5-5-5-5-5-5-5-5-5-5-5-5-5-5 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 12-18 February 2025 Sally Sennert - Weekly Report Editor (kuhns@xxxxxx) URL: https://volcano.si.edu/reports_weekly.cfm <https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Toy0-uF9IA$> New Activity/Unrest: Bezymianny, Russia | Etna, Italy | Kilauea, United States | Lascar, Chile | Lewotobi, Indonesia | Lewotolok, Indonesia | Poas, Costa Rica Ongoing Activity: Ahyi, United States | Aira, Japan | Dukono, Indonesia | El Misti, Peru | Great Sitkin, United States | Huaynaputina, Peru | Ibu, Indonesia | Kanlaon, Philippines | Karymsky, Russia | Merapi, Indonesia | Sabancaya, Peru | Semeru, Indonesia | Sheveluch, Russia | Suwanosejima, Japan | Taal, Philippines 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, these reports 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 about recent activity are published in issues of the Bulletin of the Global Volcanism Network. Note that 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 Bezymianny | Russia | 55.972°N, 160.595°E | Summit elev. 2882 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that a thermal anomaly over Bezymianny was identified in satellite images during 6-13 February. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are reported in UTC; specific events are in local time where noted. Geologic Summary. The modern Bezymianny, much smaller than its massive neighbors Kamen and Kliuchevskoi on the Kamchatka Peninsula, was formed about 4,700 years ago over a late-Pleistocene lava-dome complex and an edifice built about 11,000-7,000 years ago. Three periods of intensified activity have occurred during the past 3,000 years. The latest period, which was preceded by a 1,000-year quiescence, began with the dramatic 1955-56 eruption. This eruption, similar to that of St. Helens in 1980, produced a large open crater that was formed by collapse of the summit and an associated lateral blast. Subsequent episodic but ongoing lava-dome growth, accompanied by intermittent explosive activity and pyroclastic flows, has largely filled the 1956 crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5ToxCQ5WwDg$> Etna | Italy | 37.748°N, 14.999°E | Summit elev. 3357 m Sezione di Catania - Osservatorio Etneo (INGV) reported that the new eruption that began at Etna on 6 February continued during 10-16 February. Activity observed through webcams and during daily field inspections was characterized by the effusion of a lava flow from a fissure and explosive activity at the summit. The lava flow from the fissure that opened at the base of Bocca Nuova Crater on 8 February continued to effuse lava. The lava flow advanced down the SW flank, descending to 2,150 elevation by 11 February and 1,960 elevation by 13 February. The distal end of the flow was 6-8 m thick. Photogrammetric data collected by drones on 14 and 16 February, combined with satellite data, showed that the lava flow advanced 380 m during that 48-hour period. The total flow length was 4.2 km and covered an estimated area of 0.3 square kilometers (300,000 square meters). There were reports of phreatic explosions from the interaction with lava and snow that ejected lava fragments a few hundred meters, particularly on 12 February. Explosive activity at SE Crater originated from at least two vents based on webcam views and a 12 February field inspection. During the field inspection weak explosive activity originated from a vent located between SE Crater and Bocca Nuova Crater. Minor ash emissions rose from SE Crater and quickly dissipated downwind, depositing ash near the summit. Ash emissions intensified on 12, 14, and 16 February; the Aviation Color Code was raised to Red (the highest level on a four-color scale) on 12 February then back to Orange on 13 February, to Red on 14 February and back to Orange that same day, again to Red on 16 February, and back to orange on 18 February. Although weather conditions sometimes obscured views, the ash emissions rose no higher than an estimated maximum altitude of 5.5 km a.s.l. (about 2.1 km above the summit). According to a news report flights in and out of the Catania-Fontanarossa Airport were disrupted during 12-17 February. Geologic Summary. Mount Etna, towering above Catania on the island of Sicily, has one of the world's longest documented records of volcanism, dating back to 1500 BCE. Historical lava flows of basaltic composition cover much of the surface of this massive volcano, whose edifice is the highest and most voluminous in Italy. The Mongibello stratovolcano, truncated by several small calderas, was constructed during the late Pleistocene and Holocene over an older shield volcano. The most prominent morphological feature of Etna is the Valle del Bove, a 5 x 10 km caldera open to the east. Two styles of eruptive activity typically occur, sometimes simultaneously. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more summit craters. Flank vents, typically with higher effusion rates, are less frequently active and originate from fissures that open progressively downward from near the summit (usually accompanied by Strombolian eruptions at the upper end). Cinder cones are commonly constructed over the vents of lower-flank lava flows. Lava flows extend to the foot of the volcano on all sides and have reached the sea over a broad area on the SE flank. Sources: Sezione di Catania - Osservatorio Etneo (INGV) http://www.ct.ingv.it/ <https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Tozbs38prw$> ; Euronews https://www.euronews.com/travel/2025/02/14/mount-etna-volcanic-eruption-closes-catania-international-airport <https://urldefense.com/v3/__https://www.euronews.com/travel/2025/02/14/mount-etna-volcanic-eruption-closes-catania-international-airport__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5TozPdi-RdQ$> Kilauea | United States | 19.421°N, 155.287°W | Summit elev. 1222 m The Hawaiian Volcano Observatory (HVO) reported that the eruption within Kilaueaâ??s Kaluapele summit caldera, from vents along the SW margin of Halemaâ??umaâ??u Crater, continued at variable levels during 11-18 February. A period of lava fountaining and effusion of lava onto the crater floor began at 1016 on 11 February and lasted more than 22 hours. Lava fountains rose as high as 100 m at the N vent and were bifurcated at the S vent, rising as high as 30 m. Both effusion rates and lava-fountain heights decreased by the morning of 12 February. Lava fountaining stopped at the N vent at 0830 and within a few minutes fountaining at the S vent was less vigorous. A small amount of lava continued to effuse from the S vent then completely ceased at 0843. Lava flows had traveled about 1 km across the crater floor, covering 50-60% of the surface. Overnight during 12-13 February several lava flows slowly moved on the crater floor. During 12-18 February areas of incandescence and gas emissions at the N vent and incandescence from cooling lava flows on the crater floor were visible. Incandescence and gas emissions were also visible at the S vent during 15-18 February. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale). Geologic Summary. Kilauea overlaps the E flank of the massive Mauna Loa shield volcano in the island of Hawaii. Eruptions are prominent in Polynesian legends; written documentation since 1820 records frequent summit and flank lava flow eruptions interspersed with periods of long-term lava lake activity at Halemaumau crater in the summit caldera until 1924. The 3 x 5 km caldera was formed in several stages about 1,500 years ago and during the 18th century; eruptions have also originated from the lengthy East and Southwest rift zones, which extend to the ocean in both directions. About 90% of the surface of the basaltic shield volcano is formed of lava flows less than about 1,100 years old; 70% of the surface is younger than 600 years. The long-term eruption from the East rift zone between 1983 and 2018 produced lava flows covering more than 100 km2, destroyed hundreds of houses, and added new coastline. Source: US Geological Survey Hawaiian Volcano Observatory (HVO) https://volcanoes.usgs.gov/observatories/hvo/ <https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Tox6hIru9A$> Lascar | Chile | 23.37°S, 67.73°W | Summit elev. 5592 m On 6 February the Servicio Nacional de GeologÃa y MinerÃa (SERNAGEOMIN) issued a special report noting increased emissions at Láscar. A whitish-colored gas plume observed in webcam views rose almost 2 km above the summit. Sulfur dioxide emissions detected in satellite data were 188 tons per day which was characterized as atypical during the previous year. A thermal anomaly in the crater was identified in satellite data suggesting an increase in temperature within the crater. Seismicity did not clearly indicate variations that may be related to unrest, though two long-period earthquakes were recorded on 7 and 9 February. Sulfur dioxide emissions increased to 752 tons on 11 February. On 12 February the Alert Level was raised to Yellow (the second lowest level on a four-color scale) and the public was warned to stay at least 1 km away from the crater. Geologic Summary. Láscar is the most active volcano of the northern Chilean Andes. The andesitic-to-dacitic stratovolcano contains six overlapping summit craters. Prominent lava flows descend its NW flanks. An older, higher stratovolcano 5 km E, Volcán Aguas Calientes, displays a well-developed summit crater and a probable Holocene lava flow near its summit (de Silva and Francis, 1991). Láscar consists of two major edifices; activity began at the eastern volcano and then shifted to the western cone. The largest eruption took place about 26,500 years ago, and following the eruption of the Tumbres scoria flow about 9000 years ago, activity shifted back to the eastern edifice, where three overlapping craters were formed. Frequent small-to-moderate explosive eruptions have been recorded since the mid-19th century, along with periodic larger eruptions that produced ashfall hundreds of kilometers away. The largest historical eruption took place in 1993, producing pyroclastic flows to 8.5 km NW of the summit and ashfall in Buenos Aires. Source: Servicio Nacional de GeologÃa y MinerÃa (SERNAGEOMIN) http://www.sernageomin.cl/ <https://urldefense.com/v3/__http://www.sernageomin.cl/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5TozH708Xfw$> Lewotobi | Indonesia | 8.542°S, 122.775°E | Summit elev. 1703 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity continued at Lewotobi Laki-laki during 12-18 February. A sudden increase in the number of volcanic earthquakes was detected at 2200 on 11 February and the seismicity remained at high levels. At 0300 on 12 February the exclusion zone was expanded to a radius of 5 km from the center of Laki-laki and 6 km in a semicircle counterclockwise from the NE to the SW. The Alert Level was raised to 4 (on a scale of 1-4) at 0300 on 13 February and the exclusion zone was again expanded to 6 km from the center of Laki-laki and 7 km in a semicircle counterclockwise from the NE to the SW. PVMBG noted that during 3 January-13 February the seismic network also detected increases in harmonic tremor, low-frequency earthquakes, and shallow volcanic earthquakes. Observable activity also increased and fumarolic plumes rose from cracks on the upper NW flank, though weather conditions often obscured views. Crater incandescence was visible, but often faint. BNPB recommended that residents evacuate from the six villages within the expanded exclusion zone including Nobo (5 km NE), Dulipali (6 km NNW), and Hokeng Jaya (3 km WNW). During 13-17 February dense white plumes rose 400-600 m above the summit. Seismicity fluctuated, but notably deep volcanic earthquakes were recorded during 16-17 February while shallow volcanic earthquakes were not. At 0558, 1622, and 2343 on 17 February dense gray ash plumes rose 400-900 m above the summit and drifted N and NE. Geologic Summary. The Lewotobi edifice in eastern Flores Island is composed of the two adjacent Lewotobi Laki-laki and Lewotobi Perempuan stratovolcanoes (the "husband and wife"). Their summits are less than 2 km apart along a NW-SE line. The conical Laki-laki to the NW has been frequently active during the 19th and 20th centuries, while the taller and broader Perempuan has had observed eruptions in 1921 and 1935. Small lava domes have grown during the 20th century in both of the summit craters, which are open to the north. A prominent cone, Iliwokar, occurs on the E flank of Perampuan. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5ToxkxP4HOQ$> ; Badan Nacional Penanggulangan Bencana (BNPB) http://www.bnpb.go.id/ <https://urldefense.com/v3/__http://www.bnpb.go.id/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Toz-8B1zHw$> Lewotolok | Indonesia | 8.274°S, 123.508°E | Summit elev. 1431 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that at 0200 on 16 February an eruptive event at Lewotolok generated a gray ash plume that rose around 200 m above the summit and drifted E. At 0922 on 16 February and at 0012 on 17 February dense white-and-gray ash plumes rose 100-200 m and drifted E and SE, respectively. Incandescence at the summit was visible in a webcam image from 0013 on 17 February. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 2 km away from the vent and 2.5 km away on the S, SE, and W flanks. Geologic Summary. The Lewotolok (or Lewotolo) stratovolcano occupies the eastern end of an elongated peninsula extending north into the Flores Sea, connected to Lembata (formerly Lomblen) Island by a narrow isthmus. It is symmetrical when viewed from the north and east. A small cone with a 130-m-wide crater constructed at the SE side of a larger crater forms the volcano's high point. Many lava flows have reached the coastline. Eruptions recorded since 1660 have consisted of explosive activity from the summit crater. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5ToxkxP4HOQ$> Poas | Costa Rica | 10.2°N, 84.233°W | Summit elev. 2697 m The Observatorio Vulcanológico y Sismológico de Costa Rica-Universidad Nacional (OVSICORI-UNA) reported that eruptive activity at Poás was recorded during 11-18 February. The lake water level had dropped about 0.3 m in a week and convection cells over underwater fumarolic vents persisted; convecting water over Boca C vent was noted during 11-12 February. Sulfur dioxide gas flux significantly increased to 445 +/- 504 tons per day (t/d) on 13 February and was higher than the average of 267 +/- 97 t/d detected during the previous week. Frequent (every minute) phreatic explosions at Boca C were recorded during 15-17 February based on seismic and acoustic data. Material was ejected above the lakeâ??s surface as high as 200 m. Sulfur dioxide emissions had decreased by 16 February. The frequency of phreatic explosions decreased during 17-18 February, though events were characterized as both intense and low magnitude, with ejected material rising less than 200 m. Geologic Summary. The broad vegetated edifice of Poás, one of the most active volcanoes of Costa Rica, contains three craters along a N-S line. The frequently visited multi-hued summit crater lakes of the basaltic-to-dacitic volcano are easily accessible by vehicle from the nearby capital city of San José. A N-S-trending fissure cutting the complex stratovolcano extends to the lower N flank, where it has produced the Congo stratovolcano and several lake-filled maars. The southernmost of the two summit crater lakes, Botos, last erupted about 7,500 years ago. The more prominent geothermally heated northern lake, Laguna Caliente, is one of the world's most acidic natural lakes, with a pH of near zero. It has been the site of frequent phreatic and phreatomagmatic eruptions since an eruption was reported in 1828. Eruptions often include geyser-like ejections of crater-lake water. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) http://www.ovsicori.una.ac.cr/ <https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Toxn9LSixA$> Ongoing Activity Ahyi | United States | 20.42°N, 145.03°E | Summit elev. -75 m Unrest at Ahyi Seamount continued during 7-13 February. A satellite image on 8 February showed a plume of discolored water in the vicinity of the seamount, indicating possible submarine activity. The Aviation Color Code remained at Yellow (the second lowest level on a four-color scale) and the Volcano Alert Level remained at Advisory (the second lowest level on a four-level scale). Geologic Summary. Ahyi seamount is a large conical submarine volcano that rises to within 75 m of the ocean surface ~18 km SE of the island of Farallon de Pajaros in the northern Marianas. Water discoloration has been observed there, and in 1979 the crew of a fishing boat felt shocks over the summit area, followed by upwelling of sulfur-bearing water. On 24-25 April 2001 an explosive eruption was detected seismically by a station on Rangiroa Atoll, Tuamotu Archipelago. The event was well constrained (+/- 15 km) at a location near the southern base of Ahyi. An eruption in April-May 2014 was detected by NOAA divers, hydroacoustic sensors, and seismic stations. Source: US Geological Survey https://www.usgs.gov/ <https://urldefense.com/v3/__https://www.usgs.gov/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5ToyoCHe4lg$> Aira | Japan | 31.5772°N, 130.6589°E | Summit elev. 1117 m The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Calderaâ??s Sakurajima volcano) during 10-17 February. Nightly crater incandescence was visible in webcam images. On 10 February sulfur dioxide emissions were high, averaging 2,200 tons per day. Six eruptive events, recorded during 11 and 15-16 February, produced ash plumes that rose 1-1.2 km above the summit and drifted SE, E, and NE. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 1 km away from both craters. Geologic Summary. The Aira caldera in the northern half of Kagoshima Bay contains the post-caldera Sakurajima volcano, one of Japan's most active. Eruption of the voluminous Ito pyroclastic flow accompanied formation of the 17 x 23 km caldera about 22,000 years ago. The smaller Wakamiko caldera was formed during the early Holocene in the NE corner of the caldera, along with several post-caldera cones. The construction of Sakurajima began about 13,000 years ago on the southern rim and built an island that was joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kitadake summit cone ended about 4,850 years ago, after which eruptions took place at Minamidake. Frequent eruptions since the 8th century have deposited ash on the city of Kagoshima, located across Kagoshima Bay only 8 km from the summit. The largest recorded eruption took place during 1471-76. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5TowPk0skig$> Dukono | Indonesia | 1.6992°N, 127.8783°E | Summit elev. 1273 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Dukono was ongoing during 12-18 February. Daily white-and-gray ash plumes rose 100-1,500 m above the crater rim and drifted in multiple directions. The Alert Level remained at Level 2 (on a scale of 1-4) and the public was warned to stay 4 km away from the Malupang Warirang Crater. 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, have occurred since 1933. During a major eruption in 1550 CE, a lava flow filled in the strait between Halmahera and the N-flank Gunung Mamuya cone. This complex volcano presents a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also been active during historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5ToxkxP4HOQ$> El Misti | Peru | 16.294°S, 71.409°W | Summit elev. 5822 m The Instituto GeofÃsico del Perú (IGP) reported that three lahars carrying blocks traveled down El Mistiâ??s flanks on 15 February. The first descended the Matagente drainage on the NW flank at 1637, the second descended the El Pato drainage on the SW flank at 1750, and the third descended the Huarangal-Los Incas drainage on the SW flank at 1820. The public was warned to stay away from drainages and roads on the SW flank. The Alert Level remained at Green (the lowest level on a four-color scale). Geologic Summary. El Misti is a symmetrical andesitic stratovolcano with nested summit craters that towers above the city of Arequipa, Peru. The modern symmetrical cone, constructed within a small 1.5 x 2 km wide summit caldera that formed between about 13,700 and 11,300 years ago, caps older Pleistocene volcanoes that underwent caldera collapse about 50,000 years ago. A large scoria cone has grown with the 830-m-wide outer summit crater. At least 20 tephra-fall deposits and numerous pyroclastic-flow deposits have been documented during the past 50,000 years, including a pyroclastic flow that traveled 12 km to the south about 2000 years ago. The most recent activity has been dominantly pyroclastic, and strong winds have formed a parabolic dune field of volcanic ash extending up to 20 km downwind. An eruption in the 15th century affected nearby Inca inhabitants. Some reports of historical eruptions may represent increased fumarolic activity. Source: Instituto GeofÃsico del Perú (IGP) http://www.igp.gob.pe/ <https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Tozhy_dB3g$> Great Sitkin | United States | 52.076°N, 176.13°W | Summit elev. 1740 m The Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick lava flow in Great Sitkinâ??s summit crater, confirmed by a 10 February radar image. The lava flow advanced along the NNE margin. Small daily earthquakes were detected by the seismic network during 10-18 February. Weakly elevated surface temperatures were identified in satellite data during 15-18 February. Cloudy weather obscured satellite and webcam images during most of the week. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale). Geologic Summary. The Great Sitkin volcano forms much of the northern side of Great Sitkin Island. A younger volcano capped by a small, 0.8 x 1.2 km ice-filled summit caldera was constructed within a large late-Pleistocene or early Holocene scarp formed by massive edifice failure that truncated an older edifice and produced a submarine debris avalanche. Deposits from this and an even older debris avalanche from a source to the south cover a broad area of the ocean floor north of the volcano. The summit lies along the eastern rim of the younger collapse scarp. Deposits from an earlier caldera-forming eruption of unknown age cover the flanks of the island to a depth up to 6 m. The small younger caldera was partially filled by lava domes emplaced in 1945 and 1974, and five small older flank lava domes, two of which lie on the coastline, were constructed along northwest- and NNW-trending lines. Hot springs, mud pots, and fumaroles occur near the head of Big Fox Creek, south of the volcano. Eruptions have been recorded since the late-19th century. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://avo.alaska.edu/ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5TowNcFwWJw$> Huaynaputina | Peru | 16.6144°S, 70.8542°W | Summit elev. 4679 m The Instituto GeofÃsico del Perú (IGP) reported that several lahars carrying blocks descended the S flank of Huaynaputina during 11-17 February and traveled towards the Tambo River. The lahars were recorded at 1309 on 11 February, at 1725 on 14 February, at 1712 on 15 February, at 1813 on 16 February, and at 1546 on 17 February. The public was warned to stay away from the drainage and to be cautious when traveling along the Quinistaquillas-Sijuaya highway. Geologic Summary. Huaynaputina (whose name means "new volcano") was the source of the largest historical eruption of South America in 1600 CE. It has no prominent topographic expression and lies within a 2.5-km-wide collapse depression and further excavated by glaciers within a Tertiary to Pleistocene edifice. Three overlapping ash cones with craters up to 100 m deep were constructed during the 1600 CE eruption on the floor of the older crater, whose outer flanks are heavily mantled by ash deposits from the 1600 eruption. This powerful fissure-fed eruption may have produced nearly 30 km3 of dacitic tephra, including pyroclastic flows and surges that traveled 13 km to the E and SE. Lahars reached the Pacific Ocean, 120 km away. The eruption caused substantial damage to the major cities of Arequipa and Moquengua. Source: Instituto GeofÃsico del Perú (IGP) http://www.igp.gob.pe/ <https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Tozhy_dB3g$> Ibu | Indonesia | 1.488°N, 127.63°E | Summit elev. 1325 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 12-18 February. Multiple daily gray or white-and-gray ash plumes that were often dense rose as high as 1.5 km above the summit and drifted mainly in multiple directions. Incandescence at the summit was visible in some webcam images posted with the reports. The Alert Level remained at 3 (the second highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 5 km away from the N crater wall opening. Geologic Summary. The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, has contained several small crater lakes. The 1.2-km-wide outer crater is breached on the N, creating a steep-walled valley. A large cone grew ENE of the summit, and a smaller one to the WSW has fed a lava flow down the W flank. A group of maars is located below the N and W flanks. The first observed and recorded eruption was a small explosion from the summit crater in 1911. Eruptive activity began again in December 1998, producing a lava dome that eventually covered much of the floor of the inner summit crater along with ongoing explosive ash emissions. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5ToxkxP4HOQ$> Kanlaon | Philippines | 10.4096°N, 123.13°E | Summit elev. 2422 m The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing eruptive activity at Kanlaon during 11-18 February. The seismic network recorded 7-19 daily volcanic earthquakes, though during 15-16 February there were 29-32 daily events. Average daily sulfur dioxide emissions ranged from 2,148 to 4,685 tonnes per day (t/d); emissions since 3 June 2024 averaged 4,440 t/d. Gas-and-steam emissions generally rose as high as 200 m above the summit and drifted W, WSW, and SW; plumes occasionally contained ash during 11 and 14-15 February. Eruptive activity during 1432-1440 on 15 February sent an ash plume 1.5 km above the summit that drifted WNW. Ashfall and sulfur odors were reported in multiple neighborhoods of Bago City including in Mailum, Maao, Binubuhan, Abuanan, Dulao, Atipuluan, and Ilijan. PHIVOLCS noted that since 10 January the deformation network had detected inflation of the upper E flank and cycles of inflation and deflation at the upper W flank and mid E flank. The Alert Level remained at 3 (on a scale of 0-5); the public was warned to stay 6 km away from the summit and pilots were warned not to fly close to the volcano. Geologic Summary. Kanlaon volcano (also spelled Canlaon) forms the highest point on the Philippine island of Negros. The massive andesitic stratovolcano is covered with fissure-controlled pyroclastic cones and craters, many of which are filled by lakes. The largest debris avalanche known in the Philippines traveled 33 km SW from Kanlaon. The summit contains a 2-km-wide, elongated northern caldera with a crater lake and a smaller but higher active vent, Lugud crater, to the south. Eruptions recorded since 1866 have typically consisted of phreatic explosions of small-to-moderate size that produce minor local ashfall. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS) http://www.phivolcs.dost.gov.ph/ <https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Toya41wTZA$> Karymsky | Russia | 54.049°N, 159.443°E | Summit elev. 1513 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported moderate levels of activity at Karymsky during 6-13 February. A weak thermal anomaly over the volcano was identified in satellite images during 6 and 9-13 February; weather clouds obscured views on the other days. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. 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 during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-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. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5ToxCQ5WwDg$> Merapi | Indonesia | 7.54°S, 110.446°E | Summit elev. 2910 m The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 7-13 February. Seismicity remained at high levels. The SW lava dome produced 59 lava avalanches that traveled as far as 2 km SW down the Bebeng drainage, 12 that traveled as far as 1.8 km SW down the Krasak drainage, and 24 that traveled as far as 1.8 km SW down the Sat/Putih drainage. Morphological changes at the SW dome were caused by continuing effusion and collapses of material. No significant morphological changes at the summit dome were visible. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location. Geologic Summary. Merapi, one of Indonesia's most active volcanoes, lies in one of the world's most densely populated areas and dominates the landscape immediately north of the major city of Yogyakarta. It is the youngest and southernmost of a volcanic chain extending NNW to Ungaran volcano. Growth of Old Merapi during the Pleistocene ended with major edifice collapse perhaps about 2,000 years ago, leaving a large arcuate scarp cutting the eroded older Batulawang volcano. Subsequent growth of the steep-sided Young Merapi edifice, its upper part unvegetated due to frequent activity, began SW of the earlier collapse scarp. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated lands on the western-to-southern flanks and caused many fatalities. Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) http://www.merapi.bgl.esdm.go.id/ <https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5TowrfmJGKQ$> Sabancaya | Peru | 15.787°S, 71.857°W | Summit elev. 5960 m The Instituto GeofÃsico del Perú (IGP) reported that the eruption at Sabancaya continued during 10-16 February with an average of one explosion per day. Gas-and-ash plumes rose as high as 1.2 km above the summit and drifted less than 10 km W, SW, and NW. Thermal anomalies over the lava dome in the summit crater were identified in satellite data. Sulfur dioxide emissions were at moderate levels, averaging 764 tons per day. No thermal anomalies or significant deformation were detected. The Alert Level remained at Orange (the third level on a four-color scale) and the public was warned to stay outside of a 12 km radius from the summit. Geologic Summary. Sabancaya, located in the saddle NE of Ampato and SE of Hualca Hualca volcanoes, is the youngest of these volcanic centers and the only one to have erupted in historical time. The oldest of the three, Nevado Hualca Hualca, is of probable late-Pliocene to early Pleistocene age. The name Sabancaya (meaning "tongue of fire" in the Quechua language) first appeared in records in 1595 CE, suggesting activity prior to that date. Holocene activity has consisted of Plinian eruptions followed by emission of voluminous andesitic and dacitic lava flows, which form an extensive apron around the volcano on all sides but the south. Records of observed eruptions date back to 1750 CE. Source: Instituto GeofÃsico del Perú (IGP) http://www.igp.gob.pe/ <https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Tozhy_dB3g$> Semeru | Indonesia | 8.108°S, 112.922°E | Summit elev. 3657 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity continued at Semeru during 12-18 February with daily eruptive events recorded by the seismic network. Daily white-and-gray ash plumes rose 500-1,000 m above the summit and drifted in multiple directions. The Alert Level remained at 2 (the second lowest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards. Geologic Summary. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5ToxkxP4HOQ$> Sheveluch | Russia | 56.653°N, 161.36°E | Summit elev. 3283 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that lava extrusion may have continued at Sheveluchâ??s â??300 years of RASâ?? dome on the SW flank of Old Sheveluch and at the Young Sheveluch dome during 6-13 February. Daily thermal anomalies over the domes were identified in satellite images. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. The high, isolated massif of Sheveluch volcano (also spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group. The 1,300 km3 andesitic volcano is one of Kamchatka's largest and most active volcanic structures, with at least 60 large eruptions during the Holocene. The summit of roughly 65,000-year-old Stary Shiveluch is truncated by a broad 9-km-wide late-Pleistocene caldera breached to the south. Many lava domes occur on its outer flanks. The Molodoy Shiveluch lava dome complex was constructed during the Holocene within the large open caldera; Holocene lava dome extrusion also took place on the flanks of Stary Shiveluch. Widespread tephra layers from these eruptions have provided valuable time markers for dating volcanic events in Kamchatka. Frequent collapses of dome complexes, most recently in 1964, have produced debris avalanches whose deposits cover much of the floor of the breached caldera. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5ToxCQ5WwDg$> Suwanosejima | Japan | 29.638°N, 129.714°E | Summit elev. 796 m The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 10-17 February. Incandescence was observed nightly in webcam images. An eruptive event at 1644 on 11 February generated an ash plume that rose 1 km above the summit and drifted SE. An explosion later that same day at 2007 generated an ash plume that rose 1.1 km above the crater rim and drifted SE. Ash fell within a 10-km-radius of the crater on unspecified dates according to the Suwanosejima Branch of the Toshima Village Office (3.5 km SSW). The Alert Level remained at 2 (the second level on a five-level scale) and the public was warned to stay at least 1.5 km away from the crater. Geologic Summary. The 8-km-long island of Suwanosejima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two active summit craters. The summit is truncated by a large breached crater extending to the sea on the E flank that was formed by edifice collapse. One of Japan's most frequently active volcanoes, it was in a state of intermittent Strombolian activity from Otake, the NE summit crater, between 1949 and 1996, after which periods of inactivity lengthened. The largest recorded eruption took place in 1813-14, when thick scoria deposits covered residential areas, and the SW crater produced two lava flows that reached the western coast. At the end of the eruption the summit of Otake collapsed, forming a large debris avalanche and creating an open collapse scarp extending to the eastern coast. The island remained uninhabited for about 70 years after the 1813-1814 eruption. Lava flows reached the eastern coast of the island in 1884. Only about 50 people live on the island. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5TowPk0skig$> Taal | Philippines | 14.0106°N, 120.9975°E | Summit elev. 311 m The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing eruptive activity at Taal during 11-18 February. There were 0-12 daily volcanic earthquakes and a few periods of tremor that lasted from one minute to as long as two hours and nine minutes. Three minor phreatic eruptions occurred on 12, 15, and 16 February, each lasting 3-4 minutes. Daily gas-and-steam emissions generally rose 350-900 m above the crater rim and drifted NW, W, and SW, though on 16 February plumes rose as high as 2.1 km. Sulfur dioxide emissions averaged 448, 407, and 1,244 tonnes per day on 12, 15, and 17 February, respectively. The Alert Level remained at 1 (on a scale of 0-5); PHIVOLCS reminded the public that the entire Taal Volcano Island was a Permanent Danger Zone (PDZ) and recommended that the Main Crater and areas along the Daang Kastila fissure should remain prohibited. Geologic Summary. Taal is one of the most active volcanoes in the Philippines and has produced some powerful eruptions. The 15 x 20 km Talisay (Taal) caldera is largely filled by Lake Taal, whose 267 km2 surface lies only 3 m above sea level. The maximum depth of the lake is 160 m, with several submerged eruptive centers. The 5-km-wide Volcano Island in north-central Lake Taal is the location of all observed eruptions. The island is composed of coalescing small stratovolcanoes, tuff rings, and scoria cones. Powerful pyroclastic flows and surges have caused many fatalities. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS) http://www.phivolcs.dost.gov.ph/ <https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!Yx88_CNUd7AmEC7jVniO5Sv5rmfKwPFSMg9XJfFFcKbTp4iLACYsev6YrKe3VnwSDbc_VrrSmkjtqto5Toya41wTZA$> 5-5-5-5-5-5-5-5-5-5-5-5-5-5 ============================================================== Volcano Listserv is a collaborative venture among Arizona State University (ASU), Portland State University (PSU), the Global Volcanism Program (GVP) of the Smithsonian Institution's National Museum of Natural History, and the International Association for Volcanology and Chemistry of the Earth's Interior (IAVCEI). 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