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SI/USGS Weekly Volcanic Activity Report 8-14 September 2010
From: "Kuhn, Sally" <KUHNS@xxxxxx>
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SI/USGS Weekly Volcanic Activity Report
8-14 September 2010
Sally Kuhn Sennert - Weekly Report Editor
kuhns@xxxxxx
URL: http://www.volcano.si.edu/reports/usgs/
New Activity/Unrest: | Cleveland, Chuginadak Island | Ekarma, Kuril Islands (Russia) | Kliuchevskoi, Central Kamchatka (Russia) | Nevado del Huila, Colombia | Planchón-Peteroa, Central Chile-Argentina border | Santa María, Guatemala | Sinabung, Sumatra (Indonesia)
Ongoing Activity: | Arenal, Costa Rica | Batu Tara, Komba Island (Indonesia) | Dukono, Halmahera | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Reventador, Ecuador | Sakura-jima, Kyushu | Sangay, Ecuador | 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
CLEVELAND Chuginadak Island 52.825°N, 169.944°W; summit elev. 1730 m
AVO reported that during 7-8 September clear-weather satellite views of Cleveland showed no thermal anomalies or recent deposits on the flanks. The Volcano Alert Level and the Aviation Color Code were lowered to Unassigned. On 11 September, a thermal anomaly was observed in satellite imagery. The next day a possible ash plume seen in satellite imagery rose to the estimated altitude of 7.6 km (25,000 ft) a.s.l. and drifted E. The Volcano Alert Level and the Aviation Color Code were again raised to Advisory and Yellow, respectively. A thermal anomaly was again visible during 13-14 September.
Geologic Summary. 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 (AVO) http://www.avo.alaska.edu/
EKARMA Kuril Islands (Russia) 48.958°N, 153.93°E; summit elev. 1170 m
On 13 September, SVERT reported that strong steam-and-gas activity from Ekarma continued. Ekarma does not have a seismic network; satellite image analysis and infrequent ground observations are the primary tool for monitoring many of the Kuril Islands volcanoes.
Geologic Summary. The small 5 x 7.5 km island of Ekarma lies 8.5 km north of Shiashkotan Island along an E-W-trending volcanic chain extending westward from the central part of the main Kuril Island arc. Ekarma is composed of two overlapping basaltic-andesite to andesitic volcanoes, the western of which has been historically active. Lava flows radiate 3 km in all directions from the summit of the younger cone to the sea, forming a lobate shoreline. A lava dome that was emplaced during the first historical eruption, in 1776-79, forms the peaked, 1170-m-high summit of the island. The only other historical eruption produced minor explosions in 1980.
Source: Sakhalin Volcanic Eruption Response Team (SVERT) http://www.imgg.ru/rus/labs_vulcan_hazard.php
KLIUCHEVSKOI Central Kamchatka (Russia) 56.057°N, 160.638°E; summit elev. 4835 m
KVERT reported that during 3-10 September seismic activity from Kliuchevskoi was above background levels and lava flowed down the SW and NW flanks. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano. During 2-4 September ash plumes seen in satellite imagery drifted 150 km S and SW at an altitude of 6.5 km (21,300 ft) a.s.l. Phreatic bursts on the SW flank were observed on 5 September and Strombolian activity was seen during 5-7 September. Seismic data suggested that during 5-6 September ash plumes rose to an altitude of 6 km (19,700 ft) a.s.l.
Based on analyses of satellite imagery, the Tokyo VAAC reported that a possible eruption on 12 September produced a plume that rose to an altitude of 7.6 km (25,000 ft) a.s.l. and drifted SE. On 13 September an ash plume rose to an altitude of 9.8 km (32,000 ft) a.s.l. and drifted NE according to information sent from the Yelizovo Airport (UHPP). Ash was seen in subsequent satellite images during 13-14 September. The Aviation Color Code level remained at Orange.
Geologic Summary. 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.
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
NEVADO DEL HUILA Colombia 2.93°N, 76.03°W; summit elev. 5364 m
The Popayán Volcano Observatory (INGEOMINAS) reported increased activity from Nevado del Huila on 8 and 9 September. Pulses of tremor were associated with periodic emissions of gas, ash, and incandescent material observed with the Tafxnú and Maravillas web cameras. During 8-14 September plumes of steam and occasionally ash rose as high as 2 km above the summit. The Alert Level was raised to II (Orange; "probable eruption in term of days or weeks").
Geologic Summary. Nevado del Huila, the highest active volcano in Colombia, is an elongated N-S-trending volcanic chain mantled by a glacier icecap. The andesitic-dacitic volcano was constructed within a 10-km-wide caldera. Volcanism at Nevado del Huila has produced six volcanic cones whose ages in general migrated from south to north. Two glacier-free lava domes lie at the southern end of the Huila volcanic complex. The first historical eruption from this little known volcano took place in the 16th century. Two persistent steam columns rise from the central peak, and hot springs are also present.
Source: Instituto Colombiano de Geología y Minería (INGEOMINAS) http://www.ingeominas.gov.co//
PLANCHON-PETEROA Central Chile-Argentina border 35.240°S, 70.570°W; summit elev. 4107 m
SERNAGEOMIN reported that an overflight of Planchón-Peteroa on 7 September revealed that the explosions the day before were possibly phreato-magmatic in origin and similar to the explosions in 1991. Pulses of gas and ash had occurred every 40-60 seconds during the eruption. Plumes rose 200 m above the crater and ash mostly fell within 10 km to the E. During 10-13 September, plumes rising from the vent had progressively less ash and higher concentrations of water vapor. On 13 September, SERNAGEOMIN reported that petrographic and mineralogical studies of the ash indicated no juvenile components. The Alert Level remained at 4, Yellow.
Geologic Summary. Planchón-Peteroa is an elongated complex volcano along the Chile-Argentina border with several overlapping calderas. Activity began in the Pleistocene with construction of the basaltic-andesite to dacitic Volcán Azufre, followed by formation of basaltic and basaltic-andesite Volcán Planchón, 6 km to the N. About 11,500 years ago, much of Azufre and part of Planchón collapsed, forming the massive Río Teno debris avalanche, which reached Chile's Central Valley. Subsequently, Volcán Planchón II was formed. The youngest volcano, andesitic and basaltic-andesite Volcá Peteroa, consists of scattered vents between Azufre and Planchón. Peteroa has been active into historical time and contains a small steaming crater lake. Historical eruptions from the Planchón-Peteroa complex have been dominantly explosive, although lava flows were erupted in 1837 and 1937.
Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN) http://www.sernageomin.cl/
SANTA MARIA Guatemala 14.756°N, 91.552°W; summit elev. 3772 m
INSIVUMEH reported that an eruption from Santa María's Santiaguito lava dome complex on 11 September generated two pyroclastic flows that traveled 3 km SW and deposited material in the Nimá II drainage. Ash plumes rose 1 km above the crater and drifted E and SE. On 13 September white plumes rose 100 m and drifted S.
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.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) http://www.insivumeh.gob.gt/
SINABUNG Sumatra (Indonesia) 3.17°N, 98.392°E; summit elev. 2460 m
CVGHM reported that during 8-11 September Sinabung emitted white-to-gray plumes that rose 30-100 m above the crater and generally drifted E. Deformation measurements during 8-14 September showed a slow rate of inflation. Based on analyses of satellite imagery and the CVGHM web camera, the Darwin VAAC reported that on 12 and 14 September ash plumes rose to altitudes of 4.3-4.6 km (14,000-15,000 ft) a.s.l. The Alert Level remained at 4 (on a scale of 1-4).
Geologic Summary. Gunung Sinabung is a Pleistocene-to-Holocene stratovolcano with many lava flows on its flanks. The migration of summit vents along a N-S line gives the summit crater complex an elongated form. The youngest crater of this conical, 2460-m-high andesitic-to-dacitic volcano is at the southern end of the four overlapping summit craters. An unconfirmed eruption was noted in 1881, and solfataric activity was seen at the summit and upper flanks of Sinabung in 1912, although no confirmed historical eruptions were recorded prior to 2010.
Sources: Center of Volcanology and Geological Hazard Mitigation (CVGHM) http://portal.vsi.esdm.go.id/joomla/,
Darwin Volcanic Ash Advisory Centre (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/AU/messages.html
Ongoing Activity
ARENAL Costa Rica 10.463°N, 84.703°W; summit elev. 1670 m
OVSICORI-UNA reported that during August activity originating from Arenal's Crater C consisted of gas emissions, sporadic Strombolian eruptions, and occasional avalanches. Some of the Strombolian eruptions caused glass to vibrate in buildings located 6.5 km NE. Block avalanches descended the N and NE flanks. Acid rain and small amounts of ejected pyroclastic material affected the NE, E, and SE flanks. Crater D produced only fumarolic activity.
Geologic Summary. Conical Volcan Arenal is the youngest stratovolcano in Costa Rica and one of its most active. The 1,657-m-high andesitic volcano towers above the eastern shores of Lake Arenal, which has been enlarged by a hydroelectric project. The earliest known eruptions of Arenal took place about 7,000 years ago. Growth of Arenal has been characterized by periodic major explosive eruptions at several-hundred-year intervals and periods of lava effusion that armor the cone. Arenal's most recent eruptive period began with a major explosive eruption in 1968. Continuous explosive activity accompanied by slow lava effusion and the occasional emission of pyroclastic flows has occurred since then from vents at the summit and on the upper western flank.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) http://www.ovsicori.una.ac.cr/
BATU TARA Komba Island (Indonesia) 7.792°S, 123.579°E; summit elev. 748 m
Based on analyses of satellite imagery, the Darwin VAAC reported that on 8 September an ash plume from Batu Tara rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 55 km NW.
Geologic Summary. The small isolated island of Batu Tara in the Flores Sea about 50 km north of Lembata (formerly Lomblen) Island contains a scarp on the eastern side similar to the Sciara del Fuoco of Italy's Stromboli volcano. Vegetation covers the flanks of Batu Tara to within 50 m of the 748-m-high summit. Batu Tara lies north of the main volcanic arc and is noted for its potassic leucite-bearing basanitic and tephritic rocks. The first historical eruption from Batu Tara, during 1847-52, produced explosions and a lava flow.
Source: Darwin Volcanic Ash Advisory Centre (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/AU/messages.html
DUKONO Halmahera 1.68°N, 127.88°E; summit elev. 1335 m
Based on analyses of satellite imagery, the Darwin VAAC reported that during 8-11 and 14 September ash plumes from Dukono rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 35-95 km SW, W, and NW.
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
KARYMSKY Eastern Kamchatka (Russia) 54.05°N, 159.45°E; summit elev. 1536 m
KVERT reported that during 3-10 September seismic activity from Karymsky was above background levels and suggested that possible ash plumes rose to an altitude of 3.2 km (10,500 ft) a.s.l. Satellite imagery showed a thermal anomaly over the volcano during the week. The Aviation Color Code level 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
During 8-14 September HVO reported that activity at Kilauea continued from the summit caldera and the east rift zone. At the summit caldera, the level of the lava-pool surface in the deep pit within the floor of Halema'uma'u crater remained mostly stable; glow from the vent was also visible at night. A plume from the vent drifted SW and deposited ash, and occasionally Pele's hair and spatter, nearby. At Pu'u 'O'o crater, incandescence emanated from a lava flow on the SW floor on most nights. During an overflight on 9 September, geologists saw that the lava flow had ponded on the W side of the crater floor. At the east rift zone, lava that flowed through the TEB lava-tube system mainly fed the Puhi-o-Kalaikini ocean entry.
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/
REVENTADOR Ecuador 0.077°S, 77.656°W; summit elev. 3562 m
The Washington VAAC reported that on 9 September an ash plume from Reventador at an altitude of 5.5 km (18,000 ft) a.s.l. was observed by a pilot.
Geologic Summary. Reventador is the most frequently active of a chain of Ecuadorian volcanoes in the Cordillera Real, well E of the principal volcanic axis. It is a forested stratovolcano that rises above the remote jungles of the western Amazon basin. A 3-km-wide caldera breached to the E was formed by edifice collapse and is partially filled by a young, unvegetated stratovolcano that rises about 1,300 m above the caldera floor. Reventador has been the source of numerous lava flows as well as explosive eruptions that were visible from Quito in historical time. Frequent lahars in this region of heavy rainfall have constructed a debris plain on the eastern floor of the caldera.
Source: 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 explosions from Sakura-jima on 8 and 10 September produced plumes that rose to altitudes of 1.5-1.8 km (6,000-8,000 ft) a.s.l. Some of the plumes drifted E and NE. On 9 September a pilot reported that an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l.
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
SANGAY Ecuador 2.002°S, 78.341°W; summit elev. 5230 m
The Washington VAAC reported that on 10 September a small plume and a thermal anomaly from Sangay were seen in satellite imagery. Based on information from Tegucigalpa MWO, pilot observations, and analyses of satellite imagery, the VAAC reported that on 13 September small plumes of gas with possible ash drifted SW. A thermal anomaly had also been detected for the previous few hours.
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
SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m
KVERT reported that during 3-10 September seismic activity from Shiveluch was above background levels and suggested that possible ash plumes rose to an altitude of 6.5 km (21,300 ft) a.s.l. during 3-4 September. Gas-and-ash plumes were observed on 6 and 7 September; clouds prevented observations on the other days. Satellite imagery analysis showed a thermal anomaly on the volcano during the week. The Aviation Color Code level 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 several small-to-moderate sized pyroclastic flows from Soufrière Hills during 3-10 September removed parts of the cold dome carapace, resulting in the thermal camera displaying several hotter regions on the lava dome. The largest pyroclastic flow traveled 2.5 km down the Gages valley to the W on 9 September. 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 capital 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 11 September. Details of possible resulting plumes 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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