*******************************************************
GVP/USGS Weekly Volcanic Activity Report
10-16 January 2007
http://www.volcano.si.edu/reports/usgs/
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New Activity/Unrest: | Karthala, Comoros Islands | Soufrière Hills,
Montserrat
Ongoing Activity: | Dukono, Indonesia | Fuego, Guatemala | Karymsky,
Russia | Kilauea, USA | Langila, Papua New Guinea | Manam, Papua New
Guinea | Rabaul, Papua New Guinea | Sangay, Ecuador | Santa María,
Guatemala | Shiveluch, Russia | St. Helens, USA
New Activity/Unrest
KARTHALA Comoros Islands, Indian Ocean 11.75°N, 43.38°E; summit elev.
2,361 m
According to news articles, scientists from the Karthala Volcano
Observatory reported that an eruption occurred at Karthala during the
evening of 12 January. Residents reported incandescence at the summit
and strong fumes. Several strong tremors and earthquakes occasionally
larger than M 4 were registered on 13 January. A lava lake that formed
in the volcano's crater was seen during aerial observations on 15 January.
Geologic Summary. The southernmost and largest of the two shield
volcanoes forming Grand Comore Island (also known as Ngazidja), Karthala
contains a 3 x 4 km summit caldera generated by repeated collapse.
Elongated rift zones extend to the NNW and SE from the summit of the
Hawaiian-style shield, which has an asymmetrical profile that is steeper
to the S. Historical eruptions have modified the morphology of the
compound, irregular summit caldera. More than twenty eruptions have been
recorded since the 19th century from both summit and flank vents. Many
lava flows have reached the sea on both sides of the island, including
during many 19th-century eruptions from the summit caldera and vents on
the northern and southern flanks.
Sources: United Nations Office for the Coordination of Humanitarian
Affairs - Integrated Regional Information Networks (IRIN)
http://www.reliefweb.int/rw/RWB.NSF/db900SID/STED-6XGQ29?OpenDocument,
Reuters
http://www.sciam.com/article.cfm?chanID=sa003&articleID=ADED6EE2A29750522670AAD156B654BD
Karthala Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=0303-01=
SOUFRIÈRE HILLS Montserrat, West Indies 16.72°N, 62.18°W; summit elev.
1,052 m
During 10-16 January, lava-dome growth at Soufrière Hills continued and
was focused on the entire NW quadrant of the dome. During 10-11 January,
one pyroclastic flow was observed to the W in Gages Valley and one to
the NW in Tyres Ghaut. On 15 January, a relatively large pyroclastic
flow traveled S down the Tar River Valley and produced a cloud that
drifted W. Gas and ash venting originated from the W side of the dome
and seismicity remained at very low levels.
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 east, was formed during an eruption about 4000 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 http://www.mvo.ms/
Soufrière Hills Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=1600-05=
Ongoing Activity
DUKONO Halmahera, Indonesia 1.70°N, 127.87°E; summit elev. 1,185 m
The Darwin VAAC reported that a diffuse plume from Dukono was visible on
satellite imagery on 16 January and drifted SSE.
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 since 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
http://www.bom.gov.au/info/vaac/advisories.shtml
Dukono Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=0608-01=
FUEGO Guatemala 14.47°N, 90.88°W; summit elev. 3,763 m
INSIVUMEH reported that explosions from Fuego produced white and gray
plumes that rose to an altitude of 4 km (13,000 ft) a.s.l. and drifted
SW on 12 January. Incandescent material was propelled up to 75 m above
the summit and incandescent blocks rolled W towards the Taniluyá and
Santa Teresa ravines on 12 January and S towards the Ceniza ravine on 12
and 16 January. Based on information from the Tegucigalpa MWO and
satellite imagery, the Washington VAAC reported that a faint plume was
seen on 12 January drifting W.
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/geofisica/boletin%20formato.htm
Fuego Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=1402-09=
KARYMSKY Kamchatka Peninsula, Russia 54.05°N, 159.43°E; summit elev. 1,536 m
Activity at Karymsky continued during 5-12 January, with 100-350 shallow
earthquakes occurring daily. Ash plumes may have reached altitudes of
2.5 km (8,200 ft) a.s.l. during 7-8 January. The Level of Concern Color
Code remained at Orange <http://www.avo.alaska.edu/color_codes.php>.
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
http://www.kscnet.ru/ivs/kvert/updates.shtml
Karymsky Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=1000-13=
KILAUEA Hawaii, USA 19.43°N, 155.29°W; summit elev. 1,222 m
During 10-16 January, lava from Kilauea continued to flow from lava
deltas into the ocean at the East Lae'apuki, Kamokuna, and East
Ka'ili'ili entries. Incandescence was intermittently visible on the pali
and from the East Pond and January vents, South Wall complex, and
Drainhole vent in Pu'u 'O'o's crater. On 12 January, the summit tilt
network recorded the start of the tenth deflation-inflation (DI) event;
after 7 microradians of deflation, inflation began on 13 January. Tremor
near Pu’u ‘O’o increased and decreased in response to the DI event.
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 by
lava flows less than about 1,100 years old; 70% of the volcano's surface
is younger than 600 years. The latest Kilauea eruption began in January
1983 along the E rift zone. This long-term ongoing eruption from Pu`u
`O`o-Kupaianaha has produced lava flows that have traveled 11-12 km from
the vents to the sea, paving broad areas on the S flank of Kilauea and
adding new land beyond the former coastline.
Source: US Geological Survey Hawaiian Volcano Observatory
http://volcano.wr.usgs.gov/hvostatus.php
Kilauea information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=1302-01-
LANGILA New Britain Island, Papua New Guinea 5.53°S, 148.42°E; summit
elev. 1,330 m
During 1-15 January, eruptive activity at Langila's Crater 2 consisted
of continuous emissions of gray ash plumes that rose to altitudes of
2.3-3.3 km (7,600-10,800 ft) a.s.l. and drifted predominantly N and NE.
Fine ash fell on the flanks. Occasional roaring noises were heard
accompanying emissions. Incandescence was observed at the summit.
Geologic Summary. 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 (no.
3 crater) was formed in 1960 and has a diameter of 150 m.
Source: Herman Patia, Rabaul Volcano Observatory
Langila Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=0502-01=
MANAM offshore New Guinea, Papua New Guinea 4.10°S, 145.06°E; summit
elev. 1,807 m
RVO reported that emissions of white vapor plumes from Manam's Main
Crater were observed during 1-14 January. Brown-to-gray ash plumes
accompanied emissions on 6 and 9-11 January. Nighttime incandescence was
observed intermittently. White vapor clouds were occasionally released
from Southern Crater.
Geologic Summary. 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 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: Herman Patia, Rabaul Volcano Observatory
Manam Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=0501-02=
RABAUL New Britain Island, Papua New Guinea 4.271°S, 152.203°E; summit
elev. 688 m
RVO reported that during 4-10 January, Rabaul caldera's Tavurvur cone
emitted steam plumes with small amounts of ash that rose to 0.9-3.2 km
(3,000-10,500 ft) a.s.l. and drifted E and NE. On 10 January, a plume
rose to an altitude of 2.7 km (8,900 ft) a.s.l. and drifted NE. Roaring
noises were occasionally audible.
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: Herman Patia, Rabaul Volcano Observatory
Rabaul Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=0502-14=
SANGAY Ecuador 2.03°S, 78.34°W; summit elev. 5,188 m
Based on information from Guayaquil Meteorological Watch Office (MWO),
pilot reports, and satellite imagery, the Washington VAAC reported that
an eruption from Sangay on 14 January produced an ash plume that rose to
an altitude of 6.1 km (20,000 ft) a.s.l. and drifted SW.
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
http://www.ssd.noaa.gov/VAAC/messages.html
Sangay Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=1502-09=
SANTA MARÍA Guatemala 14.756°N, 91.552°W; summit elev. 3,772 m
INSIVUMEH reported that explosions from Santa María's Santiaguito
lava-dome complex on 12 January produced ash plumes that rose to
altitudes of 3.9-4.2 km (12,800-13,800 ft) a.s.l. Plumes drifted SW and
ashfall was reported from areas downwind. Explosions occasionally
produced incandescent blocks that rolled SW on 12 and 16 January. Based
on satellite imagery, the Washington VAAC reported that diffuse ash
plumes on 10, 12, and 14-16 January drifted SW and W. Plumes reached an
altitude of 3.7 km (12,000 ft) a.s.l. on 14 January.
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/geofisica/boletin%20formato.htm,
Washington Volcanic Ash Advisory Center
http://www.ssd.noaa.gov/VAAC/messages.html
Santa María Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=1402-03=
SHIVELUCH Kamchatka Peninsula, Russia 56.653°N, 161.360°E; summit elev.
3,283 m
Activity at Shiveluch continued above background levels during 5-12
January, with over 200 shallow earthquakes occurring daily. Based on
seismic interpretation, ash plumes rose to 7.5 km (24,600 ft) a.s.l. and
avalanches occurred throughout the reporting period. According to
observation and video data, gas-and-ash plumes rose to an altitude of 6
km (19,700 ft) a.s.l. during 5-7 and 10-11 January. Plumes drifted E and
SSW. A large thermal anomaly over the dome was noted.
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 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
http://www.kscnet.ru/ivs/kvert/updates.shtml
Shiveluch Information from the Global Volcanism Program
http://www.volcano.si.edu/gvp/world/volcano.cfm?vnum=1000-27=
ST. HELENS Washington, USA 46.20°N, 122.18°W; summit elev. 2,549 m
Data from deformation-monitoring instruments showed that during 10-16
January the lava dome at Mount St. Helens continued to grow. Seismicity
continued at low levels, punctuated by M 1.5-2.5 and occasionally larger
earthquakes.
Geologic Summary. Prior to 1980, Mount St. Helens formed a conical,
youthful volcano sometimes known as the Fuji-san of America. During the
1980 eruption the upper 400 m of the summit was removed by slope
failure, leaving a 2 x 3.5 km horseshoe-shaped crater now partially
filled by a lava dome. Mount St. Helens was formed during nine eruptive
periods beginning about 40-50,000 years ago, and has been the most
active volcano in the Cascade Range during the Holocene. The modern
edifice was constructed during the last 2,200 years, when the volcano
produced basaltic as well as andesitic and dacitic products from summit
and flank vents. Historical eruptions in the 19th century originated
from the Goat Rocks area on the N flank, and were witnessed by early
settlers.
Source: US Geological Survey Cascades Volcano Observatory
http://vulcan.wr.usgs.gov/Volcanoes/MSH/CurrentActivity/framework.html
St. Helens Information from the Global Volcanism Program
http://www.volcano.si.edu/world/volcano.cfm?vnum=1201-05-
**+++++++++++++++++++++++++++++++++++++**
*Sally Kuhn Sennert*
*Global Volcanism Program*
Smithsonian Institution
National Museum of Natural History MRC-119
Department of Mineral Sciences
Washington, D.C., 20560
http://www.volcano.si.edu/reports/usgs/index.cfm
Phone: 202.633.1805
Fax: 202.357.2476
<http://www.volcano.si.edu/reports/usgs/>++++++++++++++++++++++++++++++++++++++++++
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