SI/USGS Weekly Volcanic Activity Report 4-10 February 2009

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**********************************************************
SI/USGS Weekly Volcanic Activity Report
4-10 February 2009
**********************************************************

Sally Kuhn Sennert - Weekly Report Editor
kuhns@xxxxxx
URL: http://www.volcano.si.edu/reports/usgs/


New Activity/Unrest: | Asama, Honshu | Redoubt, Southwestern Alaska |
Sakura-jima, Kyushu

Ongoing Activity: | Barren Island, Andaman Is | Chaitén, Southern
Chile | Colima, México | Dukono, Halmahera | Fuego, Guatemala |
Karymsky, Eastern Kamchatka | Kilauea, Hawaii (USA) | Popocatépetl,
México | Rabaul, New Britain | Sangay, Ecuador | Santa María,
Guatemala | Shiveluch, Central Kamchatka (Russia) | Soufrière Hills,
Montserrat | Tungurahua, Ecuador


The Weekly Volcanic Activity Report is a cooperative project between
the Smithsonian's Global Volcanism Program and the US Geological
Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday,
notices of volcanic activity posted on these pages are preliminary and
subject to change as events are studied in more detail. This is not a
comprehensive list of all of Earth's volcanoes erupting during the
week, but rather a summary of activity at volcanoes that meet criteria
discussed in detail in the "Criteria and Disclaimers" section.
Carefully reviewed, detailed reports on various volcanoes are
published monthly in the Bulletin of the Global Volcanism Network.

Note: Many news agencies do not archive the articles they post on the
Internet, and therefore the links to some sources may not be active.
To obtain information about the cited articles that are no longer
available on the Internet contact the source.


New Activity/Unrest


ASAMA Honshu 36.403°N, 138.526°E; summit elev. 2568 m

JMA reported that an eruption from Asama produced ash plumes that rose
to altitudes of 3-4 km (10,000-13,100 ft) a.s.l. during 9-10 February.
Ash fell in areas to the NE on 9 February.

Geologic Summary. Asama, Honshu's most active volcano, is located at
the junction of the Izu-Marianas and NE Japan arcs and has an
historical record dating back at least to the 11th century. The modern
cone of Maekake-yama is situated E of the horseshoe-shaped remnant of
an older andesitic volcano, Kurofu-yama, which was destroyed by a
late-Pleistocene landslide about 20,000 years before present (BP).
Growth of a dacitic and rhyolitic lava cone was accompanied by
pumiceous pyroclastic flows, the largest of which occurred about
14,000-11,000 years BP, and by growth of the Ko-Asama-yama lava dome
on the E flank. Maekake-yama is probably only a few thousand years
old, but has had several major Plinian eruptions, the last two of
which occurred in 1108 and 1783 AD.

Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/indexe.html


REDOUBT Southwestern Alaska 60.485°N, 152.742°W; summit elev. 3108 m

AVO reported that during 4-10 February seismic activity at Redoubt
fluctuated but remained elevated well above background levels. On 7
February, aerial observers reported continued steaming from an area
around the 1989-90 lava dome and water discharge along the Drift
Glacier. Clear web camera views during 7-9 February showed small steam
plumes.

Geologic Summary. Redoubt is a 3108-m-high glacier-covered
stratovolcano with a breached summit crater in Lake Clark National
Park about 170 km SW of Anchorage. Next to Mount Spurr, Redoubt has
been the most active Holocene volcano in the upper Cook Inlet.
Collapse of the summit of Redoubt 10,500-13,000 years ago produced a
major debris avalanche that reached Cook Inlet. Holocene activity has
included the emplacement of a large debris avalanche and clay-rich
lahars that dammed Lake Crescent on the south side and reached Cook
Inlet about 3500 years ago. Eruptions during the past few centuries
have affected only the Drift River drainage on the north. Historical
eruptions have originated from a vent at the north end of the
1.8-km-wide breached summit crater. The 1989-90 eruption of Redoubt
had severe economic impact on the Cook Inlet region and affected air
traffic far beyond the volcano.

Source: Alaska Volcano Observatory (AVO) http://www.avo.alaska.edu/


SAKURA-JIMA Kyushu 31.585°N, 130.657°E; summit elev. 1117 m

JMA reported that Sakura-jima erupted explosively eight times during
1-2 February; bombs were deposited as far away as 800 m from the Showa
crater (on the E slope of Minami-dake, or "south mountain," at an
elevation of about 800 m). JMA raised the Alert Level from 2 to 3 on 2
February. Based on information from JMA, the Tokyo VAAC reported that
during 4-5 February explosions and eruptions produced plumes that rose
to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted SE. On
9 February a pilot reported that an ash plume rose to an altitude of
2.4 km (8,000 ft) a.s.l. and drifted SE.

Geologic Summary. Sakura-jima, one of Japan's most active volcanoes,
is a post-caldera cone of the Aira caldera at the northern half of
Kagoshima Bay. Eruption of the voluminous Ito pyroclastic flow was
associated with the formation of the 17 x 23-km-wide Aira caldera
about 22,000 years ago. The construction of Sakura-jima began about
13,000 years ago and built an island that was finally joined to the
Osumi Peninsula during the major explosive and effusive eruption of
1914. Activity at the Kita-dake summit cone ended about 4,850 years
ago, after which eruptions took place at Minami-dake. Frequent
historical eruptions, recorded since the 8th century, have deposited
ash on Kagoshima, one of Kyushu's largest cities, located across
Kagoshima Bay only 8 km from the summit. The largest historical
eruption took place during 1471-76.

Sources: Japan Meteorological Agency (JMA)
http://www.jma.go.jp/jma/indexe.html,
Tokyo Volcanic Ash Advisory Center (VAAC)
http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html


Ongoing Activity


BARREN ISLAND Andaman Is 12.278°N, 93.858°E; summit elev. 354 m

Based on analysis of satellite imagery, SIGMET notices, and pilot
observations, the Darwin VAAC reported that on 5 February an ash plume
from Barren Island rose to an altitude of 3 km (10,000 ft) a.s.l. and
drifted SSE.

Geologic Summary. Barren Island, a possession of India in the Andaman
Sea about 135 km NE of Port Blair in the Andaman Islands, is the only
historically active volcano along the N-S-trending volcanic arc
extending between Sumatra and Burma (Myanmar). The 354-m-high island
is the emergent summit of volcano that rises from a depth of about
2,250 m. The small, uninhabited 3-km-wide island contains a roughly
2-km-wide caldera with walls 250-350 m high. The caldera, which is
open to the sea on the W, was created during a major explosive
eruption in the late Pleistocene that produced pyroclastic-flow and
-surge deposits. The morphology of a fresh pyroclastic cone that was
constructed in the center of the caldera has varied during the course
of historical eruptions. Lava flows fill much of the caldera floor and
have reached the sea along the western coast during historical
eruptions.

Source: Darwin Volcanic Ash Advisory Center (VAAC)
http://www.ssd.noaa.gov/VAAC/OTH/AU/messages.html


CHAITEN Southern Chile 42.833°S, 72.646°W; summit elev. 1122 m

Based on SIGMET notices, analysis of satellite imagery, reports from
the Puerto Montt Flight Information Region (FIR), and web camera
views, the Buenos Aires VAAC reported that on 4, 6, and 7 February ash
plumes from Chaitén rose to altitudes 2-3 km (6,500-10,000 ft) a.s.l.
and drifted N, NE, and SE.

Geologic Summary. Chaitén is a small, glacier-free caldera with a
Holocene lava dome located 10 km NE of the town of Chaitén on the Gulf
of Corcovado. A pyroclastic-surge and pumice deposit considered to
originate from the eruption that formed the elliptical 2.5 x 4 km wide
summit caldera was dated at about 9400 years ago. A rhyolitic,
962-m-high obsidian lava dome occupies much of the caldera floor.
Obsidian cobbles from this dome found in the Blanco River are the
source of prehistorical artifacts from archaeological sites along the
Pacific coast as far as 400 km away from the volcano to the north and
south. The caldera is breached on the SW side by a river that drains
to the bay of Chaitén, and the high point on its southern rim reaches
1122 m.

Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
http://www.ssd.noaa.gov/VAAC/OTH/AG/messages.html


COLIMA México 19.514°N, 103.62°W; summit elev. 3850 m

During 3-10 February, white and gray plumes from Colima rose to
altitudes of 3.9-4.9 km (12,800-16,100 ft) a.s.l. On 4 and 6 February,
incandescent material was ejected 50 m above the summit.

Geologic Summary. 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 Volcán de
Colima on the S. Volcán de Colima (also known as Volcán 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 repeatedly from both
the Nevado and Colima cones, and have produced a thick apron of
debris-avalanche deposits on three sides of the complex. Frequent
historical eruptions date back to the 16th century. Occasional major
explosive eruptions (most recently in 1913) have destroyed the summit
and left a deep, steep-sided crater that was slowly refilled and then
overtopped by lava dome growth.

Source: Gobierno del Estado de Colima
http://www.colima-estado.gob.mx/2006/seguridad/indvolcan.php


DUKONO Halmahera 1.68°N, 127.88°E; summit elev. 1335 m

Based on analysis of satellite imagery, the Darwin VAAC reported that
during 9-10 February ash plumes from Dukono rose to an altitude of 3
km (10,000 ft) a.s.l. and drifted E and SE.

Geologic Summary. Reports from this remote volcano in northernmost
Halmahera are rare, but Dukono has been one of Indonesia's most active
volcanoes. More-or-less continuous explosive eruptions, sometimes
accompanied by lava flows, occurred from 1933 until at least the
mid-1990s, when routine observations were curtailed. During a major
eruption in 1550, a lava flow filled in the strait between Halmahera
and the N-flank cone of Gunung Mamuya. Dukono is a complex volcano
presenting a broad, low profile with multiple summit peaks and
overlapping craters. Malupang Wariang, 1 km SW of Dukono's summit
crater complex, contains a 700 x 570 m crater that has also been
active during historical time.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)
http://www.ssd.noaa.gov/VAAC/OTH/AU/messages.html


FUEGO Guatemala 14.473°N, 90.880°W; summit elev. 3763 m

On 6, 8, and 10 February, INSIVUMEH reported that multiple explosions
from Fuego produced ash plumes that rose to altitudes of 4.1-5.4 km
(13,500-17,700 ft) a.s.l. and drifted S and SW. Ashfall was reported
in areas downwind. Some explosions produced rumbling sounds and
constant avalanches of blocks descended the flanks. On 8 February,
explosions were accompanied by shock waves that were detected 10-15 km
away.

Geologic Summary. Volcán Fuego, one of Central America's most active
volcanoes, is one of three large stratovolcanoes overlooking
Guatemala's former capital, Antigua. The scarp of an older edifice,
Meseta, lies between 3,763-m-high Fuego and its twin volcano to the N,
Acatenango. Construction of Meseta volcano continued until the late
Pleistocene or early Holocene, after which growth of the modern Fuego
volcano continued the southward migration of volcanism that began at
Acatenango. Frequent vigorous historical eruptions have been recorded
at Fuego since the onset of the Spanish era in 1524, and have produced
major ashfalls, along with occasional pyroclastic flows and lava
flows. The last major explosive eruption from Fuego took place in
1974, producing spectacular pyroclastic flows visible from Antigua.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia,
e Hidrologia (INSIVUMEH) http://www.insivumeh.gob.gt/


KARYMSKY Eastern Kamchatka 54.05°N, 159.45°E; summit elev. 1536 m

KVERT reported that seismic activity at Karymsky was above background
levels during 1-4 February and at background levels on the other days
during 30 January-6 February. Analysis of satellite imagery revealed a
weak thermal anomaly in the crater on 30 January; clouds prohibited
views during the rest of the reporting period. The Level of Concern
Color Code remained at Orange.

Geologic Summary. Karymsky, the most active volcano of Kamchatka's
eastern volcanic zone, is a symmetrical stratovolcano constructed
within a 5-km-wide caldera that formed about 7,600-7,700 radiocarbon
years ago. Construction of the Karymsky stratovolcano began about
2,000 years later. The latest eruptive period began about 500 years
ago, following a 2,300-year quiescence. Much of the cone is mantled by
lava flows less than 200 years old. Historical eruptions have been
Vulcanian or Vulcanian-Strombolian with moderate explosive activity
and occasional lava flows from the summit crater. Most seismicity
preceding Karymsky eruptions has originated beneath Akademia Nauk
caldera, which is located immediately S of Karymsky volcano and
erupted simultaneously with Karymsky in 1996.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
http://www.kscnet.ru/ivs/kvert/index_eng.php


KILAUEA Hawaii (USA) 19.421°N, 155.287°W; summit elev. 1222 m

HVO reported that during 4-10 February lava flowed SE from underneath
Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex
through a lava tube system, reaching the Waikupanaha and Waha'ula
ocean entries. On 7 and 8 February, multiple explosions at the ocean
entry were seen. On 9 February, booming noises and explosions were
noted at the ocean entry; observers reported lava bubble bursts at
15-30 minute intervals. Seismicity and later observations indicated
that the bench had collapsed. Incandescence originated from the Prince
lobe, the flow that feeds the Waha'ula ocean entry. Thermal anomalies
suggesting surface flows were noted on the coastal plain and on the
pali.

The vent in Halema'uma'u crater continued to produce a predominantly
white plume that drifted mainly SW; the plume turned brown on 5 and 7
February. Small amounts of tephra were routinely collected.
Incandescence was intermittently seen from the vent, and sounds
resembling rushing gas and rockfalls were sometimes heard in the
vicinity of the crater. Geologists looked into the vent on 4 and 6
February and saw lava rising and falling about 115-120 m below the
vent rim. The sulfur dioxide emission rate at the summit was 900
tonnes per day on 4 and 9 February, and 500 tonnes on 5 February; the
2003-2007 average rate was 140 tonnes per day.

Geologic Summary. Kilauea, one of five coalescing volcanoes that
comprise the island of Hawaii, is one of the world's most active
volcanoes. Eruptions at Kilauea 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. About 90% of the surface of Kilauea is
formed of lava flows less than about 1,100 years old; 70% of the
volcano's surface is younger than 600 years. A long-term eruption from
the East rift zone that began in 1983 has produced lava flows covering
more than 100 sq km, destroying nearly 200 houses and adding new
coastline to the island.

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
http://hvo.wr.usgs.gov/


POPOCATEPETL México 19.023°N, 98.622°W; summit elev. 5426 m

CENAPRED reported that emissions of steam and gas from Popocatépetl
were visible during 4-10 February; the plumes occasionally contained
slight amounts of ash. On 6 February, an ash plume rose 800 m above
the crater at 0839, and was followed by 75 minutes of increased
seismicity.

Geologic Summary. Popocatépetl, whose name is the Aztec word for
smoking mountain, towers to 5,426 m 70 km SE of Mexico 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.

Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
http://www.cenapred.unam.mx/es/


RABAUL New Britain 4.271°S, 152.203°E; summit elev. 688 m

Based on analysis of satellite imagery, the Darwin VAAC reported that
on 9 February an ash plume from Rabaul caldera's Tavurvur cone rose to
an altitude of 3 km (10,000 ft) a.s.l. and drifted SE.

Geologic Summary. 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: Darwin Volcanic Ash Advisory Centre (VAAC)
http://www.ssd.noaa.gov/VAAC/OTH/AU/messages.html


SANGAY Ecuador 2.002°S, 78.341°W; summit elev. 5230 m

Based on pilot observations, the Washington VAAC reported that on 9
February a plume from Sangay rose to an altitude of 7.9 km (26,000 ft)
a.s.l. No ash was identified on satellite imagery, but meteoric clouds
were also present in the area.

Geologic Summary. The isolated Sangay volcano, located E of the Andean
crest, is the southernmost of Ecuador's volcanoes, and its most
active. It has been in frequent eruption for the past several
centuries. The steep-sided, 5,230-m-high glacier-covered volcano grew
within horseshoe-shaped calderas of two previous edifices, which were
destroyed by collapse to the E, producing large debris avalanches that
reached the Amazonian lowlands. The modern edifice dates back to at
least 14,000 years ago. Sangay towers above the tropical jungle on the
E side; on the other sides flat plains of ash from the volcano have
been sculpted by heavy rains into steep-walled canyons up to 600 m
deep. The earliest report of an historical eruption was in 1628. More
or less continuous eruptions were reported from 1728 until 1916, and
again from 1934 to the present. The more or less constant eruptive
activity has caused frequent changes to the morphology of the summit
crater complex.

Source: Washington Volcanic Ash Advisory Center (VAAC)
http://www.ssd.noaa.gov/VAAC/messages.html


SANTA MARIA Guatemala 14.756°N, 91.552°W; summit elev. 3772 m

Based on analysis of satellite imagery, the Washington VAAC reported
that on 4 February multiple ash puffs from Santa María's Santiaguito
lava dome complex drifted W. On 6 February, INSIVUMEH reported that
fumarolic plumes rose 80 m above the crater and rifted S and SW.
Explosions produced plumes that rose to altitudes of 2.8-3.1 km
(9,200-10,200 ft) a.s.l. and also drifted SW. Ashfall was reported in
areas downwind.

Geologic Summary. Symmetrical, forest-covered Santa María volcano is
one of a chain of large stratovolcanoes that rises dramatically above
the Pacific coastal plain of Guatemala. The stratovolcano has a
sharp-topped, conical profile that is cut on the SW flank by a large,
1-km-wide crater, which formed during a catastrophic eruption in 1902
and extends from just below the summit to the lower flank. The
renowned Plinian eruption of 1902 followed a long repose period and
devastated much of SW Guatemala. The large dacitic Santiaguito
lava-dome complex has been growing at the base of the 1902 crater
since 1922. Compound dome growth at Santiaguito has occurred
episodically from four westward-younging vents, accompanied by almost
continuous minor explosions and periodic lava extrusion, larger
explosions, pyroclastic flows, and lahars.

Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia,
e Hidrologia (INSIVUMEH) http://www.insivumeh.gob.gt/,
Washington Volcanic Ash Advisory Center (VAAC)
http://www.ssd.noaa.gov/VAAC/messages.html


SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m

KVERT reported that seismic activity at Shiveluch was above background
levels during 30 January-6 February. Based on interpretations of
seismic data, ash plumes likely rose to altitudes of 5.3 km (17,400
ft) a.s.l. Lava flows continued to be active on the S and N flanks.
Weak gas-and-steam activity was noted on 30 January and 1 February.
Analysis of satellite imagery revealed a large thermal anomaly on the
lava dome during 30 January-2 February, and on 5 February. The Level
of Concern Color Code remained at Orange.

Based on information from KEMSD, the Tokyo VAAC reported that an
eruption on 7 February produced a plume that rose to an altitude of
4.9 km (16,000 ft) a.s.l.

Geologic Summary. 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.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT)
http://www.kscnet.ru/ivs/kvert/index_eng.php,
Tokyo Volcanic Ash Advisory Center (VAAC)
http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html


SOUFRIERE HILLS Montserrat 16.72°N, 62.18°W; summit elev. 915 m

MVO reported that during 30 January-6 February activity from the
Soufrière Hills lava dome increased slightly, although seismic
activity was low. Three rockfalls were detected. On 5 February, one
small pyroclastic flow that originated in a gully on the N side of the
lava dome traveled less than 1 km and stopped in Tyre's Ghaut (NW).
The Hazard Level remained at 4.

Geologic Summary. The complex dominantly 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. English's Crater, a 1-km-wide crater
breached widely to the E, was formed during an eruption about 4,000
years ago in which the summit collapsed, producing a large submarine
debris avalanche. Block-and-ash flow and surge deposits associated
with dome growth predominate in flank deposits at Soufrière Hills.
Non-eruptive seismic swarms occurred at 30-year intervals in the 20th
century, but with the exception of a 17th-century eruption that
produced the Castle Peak lava dome, no historical eruptions were
recorded on Montserrat until 1995. Long-term small-to-moderate ash
eruptions beginning in that year were later 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 major social and economic disruption.

Source: Montserrat Volcano Observatory (MVO) http://www.mvo.ms/


TUNGURAHUA Ecuador 1.467°S, 78.442°W; summit elev. 5023 m

The IG reported that during 4-8 February visual observations of
Tungurahua were limited due to cloud cover; steam-and-ash plumes rose
0.5-1 km above the summit during 7 and 9-10 February. Plumes drifted W
and NW. Cannon shots, roaring noises, and sounds resembling blocks
rolling down the flanks were seldom reported. Based on pilot
observations, the Washington VAAC reported that an ash plume rose to
an altitude of 8.5 km (28,000 ft) a.s.l. and drifted SSE. On 4 and 8
February IG reported that ash fell in areas to the SW. Incandescence
from the crater was seen at night on 6 February.

Geologic Summary. 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 all originated from 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 temporary evacuation of the town of
Baños on the N side of the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG)
http://www.igepn.edu.ec/,
Washington Volcanic Ash Advisory Center (VAAC)
http://www.ssd.noaa.gov/VAAC/messages.html

+++++++++++++++++++++++++++++++++++++
Sally Kuhn Sennert
SI/USGS Weekly Volcanic Activity Report Editor
Global Volcanism Program
http://www.volcano.si.edu/reports/usgs/
Smithsonian Institution, National Museum of Natural History
Department of Mineral Sciences, MRC-119
Washington, D.C., 20560
Phone: 202.633.1805
Fax: 202.357.2476

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