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Smithsonian/USGS Weekly Volcanic Activity Report 2-8 March 2011
From: "Kuhn, Sally" <KUHNS@si.edu>
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Smithsonian/USGS Weekly Volcanic Activity Report
2-8 March 2011
Sally Kuhn Sennert - Weekly Report Editor
kuhns@si.edu
URL: http://www.volcano.si.edu/reports/usgs/
New Activity/Unrest: | Kilauea, Hawaii (USA) | Santa María, Guatemala
Ongoing Activity: | Bulusan, Luzon | Karymsky, Eastern Kamchatka (Russia) | Kirishima, Kyushu | Kizimen, Eastern Kamchatka (Russia) | Merapi, Central Java (Indonesia) | Popocatépetl, México | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) | Soufrière Hills, Montserrat | Suwanose-jima, Ryukyu Islands (Japan)
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
KILAUEA Hawaii (USA) 19.421°N, 155.287°W; summit elev. 1222 m
During 1-4 March, activity from Kilauea's summit caldera and east rift zone was similar to activity during the previous several weeks. The level of the circulating lava-pool surface in the deep pit within Halema'uma'u crater fluctuated and rose to at most 70 below the crater floor. Scattered surface flows were active on the pali and coastal plain, and lava covered large portions of Pu'u 'O'o's crater floor. An unusually high number of earthquakes were located at Kilauea; during 1-4 March a majority of the earthquakes were located at the upper east rift zone.
On 5 March at 1342 there was the onset of rapid deflation at Pu'u 'O'o and increased tremor along Kilauea's middle east rift zone, and at 1400 the summit began to deflate. Between 1416 and 1421 the floor of the Pu'u 'O'o crater began to collapse and within 10 minutes incandescent ring fractures opened on the crater floor. As the floor continued to drop, lava appeared in the center and the NE spatter cone collapsed. The collapse of a large block along the E crater wall produced an ash plume. The floor continued to drop as fume obscured the camera view at 1626. The Aviation Color Code was raised to Red and the Volcano Alert Level was raised to Warning. A later report indicated that the crater floor dropped a minimum of 115 m.
Coincident with the Pu'u 'O'o collapse, an earthquake swarm began along the east rift zone in the area of Maka'opuhi and Napau craters, WSW of Pu'u 'O'o. A fissure, ultimately 2.3 km long, opened along the east rift zone between Napau Crater and Pu'u 'O'o, erupting spatter up to 25 m high and lava that burned nearby vegetation. Lava on one side of the fissure flowed into a nearby deep parallel fissure and disappeared. Fissure activity had paused by 2155.
Kilauea's summit continued to deflate and the lava lake level within the Halema'uma'u crater vent dropped, facilitating rockfalls from the vent wall. On 6 March at 0703 the lake level to receded almost beyond the webcam view following a large collapse. Spattering from the fissure resumed and two more fissures opened that produced more gas than lava. Spatter was reaching heights of 40 m. The tiltmeter on the N flank of Pu'u 'O'o recorded over 150 microradians of deflation beginning at 1400 on 5 March that markedly slowed by the morning of 6 March. Rockfalls exposed incandescent areas within Pu'u 'O'o. Lava flows on the coastal plain and pali were less active. The average sulfur dioxide emission rate from all east rift zone sources was 10,000 tonnes/day on 6 March, 2011, the highest rate there since an eruptive surge in July 2008 produced an emission rate of 7,000 tonnes/day.
On 7 March the Aviation Color Code was lowered to Orange. Vigorous spattering from the W end of the fissure continued; spatter rose as high as 30 m. No active lava flows were observed on the pali or coastal plain. The lava lake surface in Halema'uma'u crater was 200 m below the crater floor, based on visual estimates. Rockfalls in the crater produced dusty-brown plumes during 7-8 March. Low fountains and spattering from the fissure fed several lava flows that advanced S.
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/
SANTA MARIA Guatemala 14.756°N, 91.552°W; summit elev. 3772 m
INSIVUMEH reported that during 2-3 March explosions from Santa María's Santiaguito lava dome complex produced ash plumes that rose 800 m above Caliente dome and drifted SW. Avalanches traveled S, SE, and SW, and ashfall was reported in Monte Claro, Patzulín, La Florida, and El Faro on the S and SE flanks. Two pyroclastic flows were also detected. On 3 March an explosion produced an ash plume that rose 800 m above Caliente dome and drifted W and SW. Ashfall was reported in multiple areas downwind. The explosion was accompanied by a pyroclastic flow that traveled 2.5 km down Rio Nima I on the SE flank. A few explosions occurred during 3-4 March; ash plumes rose 900 m above Caliente dome. Ash fell in La Florida, El Faro, and Palajunoj (SW flank). Based on analyses of satellite imagery, the Washington VAAC reported that ash was detected on 6 March. The next day an ash plume drifted almost 20 km SW.
During 7-8 March the seismic network detected explosions, avalanches, and pyroclastic flows. At least eight pyroclastic flows descended the E flank and deposited material in Rio Nima II. Ash plumes rose 1 km and drifted S and SW causing ashfall 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
Ongoing Activity
BULUSAN Luzon 12.770°N, 124.05°E; summit elev. 1565 m
During 2-8 March, PHIVOLCS reported that up to four daily volcanic earthquakes at Bulusan were detected by the seismic network. Although cloud cover mostly prevented observations of the summit area, steam was observed rising from thermal vents during 2-4 and 7-8 March. Based on notices from the Manila airport (RPLL) and satellite image observations, the Tokyo VAAC reported that during 3-4 March ash was observed.
Geologic Summary. Luzon's southernmost volcano, Bulusan, was constructed within the 11-km-diameter dacitic Irosin caldera, which was formed more than 36,000 years ago. A broad, flat moat is located below the prominent SW caldera rim; the NE rim is buried by the andesitic Bulusan complex. Bulusan is flanked by several other large intracaldera lava domes and cones, including the prominent Mount Jormajan lava dome on the SW flank and Sharp Peak to the NE. The summit of Bulusan volcano is unvegetated and contains a 300-m-wide, 50-m-deep crater. Three small craters are located on the SE flank. Many moderate explosive eruptions have been recorded at Bulusan since the mid-19th century.
Sources: Philippine Institute of Volcanology and Seismology (PHIVOLCS) http://www.phivolcs.dost.gov.ph/,
Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
KARYMSKY Eastern Kamchatka (Russia) 54.05°N, 159.45°E; summit elev. 1536 m
KVERT reported that moderate seismic activity was detected at Karymsky during 25 February-4 March. Seismic data indicated that possible ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. Satellite imagery showed a thermal anomaly over the volcano on 25 February and 2 March. The Aviation 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
KIRISHIMA Kyushu 31.931°N, 130.864°E; summit elev. 1700 m
The Tokyo VAAC reported that an ash plume from Kirishima's Shinmoe-dake (Shinmoe peak) observed by a pilot on 3 March rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted NE. Based on reports from JMA, the Tokyo VAAC reported that plumes rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted SE during 3-4 and 8 March.
Geologic Summary. Kirishima is a large group of more than 20 Quaternary volcanoes located north of Kagoshima Bay. The late-Pleistocene to Holocene volcano group consists of stratovolcanoes, pyroclastic cones, maars, and underlying shield volcanoes located over an area of 20 x 30 km. The larger stratovolcanoes are scattered throughout the field, with the centrally located, 1,700-m-high Karakuni-dake being the highest. Onami-ike and Mi-ike, the two largest maars, are located SW of Karakuni-dake and at its far eastern end, respectively. Holocene eruptions have been concentrated along an E-W line of vents from Mi-ike to Ohachi, and at Shinmoe-dake to the NE. Frequent small-to-moderate explosive eruptions have been recorded since the 8th century.
Source: Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
KIZIMEN Eastern Kamchatka (Russia) 55.130°N, 160.32°E; summit elev. 2376 m
KVERT reported that during 25 February-4 March seismicity from Kizimen was high but variable, and many shallow volcanic earthquakes as well as volcanic tremor continued to be detected. Satellite images showed a bright thermal anomaly over the volcano daily. Ash plumes drifted 180 km N on 25 and 28 February, and 2 March. The Aviation Color Code remained at Orange.
Based on information from KEMSD and analyses of satellite imagery, the Tokyo VAAC reported that on 5 March eruptions produced plumes that rose to altitudes of 6.1-6.4 km (20,000-21,000 ft) a.s.l.
Geologic Summary. Kizimen is an isolated, conical stratovolcano that is morphologically similar to Mount St. Helens prior to its 1980 eruption. The summit of Kizimen consists of overlapping lava domes, and blocky lava flows descend the flanks of the volcano, which is the westernmost of a volcanic chain north of Kronotsky volcano. The 2,376-m-high Kizimen was formed during four eruptive cycles beginning about 12,000 years ago and lasting 2,000-3,500 years. The largest eruptions took place about 10,000 and 8300-8400 years ago, and three periods of longterm lava-dome growth have occurred. The latest eruptive cycle began about 3,000 years ago with a large explosion and was followed by lava-dome growth lasting intermittently about 1,000 years. An explosive eruption about 1,100 years ago produced a lateral blast and created a 1.0 x 0.7 km wide crater breached to the NE, inside which a small lava dome (the fourth at Kizimen) has grown. A single explosive eruption, during 1927-28, ha
s been recorded in historical time.
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
MERAPI Central Java (Indonesia) 7.542°S, 110.442°E; summit elev. 2968 m
CVGHM reported that gas plumes rose from Merapi during 28 February-6 March. The highest plume which rose 100 m and drifted E was observed on 5 March from the Babadan post on the NW flank. The number of multi-phase (MP) earthquakes was slightly lower compared to the previous week. The Alert Level remained at 2 (on a scale of 1-4).
Geologic Summary. 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).
Source: Center of Volcanology and Geological Hazard Mitigation (CVGHM) http://www.vsi.esdm.go.id/
POPOCATEPETL México 19.023°N, 98.622°W; summit elev. 5426 m
CENAPRED reported that during 2-4 and 6 March steam-and-gas emissions from Popocatépetl occasionally contained small amounts of ash. The Washington VAAC noted that a gas-and-ash plume drifting 130 km SE at an altitude of 9.1 km (30,000 ft) a.s.l. on 3 March.
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.
Sources: Centro Nacional de Prevencion de Desastres (CENAPRED) http://www.cenapred.unam.mx/es/,
Washington Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/messages.html
SAKURA-JIMA Kyushu 31.585°N, 130.657°E; summit elev. 1117 m
Based on information from JMA, the Tokyo VAAC reported that during 2-5 and 8 March explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-1.8 km (4,000-6,000 ft) a.s.l. and drifted E, SE, and S. During 2-4 and 5 March, pilots reported that ash plumes rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. Some plumes drifted N and 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.
Source: Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m
KVERT reported that moderate seismic activity was detected at Shiveluch during 25 February-4 March. Gas-and-steam activity was observed during 24-25 February; cloud cover prevented observations on the other days. A thermal anomaly over the lava dome was observed in satellite imagery during 25-26 February, and 2 March. Ash plumes drifted over 140 km N during 26-27 February. The Aviation Color Code remained at Orange.
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. Intermittent explosive eruptions began in the 1990s 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 (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php
SOUFRIERE HILLS Montserrat 16.72°N, 62.18°W; summit elev. 915 m
MVO reported that during 25 February-4 March activity at the Soufrière Hills lava dome was at a low level. Clear views from a helicopter on 3 March revealed modest changes in the lava dome; continued degradation of the W face was evident and the E face showed undercutting with overhanging areas. Small areas of incandescence were visible on the N face of the dome during clear evenings. The Hazard Level remained at 3.
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 ca
pital city of Plymouth, causing major social and economic disruption.
Source: Montserrat Volcano Observatory (MVO) http://www.mvo.ms/
SUWANOSE-JIMA Ryukyu Islands (Japan) 29.635°N, 129.716°E; summit elev. 799 m
Based on information from JMA, the Tokyo VAAC reported an explosion from Suwanose-jima on 3 March. Details of a possible resulting plume were not reported.
Geologic Summary. The 8-km-long, spindle-shaped island of Suwanose-jima in the northern Ryukyu Islands consists of an andesitic 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 east 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, 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: Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
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