New unrest has been noticed around 12 volcanoes, ongoing activity was reported for 4 volcanoes. This report covers active volcanoes in the world recorded from November 28 – December 4, 2012 based on Smithsonian/USGS criteria.
New activity/unrest: | Chirpoi, Kuril Islands (Russia) | Kilauea, Hawaii (USA) | Kizimen, Eastern Kamchatka (Russia) | Kliuchevskoi, Central Kamchatka (Russia) | Langila, New Britain | Lokon-Empung, Sulawesi | Paluweh, Lesser Sunda Islands (Indonesia) | Ruapehu, North Island (New Zealand) | Santa María, Guatemala | Soputan, Sulawesi | Tolbachik, Central Kamchatka (Russia) | Ulawun, New Britain
Ongoing activity: | Karymsky, Eastern Kamchatka (Russia) | Manam, Northeast of New Guinea (SW Pacific) | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia)
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 23:00 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.
CHIRPOI, Kuril Islands (Russia)
46.525°N, 150.875°E; summit elev. 742 m
SVERT reported that a thermal anomaly was detected over Snow, a volcano of Chirpoi, during 26-28 November; cloud cover prevented observations of the volcano on other days during 29 November-2 December.
Geologic summary: Chirpoi, a small island lying between the larger islands of Simushir and Urup, contains a half dozen volcanic edifices constructed within an 8-9 km wide, partially submerged caldera. The southern rim of the caldera is exposed on nearby Brat Chirpoev Island. Two volcanoes on Chirpoi Island have been historically active. The symmetrical Cherny volcano, which forms the 691 m high point of the island, erupted twice during the 18th and 19th centuries. The youngest volcano, Snow, originated between 1770 and 1810. It is composed almost entirely of lava flows, many of which have reached the sea on the southern coast. No historical eruptions are known from 742-m-high Brat Chirpoev, but its youthful morphology suggests recent strombolian activity.
KILAUEA, Hawaii (USA)
19.421°N, 155.287°W; summit elev. 1222 m
During 28 November-4 December HVO reported that on most days the circulating lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. Occasional measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas.
At Pu'u 'O'o Crater, lava circulated within the perched lava lake at the NE part of the crater, and glow emanated from spatter cones on the SE part of the crater floor and from a spatter cone at the NW edge. Lava overflowed the lava lake on 24 November and 2 December.
Lava flows remained active in two branches on the coastal plain: a small W branch, and a larger E branch with scattered activity extending from the pali to the coast E of the easternmost boundary of Hawai'i Volcanoes National Park. During 28-30 November steam plumes did not rise from the ocean entry point; on 30 November geologists confirmed that active lava flows were 100 m from the coast. Lava again entered the ocean during 1-2 and 4 December.
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.
KIZIMEN, Eastern Kamchatka (Russia)
55.130°N, 160.32°E; summit elev. 2376 m
KVERT reported that during 23-30 November moderate seismic activity at Kizimen was detected. Video and satellite images showed lava flows effusing from the summit and the E flank, summit incandescence, strong gas-and-steam activity, and hot avalanches on the S flank. A thermal anomaly was detected in satellite images during 23-26 and 29 November; cloud cover obscured views on the other days. The Aviation Color Code remained at Orange.
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.
KLIUCHEVSKOI, Central Kamchatka (Russia)
56.057°N, 160.638°E; summit elev. 4835 m
KVERT reported that during 23-30 November video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. A weak thermal anomaly was detected in satellite images during 23-26 November; cloud cover obscured views on the other days. The Aviation Color Code 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.
LANGILA, New Britain
5.525°S, 148.42°E; summit elev. 1330 m
According to the Darwin VAAC, an ash plume at an altitude of 1.5 km (5,000 ft) a.s.l. was observed by a pilot on 1 December. Ash was not detected in satellite imagery.
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.
1.358°N, 124.792°E; summit elev. 1580 m
According to the Darwin VAAC, CVGHM reported that an eruption from Lokon-Empung produced an ash plume that rose to an altitude of 4.9 km (16,000 ft) a.s.l. on 28 November. Ash was not detected in satellite imagery.
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.
PALUWEH, Lesser Sunda Islands (Indonesia)
8.32°S, 121.708°E; summit elev. 875 m
Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 28 November-4 December ash plumes from Paluweh rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted 35-65 km NW and W.
The Volcano Discovery team observed Paluweh during 30 November-2 December. They reported that a lava dome seemed to be visibly growing from all sides, with almost constant incandescent rockfalls in multiple areas. The dome was about 150 m high, the highest point on the island, and the basal diameter was 200-250 m. A vent on the upper E part of the dome ejected ash for periods of several hours and produced jet-like degassing sounds. A steam-and-ash plume rose several kilometers. Small pyroclastic flows descended the lava dome, but vegetation immediately surrounding the dome was only slightly damaged by fires caused by hot blocks and ashfall. The report also noted that local people observed the dome growing next to the Rokatenda crater in late October.
Geologic summary: Paluweh volcano, also known as Rokatenda, forms the 8-km-wide island of Paluweh N of the volcanic arc that cuts across Flores Island. Although the volcano rises about 3,000 m above the sea floor, its summit reaches only 875 m above sea level. The broad irregular summit region contains overlapping craters up to 900 m wide and several lava domes. Several flank vents occur along a NW-trending fissure. The largest historical eruption of Paluweh occurred in 1928, when a strong explosive eruption was accompanied by landslide-induced tsunamis and lava-dome emplacement.
RUAPEHU, North Island (New Zealand)
39.28°S, 175.57°E; summit elev. 2797 m
On 3 December, GeoNet reported that monitoring data suggested that Ruapehu continued in a state of unrest. Scientists aboard an overflight observed that the crater lake was quiet and that the temperature remained steady at 22 degrees Celsius. Seismicity had decreased since the early part of November. The Volcanic Alert Level remained at 1 (signs of volcano unrest) and the Aviation Colour Code remained at Yellow.
Geologic Summary. Ruapehu, one of New Zealand's most active volcanoes, is a complex stratovolcano constructed during at least four cone-building episodes. The 110 cu km volcanic massif is elongated in a NNE-SSW direction and is surrounded by another 100 cu km ring plain of volcaniclastic debris. A single historically active vent, Crater Lake, is located in the broad summit region, but at least five other vents on the summit and flanks have been active during the Holocene. Frequent mild-to-moderate explosive eruptions have occurred in historical time from the Crater Lake vent. Lahars produced by phreatic eruptions from the summit crater lake are a hazard to a ski area on the upper flanks and to river valleys below the volcano.
SANTA MARIA, Guatemala
14.756°N, 91.552°W; summit elev. 3772 m
INSIVUMEH reported in a special bulletin on 28 November that collapses of the fronts of lava flows on the flanks of Santa María's Santiaguito lava-dome complex generated pyroclastic flows and ash plumes that rose 2.4 km and drifted 30 km S, SW, and W. Activity decreased during 28-29 November. During 29-30 November block avalanches were generated from the S edge of the crater. Pyroclastic flows generated ash plumes that rose 3.2 km and drifted 10-15 km SW, WSW, and W. Rumbling sounds were reported in areas 7 km away. During 1-2 December incandescent avalanches descended the SW lava dome. During 3-4 December a new lava flow in the crater was incandescent, and produced block avalanches and ash plumes which drifted 10 km W and SW.
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.
1.108°N, 124.73°E; summit elev. 1784 m
CVGHM reported that seismicity at Soputan decreased during 1-26 November. The Alert Level was lowered to 2 (on a scale of 1-4) on 27 November.
Geologic summary: The small conical volcano of Soputan on the southern rim of the Quaternary Tondano caldera is one of Sulawesi's most active volcanoes. During historical time the locus of eruptions has included both the summit crater and Aeseput, a prominent NE-flank vent that formed in 1906 and was the source of intermittent major lava flows until 1924.
TOLBACHIK, Central Kamchatka (Russia)
55.830°N, 160.330°E; summit elev. 3682 m
KVERT reported that an eruption from Tolbachik that began on 27 November continued through 30 November. Lava effused from two fissures along the W side of Tolbachinsky Dol, a lava plateau on the SW side of the volcano, and ash plumes rose less than 500 m on 28 November. A large thermal anomaly was detected on the N part of Tolbachinsky Dol. On 29 November the Aviation Color Code was raised to Red. Ash plumes rose less than 500 m and drifted 300 km ESE. Later that day seismicity decreased and the Aviation Color Code was lowered to Orange. During 29 November-1 December Strombolian activity and lava effusion from two fissures continued. A large thermal anomaly continued to be detected in satellite imagery, and ashfall was reported in Kozyrevsk (40 km NW). According to a news article on 30 November, the lava flows destroyed two scientific base camps 10 km away. On 1 December gas-and-steam plumes with small amounts of ash rose over 400 m.
Based on information from UHPP (Yelizovo Airport), the Tokyo VAAC reported that ash plumes rose to altitudes of 4-6.1 km (13,000-20,000 ft) a.s.l. and drifted N and NW during 29-30 November and 3 December.
Geologic summary: The massive Tolbachik basaltic volcano is located at the southern end of the dominantly andesitic Kliuchevskaya volcano group. The Tolbachik massif is composed of two overlapping, but morphologically dissimilar volcanoes. The flat-topped Plosky Tolbachik shield volcano with its nested Holocene Hawaiian-type calderas up to 3 km in diameter is located east of the older and higher sharp-topped Ostry Tolbachik stratovolcano. The summit caldera at Plosky Tolbachik was formed in association with major lava effusion about 6500 years ago and simultaneously with a major southward-directed sector collapse of Ostry Tolbachik volcano. Lengthy rift zones extending NE and SSW of the volcano have erupted voluminous basaltic lava flows during the Holocene, with activity during the past two thousand years being confined to the narrow axial zone of the rifts. The 1975-76 eruption originating from the SSW-flank fissure system and the summit was the largest historical basaltic eruption in Kamchatka.
ULAWUN, New Britain
5.05°S, 151.33°E; summit elev. 2334 m
RVO reported that starting on 6 November through 30 November Ulawun produced pale grey and brown ash plumes that rose 200 m and drifted in multiple directions. Ashfall was reported on the N and NW flanks, in Voluvolu, Noau, Ubili (10 km NW), and Ulamona (10 km NW). Low rumbling was heard on 18 November.
Geologic summary: The symmetrical basaltic to andesitic Ulawun stratovolcano is the highest volcano of the Bismarck arc, and one of Papua New Guinea's most frequently active. Ulawun rises above the N coast of New Britain opposite Bamus volcano. The upper 1,000 m of the 2,334-m-high volcano is unvegetated. A steep-walled valley cuts the NW side of the volcano, and a flank lava-flow complex lies to the S of this valley. Historical eruptions date back to the beginning of the 18th century. Twentieth-century eruptions were mildly explosive until 1967, but after 1970 several larger eruptions produced lava flows and basaltic pyroclastic flows, greatly modifying the summit crater.
KARYMSKY, Eastern Kamchatka (Russia)
54.05°N, 159.45°E; summit elev. 1536 m
KVERT reported that moderate seismic activity at Karymsky was detected during 23-30 November. Satellite imagery showed a thermal anomaly on the volcano on 23 and 28 November; cloud cover obscured views on the other days. 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.
MANAM, Northeast of New Guinea (SW Pacific)
4.080°S, 145.037°E; summit elev. 1807 m
RVO reported that during 16-19 November white and blue plumes rose from Manam's Southern Crater. During 18-30 November crater incandescence and ejected incandescent tephra were observed on most nights, and a small volume of lava effused from a vent in the SE valley. During 20-30 November occasional dark gray ashplumes rose 500 m above the crater and produced ashfall in the NW and SE parts of the island. A small pyroclastic flow traveled down the SW valley on 21 November, and during 21-22 November roaring and rumbling was heard. White vapor plumes rose from Main Crater during the reporting period.
Geologic summary: The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical 1807-m-high basaltic-andesitic 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. Two summit craters are present; both are active, although most historical eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE avalanche valley. Frequent historical eruptions, typically of mild-to-moderate scale, have been recorded at Manam since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas.
31.585°N, 130.657°E; summit elev. 1117 m
JMA reported that during 26-30 November explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.8 km from the crater. Very small eruptions at Minami-dake Crater occasionally occurred. Based on information from JMA, the Tokyo VAAC reported that explosions during 29 November-4 December produced plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted W, E, SE, and S. A pilot reported that an ash plume drifted SE at an altitude of 1.8 km (6,000 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.
SHIVELUCH, Central Kamchatka (Russia)
56.653°N, 161.360°E; summit elev. 3283 m
Based on visual observations and analyses of satellite data, KVERT reported that during 23-30 November a viscous lava flow continued to effuse on the NW flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a thermal anomaly on the lava dome during 23-26 and 29 November; cloud cover obscured views on the other days. 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: Global Volcanism Program
Featured image credit: National Park Service, Photo by D.W. Peterson