2-2-2-2-2-2-2-2-2-2-2-2-2 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 12-18 March 2025 Sally Sennert - Weekly Report Editor (kuhns@xxxxxx) Tricia Light - contributor (tlight@xxxxxxxx) URL: https://volcano.si.edu/reports_weekly.cfm <https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9yP3OIXRg$> New Activity/Unrest: Fuego, Guatemala | Langila, Papua New Guinea | Lascar, Chile | Lewotolok, Indonesia | Manam, Papua New Guinea | Poas, Costa Rica | Raung, Indonesia | Turrialba, Costa Rica Ongoing Activity: Ahyi, United States | Aira, Japan | Bezymianny, Russia | Dukono, Indonesia | Etna, Italy | Great Sitkin, United States | Ibu, Indonesia | Kanlaon, Philippines | Karymsky, Russia | Katmai, United States | Kilauea, United States | Lewotobi, Indonesia | Marapi, Indonesia | Merapi, Indonesia | Reventador, Ecuador | Rincon de la Vieja, Costa Rica | Sangay, Ecuador | Santa Maria, Guatemala | Semeru, Indonesia | Sheveluch, Russia | Spurr, United States | Stromboli, Italy | Suwanosejima, 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, 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 Fuego | Guatemala | 14.4748°N, 90.8806°W | Summit elev. 3799 m The Instituto Nacional de SismologÃa, VulcanologÃa, MeteorologÃa e HidrologÃa (INSIVUMEH) reported that after the elevated eruptive activity at Fuego during 9-10 March, low-level unrest persisted through 18 March. Gas-and-steam plumes that were mostly diffuse rose as high as 700 m above the summit and drifted in multiple directions. Incandescence at the crater was sometimes visible during dark hours likely from blocks emplaced during the eruption. Geologic Summary. Volcán Fuego, one of Central America's most active volcanoes, is also one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between Fuego and Acatenango to the north. Construction of Meseta dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at the mostly andesitic Acatenango. Eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. Frequent vigorous eruptions have been recorded since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) http://www.insivumeh.gob.gt/ <https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zMh1nQmw$> Langila | Papua New Guinea | 5.525°S, 148.42°E | Summit elev. 1330 m The Darwin Volcanic Ash Advisory Centre (VAAC) reported that an ash plume from Langila rose to 3 km (10,000 ft) a.s.l. at 1530 on 13 March and drifted S based on a pilot report; weather clouds obscured satellite views. A satellite image at 2210 indicated that the ash had dissipated. Geologic Summary. Langila, one of the most active volcanoes of New Britain, consists of a group of four small overlapping composite basaltic-andesitic cones on the lower E flank of the extinct Talawe volcano in the Cape Gloucester area of NW New Britain. A rectangular, 2.5-km-long crater is breached widely to the SE; Langila 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. The youngest and smallest crater (no. 3 crater) was formed in 1960 and has a diameter of 150 m. Source: Darwin Volcanic Ash Advisory Centre (VAAC) http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml <https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9xSnUyniA$> Lascar | Chile | 23.37°S, 67.73°W | Summit elev. 5592 m The Servicio Nacional de GeologÃa y MinerÃa (SERNAGEOMIN) reported continuing unrest at Láscar. A thermal anomaly in the crater detected on 16 March was the most intense anomaly recorded in the previous month. Other satellite data continued to show three zones of elevated temperatures in the crater. Whitish gas emissions persisted. The seismic network recorded a decrease of long-period earthquakes beginning in early February. The Alert Level remained at Yellow (the second lowest level on a four-color scale) and the public was warned to stay at least 1 km away from the crater. Geologic Summary. Láscar is the most active volcano of the northern Chilean Andes. The andesitic-to-dacitic stratovolcano contains six overlapping summit craters. Prominent lava flows descend its NW flanks. An older, higher stratovolcano 5 km E, Volcán Aguas Calientes, displays a well-developed summit crater and a probable Holocene lava flow near its summit (de Silva and Francis, 1991). Láscar consists of two major edifices; activity began at the eastern volcano and then shifted to the western cone. The largest eruption took place about 26,500 years ago, and following the eruption of the Tumbres scoria flow about 9000 years ago, activity shifted back to the eastern edifice, where three overlapping craters were formed. Frequent small-to-moderate explosive eruptions have been recorded since the mid-19th century, along with periodic larger eruptions that produced ashfall hundreds of kilometers away. The largest historical eruption took place in 1993, producing pyroclastic flows to 8.5 km NW of the summit and ashfall in Buenos Aires. Source: Servicio Nacional de GeologÃa y MinerÃa (SERNAGEOMIN) http://www.sernageomin.cl/ <https://urldefense.com/v3/__http://www.sernageomin.cl/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zaoVX3Fg$> Lewotolok | Indonesia | 8.274°S, 123.508°E | Summit elev. 1431 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that an eruption at Lewotolok was ongoing during 12-18 March. Daily white steam-and-gas plumes rose as high as 500 m above the summit and drifted in multiple directions. At 0700 on 14 March a white-and-gray ash plume rose about 400 m above the summit and drifted NW. At 1515 and 1559 on 15 March gray ash plumes rose 500 and 600 m above the summit and drifted NW and NE, respectively. Seismicity significantly increased during 16-17 March. 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!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zAHd8AFw$> Manam | Papua New Guinea | 4.08°S, 145.037°E | Summit elev. 1807 m The Darwin Volcanic Ash Advisory Centre (VAAC) reported that an ash plume from Manam was identified in a satellite image at 1230 on 15 March drifting NNW. The plume had dissipated by 1510. Geologic Summary. The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical basaltic-andesitic stratovolcano to its lower flanks. These valleys channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Five small satellitic centers are located near the island's shoreline on the northern, southern, and western sides. Two summit craters are present; both are active, although most observed eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE valley. Frequent eruptions, typically of mild-to-moderate scale, have been recorded since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas. Source: Darwin Volcanic Ash Advisory Centre (VAAC) http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml <https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9xSnUyniA$> 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 continued at an elevated level through 18 March. Four significant phreatic eruptions were recorded on 9 March that ejected material as high as 300 m above the lakeâ??s surface and produced a steam-and-gas plume that rose 1 km. The monitoring network did not record eruptive events during 11-12 March. Sulfur dioxide emissions fluctuated; emissions detected in satellite data averaged 344 tons per day (t/d) on 11 March and 472 t/d on 12 March and relatively high concentrations were measured by a gas sensor located at the Visitor Observation Deck on 12 March. Residents in Grecia (16 km SW), Sarchà (18 km SW), and San Gertrudis (13 km SSW) reported a sulfur odor and minor ashfall. A small phreatic eruption occurred at 0536 on 13 March, though continuous and voluminous emissions of steam and gas obscured views of the event. A sequence of small phreatic events was recorded during 1800-2000, culminating in a moderate phreatic eruption at 2000. A plume containing significant amounts of sulfur dioxide, hydrogen sulfide, and tephra drifted NW as far as the SW part of Nicaragua. Sulfur dioxide emissions detected in satellite data averaged 844 t/d. At 2300 instruments located at the visitor building of the Parque Nacional Volcán Poás recorded extreme levels of sulfur dioxide gas and particulates in the air; these conditions lasted until around 0300 on 14 March. During 0140-0200 on 14 March a gas monitoring station in San Isidro de Coronado measured high levels of sulfur dioxide gas from a plume that drifted S and E of the Valle Central. Residents of Heredia (28 km SE), Alajuela (21 km S), and San José (33 km SE) reported sulfur odors, minor ashfall, and adverse health effects like respiratory discomfort for both residents and animals. Gas-and-steam emissions continued from both Boca A and Boca C through 18 March. The Alert Level remained at 3 (the second highest level on a four-level scale) and the Aviation Color Code remained at Orange (the second highest color on a four-color scale). 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!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9x8Ch5McA$> Raung | Indonesia | 8.119°S, 114.056°E | Summit elev. 3260 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that a dense gray ash plume rose around 1.5 km above Raungâ??s summit crater rim and drifted W and NW at 0659 on 13 March. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater. Geologic Summary. Raung, one of Java's most active volcanoes, is a massive stratovolcano in easternmost Java that was constructed SW of the rim of Ijen caldera. The unvegetated summit is truncated by a dramatic steep-walled, 2-km-wide caldera that has been the site of frequent historical eruptions. A prehistoric collapse of Gunung Gadung on the W flank produced a large debris avalanche that traveled 79 km, reaching nearly to the Indian Ocean. Raung contains several centers constructed along a NE-SW line, with Gunung Suket and Gunung Gadung stratovolcanoes being located to the NE and W, respectively. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zAHd8AFw$> Turrialba | Costa Rica | 10.025°N, 83.767°W | Summit elev. 3340 m The Observatorio Vulcanológico y Sismológico de Costa Rica-Universidad Nacional (OVSICORI-UNA) reported that a small landslide in Turrialbaâ??s West Crater produced a small ash plume at 1545 on 14 March. Geologic Summary. Turrialba, the easternmost of Costa Rica's Holocene volcanoes, is a large vegetated basaltic-to-dacitic stratovolcano located across a broad saddle NE of Irazú volcano overlooking the city of Cartago. The massive edifice covers an area of 500 km2. Three well-defined craters occur at the upper SW end of a broad 800 x 2200 m summit depression that is breached to the NE. Most activity originated from the summit vent complex, but two pyroclastic cones are located on the SW flank. Five major explosive eruptions have occurred during the past 3500 years. A series of explosive eruptions during the 19th century were sometimes accompanied by pyroclastic flows. Fumarolic activity continues at the central and SW summit craters. 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!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9x8Ch5McA$> Ongoing Activity Ahyi | United States | 20.42°N, 145.03°E | Summit elev. -75 m Unrest at Ahyi Seamount continued during 7-14 March. A few hydroacoustic detections coming from the direction of Ahyi were identified in data from underwater pressure sensors near Wake Island (about 2,270 km E of Ahyi). Weather clouds obscured satellite views of the seamount. The Aviation Color Code remained at Yellow (the second lowest level on a four-color scale) and the Volcano Alert Level remained at Advisory (the second lowest level on a four-level scale). Geologic Summary. Ahyi seamount is a large conical submarine volcano that rises to within 75 m of the ocean surface ~18 km SE of the island of Farallon de Pajaros in the northern Marianas. Water discoloration has been observed there, and in 1979 the crew of a fishing boat felt shocks over the summit area, followed by upwelling of sulfur-bearing water. On 24-25 April 2001 an explosive eruption was detected seismically by a station on Rangiroa Atoll, Tuamotu Archipelago. The event was well constrained (+/- 15 km) at a location near the southern base of Ahyi. An eruption in April-May 2014 was detected by NOAA divers, hydroacoustic sensors, and seismic stations. Source: US Geological Survey https://www.usgs.gov/ <https://urldefense.com/v3/__https://www.usgs.gov/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9yzaP_JAg$> 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 March. Nightly crater incandescence was visible in webcam images during 10-14 March. An explosion at 1706 on 11 March generated an ash plume that rose 600 m straight up above the crater rim and merged into weather clouds. The explosion ejected large blocks 600-900 m from the vent. An eruptive event at 2027 on 13 March generated an ash plume that rose 1.2 km above the crater rim and drifted SW. An eruptive event at 1757 on 16 March generated an ash plume that rose 2.2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 1 km away from both the Minimadake and Showa 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!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9ymXbE_ig$> Bezymianny | Russia | 55.972°N, 160.595°E | Summit elev. 2882 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that a strong thermal anomaly over Bezymianny was identified in satellite images during 6-13 March. According to the Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS), incandescent debris avalanches descended the SE and/or E flanks and daily summit incandescence was visible during dark hours. The summit incandescence and debris avalanches were intense mid-week. Ash plumes generated from debris avalanches rose as high as 1.1 km above the summit and drifted mainly E, NE, and SE. Weather conditions occasionally obscured webcam and satellite views. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are reported in UTC; specific events are in local time where noted. Geologic Summary. The modern Bezymianny, much smaller than its massive neighbors Kamen and Kliuchevskoi on the Kamchatka Peninsula, was formed about 4,700 years ago over a late-Pleistocene lava-dome complex and an edifice built about 11,000-7,000 years ago. Three periods of intensified activity have occurred during the past 3,000 years. The latest period, which was preceded by a 1,000-year quiescence, began with the dramatic 1955-56 eruption. This eruption, similar to that of St. Helens in 1980, produced a large open crater that was formed by collapse of the summit and an associated lateral blast. Subsequent episodic but ongoing lava-dome growth, accompanied by intermittent explosive activity and pyroclastic flows, has largely filled the 1956 crater. Sources: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9z9SWoq9A$> ; Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS) http://www.kscnet.ru/ivs/ <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9xWiI9Row$> Dukono | Indonesia | 1.6992°N, 127.8783°E | Summit elev. 1273 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity at Dukono was high during 2025. The monitoring network recorded a range of 60-394 daily eruptive events (227 events/day average), with ash-and-gas plumes rising 200-2,500 m above the summit. Rumbling and booming sounds were reported during 12-13 March. Daily gas-and-ash plumes during 12-18 March generally rose up to 2.5 km above the summit and drifted NW, W, and SW. Plumes on 16 March rose higher; at 1346 and at 1442 dense gray ash plumes rose 3-3.1 km above the crater rim that drifted W and NW. The Alert Level remained at Level 2 (on a scale of 1-4) and the public was warned to stay 4 km away from the Malupang Warirang Crater. Geologic Summary. Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, have occurred since 1933. During a major eruption in 1550 CE, a lava flow filled in the strait between Halmahera and the N-flank Gunung Mamuya cone. This complex volcano presents a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also been active during historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zAHd8AFw$> Etna | Italy | 37.748°N, 14.999°E | Summit elev. 3357 m The Sezione di Catania - Osservatorio Etneo (INGV) reported continuing activity at Etna during 10-16 March. Weather clouds often obscured views of the summit area, though during a few clear periods gas emissions were observed rising from the summit craters. Strombolian activity at SE Crater resumed at 2018 on 15 March with incandescent ejecta staying inside the crater. The Aviation Color Code was raised to Yellow (the second lowest level on a four-color scale) at 2032 and then to Orange at 2047. Activity intensified at around 0000 on 16 March and incandescent material fell onto the flanks as far as the base of the crater. The activity peaked at 0115, began declining at 0215, and ceased at 0320. The Aviation Color Code was lowered to Yellow and then Green at 0841 and 1642, respectively, on 17 March. 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. Source: Sezione di Catania - Osservatorio Etneo (INGV) http://www.ct.ingv.it/ <https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9xZ35Y0nQ$> Great Sitkin | United States | 52.076°N, 176.13°W | Summit elev. 1740 m The Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick flow in Great Sitkinâ??s summit crater during 12-18 March. Small daily earthquakes were detected by the seismic network. Weather clouds often obscured satellite and webcam views of the volcano. Satellite images showed steaming at the lava flow during 16-17 March and lava advancement to the NE and E during 16-18 March. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale). Geologic Summary. The Great Sitkin volcano forms much of the northern side of Great Sitkin Island. A younger volcano capped by a small, 0.8 x 1.2 km ice-filled summit caldera was constructed within a large late-Pleistocene or early Holocene scarp formed by massive edifice failure that truncated an older edifice and produced a submarine debris avalanche. Deposits from this and an even older debris avalanche from a source to the south cover a broad area of the ocean floor north of the volcano. The summit lies along the eastern rim of the younger collapse scarp. Deposits from an earlier caldera-forming eruption of unknown age cover the flanks of the island to a depth up to 6 m. The small younger caldera was partially filled by lava domes emplaced in 1945 and 1974, and five small older flank lava domes, two of which lie on the coastline, were constructed along northwest- and NNW-trending lines. Hot springs, mud pots, and fumaroles occur near the head of Big Fox Creek, south of the volcano. Eruptions have been recorded since the late-19th century. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://avo.alaska.edu/ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9w_1Hm-DQ$> 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 March. Multiple daily dense gray ash plumes rose as high as 1.2 km above the summit and drifted in multiple directions. Very minor incandescence at the summit was visible in a few 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!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zAHd8AFw$> Kanlaon | Philippines | 10.4096°N, 123.13°E | Summit elev. 2422 m The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing eruptive activity at Kanlaon during 11-17 March. The seismic network recorded 6-21 daily volcanic earthquakes. Average daily sulfur dioxide emissions ranged from 1,712 to 4,065 tonnes per day. Gas-and-steam emissions that were often continuous and occasionally contained ash rose as high as 200 m above the summit and drifted W and SW. A period of ash emissions during 1526-1624 on 12 March produced grayish plumes that rose 50 m above the crater rim and drifted SW. The Alert Level remained at 3 (on a scale of 0-5); the public was warned to stay 6 km away from the summit and pilots were warned not to fly close to the volcano. Geologic Summary. Kanlaon volcano (also spelled Canlaon) forms the highest point on the Philippine island of Negros. The massive andesitic stratovolcano is covered with fissure-controlled pyroclastic cones and craters, many of which are filled by lakes. The largest debris avalanche known in the Philippines traveled 33 km SW from Kanlaon. The summit contains a 2-km-wide, elongated northern caldera with a crater lake and a smaller but higher active vent, Lugud crater, to the south. Eruptions recorded since 1866 have typically consisted of phreatic explosions of small-to-moderate size that produce minor local ashfall. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS) http://www.phivolcs.dost.gov.ph/ <https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9xf79djzg$> 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 March. Thermal anomalies over the volcano were identified in satellite images during 6, 9, and 11-13 March; 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!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9z9SWoq9A$> Katmai | United States | 58.279°N, 154.9533°W | Summit elev. 2047 m The Alaska Volcano Observatory (AVO) reported that on 16 March strong winds in the vicinity of Katmai and the Valley of Ten Thousand Smokes dispersed unconsolidated ash up to 1.8 km (6,000 ft) a.s.l. to the SE. The ash was originally deposited during the Novarupta-Katmai eruption in 1912. The Volcano Alert Level remained at Normal (the lowest level on a four-level scale) and the Aviation Color Code remained at Green (the lowest level on a four-color scale). Geologic Summary. Katmai was initially considered to be the source of the Valley of Ten Thousand Smokes ash flow in 1912. However, the 3 x 4 km caldera of 1912 is now known to have formed as a result of the voluminous eruption at nearby Novarupta volcano. The edifice had four NE-SW-trending summits, most of which were truncated by the 1912 collapse. Two or more large explosive eruptions took place during the late Pleistocene. Most of the two overlapping pre-1912 Katmai volcanoes are Pleistocene, but Holocene lava flows from a flank vent descend the SE flank of the SW edifice into the Katmai River canyon. The steep walled young caldera has a jagged rim that rises 500-1,000 m above the caldera floor and contains a deep lake. Lake waters have covered a small post-collapse lava dome (Horseshoe Island) that was seen on the caldera floor at the time of the initial ascent to the caldera rim in 1916. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://avo.alaska.edu/ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9w_1Hm-DQ$> 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 March. Small, sporadic, spatter fountains began at the N vent at about 0130 on 10 March and continued into 11 March. Lava flows emerged from the N vent at 0236 on 11 March and tall fountaining started 10 minutes later; by 0330 the fountains had reached 120-150 m and by 0400 they were over 180 m tall. Lava effusion at the S vent began at 0312 and fountaining began at 0330. Lava fountains from both vents continued through the day, rising 140-160 m. Sulfur dioxide emission averaged approximately 40,000 tonnes per day (t/d) during the period of high fountaining and Peleâ??s Hair was reported in Pahala, 40 km SW. Fountaining ceased at 1511 at the N vent and at 1513 at the S vent. Lava flows covered more than two-thirds of the crater floor. By 1700 sulfur dioxide emissions had decreased to an average of 3,000 t/d. Gas emissions and incandescence from both vents were visible during 12-18 March. Lava flows unrelated to activity at the N and S vents continue to spread across the down-dropped block on the E side of Halemaâ??umaâ??u, likely fed by magma previously intruded beneath the crater floor. 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!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9x68zP9GQ$> Lewotobi | Indonesia | 8.542°S, 122.775°E | Summit elev. 1703 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity continued at Lewotobi Laki-laki during 12-18 March. Daily eruptive events produced gray ash plumes that rose as high as 2.5 km above the summit and drifted NE, N, NW, and W. According to a news article 1,841 people had not returned home since evacuating in November 2024 and were distributed across relatives' houses, rental houses, and government-provided field evacuation posts or temporary housing. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 5 km away from the center of Laki-laki and 6 km in a semicircle clockwise from the SW to the NE. Geologic Summary. The Lewotobi edifice in eastern Flores Island is composed of the two adjacent Lewotobi Laki-laki and Lewotobi Perempuan stratovolcanoes (the "husband and wife"). Their summits are less than 2 km apart along a NW-SE line. The conical Laki-laki to the NW has been frequently active during the 19th and 20th centuries, while the taller and broader Perempuan has had observed eruptions in 1921 and 1935. Small lava domes have grown during the 20th century in both of the summit craters, which are open to the north. A prominent cone, Iliwokar, occurs on the E flank of Perampuan. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zAHd8AFw$> ; Antara News https://www.antaranews.com/berita/4714945/bnpb-pengungsi-gunung-lewotobi-berkurang-kini-masih-ada-1841-jiwa <https://urldefense.com/v3/__https://www.antaranews.com/berita/4714945/bnpb-pengungsi-gunung-lewotobi-berkurang-kini-masih-ada-1841-jiwa__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9x0qOTmfA$> Marapi | Indonesia | 0.38°S, 100.474°E | Summit elev. 2885 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Marapi (on Sumatra) continued during 12-18 March. White plumes generally rose as high as 300 m above the summit and drifted in multiple directions on most days. An eruptive event was recorded at 0755 on 13 March but not visually observed due to weather conditions. At 0700 on 16 March and at 1120 on 17 March dense gray ash plumes rose 800 m and 600 m above the summit and drifted N and NW, respectively. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the active crater. Geologic Summary. Gunung Marapi, not to be confused with the better-known Merapi volcano on Java, is Sumatra's most active volcano. This massive complex stratovolcano rises 2,000 m above the Bukittinggi Plain in the Padang Highlands. A broad summit contains multiple partially overlapping summit craters constructed within the small 1.4-km-wide Bancah caldera. The summit craters are located along an ENE-WSW line, with volcanism migrating to the west. More than 50 eruptions, typically consisting of small-to-moderate explosive activity, have been recorded since the end of the 18th century; no lava flows outside the summit craters have been reported in historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zAHd8AFw$> 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 March. Seismicity remained at high levels. The SW lava dome produced 54 lava avalanches that traveled as far as 2 km SW down the Bebeng drainage, 33 that traveled as far as 2 km SW down the Krasak drainage, and 31 that traveled as far as 2 km W down the Sat/Putih drainage. Slight morphological changes to the SW lava dome resulted from minor collapses of material. The hottest temperature was 248.5 degrees Celsius, and the volume was an estimated 3,626,200 cubic meters, based on webcam images and an 11 March drone survey. 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!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zLWa_PTg$> Reventador | Ecuador | 0.077°S, 77.656°W | Summit elev. 3562 m The Instituto GeofÃsico-Escuela Politécnica Nacional (IG-EPN) reported that eruptive activity continued at Reventador during 11-18 March. Seismicity included 59-106 daily explosions, long-period earthquakes, harmonic tremor, and tremor associated with emissions. Multiple daily ash-and-gas plumes rose as high as 1.1 km above the crater rim and drifted in multiple directions. Webcams recorded multiple instances nightly of incandescent material descending the flanks as far as 900 m below the crater rim. Minor ashfall was reported in Piedra Fina, 8 km SE, at around 0700 on 14 March; ashfall in that area had been persistent for the past few months. On 17 March a pyroclastic flow traveled 400 m down the SE flank. Incandescent material was ejected 400 m above the crater rim. SecretarÃa de Gestión de Riesgos maintained the Alert Level at Orange (the second highest level on a four-color scale). Geologic Summary. Volcán El Reventador is the most frequently active of a chain of Ecuadorian volcanoes in the Cordillera Real, well east of the principal volcanic axis. The forested, dominantly andesitic stratovolcano has 4-km-wide avalanche scarp open to the E formed by edifice collapse. A young, unvegetated, cone rises from the amphitheater floor to a height comparable to the rim. It has been the source of numerous lava flows as well as explosive eruptions visible from Quito, about 90 km ESE. Frequent lahars in this region of heavy rainfall have left extensive deposits on the scarp slope. The largest recorded eruption took place in 2002, producing a 17-km-high eruption column, pyroclastic flows that traveled up to 8 km, and lava flows from summit and flank vents. Sources: Instituto GeofÃsico-Escuela Politécnica Nacional (IG-EPN) http://www.igepn.edu.ec/ <https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9w_7ie_2Q$> ; SecretarÃa de Gestión de Riesgos (SGR) http://www.gestionderiesgos.gob.ec/ <https://urldefense.com/v3/__http://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9wRc6eqiw$> Rincon de la Vieja | Costa Rica | 10.83°N, 85.324°W | Summit elev. 1916 m The Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) reported that occasional, small, phreatic eruptions at Rincón de la Vieja were recorded during 12-17 March in monitoring network data. A phreatic eruption at 1828 on 13 March was preceded by more than 25 tornillo-type seismic events. A phreatic event at 0344 on 14 March was the most energetic so far in 2025 and produced a voluminous steam-and-gas plume with tephra that drifted SW. Geologic Summary. Rincón de la Vieja, the largest volcano in NW Costa Rica, is a remote volcanic complex in the Guanacaste Range. The volcano consists of an elongated, arcuate NW-SE-trending ridge constructed within the 15-km-wide early Pleistocene GuachipelÃn caldera, whose rim is exposed on the south side. Sometimes known as the "Colossus of Guanacaste," it has an estimated volume of 130 km3 and contains at least nine major eruptive centers. Activity has migrated to the SE, where the youngest-looking craters are located. The twin cone of Santa MarÃa volcano, the highest peak of the complex, is located at the eastern end of a smaller, 5-km-wide caldera and has a 500-m-wide crater. A Plinian eruption producing the 0.25 km3 RÃo Blanca tephra about 3,500 years ago was the last major magmatic eruption. All subsequent eruptions, including numerous historical eruptions possibly dating back to the 16th century, have been from the prominent active crater containing a 500-m-wide acid lake located ENE of Von Seebach crater. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) http://www.ovsicori.una.ac.cr/ <https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9x8Ch5McA$> Sangay | Ecuador | 2.005°S, 78.341°W | Summit elev. 5286 m The Instituto GeofÃsico-Escuela Politécnica Nacional (IG-EPN) reported that moderate levels of eruptive activity continued at Sangay during 11-18 March. The seismic network recorded 78-475 daily explosions. Weather clouds obscured views most of the week, but during 16-17 March several gas-and-ash plumes were visible rising as high as 1 km above the summit and drifting W, WSW, and SW. SecretarÃa de Gestión de Riesgos (SGR) maintained the Alert Level at Yellow (the second highest level on a four-color scale). Geologic Summary. The isolated Sangay volcano, located east of the Andean crest, is the southernmost of Ecuador's volcanoes and its most active. The steep-sided, glacier-covered, dominantly andesitic volcano grew within the open calderas of two previous edifices which were destroyed by collapse to the east, producing large debris avalanches that reached the Amazonian lowlands. The modern edifice dates back to at least 14,000 years ago. It towers above the tropical jungle on the east side; on the other sides flat plains of ash have been eroded by heavy rains into steep-walled canyons up to 600 m deep. The earliest report of an eruption was in 1628. Almost continuous eruptions were reported from 1728 until 1916, and again from 1934 to the present. The almost constant activity has caused frequent changes to the morphology of the summit crater complex. Sources: Instituto GeofÃsico-Escuela Politécnica Nacional (IG-EPN) http://www.igepn.edu.ec/ <https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9w_7ie_2Q$> ; SecretarÃa de Gestión de Riesgos (SGR) http://www.gestionderiesgos.gob.ec/ <https://urldefense.com/v3/__http://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9wRc6eqiw$> Santa Maria | Guatemala | 14.757°N, 91.552°W | Summit elev. 3745 m The Instituto Nacional de SismologÃa, VulcanologÃa, MeteorologÃa e HidrologÃa (INSIVUMEH) reported ongoing, high-level eruptive activity at Santa Mariaâ??s Santiaguito dome complex during 11-18 March with continuing lava extrusion at Caliente dome. Daily explosions, as many as seven per hour when reported, generated gas-and-ash plumes that rose as high as 1.2 km above the dome and possibly drifted as far as 40 km S, SW, W, and NE. Effusion of blocky lava and collapses of material produced block avalanches that were sometimes heard several kilometers away; these mainly descended the SW and S flanks. Collapsed material sometimes produced short pyroclastic flows that descended the flanks in all directions. Incandescence was visible at the crater and upper part of the SW flank lava flow. Ashfall was forecast for areas downwind on most days. Geologic Summary. Symmetrical, forest-covered Santa MarÃa volcano is part of a chain of large stratovolcanoes that rise above the Pacific coastal plain of Guatemala. The sharp-topped, conical profile is cut on the SW flank by a 1.5-km-wide crater. The oval-shaped crater extends from just below the summit to the lower flank, and was formed during a catastrophic eruption in 1902. The renowned Plinian eruption of 1902 that devastated much of SW Guatemala followed a long repose period after construction of the large basaltic andesite stratovolcano. The massive 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 vents, with activity progressing E towards the most recent, Caliente. Dome growth has been accompanied by almost continuous minor explosions, with periodic lava extrusion, larger explosions, pyroclastic flows, and lahars. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) http://www.insivumeh.gob.gt/ <https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zMh1nQmw$> Semeru | Indonesia | 8.108°S, 112.922°E | Summit elev. 3657 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 12-18 March, with multiple, daily eruptive events recorded by the seismic network. Daily white-and-gray or gray ash plumes rose 500-1,200 m above the summit and drifted in multiple directions. The Alert Level remained at 2 (the second lowest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards. Geologic Summary. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9zAHd8AFw$> 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 March. 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!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9z9SWoq9A$> Spurr | United States | 61.299°N, 152.251°W | Summit elev. 3374 m The Alaska Volcano Observatory (AVO) reported increasing unrest at Spurr in a special information statement issued on 12 March. Collapses of snow and ice into the summit crater lake that formed during the current period of unrest continued to occur along with steam emissions from fumaroles within and around the summit crater. New diffuse steam plumes from small snow-free spots within Crater Peak, a vent 3.5 km S of the summit, were first observed on 6 March. These locations have been sporadically snow-free for years, but steaming had not been observed since 2008. Significantly elevated volcanic gas emissions were measured during overflights on 7 and 11 March, when newly reactivated fumaroles at Crater Peak were also observed. About 450 tons per day (t/d) of sulfur dioxide at the summit crater was measured on 7 March, an increase from less than 50 t/d measured in December 2024. Notably high concentrations of carbon dioxide detected at Crater Peak are similar to values measured before other eruptions such as Redoubt in 2009. An average of 100 earthquakes per week were located during the past month; most were shallow, around 4 km below sea level, with the largest being M 2.7. Over 3,400 earthquakes had been located since April 2024. Ground deformation continued to be detected with a total of about 6.5 cm of inflation recorded at the closest Global Navigation Satellite System (GNSS) station. Modeling of the data suggested that the source was located 3-5 km below sea level and 3-4 km W of the summit. Seismicity remained elevated during 13-18 March with numerous small, shallow volcanic earthquakes detected beneath the volcano. Weather clouds often obscured views, though the crater lake and a gas plume were visible on 15 March, and a small steam plume rising from the summit was observed in clear webcam and satellite images during 17-18 March. The interpretation from AVO is that a magmatic intrusion has been underway for months, and the recent gas data suggests that a new pathway towards the Crater Peak vent has opened; Crater Peak erupted in 1953 and 1992 and the summit last erupted several thousand years ago. The Volcano Alert Level remained at Advisory (the second lowest level on a four-level scale) and the Aviation Color Code remained at Yellow (the second lowest level on a four-color scale). Geologic Summary. Mount Spurr is the closest volcano to Anchorage, Alaska (130 km W) and just NE of Chakachamna Lake. The summit is a large lava dome at the center of a roughly 5-km-wide amphitheater open to the south formed by a late-Pleistocene or early Holocene debris avalanche and associated pyroclastic flows that destroyed an older edifice. The debris avalanche traveled more than 25 km SE, and the resulting deposit contains blocks as large as 100 m in diameter. Several ice-carved post-collapse cones or lava domes are present. The youngest vent, Crater Peak, formed at the southern end of the amphitheater and has been the source of about 40 identified Holocene tephra layers. Eruptions from Crater Peak in 1953 and 1992 deposited ash in Anchorage. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://avo.alaska.edu/ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9w_1Hm-DQ$> Stromboli | Italy | 38.789°N, 15.213°E | Summit elev. 924 m The Sezione di Catania - Osservatorio Etneo (INGV) reported that eruptive activity continued at Stromboli during 10-16 March. Webcam images showed Strombolian activity at four vents in Area N within the upper part of the Sciara del Fuoco and from at least two vents in Area C-S (South-Central Crater) on the crater terrace. The vents in Area N continued to produce low- to medium-intensity explosions at a rate of 4-9 events per hour, ejecting lapilli and bombs less than 150 m above the vents. Explosions at the vents in Area C-S ejected tephra above the vent at a rate of 1-4 events per hour. The Alert Level remained at Yellow (the second lowest level on a four-level scale). Geologic Summary. Spectacular incandescent nighttime explosions at Stromboli have long attracted visitors to the "Lighthouse of the Mediterranean" in the NE Aeolian Islands. This volcano has lent its name to the frequent mild explosive activity that has characterized its eruptions throughout much of historical time. The small island is the emergent summit of a volcano that grew in two main eruptive cycles, the last of which formed the western portion of the island. The Neostromboli eruptive period took place between about 13,000 and 5,000 years ago. The active summit vents are located at the head of the Sciara del Fuoco, a prominent scarp that formed about 5,000 years ago due to a series of slope failures which extends to below sea level. The modern volcano has been constructed within this scarp, which funnels pyroclastic ejecta and lava flows to the NW. Essentially continuous mild Strombolian explosions, sometimes accompanied by lava flows, have been recorded for more than a millennium. Source: Sezione di Catania - Osservatorio Etneo (INGV) http://www.ct.ingv.it/ <https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9xZ35Y0nQ$> Suwanosejima | Japan | 29.638°N, 129.714°E | Summit elev. 796 m The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 10-17 March. Incandescence was observed nightly in webcam images. Eruptive activity generated emissions that rose 900 m above the crater rim. The Alert Level remained at 2 (the second level on a five-level scale) and the public was warned to stay at least 1.5 km away from the crater. Geologic Summary. The 8-km-long island of Suwanosejima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two active summit craters. The summit is truncated by a large breached crater extending to the sea on the E flank that was formed by edifice collapse. One of Japan's most frequently active volcanoes, it was in a state of intermittent Strombolian activity from Otake, the NE summit crater, between 1949 and 1996, after which periods of inactivity lengthened. The largest recorded eruption took place in 1813-14, when thick scoria deposits covered residential areas, and the SW crater produced two lava flows that reached the western coast. At the end of the eruption the summit of Otake collapsed, forming a large debris avalanche and creating an open collapse scarp extending to the eastern coast. The island remained uninhabited for about 70 years after the 1813-1814 eruption. Lava flows reached the eastern coast of the island in 1884. Only about 50 people live on the island. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!eiURdre6N0Y55olCL32W73esrXhP43iWAHdt6fI0-N_ogjvUw-PxuElptRTwrcoHe3IM0i84hrERDMYTC9ymXbE_ig$> 2-2-2-2-2-2-2-2-2-2-2-2-2 ============================================================== 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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