMA personnel observed seawater
rising intermittently during 1515-1715 at two points 50 m apart and 150-200
m from the island’s SE coast. The temperatures at these points were 33-34
ºC and 50 ºC, while the surrounding water was at 27 ºC. By 1500 ten
earthquakes were recorded per hour. During 1600-1700 three eruption sites
were visible; at one a pyroclastic cone was slightly above the sea surface.
JMA reported that by the next day volcanic and seismic activity returned to
usual levels, with zero to four earthquakes occurring per hour and no
tremor events.
Background. Iwo-jima in the central Volcano Islands portion of the
Izu-Marianas arc lies within a 9-km-wide submarine caldera. The triangular,
8-km-long island narrows toward its SW tip. Iwo-jima (whose name means
"Sulfur Island") has undergone dramatic uplift for at least the past 700
years accompanying resurgent doming of the caldera. A shoreline landed upon
by Captain Cook's surveying crew in 1779 is now 40 m above sea level. The
roughly 160-m-high Moto-yama plateau on the NE half of the island consists
of submarine tuffs overlain by coral deposits and forms the island's high
point. Many NE-SW-trending fumaroles are located on Iwo-jima (also spelled
Io-jima), and temperature gradients are high. Numerous historical phreatic
eruptions, many from vents on the W and NW sides of the island, have
accompanied the remarkable uplift of Iwo-jima.
Sources: Volcano Research Center
http://hakone.eri.u-tokyo.ac.jp/vrc/erup/iojima.html,
Japanese Meteorological Agency http://www.kishou.go.jp/english/index.html,
Reuters
http://dailynews.yahoo.com/h/nm/20010921/sc/japan_iwojima_volcano_dc_1.html
Iwo-jima Reports
from
the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
KARANGETANG [Api Siau] Siau Island, Indonesia 2.47°N, 125.29°E; summit
elev. 1,784 m
During 10-16 September fewer lava flows and lava avalanches traveled down
the flanks of Karangetang than in the previous week. Lava flowed down the
Kahetang and Keting rivers as far as 1.5 km, and one-km-long avalanches
developed at the ends of these flows. Seismicity was dominated by small
explosion and multiphase earthquakes. Emissions of steam and possibly ash
at the northern main crater rose to 0.5 km. The volcano remained at Alert
Level 3 (on a scale of 1-4).
Background. Karangetang (also known as Api Siau) lies at the northern end
of the island of Siau, N of Sulawesi, and contains five summit craters
strung along a N-S line. One of Indonesia's most active volcanoes,
Karangetang has had more than 40 recorded eruptions since 1675.
Twentieth-century eruptions have included frequent explosions, sometimes
accompanied by pyroclastic flows and lahars.
Source: Volcanological Survey of Indonesia
Karangetang Reports
from the monthly Bulletin of the Global Volcanism Network
KERINCI Sumatra, Indonesia 1.69°S, 101.27°E; summit elev. 3,805 m
The number of small explosion earthquakes at Kerinci increased to 2,281
during 10-16 September from 1,128 the previous week. Steam plumes rose to
600 m above the volcano, which remained at Alert Level 2 (on a scale of 1-4).
Background. The summit of 3,800-m-high Kerinci, Indonesia's highest
volcano, contains a deep 600-m-wide crater often partially filled by a
small crater lake. The massive 13 x 25 km wide volcano towers 2,400-3,300 m
above surrounding plains. Kerinci is elongated in a N-S direction and is
capped by an unvegetated young summit cone constructed NE of an older
crater remnant. One of Sumatra's most active volcanoes, Gunung Kerinci has
produced a series of moderate explosive eruptions during the 19th and 20th
centuries.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Kerinci Reports
from the Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava continued to enter the ocean at the E Kupapa`u ocean entry. Lava
flowed down the Pulama pali scarp W and E of the active flow field. The
western flow was mainly `a`a. The more vigorous eastern flow had been
active for more than two weeks. Surface lava flowed within about 0.6 km of
the coastline about 1.8 km W of the E Kupapa`u ocean entry. Generally,
volcanic tremor remained at moderate-to-low levels at Kilauea’s summit and
Pu`u `O`o. Background tremor at Pu`u `O`o was interrupted at intervals of
ten's of minutes to an hour or two, by short-lived bursts of relatively
vigorous tremor. Tiltmeters across the volcano showed no significant
deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
KRAKATAU Indonesia 6.10°S, 105.43°E; summit elev. 813 m
The number of explosion earthquakes decreased significantly during 10-16
September in comparison to the previous week, while the number of small
explosion earthquakes increased. The volcano remained at Alert Level 2.
Background. The renowned Krakatau volcano lies in the Sunda Strait between
Java and Sumatra. Collapse of the ancestral Krakatau edifice, perhaps in
416 AD, resulted in a 7-km-wide caldera. Remnants of this volcano formed
Verlaten and Lang Islands; subsequently Rakata, Danan, and Perbuwatan
volcanoes were formed, coalescing to create the pre-1883 Krakatau Island.
Caldera collapse during the catastrophic 1883 eruption destroyed Danan and
Perbuwatan volcanoes, and left only a remnant of Rakata volcano. The
post-collapse cone of Anak Krakatau (Child of Krakatau), constructed within
the 1883 caldera at a point between the former cones of Danan and
Perbuwatan, has been the site of frequent eruptions since 1927.
Source: Volcanological Survey of Indonesia http://www.vsi.dpe.go.id/
Krakatau Reports
from
the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
According to VSI, during 10-16 September volcanic activity at Merapi
decreased in comparison to the previous week. Incandescent lava avalanches
continued to travel SW as far as 2.5 km to reach the upstream portions of
the Lamat and Senowo rivers. Seismographs recorded 588 lava-avalanche
events during the report period. The volcano remained at Alert Level 2 (on
a scale of 1-4).
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Merapi Reports
from
the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m
During the week, volcanic activity at Popocatépetl consisted of small
emissions of steam, gas, and minor amounts of ash, and episodes of harmonic
tremor. Analysis of aerial photographs taken on 20 September revealed that
the lava dome had continued to grow since it was first observed on 10
August. The dome is growing inside the inner crater, which formed within
the summit crater after a dome was destroyed in December 2000.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html,
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
During 14-21 September several steam-and-gas clouds were observed, as were
ash clouds produced from explosions at Shiveluch, with the highest ash
cloud rising 1.1 km above the lava dome. During the week hot avalanches
from the summit of the dome were also noted. Seismic activity was above
background levels and spasmodic volcanic tremor and weak, shallow seismic
signals (possible collapses and avalanches) were registered. Thermal
anomalies in the active dome area were visible on satellite imagery.
Shiveluch remained at Color Concern Code Orange <
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm>.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
There was a moderate increase in volcanic activity at Soufrière Hills in
comparison to the previous week. A marked increase in hybrid earthquake
events was recorded and banded tremor events were slightly more intense. In
addition, the number and strength of hybrid events associated with the
banded tremor increased. The active lava dome continued to grow at a
moderate rate, producing rockfalls and small pyroclastic flows that
traveled E to the upper reaches of the Tar River Valley. The dome’s volume
was estimated to be 12 million cubic meters, therefore, the average growth
rate has been ~2.6 cubic meters per second since the partial dome collapse
on 29 July. Episodes of vigorous ash venting and increased rockfall
activity occurred during periods of tremor. Low-level ash plumes from this
activity were visible in satellite imagery.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Sources: Montserrat Volcano Observatory http://www.mvo.ms/
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
During the week several moderate-sized explosions and low-level emissions
of ash and gas occurred. An explosion on 20 September at 1044 produced an
ash cloud that rose to 2 km above the volcano and drifted to the WSW. The
explosion was accompanied by loud roaring and the sound of rockfalls. Small
amounts of ash fell in Pillate, Juive, and Runtún. The explosion was
preceded by tremor for approximately 3 hours. On 21 September at 1625
another moderate-sized explosion produced an ash cloud that rose to 3 km
above the volcano’s summit and drifted to the NW. During the night
incandescence was visible at the volcano’s crater.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
from the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Topic 2 of 99 [Geo]: Vulcanism
Response 605 of 997: Marcia (MarciaH) * Tue, Oct 2, 2001 (18:44) * 40 lines
******************************
Volcanic activity in Tonga?
******************************
From: HYVERNAUD Olivier
On September 2001, 27, 28 and 30, numerous short T waves have been
received by the French Polynesian Seismic Network. A preliminary
location gives a well constrained latitude at 18.18S, and a less
constrained longitude at 174W, in Tonga archipelago. This hydro acoustic
activity is interpreted as volcanic explosive activity, and can not be
related to seismic activity of the Tonga trench. The hydro acoustic
source could be near Fonualei volcano.
Additional informations will be send in few weeks.
Olivier HYVERNAUD
Laboratoire de Géophysique
POBOX 640 Papeete
TAHITI
FRENCH POLYNESIA
fax: 689 83 50 37
email : hyvernaud@labogeo.pf
******************************
new volcano book
******************************
From: D.A.Rothery@open.ac.uk
'Volcanoes' by David A. Rothery (266pp) is published on 28th September, by
Hodder & Stoughton as part of their 'Teach Yourself' series. UK price is GPB
8.99 ISBN 0-340-79047-4
(US publisher McGraw-Hill, $12.95, ISBN 0-07-138446-4)
It is intended as an introductory text on volcanoes and does not assume a
lot of prior geological knowledge. Chapters are: 'Introduction', 'What
causes volcanoes?', 'Eruptions', 'Types of volcano', 'Volcanic hazards',
'Volcanoes & climate', 'Monitoring volcanoes', 'Living with volcanoes',
'Visiting volcanoes', and 'Extraterrestrial volcanoes'.
Topic 2 of 99 [Geo]: Vulcanism
Response 606 of 997: Marcia (MarciaH) * Wed, Oct 3, 2001 (20:54) * 436 lines
GVP/USGS Weekly Volcanic Activity Report
26 September- 2 October 2001
New Activity/Unrest: | Shiveluch, Russia | Talang, Indonesia |
Ongoing Activity: | Etna, Italy | Karangetang, Indonesia | Kavachi, Solomon
Islands | Kilauea, USA | Manam, Papua New Guinea | Merapi, Indonesia |
Popocatépetl, México | Rabaul, Papua New Guinea | Semeru, Indonesia |
Soufrière Hills, Montserrat | Tungurahua, Ecuador | Ulawun, Papua New Guinea
New Activity
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m; All times are local (= UTC + 12 hours)
During 28-29 September seismic activity was above background levels and
weak, shallow seismic signals (possible collapses and avalanches) were
registered. Several small explosions occurred on 30 September, sending ash
clouds to the following heights above the dome: 2.5 km at 1323, 3.5 km at
1719, 2.5 km at 1755, and 4.5 km at 1807. An explosion at 2010 produced an
umbrella-shaped ash cloud that rose 9 km above the lava dome and extended
~9 km E to W. Large pyroclastic flows traveled ~5 km to the SE. The same
day the Concern Color Code was raised from Orange to Red
. During 28-30
September thermal anomalies in the active dome area were visible on
satellite imagery. Following the eruption, during 30 September at 2100 to 1
October at 0900, seismic activity decreased and the view of the volcano was
obscured by clouds. AVHRR satellite imagery at 0757 showed that the
~25-km-diameter ash cloud remained centered over the volcano. On 1 October
the Concern Color Code was reduced back to Orange.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Sources: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm,
Anchorage VAAC http://www.ssd.noaa.gov/VAAC/OTH/AK/messages.html,
Tokyo VAAC http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html,
China Daily.com http://www1.chinadaily.com.cn/news/wn/2001-10-02/36628.html
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
TALANG Sumatra, Indonesia 00.98°S, 100.68°E; summit elev. 2,896 m; All
times are local (= UTC + 7 hours)
During 24-30 September volcanic activity increased at Talang volcano.
Observers noted that on 25 September during 1722-1838 a thick
white-brownish plume with high gas pressure rose 200-350 m above the
volcano. Personnel at the observatory could smell sulfur during the
evening. In comparison to measurements in 2000, temperatures increased in
2001 at Batu Bajanjang hot spring (from 40-60°C to 45-66°C), Gabuo Atas
fumarole field (from 98-99°C to 111-114°C), and Gabuo Bawah fumarole field
(from 96-99°C to 100-101°C). In addition, the water level at Batu Bajanjang
hot spring decreased drastically. Talang was at Alert Level 2 (on a scale
of 1-4).
Background. Talang, which forms a twin volcano with the extinct Pasar Arbaa
volcano, has two crater lakes on its flanks. The largest of these is 1 x 2
km wide Danau Talang. No historical eruptions have occurred from the summit
of the volcano, which lacks a crater. All historical eruptions from Gunung
Talang volcano have involved small-to-moderate 19th-century explosive
activity originating from a series of small craters in a valley on the
upper NE flank.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Talang Reports <
http://www.volcano.si.edu/gvp/volcano/region06/sumatra/talang/var.htm> from
the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
According to reports on 28 September, gas emissions from Bocca Nuova crater
had been vigorous at times during the previous few weeks. In addition, a
dense gas plume was visible rising above Northeast Crater. The cones that
formed during the July-August 2001 eruption on the S flank continued to
emit heat and minor amounts of gas.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Source: Italy’s Volcanoes http://www.geo.mtu.edu/~boris/ETNA_news.html
Etna Reports
from
the monthly Bulletin of the Global Volcanism Network
KARANGETANG [Api Siau] Siau Island, Indonesia 2.47°N, 125.29°E; summit
elev. 1,784 m
During 17-23 September lava flows and lava avalanches rarely occurred at
Karangetang. Small white-colored emissions rose ~500 m above the main
crater and 50-200 m above Crater II. A 10- to 100-m-high “red reflection”
was visible above the volcano. Seismic activity decreased in comparison to
the previous week and was dominated by multiphase and avalanche
earthquakes. During 24-30 September seismic activity continued to decrease
and few lava avalanches were observed emanating from main crater. Plumes
rose 400 m above the summit of the main crater and 50-100 m above Crater
II. A 25-m-high “red reflection” was observed. The Alert Level remained at
3 (on a scale of 1-4).
Background. Karangetang (also known as Api Siau) lies at the northern end
of the island of Siau, N of Sulawesi, and contains five summit craters
strung along a N-S line. One of Indonesia's most active volcanoes,
Karangetang has had more than 40 recorded eruptions since 1675.
Twentieth-century eruptions have included frequent explosions, sometimes
accompanied by pyroclastic flows and lahars.
Source: Volcanological Survey of Indonesia
Karangetang Reports
from the monthly Bulletin of the Global Volcanism Network
KAVACHI Solomon Islands 9.02°S, 157.95°E; summit elev. -20 m (submarine)
Kavachi erupted daily during August through mid-September. During August
ash and volcanic projectiles were observed rising 400 m above sea level and
the glow from the volcano was visible from the coast of Gatokae Island, 32
km away.
Background. Kavachi, one of the most active submarine volcanoes in the SW
Pacific, occupies an isolated position in the Solomon Islands far from
major aircraft and shipping lanes. Kavachi, sometimes referred to as Rejo
te Kvachi ("Kavachi's oven"), is located S of Vangunu Island only 30 km N
of the site of subduction of the Indo-Australian plate beneath the Pacific
plate. The shallow submarine basaltic-to-andesitic volcano has produced
ephemeral islands up to 150 m long at least eight times since its first
recorded eruption during 1939. The roughly conical volcano rises from water
depths of 1.1-1.2 km on the N and greater depths to the S.
Source: The Wilderness Lodge http://www.thewildernesslodge.org/kavachi.htm
Kavachi Reports <
http://www.volcano.si.edu/gvp/volcano/region05/bougain/kavachi/var.htm>
from the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
Lava flows from the W of the active flow field began to enter the ocean at
a new area during the evening of 28-29 September. The ocean entry was
located S of the former site of Komoamoa camping area. By 30 September a
new lava bench and an adjacent black sand beach had begun to form. Lava
continued to flow into the ocean at the E Kupapa`u entry, although the
overall size of the entry had diminished. Surface lava flows were visible
above and on the Pulama pali scarp. The lava flows W and E of the flow
field that had been active for the past couple of weeks had mostly crusted
over. Generally, volcanic tremor remained at moderate-to-low levels at
Kilauea's summit and Pu`u `O`o. Background tremor at Pu`u `O`o was
interrupted at intervals of ten's of minutes to an hour or two, by
short-lived bursts of relatively vigorous tremor. Tiltmeters across the
volcano showed no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
MANAM offshore New Guinea, Papua New Guinea 4.10°S, 145.06°E; summit elev.
1,807 m
Volcanic activity at Manam during September was very low. Occasional
emissions of weak-to-moderate volumes of thin white vapor were visible at
Main Crater. Southern Crater emitted very small volumes of thin white vapor.
Background. The 10-km-wide island of Manam is of one of Papua New Guinea's
most active volcanoes. Four large radial valleys extend from the
unvegetated summit of the conical 1,807-m-high stratovolcano to its lower
flanks. These "avalanche valleys," regularly spaced 90 degrees apart,
channel lava flows and pyroclastic avalanches that have sometimes reached
the coast. Five satellitic centers are located near the island's shoreline.
Two summit craters are present; both are active, although most historical
eruptions have originated from the southern crater, concentrating eruptive
products during the past century into the SE avalanche valley. Frequent
historical eruptions have been recorded since 1616.
Source: Rabaul Volcanological Observatory
Manam Reports <
http://www.volcano.si.edu/gvp/volcano/region05/offshore/manam/var.htm> from
the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
During 17-30 September incandescent lava avalanches traveled SW primarily
down the Lamat, Senowo, and Bebeng rivers to a maximum run-out distance of
2.5 km. During 17-23 September 51 lava avalanches were observed.
Temperatures at Gendol Crater increased from 590-595 ºC the previous week
to 602-617 ºC during 17-23 September and to 598-618 ºC during 24-30
September. Avalanche earthquakes, which dominated the seismicity, increased
in comparison to the previous week.
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Merapi Reports
from
the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC 5 hours)
During the week, volcanic activity at Popocatépetl consisted of small
emissions of steam, gas, and minor amounts of ash, and episodes of harmonic
tremor. Pilots reported that a steam emission rose 4 km above the volcano
on 26 September at 1000.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html,
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
RABAUL New Britain Island, Papua New Guinea 4.271°S, 152.203°E; summit
elev. 688 m
During 10-30 September summit activity at Tavurvur, a stratovolcano of the
Rabaul Caldera, was very low. During the report period very
small-to-moderate amounts of steam were emitted from the active vent and
low-frequency volcanic earthquakes decreased. After the 11th seismic
activity was relatively low, except for a slight increase on the 16th. Very
slow deflation began on 20 September.
Background. The low-lying Rabaul caldera on the tip of the Gazelle
Peninsula at the NE end of New Britain forms a broad sheltered harbor. The
outer flanks of the 688-m-high asymmetrical pyroclastic shield volcano are
formed by thick pyroclastic-flow deposits. The 8 x 14 km caldera is widely
breached on the E, where its floor is flooded by Blanche Bay.Two major
Holocene caldera-forming eruptions at Rabaul took place as recently as
3,500 and 1,400 years ago. Three small stratovolcanoes lie outside the
northern and NE caldera rims. Post-caldera eruptions built
basaltic-to-dacitic pyroclastic cones on the caldera floor near the NE and
western caldera walls. Several of these, including Vulcan cone, which was
formed during a large eruption in 1878, have produced major explosive
activity during historical time. A powerful explosive eruption in 1994
occurred simultaneously from Vulcan and Tavurvur volcanoes and forced the
temporary abandonment of Rabaul city.
Source: Rabaul Volcanological Observatory
Rabaul Reports
from the Bulletin of the Global Volcanism Network
SEMERU Java, Indonesia 8.11°N, 112.92°E; summit elev. 3,676 m; All times
are local (= UTC + 8 hours)
According to the Darwin VAAC, a pilot reported observing an ash plume
rising 1-4 km above Semeru on 1 October at 1457. No ash was visible in
satellite imagery, possibly due to low-level meteorological clouds
obscuring the plume.
Background. Semeru is the highest volcano on Java and one of its most
active. The symmetrical stratovolcano rises abruptly to 3,676 m above
coastal plains to the S and lies at the southern end of a volcanic massif
extending N to the Tengger caldera. Semeru has been in almost continuous
eruption since 1967. Frequent small-to-moderate Vulcanian eruptions have
accompanied intermittent lava dome extrusion, and periodic pyroclastic
flows and lahars have damaged villages below the volcano. A major secondary
lahar on 14 May 1981 caused more than 250 deaths and damaged 16 villages.
Source: Darwin VAAC http://www.bom.gov.au/info/vaac/advisories.shtml
Semeru Reports
from the
monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev. 1,030 m
Volcanic activity at Soufrière Hills during 21-28 September was similar to
the previous week, except for a slight reduction in the number of hybrid
earthquakes. Seismicity continued to be dominated by bands of hybrid
earthquake swarms and increased rockfall activity with periodicities of
approximately 11 to 13 hours. The active lava dome continued to grow at a
moderate rate, producing rockfalls and small but energetic pyroclastic
flows that traveled E to the upper reaches of the Tar River Valley. Periods
of vigorous ash venting were associated with the hybrid-earthquake swarms.
Steam-and-ash clouds were visible on satellite imagery rising to ~500 m
above the volcano.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Sources: Montserrat Volcano Observatory http://www.mvo.ms/
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
from the monthly Bulletin of the Global Volcanism Network
TUNGURAHUA Ecuador 1.47°S, 78.44°W; summit elev. 5,023 m; All times are
local (= UTC 5 hours)
On 24 September at 1500 an eruption at Tungurahua produced an ash cloud
that rose ~2 km above the volcano and drifted to the W and SW. Roaring and
the sound of rockfalls were heard in several towns near the volcano. An
eruption on 25 September at 1230 produced a mushroom-shaped ash cloud that
rose 5 km above the volcano. The lower portion of the plume drifted to the
NW, while the higher portion remained fixed. Ash fell in the town of
Cotaló. During the evening of the 25th Strombolian activity was observed,
with rockfalls and incandescent volcanic fragments travelling to the W and
NW flanks of the volcano. After the eruption volcanic activity consisted of
low-level emissions of steam, gas, and ash. Small amounts of ash fell in
southern Quero.
Background. The steep-sided Tungurahua stratovolcano towers more than 3 km
above its northern base. It sits ~140 km S of Quito, Ecuador’s capital
city, and is one of Ecuador's most active volcanoes. Historical eruptions
have been restricted to the summit crater. They have been accompanied by
strong explosions and sometimes by pyroclastic flows and lava flows that
reached populated areas at the volcano's base. The last major eruption took
place from 1916 to 1918, although minor activity continued until 1925. The
latest eruption began in October 1999 and prompted an initial evacuation of
the town of Baños on the N side of the volcano.
Sources: Instituto Geofísico, http://www.epn.edu.ec/~igeo/index.html,
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Tungurahua Reports
from the monthly Bulletin of the Global Volcanism Network
ULAWUN New Britain, Papua New Guinea 5.04°S, 151.34°E; summit elev. 2,334
m; All times are local (= UTC + 10 hours)
Volcanic tremor occurred at Ulawun on 24 September at 2200 through 30
September. After the tremor peaked on the 27th at about 1000 it fluctuated
as it generally declined. By 30 September seismic activity was at moderate
levels. During 27-30 September a very slow deflationary trend was detected.
Background. The symmetrical basaltic-to-andesitic Ulawun stratovolcano is
the highest volcano of the Bismarck arc, and one of Papua New Guinea's most
frequently active. Ulawun rises above the N coast of New Britain opposite
Bamus volcano. The upper 1,000 m of the 2,334-m-high volcano is
unvegetated. A steep-walled valley cuts the NW side of the volcano, and a
flank lava-flow complex lies to the S of this valley. Historical eruptions
date back to the beginning of the 18th century. Twentieth-century
eruptions were mildly explosive until 1967, but after 1970 several larger
eruptions produced lava flows and basaltic pyroclastic flows, greatly
modifying the summit crater.
Source: Rabaul Volcanological Observatory
Ulawun Reports
http://www.volcano.si.edu/gvp/volcano/region05/new_brit/ulawun/var.htm from
the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Phone: (202) 357-2618 Fax: (202) 357-2476
mayberry@volcano.si.edu
URL: http://www.volcano.si.edu/gvp/usgs/
**********************************************************
Topic 2 of 99 [Geo]: Vulcanism
Response 607 of 997: Marcia (MarciaH) * Fri, Oct 5, 2001 (16:54) * 172 lines
USGS Volcano News for September 27 and October 4....the following articles
were written by USGS scientists at the USGS Hawaiian Volcano Observatory.
Volcano Watch - October 4, 2001
Mauna Loa will not push Kilauea into the ocean
"Volcano Watch" often responds to a question from an interested
citizen. A resident of Makawao, Maui, asked about the stability of Kilauea
and whether its south flank could slide away during an eruption of Mauna
Loa.
A concern about Kilauea's stability has been raised many times in the
past. The facts are often embellished, and the result is that the south
side of Kilauea is thought by some to be teetering on the brink of
wholesale collapse.
The facts are these. Part of the south flank of Kilauea is cut by
faults, known collectively as the Hilina fault system, which more or less
parallel the coastline. Hilina Pali, Poliokeawe Pali, and Holei Pali are
three of the better known faults. During large earthquakes, such as the
magnitude-7.9 in 1868 and the magnitude-7.2 in 1975, the faults drop down
suddenly. The observed dropping has been as much as 3.5 m (11.5 feet) in an
instant. Local tsunamis accompanied both of these earthquakes and
presumably others before them. Such a tsunami is very dangerous, because it
starts so close to shore.
The coastal part of the Hilina fault system is currently moving
seaward at a maximum observed rate of 8-10 cm (3-4 inches) each year. It is
also going up very slowly, or remaining at about the same elevation. This
works against the long-term subsidence of the entire island, which is
sinking because of its great weight, and the global rise in sea level.
Faulting will eventually drop the coastline again.
The southwest rift zone of Kilauea is quite stable, as is the south
flank of Kilauea, both east and west of the Hilina fault system. The only
areas moving much are the Hilina fault system and the sector between it and
the east rift zone.
Consequently, we cannot say that the entire south side of Kilauea is
currently unstable. That may be what some geophysical models say, but the
data tell us otherwise.
Another fact is that the seafloor topography around each Hawaiian
island reflects large-scale underwater landslides in the geologic past. The
seafloor is complex off the Hilina fault system, showing in places evidence
for landslides and in other places evidence for huge, almost horizontal
faults. We do not know if any submarine fault is currently moving, though a
long-term GPS experiment by Scripps Institution of Oceanography may resolve
this issue in a year or two.
Kilauea has had no massive landslide in the last 100,000 years, nor
is there evidence for a huge landslide anywhere in Hawai`i in that time.
The chances of the south side of Kilauea suddenly peeling away into the sea
are, in Dizzy Dean's famous words, "slim and none."
The questioner from Maui wanted to know if swelling of Mauna Loa
before or during an eruption might exert enough pressure against Kilauea to
push the south flank catastrophically into the ocean. We think this
unlikely. One of Mauna Loa's largest eruptions ever, in 1950, took place
along the southwest rift zone but had no impact on Kilauea. Mauna Loa is
currently not swelling much, if at all, and the western part of Kilauea
stands almost stock still. It is hard to imagine a situation in which the
slight swelling accompanying a future eruption of Mauna Loa would have any
major impact on Kilauea.
The Great Crack, part of Kilauea's southwest rift zone, is a large
eruptive fissure similar to several along the east rift zone, though longer
and wider. It is not undergoing unusual deformation and is not a gash where
the south flank of Kilauea is starting to tear away from the rest of the
island. Its name conjures up something mysterious, and so it has become
part of the lore about impending doom awaiting Kilauea.
As an earlier "Volcano Watch" put it, we need to be realistic and
worry about things that will happen within a time period of several
generations, such as the 1975 and 1868 earthquakes and tsunamis, and not
the things that happen in a time period of 100,000 years or more.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week. Lava moves away from the vent toward the
ocean in a network of tubes and descends Pulama pali in several separate
tubes. Many breakouts from the tube system feed surface flows above, on,
and below the pali in the coastal flats. During the night of September 28,
the western flow entered the ocean at Kamoamoa and is now building a new
bench. Lava also continues to enter the ocean in the area east of Kupapa`u
and provides visitors to the County's lava viewing area a great show.
The public is reminded that the benches of the two ocean entries are
very hazardous, with possible collapses of the new land. The steam clouds
are extremely hot, highly acidic, and laced with glass particles. Swimming
at the black sand beaches of the benches can be a blistering or even deadly
venture.
One earthquake was reported felt during the week ending on October 4.
Residents of Kapulena and Ahualoa felt an earthquake at 6:27 p.m. on
September 28. The magnitude-3.0 earthquake was located 11 km (6.6 mi)
east-northeast of Hawi at a depth of 30.7 km (18.4 mi).
Volcano Watch - September 27, 2001
When lava tubes go incontinent
A few days before the long Labor Day weekend, Hawai'i County
officials closed the newly opened Lava Viewing road because a surface lava
flow was threatening to cross it. Fortunately, the lava flow stopped just
after it crossed the road, and the road was reopened a few days later. For
some, it was a revelation that this could happen so soon. Others realized
it was business as usual.
Highway 130 and later roads laid along its course have been covered
many times in the last 15 years. The previous version of the road was
originally carved out of 1986-1991 vintage lavas to allow residents of
Royal Gardens access to their properties. Over the last several years, more
and more of that road has been covered by progressive eastward expansion of
the episode 55 flow field. The most recent surge of activity ended in May
2001, with the establishment of an ocean entry and the lava tube that feeds
it.
Of course, viewing the spectacle of lava entering the ocean is the
whole reason that the road was improved and reopened. That entry is made
possible by an established lava tube bringing a relatively constant supply
of lava from Pu'u 'O'o to the ocean.
Surface lava flows almost always originate from a rupture or blockage
of a lava tube. With the ocean-entry tube (what else would we call it?),
located only 700 m (2300 feet) from the end of the access road and the
start of the trail to the viewing area, some might expect frequent surface
flows to threaten the road and trail.
The Labor Day surface flow was not the first to break out so close to
the road in the last few months, but it was easily the biggest. For a few
days prior to closure of the viewing area, the flow had been advancing more
than 250 m (820 feet) per day. The area was closed by Hawai'i County Civil
Defense when the flow was less than 250 m (820 feet) from the road.
The Labor Day flow started in a portion of the lava tube, almost 2 km
(1.2 miles) uptube of the ocean entry, from where several small flows have
started in the last four months. Most of them last for a few days before
they stagnate. The Labor Day flow was active for about 2 weeks. Since Labor
Day, there have been other small surface flows and another large one that
flowed west and away from the lava-viewing road.
What makes some sections of a lava tube more prone to ruptures that
produce surface flows? In some tube systems, the answer would be that the
tube is weakest at sharp bends or abrupt changes in width. In the case of
the ocean-entry tube, we believe that the tube roof is very thin in the
areas of persistent ruptures. We know that because that same portion of the
tube was unusually visible in our aerial infrared scans conducted in May
right after the tube formed.
Infrared scanning is a method of visualizing heat; if the tube roof
were thin, it would allow lava heat to be conducted more easily to the
surface than in an area where the tube roof is thicker.
How much lava pressure would need to be exerted in order to break
through the tube roof? The answer to that is unknown. However, students of
the local construction industry know that some ancient tube roofs have
buckled when a 54-ton D-9 bulldozer rolls over them. Yet many of these
tubes survive.
We will not be surprised if surface flows threaten the viewing area a
few times a year. In fact, such occurrences should be viewed as another
kind of lava-viewing opportunity rather than a threat, especially in light
of the real threats we were all recently forced to acknowledge.
Eruption Update
Eruptive activity of Kilauea Volcano continued unabated at the Pu`u
`O`o vent during the past week. Lava moves away from the vent toward the
ocean in a network of tubes and descends Pulama pali in several separate
tubes. The two surface flows reported on the pali last week are now
crusted over. Many surface flow are active on the coastal flats, and one
is within 0.5 km (0.3 mi) of the ocean in the area west of Kamokuna. Lava
also continues to enter the ocean in the area east of Kupapa`u and provides
visitors to the viewing area a great show.
The public is reminded that the bench of the ocean entry is very
hazardous, with possible collapses of the new land. The steam cloud is
extremely hot, highly acidic, and laced with glass particles. Swimming at
the black sand beach of the bench can be a blistering or even deadly
venture.
There were no earthquakes reported felt during the week ending on
September 27.
This article was written by scientists at the U.S. Geological Survey's
Hawaiian Volcano Observatory.
Carolyn Bell
Acting Public Affairs Officer
U.S. Geological Survey
Mail Stop 119 National Center
Reston, VA 20192
Phone: 703-648-4463
Fax: 703-648-4466
Topic 2 of 99 [Geo]: Vulcanism
Response 608 of 997: Marcia (MarciaH) * Sat, Oct 6, 2001 (00:38) * 63 lines
*********************************************************
Montserrat Volcano Observatory: Weekly Activity Report
*********************************************************
From: Peter Dunkley
Montserrat Volcano Observatory
Montserrat, W.I.
Report for the period midday, 28 September 2001 to midday, 5 October
2001
Activity at the Soufrière Hills Volcano has escalated over the past
week. The seismograph network recorded 202 rockfall signals, 26 long
period events, 2 long period rockfalls and 451 hybrid events. No
volcanotectonic earthquakes were recorded.
Seismicity continued to be dominated by bands of activity. At the
beginning of the reporting period these were approximately 15 hours
apart, although towards the end of the week the periodicity had reduced
to approximately 9 hours. Some of these bands were dominated by swarms
of hybrid earthquakes and others by increased rockfall and pyroclastic
flow activity. Periods of vigorous ash-venting were associated with the
hybrid earthquake swarms.
The active lava dome continues to grow at a moderate rate. Numerous
pyroclastic flows were produced by material avalanching off the active
dome. For most of the reporting period these were small and were
confined to the upper reaches of the Tar River valley, but larger flows
occurred on the last two days of the reporting period. On the morning of
4 October there was sustained pyroclastic flow activity between 7.45 and
9.15 a.m., with at least three flows reaching the sea at the edge of the
Tar River delta. These flows were generated by a small-scale collapse on
the north side of the active lava dome, involving a volume of material
approximately equivalent to 10-15% of the dome. Sustained pyroclastic
flow activity occurred again on the morning of 5 October, starting at
about 8.45 a.m. and continuing at the time of reporting. During this
period numerous pyroclastic flows passed down the Tar River valley, one
of which reached the sea. These flows also appear to have originated
from the northern flank of the active lava dome. Dense clouds of ash
were generated during both these periods of elevated pyroclastic flow
activity and were carried westwards on the prevailing wind.
Gas monitoring was hampered by poor weather, although a sulphur dioxide
measurement of 418 tonnes per day was recorded on 1 October.
Mudflows occurred in the Belham Valley on several days during periods of
torrential rainfall.
The daytime entry zone (DTEZ) was temporarily closed on 4 October due to
increased activity and remains closed at present.
Activity could increase quite suddenly, with a dangerous situation
developing very quickly. Ash masks should be worn in ashy conditions.
The Belham Valley should be avoided during and after heavy rainfall due
to the possibility of mudflow activity. Residents of Montserrat and
visitors to the island are advised to tune into ZJB Radio for up-to-date
information on the volcano. Access to Plymouth, Bramble airport and
beyond is prohibited. There is a maritime exclusion zone around the
southern part of the island that extends two miles beyond the coastline
from Trant's Bay in the east to Garibaldi Hill on the west coast.
12 noon, Friday, 5 October 2001
Peter Dunkley
Montserrat Volcano Observatory
Mongo Hill
Montserrat
West Indies
Topic 2 of 99 [Geo]: Vulcanism
Response 609 of 997: Marcia (MarciaH) * Tue, Oct 9, 2001 (17:04) * 36 lines
*********************************
Piton de la Fournaise activity
*********************************
From: Thomas Staudacher
Observatoire Volcanologique du Piton de la Fournaise
5 October 2001
Since beginning of September we observe at Piton de la Fournaise volcano
increased seismic activity with about 10 seismic events per day. Since
beginning of October, seismicity further increased with up to 20 events per
day and slight tilt variations at Dolomieu Sud stations, simultaneous with
clear fissure opening at two stations on the north and on the south flank of
PdF, indicating slight inflation of summit.
Thomas Staudacher
---------------------------------------------------------------------
Thomas Staudacher
Observatoire Volcanologique du Piton de la Fournaise
97418 La Plaine des Cafres
La Réunion
---------------------------------------------------------------------
*********************************
Avachinsky ash simulation
*********************************
From: "Chretien,Daniel [CMC]"
Good day,
Trajectory model and Volcanic Ash simulation have been run tonight for the
AVACHINSKY Volcano for a simulated eruption that would occured at 1800Z on
October 5th 2001.
Both products are now available on the FTP site at :
ftp://ftp.cmc.ec.gc.ca/ftp/cmc/EER/special/current/
under the filename AVACHINSKY.xxxx.jpg for the Volcanic Ash simulation and
under avachinsky_tra.jpg for the trajectory model.
Cheers
Daniel Chrétien
Ops Supervisor
VAAC MONTREAL
Topic 2 of 99 [Geo]: Vulcanism
Response 610 of 997: Marcia (MarciaH) * Tue, Oct 9, 2001 (17:10) * 298 lines
**********************************
KVERT Information Release 62-01
**********************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 62-01
Saturday, October 06, 2001, 11:25 KDT (22:25 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
At 07:50 KDT on October 05 (18:50 UTC on October 04) an earthquake Ml >
1.5 occurred inside the edifice of the volcano accompanied by a small
gas-steam explosion (possibly with a small amount of ash) to a height of
less than 1000 m above the crater. Thin ashfall covered the southeastern
sector of the edifice. At 10:00 KDT on October 05 (21:00 UTC on October 04)
large gas and steam plumes were observed at the volcano.
Earthquakes Ml > 1.2-2.0 were registered from August 25 until this
time. On August 31 one EQ Ml >1.7, one EQ Ml > 2.2, and one EQ Ml > 2.6
were registered. On September 20 occurred one EQ Ml >1.7. On September 21
from 17:05 till 17:21 KDT a series of earthquakes was recorded from the
edifice of the volcano. The one Ml >2.5 was recorded at 4 km beneath the
volcano in this series. A 3-pixel thermal anomaly was clearly seen in an
image at 17:57 KDT (04:57 UTC) on October 22 at Avachinsky Volcano. An
observer from Radyugino settlement southeastward from P-K reported mudflows
about 50-100 m rolling down the summit the volcano. Mudflows were seen on
the southeastern slope of the cone each time after fresh snow fell. We
assume that the mudflows were caused by the intensive activity of a single
fumarole on the southeastern part of the summit.
Seismic activity at Avachinsky volcano was at background levels this
past week until October 05. On October 02-04, weak fumarolic activity was
observed at the volcano. On September 27 the volcano was quiet. At other
times, clouds obscured the volcano.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Unrest at the volcano continues. A lava dome is growing in the active
crater and, at any time with little warning, explosions could produce
pyroclastic flows and ash plumes that will rise as high as 7-10 km above
sea level and localized ashfall.
Seismic activity was above background levels this past week. Many weak
shallow earthquakes occurred within the volcano's edifice and many series
of weak local shallow seismic signals and local shallow seismic events
(possible collapses, avalanches) were registered.
The September 30 explosive eruption began at 13:23 KDT (00:23 UTC).
Observers in Klyuchi reported that at 13:23 KDT (00:23 UTC) explosions sent
an ash plume 2,500 m above the dome (5,000 m; 16,500 ft. ASL) and a short
pyroclastic flow. At 17:19 KDT (04:19 UTC) an ash plume rose 3,500 m above
the dome (6,000 m, 19,800 ft. ASL). At 17:55 KDT (04:55 UTC) an ash plume
rose 2,500 m above the dome (5,000 m, 16,500 ft. ASL). At 18:07 KDT (05:07
UTC) an ash plume rose 4,500 m above the dome (7,000 m, 23,100 ft. ASL).
And at 20:10 KDT (07:10 UTC) explosions sent an ash plume 9,000 m above the
dome (11,500 m, 38,000 ft. ASL). The ash plume extended to the east and to
the west, appearing as an umbrella cloud. The length of cloud was ~ 9 km.
Large pyroclastic flows moved ~ 5 km to the southeast.
Four MI >2 and fifteen MI >1.7 earthquakes were recorded on September
28-30. From 17:03 KDT until 21:00 KDT (04:03 UTC until 08:00 UTC) on
September 30 many continuous series of strong shallow earthquakes (A/Tmax
= 106.4·10(superscript: -6) mps) and volcanic tremor up to 0.8·10
(superscript: -6) mps were registered. According to visual data from
Klyuchi town, on September 28 a gas and steam plume rose 200 m above the
dome (2,650 m, 8,750 ft. ASL). A satellite image, at 07:28 KDT on September
28 (18:28 UTC on September 27), showed a 6-pixel thermal anomaly (maximum
band 3 temperature was 43.8 degrees C with -11 degrees C at background)
located in the active dome area. Satellite images at 18:10 KDT (05:10 UTC)
and at 18:26 KDT (05:26 UTC) on September 30 each showed 2 faint thermal
anomalies at the volcano as well as small traces of ash in 4-5 split window
imagery. Satellite images between 18:02 - 20:32 KDT (05:02 - 07:32 UTC) on
September 30 also confirmed the presence of a plume. A large low pressure
system and many patchy clouds over the volcano prevented clear views and
made the 4-5 split window data suspect in many areas. Band 4 imagery at
18:26 KDT (05:26 UTC) indicated that the plume was approximately 7 km ASL
and moved to the northeast.
Eleven MI >2 and nine MI >1.7 earthquakes were registered on October
01-04. The amplitudes of an intermittent weak spasmodic volcanic tremor
were, on average, 0.32x 10-6 mps (A/Tmax - 0.95x 10-6 mps) on October 01;
A/Tmax - 1.20x 10-6 mps on October 02. From 13:00 KDT on October 03 until
03:00 KDT on October 04 (from 00:00 until 14:00 UTC on October 03)
intermittent spasmodic volcanic tremor with an amplitude on average of
1.5·10(superscript: -6) mps was registered. The amplitude then dropped to,
on average, 0.7x10-6 mps.
Observers in Klyuchi town reported that at 16:41 KDT and at 16:54 KDT
(03:41 and at 03:54 UTC) on October 01, ash plumes rose 7,500 m and 7,000 m
above the dome (10,000 m; 33,000 ft. and 9,500 m, 31,400 ft. ASL). At 17:00
KDT (04:00 UTC) ash fell at Klyuchi. Thin ash for a few mm-layer covered
the town. At 18:30 KDT (05:30) a large ash cloud was observed for 15 km
near Klyuchi town. An ash cloud moved to the town. At 22:10 KDT (09:10 UTC)
a mushroom ash cloud to a height of ~ 3,000 m above the dome (5,500 m,
18,200 ft. ASL) stood to the east from the volcano. The ash cloud extended
10 km to the southeast. In this time a gas and steam plume rose 1,500 m
above the dome (4,000 m, 13,200 ft. ASL). At 12:52 KDT on October 02 (23:52
UTC on October 01) and at 13:09 KDT (00:09 UTC) on October 02 ash plumes
rose 1,000 m above the dome (3,500 m, 11,600 ft. ASL) and extended to the
east. Several ash explosions to a height of ~ 1,000 m above the dome (3,500
m, 11,600 ft. ASL) occurred during daylight on October 02. At 08:10 KDT on
October 03 (19:10 UTC on October 02) a gas and steam plume rose 350 m above
the dome (2,850 m, 9,400 ft. ASL). At 21:41 and at 22:32 KDT (08:41 and
09:32 UTC) on October 03 weak ash explosions were observed at the dome. The
hot lava at the summit of the dome was recorded at night on October 03. At
12:00 on October 05 a gas and steam plume rose 100 m above the dome (2,550
m, 8,400 ft. ASL). A satellite image showed that ash cloud was centered
over the volcano. At 07:57 KDT on October 1 (18:57 UTC on September 30) was
seen a small circular ash cloud, approximately 25 km in diameter, directly
over the volcano. The minimum Band 4 temperature was - 47 degrees C, and
Band 4-5 values were only as low as - 1.8. No indication of this ash cloud
was observed in a satellite image that morning, and no anomalous clouds had
drifted into GOES coverage, so it appears that the eruption cloud has
remained in the vicinity of the volcano. An image at 17:45 KDT (04:45 UTC)
on October 01 showed an attached ash-rich plume extending 50 km to the west
of the volcano. Minimum Band 4 temperature was -32 degrees C, corresponding
to approximately 5 km height in a standard subarctic atmosphere. An image
at 18:17 KDT (05:17 UTC) on October 01 showed a plume over the volcano
similar to that in the previous image (04:45 UTC), with the addition of a
two-pixel thermal anomaly ranging in temperature between 36 and 47 degrees
C, in a background of -5 degrees C.
The drifting ash cloud from the October 1 03:40 UTC explosion of the
volcano was visible in GMS satellite images at 01:30 KDT on October 02
(12:30 UTC on October 01). The cloud moved to the southwest and was last
seen about 225 km from the volcano over central Kamchatka near 55 N and 159
E. The AVHRR image from 07:35 KDT on October 02 (18:35 UTC on October 01)
showed no evidence of ash. A thermal anomaly was seen in this image (18:35
UTC), with one pixel at the dome having a maximum temperature of 24 degrees
C. Five other cooler pixels in the range of 3-5 degrees C were seen
extending to the south from the volcano, possibly due to cooling
pyroclastic activity. The background was in the range of -10 to -15 degrees
C. A thermal anomaly and low altitude plume at the volcano were seen in
images at 18:02 KDT (05:02 UTC) and at 17:24 KDT (04:24 UTC) on October 02.
The plume was approximately 80 km long, extending to the southeast over the
ocean, and had only slightly anomalous B4-5 values (minimum of -1 degrees
C) compared to the surroundings. Band 4 temperatures indicated it was very
low altitude. A thermal anomaly in the 05:02 UTC images was four pixels in
size, all at saturation in a background of 2 degrees C. AVHRR images at
17:01 KDT (04:01 UTC) and at 17:50 KDT (04:50 UTC) on October 03 each
reveal 2-6 pixel thermal anomalies at the volcano. Two of the six pixels
were at Band 3 saturation (~49.5 degrees C) within a background near -12
degrees C. A persistent thermal anomaly was observed in two daytime AVHRR
images from 17:26 KDT (04:26 UTC) and 17:53 KDT (04:53 UTC) on October 05.
The first image (04:26 UTC) had a 4-pixel anomaly with a maximum band 3
temperature of 39 degrees C in a background of about 7 degrees C. The
second image (04:53 UTC) has 4-pixel anomaly, with three of them saturated
at 50 degrees C.
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was above background levels on October 01-02 but it was at
background levels at all other times. Continuous, weak volcanic tremor was
registered on September 27-29. Volcanic tremor amplitudes were, on average,
0.22-0.32x 10-6 mps. Many series of shallow earthquakes were recorded on
October 01-02. Five MI >2 and six MI >1.7 earthquakes were registered.
Intermittent weak spasmodic volcanic tremor was recorded on October 01-03.
The volcanic tremor amplitudes were, on average, 0.19x 10-6 mps (A/Tmax -
0.28·10(superscript: -6) mps) on October 01 and 0.30x 10-6 mps on October
02-04.
According to visual data from Klyuchi town, at 08:10 KDT and at 11:50
KDT on October 01 (19:30 UTC and 22:50 UTC on September 30) gas and steam
plumes rose 1,000 m and 2,000 m above the crater (5,750 m, 19,000 ft. and
6,750 m, 22,300 ft. ASL) and extended 30 km and 15 km to the northwest. At
14:00 KDT (01:00 UTC) on October 01 a gas and steam plume rose 1,500 -
2,000 m above the crater (6,250 m, 20,600 ft. - 6,750 m, 22,300 ft. ASL)
and extended 10 km to the west. According to visual data from Kozyurevsk
village, at 17:30 KDT (04:30 UTC) on October 01 a gas and steam plume rose
800 m above the crater (5,550 m, 18,300 ft. ASL) and extended 5 km to the
south. Observers in Klyuchi town reported that at 08:30 KDT on October 02
(at 19:30 UTC on October 01) a gas and steam plume rose 300 m above the
crater (5,050 m, 16,700 ft. ASL) and extended 3 km to the southwest.
According to visual data from Kozyurevsk village, at 08:50 KDT on October
05 (19:50 UTC on October 04) a gas and steam plume rose 300 m above the
crater (5,050 m, 16,700 ft. ASL) and extended 3 km to the south. Observers
in Klyuchi town reported that at 12:00 KDT on October 05 (at 23:00 UTC on
October 04) a gas and steam plume rose 100 m above the crater (4,850 m,
16,000 ft. ASL). At other times, clouds obscured the volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity was registered under the volcano on September 27- October 04.
Observers in Kozirevsk village reported that at 08:10 KDT on September 30
(19:10 UTC on October 01) and 14:00 KDT (01:00 UTC) on October 01 a gas and
steam plume rose 500 m above the dome (3,400 m; 11,200 ft. ASL) and
extended to the east. At 17:30 (04:30 UTC) on October 01 and at 08:30 KDT
on October 02 (19:30 UTC on October 01) gas and steam plumes rose 300 m and
200 m above the dome (3,200 m; 10,600 ft. and 3,100 m 10,200 ft.ASL) and
extended 30 km and 3 km to the southwest. At other times, clouds obscured
the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at the volcano was at background levels on October 03 but no
seismicity was registered under the volcano at all other times. On October
02-04 the volcano was quiet. At other times, clouds obscured the volcano.
GORELY VOLCANO; 52o 33'N, 158o 02'E, Elevation 1,828 m;
MUTNOVSKY VOLCANO; 52o 27'N, 158o 12'E, Elevation 2,324 m
LEVEL OF CONCERN COLOR CODE FOR BOTH VOLCANOES IS GREEN.
Seismic activity at Gorely volcano was at background levels on October
01-03. At other times, no seismicity was registered under the volcano.
Seismic activity at Mutnovsky volcano was at background levels on September
27-28 but no seismicity was registered under the volcano at all other
times. On October 03 a gas-steam plume rose 400 m above the crater (2,700
m, 8,900 ft. ASL) of Mutnovsky volcano. The volcanoes were quiet on
September 27 and October 02-03. At other times, clouds obscured the
volcanoes.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatkan Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006 RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508 USA
E-mail: tlmurray@usgs.gov
907-786-7497
**********************************
KVERT Information Release 61-01-B
**********************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 61-01-B
Friday, October 5, 2001, 12:50 KDT (21:50 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
PREVIOUS LEVEL OF CONCERN COLOR CODE WAS GREEN.
Today, on October 05, 2001 at 7:50 local time an earthquake Ml = 1.5
occurred inside the edifice of the volcano accompanied by a small gas-steam
explosion (possibly with a small amount of ash) to a height of less than
1000 m above the crater. Thin ashfall covered the southeastern sector of
the edifice.
Earthquakes Ml³ 1.2-2.0 were registered from August 25, 2001 till this
time. On August 31 one EQ Ml³ 1.7, one EQ Ml³ 2.2, and one EQ Ml³ 2.6 were
registered. On September 20, 2001 occurred one EQ Ml³ 1.7. On September 21
from 17:05 till 17:21 KDT a series of earthquake was recorded from the
edifice of the volcano. The one Ml³ 2.5 was recorded at depth 4 km beneath
the volcano. A 3-pixel thermal anomaly was clearly seen in an AVHRR image
of Avachinsky Volcano at 0500 UTC on September 22.
An observer from Radyugino settlement southeastward from P-K reported about
mudflows about 50-100 m rolling down the summit the volcano. Mudflows were
seen on the southeastern slope of the cone each time after fresh snow fell.
We assume that mudflows were caused by the intensive activity of a single
fumarole on the southeastern part of the summit.
The last explosive eruption of Avachinsky volcano was in 1991. The eruption
lasted six days. The eruption was launched by two ash explosions directed
southwestward to P-K, and covered the town with a few mm-layer of ash.
Effusion of lava started 28 hours after the explosions. Further explosive
activity of the volcano occurred simultaneously with the effusions. As a
result of the eruption a lava cork filled the entire crater of the volcano.
According to our speculations of the further activity, we assume that it
could follow scenarios of the 1737 and 1827 eruptions. Either it could be a
large eruption accompanied by directed blasts with voluminous tephra,
debris avalanches, and mudflows. Or, gradual damage of the cork by various
earthquakes with small explosive events, mudflows, etc. The both of
scenarios could be possibly hazardous to the nearby farmer cottages
(dachas), Radyugino settlement and P-K.
PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS
Olga Girina
Kamchatka Volcanic Eruptions Response Team
IVGG, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006 RUSSIA
E-mail: girina@kcs.iks.ru
Tom Murray
Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508 USA
E-mail: tlmurray@usgs.gov
Topic 2 of 99 [Geo]: Vulcanism
Response 611 of 997: Marcia (MarciaH) * Tue, Oct 9, 2001 (17:16) * 19 lines
Kilauea Eruption Update 9 October 2001
with amazing photos
0530 October 9, 2001
The Kamoamoa entry area glows brightly this morning at 0444, and the East Kupapa`u ocean entry can be faintly seen in the clear predawn air. Yesterday helicopter pilots reported a notable breakout on the East Kupapa`u bench, delighting visitors to Hawai`i County's overlook. A large steam plume was coming from the East Kupapa`u entry yesterday.
Breakouts are taking place along the tube systems this morning. The largest continues to be the one along the east tube on Pulama pali. The entry tube system is also feeding lava onto the surface on the pali as well as in several spots on the coastal flat. The western, or perhaps the Kamoamoa, system likewise has small breakouts near the base of the pali.
Repeated below is the description of the Kamoamoa entry area yesterday.
___
A visit to the Kamoamoa entry this morning (Monday) between 0545 and 0710 shows an interesting change in activity. The east bench is no longer active and in fact is rapidly eroding under heavy surf. The west bench has extended 70 m farther west and is now about 190 m long parallel to the shoreline and extends 60-70 m out from the old sea cliff. The bench overall slopes westward, away from the main lava cascade of early last week. Most of the activity is confined to the new part of the west bench. Three small lava falls onto the bench were active, waxing and waning over time. Several breakouts were oozing on the bench itself, and more than five large, very active entries were feeding lava into the water from the front of the bench. Only one small explosion was observed at one of the entries. Quite a large volume of steam is rising from along the front of the bench, creating laze (lava haze, or hydrochloric acid mist) problems down the tradewind direction.
The west margin of the flow feeding lava over the sea cliff is quite active, and it looks as if the west margin of the flow will move even farther west during the day if conditions continue the same.
___
The crater of Pu`u `O`o is dark on this Tuesday morning, full of fume.
Volcanic tremor remains at a moderate to low level at both Kilauea's summit and Pu`u `O`o. At Pu`u `O`o, the background tremor is interrupted, at intervals of tens of minutes to a hour or two, by short-lived bursts of more vigorous tremor--possibly related to degassing events in the crater. Currently all tiltmeters on the volcano are showing normal trends; see the graphs near the end of this page.
http://hvo.wr.usgs.gov/kilauea/update/main.html
Topic 2 of 99 [Geo]: Vulcanism
Response 612 of 997: Marcia (MarciaH) * Tue, Oct 9, 2001 (18:47) * 47 lines
******************************************
Postdoc Opportunity - Penn State University
*******************************************
From: Barry Voight and Derek Elsworth
Penn State University is seeking applicants for a Postdoctoral position to
work on a multi-institutional sponsored project related to volcanic
processes on Montserrat. Candidates with strong backgrounds in volcano
deformation modeling, and geodetic inversion, and/or coupled
thermomechanical processes in geothermal systems, are encouraged to apply.
Completion of the Ph.D. by the beginning of the appointment is required.
Position is open immediately for one to three years.
Interested applicants should send a CV and the names and contact
information including mail addresses of three references to Professor
Barry Voight, Deike Building, University Park PA 16802 USA, or send email
to Barry Voight or Derek Elsworth .
Penn State University is an equal opportunity/affirmative action employer.
Women, minorities, veterans and disabled persons are encouraged to apply.
*********************************
textbook recommendations?
*********************************
From: "David A. Wark"
Greetings, all.
I'm planning a small (2-credit) course entitled "Volcanoes" for
Spring 2002, which will be directed primarily to non-geo majors, and
am seeking textbook recommendations. The Deckers book is a good
possibility - does anybody have any other suggestions to make?
Many thanks,
dave wark
(warkd@rpi.edu)
** Please respond to David directly at warkd@rpi.edu; do not Reply to the
volcano list. **
___________________________________________
David A. Wark
Dept of Earth & Environmental Sciences
Rensselaer Polytechnic Institute
Troy, New York 12180
office: 518-276-2674 fax: 518-276-6680
http://www.rpi.edu/~warkd/wark.html
Topic 2 of 99 [Geo]: Vulcanism
Response 613 of 997: Marcia (MarciaH) * Fri, Oct 12, 2001 (19:13) * 23 lines
********************************
Website beta-testers needed
********************************
From: Ed Venzke
The Global Volcanism Program website is nearing completion of a major
upgrade which will allow users to access a variety of information about
more than 1500 Holocene volcanoes, including their eruption histories,
directly from our database.
We are seeking beta-testers who can devote 1-2 hours using this site and
then provide feedback about any bugs or useability issues. Anyone
interested should send an email to webmaster@volcano.si.edu by October 17.
Those selected as testers will receive additional instructions later this
month.
_____________________________________________________________________
Ed Venzke
Global Volcanism Program, NMNH E-421 Tel: (202) 357-2822
Smithsonian Institution Fax: (202) 357-2476
Washington, DC 20560-0119 Email: venzke@volcano.si.edu
GVP Webmaster
______________________________________________________________________
Topic 2 of 99 [Geo]: Vulcanism
Response 614 of 997: Marcia (MarciaH) * Fri, Oct 12, 2001 (19:19) * 331 lines
GVP/USGS Weekly Volcanic Activity Report 3-9 October 2001
New Activity/Unrest: | Avachinsky, Russia | Fonualei, Tonga Islands | Piton
de la Fournaise, Réunion Island | Shiveluch, Russia |
Ongoing Activity: | Etna, Italy | Iwo-jima, Japan | Karangetang, Indonesia
| Kilauea, USA | Merapi, Indonesia | Popocatépetl, México | Semeru,
Indonesia | Soufrière Hills, Montserrat |
New Activity
AVACHINSKY Kamchatka Peninsula, Russia 53.255°N, 158.830°E; summit elev.
2,741 m; All times are local (= UTC + 12 hours)
During 25 August until at least 5 October several earthquakes, with
magnitudes between 1.2 and 2.5, were detected near Avachinsky. On 5
October at 0759 an earthquake inside the volcano’s edifice was accompanied
by a small gas-and-steam explosion with small amounts of ash that rose less
than 1 km above the crater. A thin layer of ash covered the SE sector of
the volcano’s edifice. The same day at 1000 larger gas-and-steam plumes
were observed rising above the volcano. Mudflows traveled 50-100 m down
Avachinsky’s SE slope. KVERT personnel believe the mudflows were caused by
intensive activity at a single fumarole on the SE side of the summit. On 5
October the Concern Color Code at Avachinsky was raised from Green to
Yellow .
Background. Avachinsky, one of Kamchatka's most active volcanoes, rises
above Petropavlovsk, Kamchatka's largest city. Avachinsky began to form
during the middle or late Pleistocene and is flanked to the SE by the
parasitic volcano Kozelsky, which has a large crater breached to the NE.
Avachinsky has a large horseshoe-shaped caldera, breached to the SW, that
was formed about 30,000-40,000 years ago when a major debris avalanche
buried an area of about 500 sq km to the S underlying the city of
Petropavlovsk. Reconstruction of the volcano took place in two stages, the
first of which began about 18,000 years before present (BP), and the second
7,000 years BP. Most eruptive products have been explosive, with
pyroclastic flows and hot lahars being directed primarily to the SW by the
breached caldera, although relatively short lava flows have been emitted.
The frequent historical eruptions of Avachinsky have been similar in style
and magnitude to previous Holocene eruptions.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm
Avachinsky Reports
from the monthly Bulletin of the Global Volcanism Network
FONUALEI Tonga Islands, Pacific Ocean 18.02°S, 174.325°W; summit elev. 200 m
The Laboratoire de Géophysique reported that explosive volcanic activity
may have occurred at Fonualei volcano during late September. On 27, 28, and
30 September numerous short T waves were received by the French Polynesian
Seismic Network. The preliminary location of the seismicity was determined
to be near the Tonga archipelago at 18.18°S (well constrained) and 174°W
(not as well constrained). The hydro-acoustic activity was interpreted to
be volcanic and explosive and could not be related to seismic activity at
the Tonga Trench. According to the Laboratoire de Géophysique, the
hydro-acoustic source could be near Fonualei volcano.
Background. A fumarolically active crater, breached to the SW with a fresh
lava flow extending to the sea, is located on the small, less than
2-km-wide island of Fonualei. In contrast to other islands of the Tonga
arc, Fonualei lavas are of dacitic composition. Eruptions have been
recorded since 1791, with major eruptions taking place in 1846 and 1847.
Lava flows occurred in both years; in 1846 explosive eruptions produced
large pumice rafts, and the following year ashfall damaged crops on the
island of Vavua, 56 km away and fell on vessels up to 950 km away. In 1939
explosive and effusive activity occurred from summit and flank vents, and
water spouts were reported 1.6 km SE of the island.
Source: Laboratoire de Géophysique
Fonualei Reports
from the monthly Bulletin of the Global Volcanism Network
PITON DE LA FOURNAISE Réunion Island, Indian Ocean 21.23°S, 55.71°E; summit
elev. 2,631 m
OVPDLF reported that beginning in early September an increase in seismic
activity was detected at Piton de la Fournaise, with ~10 seismic events per
day. Beginning in early October seismic activity further increased with up
to 20 events per day. Slight tilt variations detected S of Dolomieu Crater
occurred simultaneously with the opening of fissures at two stations on the
N and S flanks. The opening of the fissures indicated slight inflation at
the summit. Piton de la Fournaise last erupted during June and July 2001.
Background. The massive Piton de la Fournaise shield volcano on the island
of Réunion is one of the world's most active volcanoes. Most historical
eruptions have originated from the summit and flanks of Dolomieu, a
400-m-high lava shield that has grown within the youngest of three large
calderas. This latter caldera is 8 km wide and is breached to below sea
level on the eastern side. More than 150 eruptions, most of which have
produced fluid basaltic lava flows within the caldera, have been documented
since the 17th century.
Sources: Observatoire Volcanologique du Piton de la Fournaise
http://volcano.ipgp.jussieu.fr:8080/reunion/Eruptions.htm
Piton de la Fournaise Reports
from
the Bulletin of the Global Volcanism Network
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m; All times are local (= UTC + 12 hours)
During 28 September to 6 October a lava dome continued to grow in
Shiveluch’s active crater, and several eruptions produced ash and
steam-and-gas clouds. The highest reported ash clouds were produced from
eruptions on 1 October at 1641 and 1654. The ash plumes rose to 7 and 7.5
km above the volcano, respectively, and deposited a few millimeters of ash
in Klyuchi town, 46 km from the volcano. An eruption the same day at 2210
produced a mushroom-shaped ash cloud that rose to ~3 km above the volcano
and extended ~10 km SE. On the evening of 3 October incandescence was
visible at the dome. Thermal anomalies in the active dome area were visible
on satellite imagery. Spasmodic volcanic tremor and weak, shallow seismic
signals (possible collapses and avalanches) were registered. Shiveluch
remained at Concern Color Code Orange <
http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm>.
Background. The high, isolated massif of Shiveluch volcano (also spelled
Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group
and forms one of Kamchatka's largest and most active volcanoes. The
currently active Molodoy Shiveluch lava-dome complex was constructed during
the Holocene within a large horseshoe-shaped caldera formed by collapse of
the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large
eruptions of Shiveluch have occurred during the Holocene, making it the
most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent
collapses of lava-dome complexes, most recently in 1964, have produced
large debris avalanches whose deposits cover much of the floor of the
breached caldera. During the 1990s, intermittent explosive eruptions took
place from a new lava dome that began growing in 1980. The largest
historical eruptions from Shiveluch occurred in 1854 and 1964.
Source: Kamchatkan Volcanic Eruption Response Team via the Alaska Volcano
Observatory http://www.avo.alaska.edu/avo4/updates/kvertweekly.htm,
Shiveluch Reports
from the monthly Bulletin of the Global Volcanism Network
Ongoing Activity
ETNA Sicily, Italy 37.73°N, 15.00°E; summit elev. 3,315 m
During 4 and 5 October a large amount of degassing occurred at Northeast
Crater. Degassing at Bocca Nuova crater was occasionally accompanied by ash
emissions generated by the crumbling of the crater walls. Gas and “smoke”
were continuously emitted from the edges of the new crater located at 2.55
km elevation.
Background. Mount Etna, towering above Catania, Sicily's second largest
city, has one of the world's longest documented records of historical
volcanism, dating back to 1500 BC. Historical lava flows cover much of the
surface of this massive basaltic stratovolcano, the highest and most
voluminous in Italy. Two styles of eruptive activity typically occur at
Etna. Persistent explosive eruptions, sometimes with minor lava emissions,
take place from one or more of the three prominent summit craters: Central
Crater, Northeast Crater, and Southeast Crater. Flank eruptions, typically
with higher effusion rates, occur less frequently and originate from
fissures that open progressively downward from near the summit. A period
of more intense intermittent explosive eruptions from Etna’s summit craters
began in 1995.
Source: Charles Rivière's web site
http://perso.club-internet.fr/rivierec/septembre_2001.htm
Etna Reports
from
the monthly Bulletin of the Global Volcanism Network
IWO-JIMA Volcano Islands, Japan 24.75°N, 141.33°E; summit elev. 161 m
No volcanic activity was observed at Iwo-jima after 22 September, but
discolored seawater was occasionally visible along the SE coast until at
least 10 October. The area of discolored water was smaller than when the
submarine eruption began on 21 September. During 20 to about 28 September
many earthquakes and tremor were detected. Floating pumice collected along
Iwo-jima’s coast after the eruption is being analyzed to determine if the
eruption was magmatic or hydrothermal.
Background. Iwo-jima in the central Volcano Islands portion of the
Izu-Marianas arc lies within a 9-km-wide submarine caldera. The triangular,
8-km-long island narrows toward its SW tip. Iwo-jima (whose name means
"Sulfur Island") has undergone dramatic uplift for at least the past 700
years accompanying resurgent doming of the caldera. A shoreline landed upon
by Captain Cook's surveying crew in 1779 is now 40 m above sea level. The
roughly 160-m-high Moto-yama plateau on the NE half of the island consists
of submarine tuffs overlain by coral deposits and forms the island's high
point. Many NE-SW-trending fumaroles are located on Iwo-jima (also spelled
Io-jima), and temperature gradients are high. Numerous historical phreatic
eruptions, many from vents on the W and NW sides of the island, have
accompanied the remarkable uplift of Iwo-jima.
Sources: Japanese Meteorological Agency
http://www.kishou.go.jp/english/index.html, National Research Institute for
Earth Science and Disaster Prevention http://www.bosai.go.jp/
Iwo-jima Reports
from
the monthly Bulletin of the Global Volcanism Network
KARANGETANG [Api Siau] Siau Island, Indonesia 2.47°N, 125.29°E; summit
elev. 1,784 m
During 1-7 October there was an increase of deep volcanic earthquakes at
Karangetang. On 1 and 2 October incandescent lava avalanches traveled from
the main crater. Steam plumes rose 600 m above the main crater and 50-150 m
above Crater II. A 50-m-high “red reflection” was observed. The Alert Level
remained at 3 (on a scale of 1-4).
Background. Karangetang (also known as Api Siau) lies at the northern end
of the island of Siau, N of Sulawesi, and contains five summit craters
strung along a N-S line. One of Indonesia's most active volcanoes,
Karangetang has had more than 40 recorded eruptions since 1675.
Twentieth-century eruptions have included frequent explosions, sometimes
accompanied by pyroclastic flows and lahars.
Source: Volcanological Survey of Indonesia
Karangetang Reports
from the monthly Bulletin of the Global Volcanism Network
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
During the week, lava continued to flow into the ocean at the E Kupapa`u
ocean entry and at the new Kamoamoa entry and surface lava flows were
visible above and on the Pulama pali. The overall size of the E Kupapa`u
entry diminished, while activity was divided into two distinct areas at the
Kamoamoa entry; one to the E and one to the W. By 8 October lava was only
emitted from the W Kamoamoa entry area. Generally, volcanic tremor remained
at moderate-to-low levels at Kilauea’s summit and Pu`u `O`o. Background
tremor at Pu`u `O`o was interrupted at intervals of ten's of minutes to an
hour or two, by short-lived bursts of relatively vigorous tremor. Besides
small deflation at Kilauea’s summit on 28 September, tiltmeters across the
volcano showed no significant deformation.
Background. Kilauea, one of five coalescing volcanoes that comprise the
island of Hawaii, is one of the world’s most active volcanoes. Historically
its eruptions originate primarily from the summit caldera or along one of
the lengthy E and SW rift zones that extend from the caldera to the sea.
The latest Kilauea eruption began in January 1983 along the E rift zone.
The Pu`u `O`o-Kupaianaha eruption is now in its 18th year and 55th eruptive
episode. Since 1986, flows have traveled 11-12 km from the vents to the
sea, paving about 80 km2 of land on the S flank of Kilauea and building 205
hectares of new land. Intensive monitoring and field research by staff of
the US Geological Survey’s Hawaiian Volcano Observatory, established in
1912, make Kilauea one of Earth's best studied volcanoes.
Source: US Geological Survey Hawaiian Volcano Observatory
http://hvo.wr.usgs.gov/kilauea/update/
Kilauea Reports
from the monthly Bulletin of the Global Volcanism Network
MERAPI central Java, Indonesia 7.542°S, 110.442°E; summit elev. 2,947 m
During 1-7 October 59 incandescent lava avalanches were observed travelling
SW. The avalanches predominately traveled to the upstream portions of the
Sat River, and to a lesser extent down the Lamat and Senowo rivers to a
maximum run-out distance of 2.5 km. Seismicity was dominated by
approximately the same number and intensity of avalanche earthquakes as the
previous week. An average of 80 tons per day of SO2 was measured. The Alert
Level remained at 2.
Background. Merapi, one of Indonesia's most active volcanoes, lies in one
of the world's most densely populated areas and dominates the landscape
immediately N of the major city of Yogyakarta. The steep-sided modern
Merapi edifice, its upper part unvegetated due to frequent eruptive
activity, was constructed to the SW of an arcuate scarp cutting the eroded
older Batulawang volcano. Pyroclastic flows and lahars accompanying growth
and collapse of the steep-sided active summit lava dome have devastated
cultivated and inhabited lands on the volcano's western-to-southern flanks
and caused many fatalities during historical time. The volcano is the
object of extensive monitoring efforts by the Merapi Volcano Observatory of
the Volcanological Survey of Indonesia.
Source: Volcanological Survey of Indonesia
http://www.vsi.dpe.go.id/news/index.html
Merapi Reports
from
the monthly Bulletin of the Global Volcanism Network
POPOCATÉPETL México 19.02°N, 98.62°W; summit elev. 5,426 m; All times are
local (= UTC 5 hours)
During the week, Popocatépetl emitted small clouds of steam, gas, and minor
amounts of ash, and underwent episodes of harmonic tremor. According to
reports from the México City MWO to the Washington VAAC, a small eruption
on 9 October at 0712 produced an ash cloud that rose 2 km above the volcano
and drifted to the W.
Background. Popocatépetl, whose name is the Aztec word for smoking
mountain, towers to 5,426 m 70 km SE of México City and is North America's
second highest volcano. Frequent historical eruptions have been recorded
since the beginning of the Spanish colonial era. A small eruption on 21
December 1994 ended five decades of quiescence. Since 1996 small lava domes
have incrementally been constructed within the summit crater and destroyed
by explosive eruptions. Intermittent small-to-moderate gas-and-ash
eruptions have continued, occasionally producing ashfall in neighboring
towns and villages.
Photos (CENAPRED site): http://www.cenapred.unam.mx/boletines.html
Source: Centro Nacionale de Prevencion de Desastres
http://www.cenapred.unam.mx/boletines.html,
Popocatépetl Reports
from
the monthly Bulletin of the Global Volcanism Network
SEMERU Java, Indonesia 8.11°N, 112.92°E; summit elev. 3,676 m
VSI reported that as of 5 October volcanic activity at Semeru was at normal
levels, with a plume rising ~600 m above the volcano.
Background. Semeru is the highest volcano on Java and one of its most
active. The symmetrical stratovolcano rises abruptly to 3,676 m above
coastal plains to the S and lies at the southern end of a volcanic massif
extending N to the Tengger caldera. Semeru has been in almost continuous
eruption since 1967. Frequent small-to-moderate Vulcanian eruptions have
accompanied intermittent lava dome extrusion, and periodic pyroclastic
flows and lahars have damaged villages below the volcano. A major secondary
lahar on 14 May 1981 caused more than 250 deaths and damaged 16 villages.
Source: Darwin VAAC http://www.bom.gov.au/info/vaac/advisories.shtml
Semeru Reports
from the
monthly Bulletin of the Global Volcanism Network
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev.
1,030 m; All times are local (= UTC 4 hours)
During 28 September to 5 October volcanic activity at Soufrière Hills
increased in comparison to the previous week. Numerous pyroclastic flows
were produced by material avalanching off the lava dome, which continued to
grow in the summit crater at a moderate rate. Most of the pyroclastic flows
during the report period were small and confined to the upper reaches of
the Tar River Valley E of the volcano, but larger flows occurred on 4 and 5
October. On 4 October a small-scale lava-dome collapse (consisting of
10-15% of the dome’s volume) on the N side of the dome produced sustained
pyroclastic-flow activity between 0745 and 0915, with at least three flows
reaching the sea. Similar activity occurred on 5 October at 0845 until at
least midday. Dense ash clouds generated during both periods of elevated
pyroclastic-flow activity were visible on satellite imagery rising to ~1.8
km a.s.l. and drifting to the W. Seismicity continued to be dominated by
bands of hybrid earthquakes and rockfalls.
Background. The complex andesitic Soufrière Hills volcano occupies the
southern half of the island of Montserrat. The summit area consists
primarily of a series of lava domes emplaced along an ESE-trending zone.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but the first well-documented historical eruption on Montserrat
did not take place until 1995. Long-term small-to-moderate ash eruptions
were accompanied by lava-dome growth and pyroclastic flows that forced
evacuation of the southern half of the island and ultimately destroyed the
capital city of Plymouth, causing severe social and economic disruption.
The volcano is currently in a period of new dome growth.
Sources: Montserrat Volcano Observatory http://www.mvo.ms/
Washington VAAC http://www.ssd.noaa.gov/VAAC/messages.html
Soufrière Hills Reports
from the monthly Bulletin of the Global Volcanism Network
*********************************************************
Gari Mayberry
US Geological Survey/Global Volcanism Program
Smithsonian Institution
National Museum of Natural History E-421
Washington, DC 20560-0119
Topic 2 of 99 [Geo]: Vulcanism
Response 615 of 997: Marcia (MarciaH) * Mon, Oct 15, 2001 (20:25) * 152 lines
**********************************
KVERT Information Release 63-01
**********************************
From: avo-sci@usgs.gov
Kamchatkan Volcanic Activity
INFORMATION RELEASE 63-01
Friday, October 12, 2001, 13:42 KDT (00:42 UTC)
The following Release was received by the Alaska Volcano Observatory via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). All times
are Kamchatkan Daylight Time, 21 hours ahead of ADT.
SHEVELUCH VOLCANO; 56o 38'N, 161o 19'E; Elevation 2,447 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.
Unrest at the volcano continues. A lava dome is growing in the active
crater and, at any time with little warning, explosions could produce
pyroclastic flows and ash plumes that rise as high as 7-10 km above sea
level and localized ash fall.
Seismic activity was above background levels this past week. Many weak
shallow earthquakes occurred within the volcano's edifice and many series
of weak local shallow seismic signals and local shallow seismic events
(possible collapses, avalanches) were registered. Intermittent spasmodic
volcanic tremor with the amplitude, on average, 0.42x 10-6 mps was
registered on October 05. Five MI>2 and one MI>1.7 earthquakes were
recorded on October 08-10. From 17:00 KDT on October 09 until 13:00 KDT on
October 10 (from 04:00 UTC until 24:00 Oct. 09 UTC) intermittent spasmodic
volcanic tremor with the amplitude, on average, 0.56x 10-6 mps was
recorded. At other time on October 10 the amplitude of volcanic tremor, on
average, decreased to 0.26x 10-6 mps.
According to visual data from Klyuchi town, on October 05 a gas and
steam plume rose 100 m above the dome (2,550 m, 8,400 ft. ASL) and extended
10 km to the east. At 12:00 KDT on October 08 (23:00 UTC on October 07) and
at 08:30 KDT on October 09 (19:30 UTC on October 08) a gas and steam plume
rose 1,500 m above the dome (4,000 m, 13,200 ft. ASL). A 16:00 KDT (03:00
UTC) on October 08 a gas and steam plume rose 100 m above the dome (2,550
m, 8,400 ft. ASL). An ash plume 1,000 m above the dome (3,500 m, 11,600 ft.
ASL) occurred at the volcano at 15:34 KDT (02:34 UTC) on October 09. At
16:30 KDT in this day a gas and steam plume rose 2,000 m above the dome
(4,500 m, 14,900 ft. ASL). At 09:00 KDT on October 10 (20:00 UTC on October
09) a gas and steam plume rose 1,500 m above the dome (4,000 m, 13,200 ft.
ASL) and extended to the south. At 19:10 KDT (06:10 UTC) on October 10 a
gas and steam plume rose 1,200 m above the dome and extended 10 km to the
southeast. At 22:50 KDT (09:50 UTC) on October 10 was observed that lava
reflected light on the dome. At 08:55 KDT on October 11 (19:55 UTC on
October 10) a gas and steam plume rose 100 m above the dome (2,550 m, 8,400
ft. ASL). At 15:15 KDT and 16:10 KDT (02:15 UTC and 03:10 UTC) on October
11 explosions sent ash plumes 400 m above the dome (2,900 m, 9,600 ft. ASL)
and short pyroclastic flows. The ash plume extended to the east. At other
times, clouds obscured the volcano.
A faint 2-pixel thermal anomaly was observed in AVHRR data at the
active dome area at 07:18 KDT on October 07 (18:18 UTC on October 06). A
4-pixel thermal anomaly at the volcano (ranging from 22 to 49 degrees C -
two pixels at saturation, in a background of -10 degrees) and a steam plume
(it extended 45 km to the south) were seen in an image at 18:30 KDT (05:30
UTC) on October 08. A 3-pixel thermal anomaly (between 32 and 49 degrees C,
in a background of -5 degrees C) and a small gas-steam plume (it extended
30 km to the northwest) were observed in an image at 18:00 KDT (05:00 UTC)
on October 09. An intense 8-pixel thermal anomaly (3 saturated pixels
maximum value of 50 degrees C, with a background of -8 to -10 degrees C)
and an associated steam plume were observed in the AVHRR image at 17:37 KDT
(04:37 UTC) on October 10. A steam plume was recorded extending for about
50 km towards the southwest. A large thermal anomaly (seven pixels at 10 to
49 degrees C, in a background of -15 degrees C) was seen in the image at
07:24 KDT on October 11 (18:24 UTC on October 10).
KLYUCHEVSKOY VOLCANO; 56o 03'N, 160o 39'E; Elevation 4,750 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels. Continuous, spasmodic volcanic
tremor was registered on October 05-06 and 09-10. Volcanic tremor
amplitudes were, on average, 0.30x 10-6 mps on October 05; 0.18x 10-6 mps
on October 06; 0.26x 10-6 mps on October 09 and 0.51x 10-6 mps on October
10. According to visual data from Klyuchi town, on October 05 and 07-11 gas
and steam plumes rose 100-200 m above the crater (4,850-4,950 m,
16,000-16,300 ft. ASL). At 08:15 KDT on October 10 (19:15 UTC on October
09) a gas and steam plume rose 500 m above the crater (5,250 m, 17,300 ft.
ASL) and extended 5 km to the south. At other times, clouds obscured the
volcano.
BEZYMIANNY VOLCANO; 55o 58'N, 160o 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
No seismicity was registered under the volcano. Observers in Kozirevsk
village reported that on October 08 weak fumarolic activity was recorded at
the volcano. At 08:30 KDT on October 09 (19:30 UTC on October 08) and 17:30
KDT (04:30 UTC) October 09 gas and steam plumes rose 800 m and 100 m above
the dome (3,700 m and 3,000 m, 12,200 ft. and 9,900 ft. ASL). At 17:30 KDT
(04:30 UTC) on October 09 a gas and steam plume extended 10 km to the
south. At 08:00 KDT October 10 (19:00 UTC on October 09) and 17:15 KDT
(04:15 UTC) on October 10 gas and steam plumes rose 300 m and 200 m (3,200
m; 10,600 ft. and 3,100 m, 10,200 ft. ASL) and extended 15 km to the
southwest and to the west. On October 11 a weak gas and steam plume was
observed at the volcano. It extended to the southeast. At other times,
clouds obscured the volcano.
KARYMSKY VOLCANO; 54o 03'N, 159o 27'E; Elevation 1,486 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismic activity was at background levels.
AVACHINSKY VOLCANO; 53o 15'N, 158o 50'E; Elevation 2,751 m.
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.
Seismic activity was at background levels on October 06-11. At 08:50 KDT on
October 06 (19:50 UTC on October 05) fumarolic activity was observed over
the entire crater of the volcano. At 12:50 KDT on October 06 (23:50 UTC on
October 05) an intense gas-steam plume was recorded low over the crater.
The plume extended 10 km to the southeast. At 08:50 KDT on October 07
(19:50 UTC on October 06) an intense gas-steam plume rose 50 m over the
crater of the volcano and extended down-slope of the cone to the
south-southeast. At 10:45 KDT October 07 (21:45 UTC on October 06) an
intense gas-steam plume rose 500 m above the crater. At 12:50 KDT October
07 (23:50 UTC on October 06) an intensive gas-steam plume rose 50 m about
the crater of the volcano and extended 5 km to the southeast. At 17:00 KDT
(04:00 UTC) October 07 a gas-steam plume rose 200 m above the crater. On
October 09 a gas-steam plume rose low above the crater and extended 2-3 km
to the east. Weak fumarolic activity was recorded on October 10. At 09:40
KDT on October 11 (20:40 UTC on October 10) a gas-steam plume rose 200 m
and extended 5 km to the east. Weak fumarolic activity was observed on
October 11 also. At other times, clouds obscured the volcano. A satellite
image (the Band 6) on October 02 showed a broad area of warm ground that
appear to follow the rim of the crater, with a small area in the center of
the crater. The Band 7 data on October 02 showed hotter areas in the
southeast and southwest sides of the crater, and possibly on the north side
as well. A large, elongate cloud was recorded extending to the southeast
from the volcano at 18:30 KDT (05:30 UTC) on October 08.
KORYAKSKY VOLCANO; 53o19'N, 158o 41'E; Elevation 3,456 m
CURRENT LEVEL OF CONCERN COLOR CODE IS GREEN.
Seismicity at the volcano was at background levels on October 07-08 but no
seismicity was registered under the volcano at all other times. The volcano
was quiet or obscured by clouds this past week.
GORELY VOLCANO; 52o 33'N, 158o 02'E
