New unrest has been noticed around 6 volcanoes, ongoing activity was reported for 7 volcanoes. This report covers active volcanoes in the world recorded from January 16 – January 22, 2013 based on Smithsonian/USGS criteria.
New activity/unrest: | Copahue, Central Chile-Argentina border | Ketoi, Kuril Islands (Russia) | Kizimen, Eastern Kamchatka (Russia) | Rabaul, New Britain | Reventador, Ecuador | White Island, New Zealand
Ongoing activity: | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Lokon-Empung, Sulawesi | Nevado del Ruiz, Colombia | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) |Tolbachik, 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 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.
COPAHUE, Central Chile-Argentina border
37.85°S, 71.17°W; summit elev. 2997 m
OVDAS-SERNAGEOMIN reported that the web camera near Copahue recorded white gas plumes rising 250-1,300 m above the crater during 15-18 January and drifting W and NW. Seismicity remained at low levels. The Alert Level was lowered from Orange to Yellow on 18 January.
A seismic swarm of long-period earthquakes started at 1420 on 22 January. The earthquakes were initially deep but became shallower, and volcano-tectonic events were more frequently detected, until the next report posted at 2200. Web camera and satellite images did not show any changes. The Alert Level was raised to Orange.
Geologic summary: Volcán Copahue is an elongated composite cone constructed along the Chile-Argentina border within the 6.5 x 8.5 km wide Trapa-Trapa caldera that formed between 0.6 and 0.4 million years ago near the NW margin of the 20 x 15 km Pliocene Caviahue (Del Agrio) caldera. The eastern summit crater, part of a 2-km-long, ENE-WSW line of nine craters, contains a briny, acidic 300-m-wide crater lake (also referred to as El Agrio or Del Agrio) and displays intense fumarolic activity. Acidic hot springs occur below the eastern outlet of the crater lake, contributing to the acidity of the Río Agrio, and another geothermal zone is located within Caviahue caldera about 7 km NE of the summit. Infrequent mild-to-moderate explosive eruptions have been recorded at Copahue since the 18th century. Twentieth-century eruptions from the crater lake have ejected pyroclastic rocks and chilled liquid sulfur fragments.
KETOI, Kuril Islands (Russia)
47.35°N, 152.475°E; summit elev. 1172 m
SVERT reported that gas-and-steam emissions from Ketoi's Pallas Peak were observed in satellite imagery during 16-17 January.
Geologic summary: The circular, 10-km-wide Ketoi island, which rises across the 19-km-wide Diana Strait from Simushir Island, hosts of one of the most complex volcanic structures of the Kuril Islands. The rim of a 5-km-widePleistocene caldera is exposed only on the NE side. A younger 1172-m-high stratovolcano forming the NW part of the island is cut by a horst-and-graben structure containing two solfatara fields. A 1.5-km-wide freshwater lake fills an explosion crater in the center of the island. Pallas Peak, a large andesitic cone in the NE part of the caldera, is truncated by a 550-m-wide crater containing a brilliantly colored turquoise crater lake. Lava flows from Pallas Peak overtop the caldera rim and descend nearly 5 km to the SE coast. The first historical eruption of Pallas Peak, during 1843-46, was its largest.
KIZIMEN, Eastern Kamchatka (Russia)
55.130°N, 160.32°E; summit elev. 2376 m
KVERT reported that during 11-18 January moderate seismic activity continued at Kizimen. Video data showed that lava continued to extrude from the summit onto the E flank. Summit incandescence, strong gas-and-steam activity, and occasional hot avalanches on the W and E flanks accompanied the process. Satellite images detected two new lava flows on the SE flank and a thermal anomaly over the volcano during 10-15 January. 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.
RABAUL, New Britain
4.271°S, 152.203°E; summit elev. 688 m
RVO reported that roaring and rumbling noises from Rabaul caldera's Tavurvur cone began at 2128 on 19 January and lasted for about 15 minutes. Darkness prevented visual observations but the next day ash emissions were evident. On 20 January small discrete explosions generated ash clouds that rose up to 500 m above the crater and drifted E and SE. A few days before the eruption an observer noticed that vegetation on the N flanks of South Daughter (Turangunan, ~2 km to the E) had browned, and on 18 January a climber reported a strong sulfur dioxide odor.
A loud explosion at 2325 on 20 January was followed by a few minutes of continuous roaring and rumbling. During 20-22 January light gray ash emissions occurred at irregular intervals; the color of the plumes suggested mostly water vapor with low ash content. Plumes rose 200 m and drifted ESE on 20 January, and SW, S, and SSE on 21 January. Activity increased during 21-22 January with more frequent ash emissions occurring for extended periods. According to a news article, flights to Tokua airport were cancelled on 21 January.
Emissions subsided in the afternoon of 22 January but small-to-moderate explosions continued. A large explosion at 2147 ejected incandescent fragments, and produced an ash plume that rose 2 km and drifted SE and ESE. Explosions were heard through the night. Ash plumes that rose from the crater on 23 January drifted SE.
Geologic summary: The low-lying Rabaul caldera on the tip of the Gazelle Peninsula at the NE end of New Britain forms a broad sheltered harbor. The outer flanks of the 688-m-high asymmetrical pyroclastic shield volcano are formed by thick pyroclastic-flow deposits. The 8 x 14 km caldera is widely breached on the E, where its floor is flooded by Blanche Bay. Two major Holocene caldera-forming eruptions at Rabaul took place as recently as 3,500 and 1,400 years ago. Three small stratovolcanoes lie outside the northern and NE caldera rims. Post-caldera eruptions built basaltic-to-dacitic pyroclastic cones on the caldera floor near the NE and western caldera walls. Several of these, including Vulcan cone, which was formed during a large eruption in 1878, have produced major explosive activity during historical time. A powerful explosive eruption in 1994 occurred simultaneously from Vulcan and Tavurvur volcanoes and forced the temporary abandonment of Rabaul city.
0.077°S, 77.656°W; summit elev. 3562 m
IG reported that during 16-21 January seismicity at Reventador was moderate; cloud cover prevented visual observations. Incandescence in the crater was observed at night during 21-22 January. Starting at 0900 on 22 January seismicity at Reventador increased and was characterized by constant low-frequency, high-energy tremor detected by seismic stations around the volcano. Observers reported lava fountains in the crater and lava flows on the flanks, both of which became more intense at 1800. Explosions produced white-to-light-gray plumes that rose 2 km and drifted W.
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.
WHITE ISLAND, New Zealand
37.52°S, 177.18°E; summit elev. 321 m
On 22 January GeoNet Data Centre reported that unrest at White Island continued. A volcanologist visiting the area on 21 January observed that hydrothermal activity in the small "hot lake" had increased. The lake surface "domed up" from rising steam and gas, that also brought large amounts of sediment to the surface, often with a vivid white steam-and-gas "flashing" from around the base. Stronger events periodically occurred. The report noted that the activity had been increasing since late 2012 and was now semi-continuous. The Aviation Colour Code remained at Yellow (second lowest on a four-color scale) and the Volcanic Alert Level remained at 1.
Geologic summary: The uninhabited 2 x 2.4 km White Island, one of New Zealand's most active volcanoes, is the emergent summit of a 16 x 18 km submarine volcano in the Bay of Plenty about 50 km offshore of North Island. The 321-m-high island consists of two overlapping stratovolcanoes; the summit crater appears to be breached to the SE because the shoreline corresponds to the level of several notches in the SE crater wall. Throughout the shorthistorical period beginning in 1826 the volcano has had long periods of continuous hydrothermal activity and steam release, punctuated by small-to-medium eruptions. Its activity also forms a prominent part of Maori legends. The most recent eruptive episode, which began on 7 March 2000, included the largest eruption at White Island in the past 20 years on 27 July.
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 11-18 January, indicating that possible ash plumes rose to an altitude of 2.5 km (8,200 ft) a.s.l. Satellite imagery showed a thermal anomaly on the volcano on 11 and 14 January; cloud cover prevented observations on the other days. The Aviation Color Coderemained at Orange.
Geologic summary: Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetricalstratovolcano 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.
KILAUEA, Hawaii (USA)
19.421°N, 155.287°W; summit elev. 1222 m
During 16-22 January HVO reported that the circulating lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. The gas plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. During 15-16 January rocks fell into and disrupted the lake surface. The lake level was 35 m below the Halema'uma'u crater floor on 16 January and 27 m below the floor on 19 January.
At Pu'u 'O'o Crater, glow emanated from spatter cones on the SE part of the crater floor, from a spatter cone at the NW edge of the floor, and from a circulating lava lake on the NE part of the floor. Lava flows were active in a 1-km-wide area that stretched from near the base of the pali to the coast. Web cameras recorded steam plumes from lava sporadically entering the ocean at multiple locations. Lava levels remained mostly high in the crater; several lava flows from multiple vents were active on the crater floor. The lava lake was perched several meters above the crater rim and sporadically issued lava that flowed outside the crater and onto the E flank of the cone.
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.
1.358°N, 124.792°E; summit elev. 1580 m
Based on reports from CVGHM and ASHTAMs (a special NOTAM for volcanic ash), the Darwin VAAC reported that ash plumes rose from Lokon-Empung rose to altitudes of 3.7-4.5 km (12,000-14,800 ft) a.s.l. during 15-16 January. 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-domegrowth and pyroclastic flows have also occurred.
NEVADO DEL RUIZ, Colombia
4.895°N, 75.322°W; summit elev. 5321 m
Based on analysis of satellite imagery, the Washington VAAC reported that on 16 January a diffuse plume from Nevado del Ruiz possibly contained ash and drifted almost 55 km NE. A thermal anomaly was also detected.INGEOMINAS reported significant emissions of mostly gas and steam during 14-20 January; plumes rose 1.6 km above the crater and drifted E and SE, and then W during the later part of the week.
Geologic summary: Nevado del Ruiz is a broad, glacier-covered volcano in central Colombia that covers >200 sq km. Three major edifices, composed of andesitic and dacitic lavas and andesitic pyroclastics, have been constructed since the beginning of the Pleistocene. The modern cone consists of a broad cluster of lava domes built within the summit caldera of an older Ruiz volcano. The 1-km-wide, 240-m-deep Arenas crater occupies the summit. Steep headwalls of massive landslides cut the flanks of Nevado del Ruiz. Melting of its summit icecap during historical eruptions, which date back to the 16th century, has resulted in devastating lahars, including one in 1985 that was South America's deadliest eruption.
31.585°N, 130.657°E; summit elev. 1117 m
JMA reported that during 15-18 January explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. A very small eruption occurred at Minami-dake Crater on 15 January.
Based on information from JMA, the Tokyo VAAC reported that explosions during 16-21 January often generated plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted NE, E, SE, and S. A pilot reported that an ash plume drifted SE at an altitude of 2.4 km (8,000 ft) a.s.l. on 19 January.
Geologic summary: Sakura-jima, one of Japan's most active volcanoes, is a post-caldera cone of the Aira calderaat 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 depositedash 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 11-18 January a viscouslava flow effused on the E flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, andfumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. The Aviation Color Coderemained 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.
TOLBACHIK, Central Kamchatka (Russia)
55.830°N, 160.330°E; summit elev. 3682 m
KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a lava plateau on the SW side of Tolbachik, continued to produce very fluid lava flows during 11-18 January that traveled to the W and S sides of Tolbachinsky Dol. Gas-and-ash plumes rose to an altitude of 4 km (13,100 ft) a.s.l. and drifted in multiple directions. A very large thermal anomaly on the N part of Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color Code remained at Orange.
Geologic summary: The massive Tolbachik basaltic volcano is located at the southern end of the dominantlyandesitic 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-typecalderas 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.
Source: Global Volcanism Program
Featured image: Taro Taylor - CC BY 2.0