VOLCANO: Smithsonian/USGS Weekly Volcanic Activity Report 13-19 July 2011

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Smithsonian/USGS Weekly Volcanic Activity Report 13-19 July 2011
From: "Kuhn, Sally" <KUHNS@xxxxxx>
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Smithsonian/USGS Weekly Volcanic Activity Report
13-19 July 2011

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


New Activity/Unrest: | Etna, Sicily (Italy) | Kaba, Sumatra (Indonesia) | Lokon-Empung, Sulawesi | Nabro, Eritrea | Puyehue-Cordón Caulle, Central Chile | Tofua, Tonga Islands

Ongoing Activity: | Fuego, Guatemala | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Kizimen, Eastern Kamchatka (Russia) | Sakura-jima, Kyushu | Santa María, Guatemala | Seulawah Agam, Sumatra (Indonesia) | Shiveluch, Central Kamchatka (Russia) | 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


ETNA Sicily (Italy) 37.734°N, 15.004°E; summit elev. 3330 m

Sezione di Catania - Osservatorio Etneo reported that on the evening of 11 July Strombolian activity began from Etna's Bocca Nuova crater, representing the first magmatic eruption since 2002. Incandescence was first recorded with a monitoring camera on the SE flank and was later visible from population centers in the SE sector of Etna. During the night of 12-13 July incandescence was more continuous and intense than during the previous night. At varying intervals, incandescent bombs that were ejected above the crater rim fell back into the crater. On 13 July volcanologists visited Bocca Nuova and observed a single large vent on the crater floor that was the source of the Strombolian activity. The strongest explosions ejected incandescent bombs several tens of meters above the crater rim. Most bombs fell back into the crater but some went over the rocky partition that divided Bocca Nuova from Voragine, and fell into the S portion of the latter.

In the evening of 15 July, volcanologists again visited Bocca Nuova and noted that the Strombolian activity had decreased slightly but within less than two hours had increased to levels greater than those observed on 13 July. Immediately to the W of the explosive vent, a lava flow was issuing from underneath a sheet of pyroclastic material deposited by the nearby Strombolian activity. The flow cascaded into a deeper depression in the W central portion of the crater floor.

On 16 July, a series of ash emissions from the pit crater located on the E flank of the SE Crater cone marked the resumption of explosive activity within the crater, and produced loud booming sounds that were widely heard in populated areas on Etna's flanks. On the evening on 18 July Strombolian activity increased and culminated into a new paroxysmal eruptive episode on 19 July. Lava flows traveled down the steep W slope of the Valle del Bove, following the same path as the lavas emitted during the preceding eruptive episodes, and stagnated at the base near Monte Centenari. Lava fountains rose 200-250 m and produced heavy fallout of fluid spatter, forming several lava flows. The largest lava flow descended the S flank of the cone reaching the base. A dense plume of gas and ash drifted E.

Geologic Summary. Mount Etna, towering above Catania, Sicily's second largest city, has one of the world's longest documented records of historical volcanism, dating back to 1500 BC. Historical lava flows cover much of the surface of this massive basaltic stratovolcano, the highest and most voluminous in Italy. Two styles of eruptive activity typically occur at Etna. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more of the three prominent summit craters, the Central Crater, NE Crater, and SE Crater. Flank eruptions, typically with higher effusion rates, occur less frequently and originate from fissures that open progressively downward from near the summit. A period of more intense intermittent explosive eruptions from Etna's summit craters began in 1995. The active volcano is monitored by the Instituto Nazionale di Geofisica e Volcanologia (INGV) in Catania.

Source: Sezione di Catania - Osservatorio Etneo http://www.ct.ingv.it/


KABA Sumatra (Indonesia) 3.52°S, 102.62°E; summit elev. 1952 m

On 14 July CVGHM reported that, since the Alert Level for Kaba was raised on 20 October 2009, seismicity had fluctuated but decreased overall. During September 2009-May 2011, when weather permitted, white plumes were seen rising 25-300 m above the crater rim, and during June-July 2011 diffuse white plumes rose 50 m above the crater rim. The Alert Level was lowered to 1 (on a scale of 1-4) on 12 July.

Geologic Summary. Kaba, a twin volcano with Mount Hitam, has an elongated summit crater complex dominated by three large historically active craters trending ENE from the summit to the upper NE flank. The SW-most crater of 1952-m-high Gunung Kaba, Kawah Lama, is the largest. Most historical eruptions have affected only the summit region of the volcano. They mostly originated from the central summit craters, although the upper-NE flank crater Kawah Vogelsang also produced explosions during the 19th and 20th centuries.

Source: Center of Volcanology and Geological Hazard Mitigation (CVGHM) http://www.vsi.esdm.go.id/


LOKON-EMPUNG Sulawesi 1.358°N, 124.792°E; summit elev. 1580 m

According to news articles, three eruptions during 14-15 July from Tompaluan crater, in the saddle between the Lokon-Empung peaks, ejected lava and ash, and caused forest fires on the W flank. A local mayor noted that 6,000 people were in shelters and one person had died from a heart attack while evacuating. Other articles stated that 5,200 people had evacuated. Explosions during 17-18 July produced ash plumes that rose 0.6-3.5 km above the crater.

Geologic Summary. The twin volcanoes Lokon and Empung, rising about 800 m above the plain of Tondano, are among the most active volcanoes of Sulawesi. Lokon, the higher of the two peaks (whose summits are only 2.2 km apart) has a flat, craterless top. The morphologically younger Empung volcano has a 400-m-wide, 150-m-deep crater that erupted last in the 18th century, but all subsequent eruptions have originated from Tompaluan, a 150 x 250 m wide double crater situated in the saddle between the two peaks. Historical eruptions have primarily produced small-to-moderate ash plumes that have occasionally damaged croplands and houses, but lava-dome growth and pyroclastic flows have also occurred.

Sources: Daily Mail http://www.dailymail.co.uk/news/article-2015099/Mount-Lokon-Race-escape-volcano-thousands-flee-mighty-Indonesia-eruption.html,
Agence France-Presse http://www.channelnewsasia.com/stories/afp_asiapacific/view/1141601/1/.html


NABRO Eritrea 13.37°N, 41.70°E; summit elev. 2218 m

Based on analyses of satellite imagery, the Toulouse VAAC reported that on 16 July an ash plume from Nabro rose to altitudes below 5.5 km (18,000 ft) a.s.l. A weak eruption detected on 17 July decreased through the day then appeared to have stopped.

Geologic Summary. The 2218-m-high Nabro stratovolcano is the highest volcano in the Danakil depression of northern Ethiopia and Eritrea. Located at the SE end of the Danakil Alps, Nabro lies in the Danakil horst. Nabro is the most prominent and NE-most of three volcanoes with large summit calderas aligned in a NE-SW direction SW of Dubbi volcano. These three volcanoes, along with Sork Ale volcano, collectively comprise the Bidu volcanic complex. The complex Nabro stratovolcano is truncated by nested calderas, 8 and 5 km in diameter. The larger caldera is widely breached to the SW. Nabro was constructed primarily of trachytic lava flows and pyroclastics. Post-caldera rhyolitic obsidian domes and basaltic lava flows were erupted inside the caldera and on its flanks. Some very recent lava flows were erupted from NNW-trending fissures transverse to the trend of the Nabro volcanic range.

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


PUYEHUE-CORDON CAULLE Central Chile 40.590°S, 72.117°W; summit elev. 2236 m

OVDAS-SERNAGEOMIN reported that on 12 and 14 July cameras installed around the Puyehue-Cordón Caulle volcanic complex recorded eruption plumes that rose no higher than 2 km above the Cordón Caulle rift zone and drifted E; weather prevented observations of the plume on 13 July. Seismic activity declined significantly. On 15 July satellite imagery showed a plume drifting 80 km E and seismic signals indicated that lava started to flow again. The effusion rate increased on 16 July, however weather again prevented observations. A light gray plume on 17 July rose 2 km above the crater and was observed in satellite imagery drifting 240 km E. According to a news article, the first plane landed at the airport in Bariloche, about 100 km E, since the airport had closed on 4 June. On 18 July a gray plume rose 5 km above the crater and drifted 150 km NW. Incandescent material observed at night was ejected 500 m above the crater and lava flows continued to be active. The Alert Level remained at Red.

Geologic Summary. The Puyehue-Cordón Caulle volcanic complex (PCCVC) is a large NW-SE-trending late-Pleistocene to Holocene basaltic-to-rhyolitic transverse volcanic chain SE of Lago Ranco. The 1799-m-high Pleistocene Cordillera Nevada caldera lies at the NW end, separated from Puyehue stratovolcano at the SE end by the Cordón Caulle fissure complex. The Pleistocene Mencheca volcano with Holocene flank cones lies NE of Puyehue. The basaltic-to-rhyolitic Puyehue volcano is the most geochemically diverse of the PCCVC. The flat-topped, 2236-m-high Puyehue volcano was constructed above a 5-km-wide caldera and is capped by a 2.4-km-wide summit caldera of Holocene age. Lava flows and domes of mostly rhyolitic composition are found on the eastern flank of Puyehue. Historical eruptions originally attributed to Puyehue, including major eruptions in 1921-22 and 1960, are now known to be from the Cordón Caulle rift zone. The Cordón Caulle geothermal area, occupying a 6 x 13 km wide volcano-tectonic depression, is the largest active geothermal area of the southern Andes volcanic zone.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN) http://www.sernageomin.cl/,
MercoPress http://en.mercopress.com/2011/07/19/first-aircraft-lands-in-bariloche-over-a-month-after-the-puyehue-volcano-eruption


TOFUA Tonga Islands 19.75°S, 175.07°W; summit elev. 515 m

Based on information from Tonga Meteorological Services and pilot observations, the Wellington VAAC reported that a cloud from Tofua rose to an altitude of 1.2 km (4,000 ft) a.s.l.

Geologic Summary. The low, forested Tofua Island in the central part of the Tonga Islands group is the emergent summit of a large stratovolcano that was seen in eruption by Captain Cook in 1774. The first Caucasian to set foot on the 515-m-high island was Capt. William Bligh in 1789, just after the renowned mutiny on the "Bounty." The volcano's summit contains a 5-km-wide caldera whose walls drop steeply about 500 m. Three post-caldera cones were constructed at the northern end of a cold fresh-water caldera lake, whose surface lies only 30 m above sea level. The easternmost cone has three craters and produced young basaltic-andesite lava flows, some of which traveled into the caldera lake. The largest and northernmost of the cones, Lofia, has a steep-sided crater that is 70 m wide and 120 m deep and has been the source of historical eruptions, first reported in the 18th century. The fumarolically active crater of Lofia has a flat floor formed by a ponded lava flow.

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


Ongoing Activity


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

INSIVUMEH reported that during 13-14 July explosions from Fuego produced ash plumes that rose 700 m above the crater and drifted W. Incandescence at night emanated from a 100-m-long lava flow on the S flank. Block avalanches reached vegetated areas.

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 (Russia) 54.05°N, 159.45°E; summit elev. 1536 m

KVERT reported that during 8-15 July moderate seismic activity continued at Karymsky and possible ash plumes rose to an altitude of 4 km (13,000 ft) a.s.l. A thermal anomaly on the volcano was detected by satellite on 8, 11, and 14 July. An ash plume observed by pilots on 12 July drifted 20 km SW. 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


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

HVO reported that two lava lakes at Kilauea were active during 13-19 July. The level of the summit lava lake fluctuated deep in the 150-m-diameter vent inset within the E wall of Halema'uma'u Crater and circulated with various patterns. Spattering occurred at locations along the edge of the lake. Periodic measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and occasionally fresh spatter nearby.

The preliminary sulfur dioxide emission rate from all of the east rift zone sources was 1,500 tonnes/day on 12 July, the highest emission rate since the end of the Kamoamoa eruption in early March. At Pu'u 'O'o, lava from vents near the NE edge and, to a lesser degree, along the W edge of the perched lava lake in the center of the crater floor continued to fill the lake. The lake level fluctuated and flowed through rim breaches, sending lava onto the Pu'u 'O'o crater floor. The near-vertical rim of the perched pond continued to be uplifted until through 17 July; the crater floor and perched lake rims formed a nearly-continuous ramp sloping away from the lake. The lava lake surface of the perched lava lake was elevated about 6 m higher than the surrounding crater floor and the rim was a few meters higher than the surface; the crater floor was 19 m below the E crater rim. Since the last measurements on 29 June, the crater floor had been uplifted about 1 m 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/


KIZIMEN Eastern Kamchatka (Russia) 55.130°N, 160.32°E; summit elev. 2376 m

KVERT reported that during 8-15 July seismicity from Kizimen was above background levels and volcanic tremor continued to be detected. Satellite images showed a bright thermal anomaly on the volcano all week. Seismic data indicated that possible ash plumes rose to an altitude of 3.3 km (10,800 ft) a.s.l. on 10 July. The Aviation Color Code remained at Orange.

Based on information from Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 19 July an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted NW.

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, has 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


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

Based on information from JMA, the Tokyo VAAC reported that during 13-19 July plumes from Sakura-jima rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. Plumes occasionally drifted W, NW, and N. On 18 July, a pilot observed an ash plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l. Explosions were reported the next day.

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


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

INSIVUMEH reported that during 13-14 July explosions from Santa María's Santiaguito lava dome complex produced ash plumes that rose 500 m above Caliente dome and drifted E. An explosion and loud rumbling was heard 10 km away. Lava flows were active on the E and SW flanks.

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/


SEULAWAH AGAM Sumatra (Indonesia) 5.448°N, 95.658°E; summit elev. 1810 m

CVGHM reported that during October 2010-July 2011 activity at Seulawah Agam decreased. Measurements indicated that seismicity decreased, water temperature decreased and pH levels were stable, gas emissions were lower, and no significant surface changes were observed. The Alert Level was lowered to 1 (on a scale of 1-4) on 11 July.

Geologic Summary. Seulawah Agam at the NW tip of Sumatra is an extensively forested volcano of Pleistocene-Holocene age constructed within the large Pleistocene Lam Teuba caldera. A smaller 8 x 6 km caldera lies within Lam Teuba caldera. The summit contains a forested, 400-m-wide crater. The active van Heutsz crater, located at 650 m on the NNE flank of Suelawah Agam, is one of several areas containing active fumarole fields. Sapper (1927) and the Catalog of Active Volcanoes of the World (CAVW) reported an explosive eruption in the early 16th century, and the CAVW also listed an eruption from the van Heutsz crater in 1839. Rock et al. (1982) found no evidence for historical eruptions. However the Volcanological Survey of Indonesia noted that although no historical eruptions have occurred from the main cone, the reported NNE-flank explosive activity may have been hydrothermal and not have involved new magmatic activity.

Source: Center of Volcanology and Geological Hazard Mitigation (CVGHM) http://www.vsi.esdm.go.id/


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

KVERT reported that seismic activity at Shiveluch was moderate during 8-15 July and indicated that possible ash plumes rose to an altitude of 5 km (16,400 ft) a.s.l. Satellite imagery showed a thermal anomaly on the lava dome during 10-11 and 14 July and a gas-and-steam plume that drifted 38 km SE on 10 July. Ground-based observers noted that ash plumes from explosions rose to an altitude of 6 km (19,700 ft) a.s.l. on 11 and 14 July. 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


SUWANOSE-JIMA Ryukyu Islands (Japan) 29.635°N, 129.716°E; summit elev. 799 m

Based on a pilot observation, the Tokyo VAAC reported that on 14 July an ash plume from Suwanose-jima rose to an altitude of 3.7 km (12,000 ft) a.s.l. Ash was not detected in satellite imagery.

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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