3-3-3-3-3-3-3-3-3-3-3-3-3 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 14-20 May 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CSLLONJ2w$> New Activity/Unrest: Bezymianny, Russia | Kanlaon, Philippines | Klyuchevskoy, Russia | Lewotobi, Indonesia | Raung, Indonesia Ongoing Activity: Aira, Japan | Dukono, Indonesia | Etna, Italy | Great Sitkin, United States | Ibu, Indonesia | Karymsky, Russia | Kilauea, United States | Lewotolok, Indonesia | Manam, Papua New Guinea | Marapi, Indonesia | Merapi, Indonesia | Nevado del Ruiz, Colombia | Ontakesan, Japan | Poas, Costa Rica | Reventador, Ecuador | Sangay, Ecuador | Semeru, Indonesia | Sheveluch, Russia | 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 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 8-15 May. According to the Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS), crater incandescence was visible during dark hours on some days when weather clouds did not obscure views. Hot avalanches of material descended the flanks on 12 May. The Aviation Color Code remained at Yellow (the second lowest 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CQ6wyEKig$> ; 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CShoEjKZQ$> Kanlaon | Philippines | 10.4096°N, 123.13°E | Summit elev. 2422 m The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported that the five-minute eruption at Kanlaon on 13 May consisted of two successive ejections of incandescent material and an ash plume that rose possibly as high as 8 km above the crater rim; pyroclastic density currents descended the S flanks as far as 2 km. Ashfall impacted a total of 51 barangays in nine municipalities (four provinces). Sulfur dioxide emissions averaged 5,241 tonnes per day (t/d) that day. Satellite analysis indicated extensive drift of sulfur dioxide across the Philippines, Palawan Island, and N Borneo. Activity continued during 14-20 May. Gas-and-steam plumes with occasional ash content drifted W and SW on 14 May. Diffuse gas-and-steam plumes rose as high as 100 m above the summit and drifted NW, W, and SW during the rest of the week. The seismic network recorded 2-16 daily volcanic earthquakes. Daily sulfur dioxide emissions ranged from 852 to 2,533 tonnes per day. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CR_OubL1w$> Klyuchevskoy | Russia | 56.056°N, 160.642°E | Summit elev. 4754 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that a thermal anomaly at Klyuchevskoy was periodically identified in satellite images during 8-15 May. The Aviation Color Code remained at Yellow (the second lowest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. Klyuchevskoy is the highest and most active volcano on the Kamchatka Peninsula. Since its origin about 6,000 years ago, this symmetrical, basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. It rises above a saddle NE of Kamen volcano and lies SE of the broad Ushkovsky massif. More than 100 flank eruptions have occurred during approximately the past 3,000 years, with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks of the conical volcano between 500 and 3,600 m elevation. Eruptions recorded since the late 17th century have resulted in frequent changes to the morphology of the 700-m-wide summit crater. These eruptions over the past 400 years have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CQ6wyEKig$> Lewotobi | Indonesia | 8.542°S, 122.775°E | Summit elev. 1703 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Lewotobi Laki-laki continued during 12-20 May, with a larger eruption on 18 May. White steam-and-gas plumes rose 50-800 m above the crater rim and drifted in various directions during 14 and 16-17 May. White-and-gray plumes rose as high as 300 m above the summit and drifted SW and W on 15 May. At 0120 on 18 May a gray ash plume rose 900 m above the summit and drifted SW and S. A period of continuous ash, steam, and gas emissions began at around 1149 on 18 May with a dense gray ash plume that rose 800 m above the summit and drifted N. Dense ash emissions continued through the day and rumbling and banging was heard at the nearest observation post. The ash plume rose to 2 km by 1209 and 3 km by 1218, drifting N and NE. During 1246-1323 the ash plume was as high as 3.5 km above the summit and began drifting also NW. By 1405 the plume had risen to 6 km above the summit and expanded NE, N, NW, W, and SW. The plume was lower at 1430, rising to 4 km and drifting N, NW, and W. Hazy conditions due to ash in the air, possibly mixed with weather clouds based on webcam views prevented visual observations at 1527 and 1614. A dense ash plume rose to 2 km above the summit and drifted NW at 1637. At 2000 PVMBG raised the Alert Level to 4 (on a scale of 1-4). The public was warned to stay 6 km away from the center of Laki-laki and 7 km in a semicircle clockwise from the W to the NE. At 0008 on 19 May a dense gray ash plume rose 1.2 km above the summit and drifted N and NE. Eruptive events were recorded at 0936, at 1248, at 1342, and at 1406, though conditions prevented visual observations. Ash emissions were ongoing during 1437-2149 with ash plumes rising as high as 5 km above the summit and fanning out from the E counterclockwise to the W. Webcam images at 2145 and 2150 showed incandescent material on the upper flanks and at the summit. Ash plumes rose 4 km above the summit at 2152, 1 km above the summit at 2217, and 500 m above the summit at 2315 and drifted W and NW. Incandescence at the summit was visible in corresponding webcam images. Ash plumes rose 500 m and 300 m above the summit at 0209 and 0224, respectively, on 20 May. Incandescence was again visible at the summit in corresponding webcam images. 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. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CReBTarDA$> Raung | Indonesia | 8.119°S, 114.056°E | Summit elev. 3260 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported increasing volcanic activity at Raung on 16 May. At 0551 an observer saw an ash plume rise to around 1,250 m above the summit and drift S to SW. According to the Darwin VAAC the plume had dissipated by 1140 that same day. 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. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CReBTarDA$> ; Darwin Volcanic Ash Advisory Centre (VAAC) http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml <https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CSCewjerA$> Ongoing Activity 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). No eruptive events were recorded during 5-15 May, though inflation continued to be detected in deformation data, notably starting at 2000 on 12 May. Sulfur dioxide emissions were slightly low, averaging 300 tons per day (t/d); the last measurement was 900 t/d on 2 May. Continuous eruptive activity, including seven explosions, began at around 1045 on 15 May and ended at around 0400 on 16 May, producing ash plumes that rose as high has 3 km above the summit and drifted in multiple directions. Large blocks were ejected as far as 1.2 km from the vent. Field observations confirmed notable ashfall on the E part of the island on 15 May and the N side of the island on 16 May. Deformation data showed a period of deflation after explosions on 15 May, then inflation resumed. Eruptive activity occurred intermittently during 16 May through at least 1500 on 19 May; 86 eruptive events and 44 explosions were detected, generating ash plumes that generally rose as high as 2.9 km above the crater and ejecting blocks as far as 900 m from the crater rim. An ash plume from an explosion at 1854 on 18 May rose 3.2 km above the crater rim and rifted SE, and large blocks were ejected as far as 1.2 km from the crater rim. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to be cautious within 2 km of 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CS_kZB5gw$> Dukono | Indonesia | 1.6992°N, 127.8783°E | Summit elev. 1273 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Dukono continued during 14-20 May. Daily white-and-gray or white, gray, and black gas-and-ash plumes rose 600-1,500 m above the summit and drifted N, NE, E, and SE. The emissions were continuous most of the day on 14 May, during approximately 0517-1703 on 15 May, from about 0803 on 16 May to about 2217 on 19 May, and during the morning of 20 May. The Alert Level remained at Level 2 (on a scale of 1-4) and the public was warned to stay 4 km away from the Malupang Warirang Crater. Geologic Summary. The Dukono complex in northern Halmahera is on an edifice with a broad, low profile containing multiple peaks and overlapping craters. Almost continuous explosive eruptions, sometimes accompanied by lava flows, have occurred since 1933. During a major eruption in 1550 CE, a lava flow filled in the strait between Halmahera and the Gunung Mamuya cone, 10 km NE. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also had reported eruptions. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CReBTarDA$> Etna | Italy | 37.748°N, 14.999°E | Summit elev. 3357 m The Sezione di Catania - Osservatorio Etneo (INGV) reported continuing eruptive activity at Etnaâ??s SE Crater and gas emissions at Bocca Nuova Crater, NE Crater, and Voragine during 12-18 May. Strombolian activity at SE Crater began in the late afternoon of 12 May, though weather clouds obscured visual observations. The activity was visually confirmed at 2030 during a break in the weather clouds. An eruption cloud drifted downwind and caused minor tephra fall along the SE flank reaching the towns of Petrulli and Zafferana Etnea. Two small lava flows descended the S and E flanks of SE Crater, as far as 0.8 km and 1.8 km, respectively. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CQYQBGCEg$> 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 14-20 May. Small daily earthquakes were detected by the seismic network. Weakly elevated surface temperatures consistent with lava effusion were observed in clear satellite views during 16-19 May and steaming from the active vent was observed during 17-18 May. Weather clouds sometimes obscured views of the volcano. A 20 May radar image confirmed that lava was slowly advancing NE. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CTWX29vOQ$> 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 14-20 May. Daily gray, white-to-gray, or white-to-brown ash plumes rose as high as 1 km above the summit and drifted in various directions. Nighttime crater incandescence was visible in some webcam images. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CReBTarDA$> Karymsky | Russia | 54.049°N, 159.443°E | Summit elev. 1513 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that, in general, moderate explosive activity continued at Karymsky during 8-15 May. Ash clouds were identified in satellite images drifting as far as 250 km SE and NE during 10-11 May. A thermal anomaly over the volcano was identified during 11-15 May; weather clouds obscured views on other days. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CQ6wyEKig$> 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 two vents along the SW margin of Halemaâ??umaâ??u Crater, continued at variable levels during 14-20 May. Incandescence at both the N and S vents was visible during 13-16 May, and occasional spattering at the N vent occurred during the evening of 14 May. Small, sporadic, â??gas-pistonâ?? events that produced spatter fountains and short lava flows began at the N vent at 2245 on 15 May. Five more â??gas-pistonâ?? events and lava flows occurred the next morning at 0030, 0100, 0125, 0154, and 0243 on 16 May. Dome fountains overflowed the crater at 0440, and sustained high fountaining began at 0513. Fountain heights peaked at 300 m around 0600, then began to oscillate between 100 and 150 m. By 0610 the fountains were producing multiple lava flows that covered about 30-40 percent of the crater floor. The gas plume rose as high as 3 km and drifted WSW, away from populated areas. Sulfur dioxide emission rates were expected to be similar to those recorded during other moderate-to-high fountaining episodes, or around 50,000 tonnes per day (t/d). After over 10 hours of high fountains, that activity ceased at 1529 after an estimated 3.8 million cubic meters of lava had been erupted. Incandescence from the lava flows was visible near the active vent region and along the N margin of the crater floor overnight during 16-17 May, and incandescence at both the N and S vents was visible during 16-20 May. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CQjuBKwsA$> Lewotolok | Indonesia | 8.274°S, 123.508°E | Summit elev. 1431 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that an eruption at Lewotolok was ongoing during 14-20 May. Daily white steam-and-gas plumes rose as high as 100 m above the summit of the cone and drifted NW and W. A nighttime webcam image on 15 May showed incandescence at the summit. At 0751 on 19 May a gray ash plume rose around 500 m above the summit and drifted NW. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 2 km away from the vent and 2.5 km away on the S, SE, and W flanks. Geologic Summary. The Lewotolok (or Lewotolo) stratovolcano occupies the eastern end of an elongated peninsula extending north into the Flores Sea, connected to Lembata (formerly Lomblen) Island by a narrow isthmus. It is symmetrical when viewed from the north and east. A small cone with a 130-m-wide crater constructed at the SE side of a larger crater forms the volcano's high point. Many lava flows have reached the coastline. Eruptions recorded since 1660 have consisted of explosive activity from the summit crater. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CReBTarDA$> 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 1020 on 16 May drifting SE. The plume had dissipated by 1220. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CSCewjerA$> Marapi | Indonesia | 0.38°S, 100.474°E | Summit elev. 2885 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity from Verbeek Crater at Marapi (on Sumatra) continued during 14-20 May, characterized by occasional dense gray ash plumes. The tallest ash plume rose 1.6 km above the crater rim at 0942 on 14 May and drifted NE. At 1939 on 15 May an ash plume rose 800 m and drifted E. Ash plumes at 0947 and 0954 on 17 May rose 1 km and 600 m above the crater rim, respectively, and drifted N and NE. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the active crater. Geologic Summary. Gunung Marapi, not to be confused with the better-known Merapi volcano on Java, is Sumatra's most active volcano. This massive complex stratovolcano rises 2,000 m above the Bukittinggi Plain in the Padang Highlands. A broad summit contains multiple partially overlapping summit craters constructed within the small 1.4-km-wide Bancah caldera. The summit craters are located along an ENE-WSW line, with volcanism migrating to the west. More than 50 eruptions, typically consisting of small-to-moderate explosive activity, have been recorded since the end of the 18th century; no lava flows outside the summit craters have been reported in historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CReBTarDA$> 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 9-15 May. Seismicity remained at high levels. The SW lava dome produced 43 lava avalanches that traveled as far as 2 km SW down the Bebeng drainage, 18 that traveled as far as 2 km SW down the Krasak drainage, and 32 that traveled as far as 2 km W down the Sat/Putih drainage. Small morphological changes to the SW lava dome resulted from continuing effusion and minor collapses of material. The hottest temperature was 247.4 degrees Celsius, and the volume of the dome increased by 71,200 cubic meters to an estimated 3,996,800 cubic meters, based on webcam images and a 12 May drone survey. The size of the central dome had not changed; the highest temperature decreased three degrees to 218 degrees Celsius. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CTSSmkg2A$> Nevado del Ruiz | Colombia | 4.892°N, 75.324°W | Summit elev. 5279 m The Servicio Geológico Colombianoâ??s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that eruptive activity at Nevado del Ruiz continued during 13-19 May. Seismic data indicated that events associated with fluid movement decreased in both number and intensity compared to the previous week. Seismicity associated with rock fracturing increased in both number and intensity compared to the previous week. The earthquakes were mainly located below Arenas Crater and the NE and SW flanks within 12 km at depths of 1-7 km. Seismicity indicating growth of the lava dome remained at low levels. Low-energy thermal anomalies on the crater floor were identified in satellite data, though weather clouds often obscured views. Significant sulfur dioxide emissions continued to be detected in satellite data. Gas-and-steam plumes rose as high as 500 m above the summit and drifted NW, WNW, and W. The only confirmed gas-and-ash plume during the week rose 700 m above the summit at 0837 on 17 May. The Alert Level remained at Yellow (the second level on a four-level scale). Geologic Summary. Nevado del Ruiz is a broad, glacier-covered volcano in central Colombia that covers more than 200 km2. Three major edifices, composed of andesitic and dacitic lavas and andesitic pyroclastics, have been constructed since the beginning of the Pleistocene. The modern cone consists of a broad cluster of lava domes built within the caldera of an older edifice. The 1-km-wide, 240-m-deep Arenas crater occupies the summit. The prominent La Olleta pyroclastic cone located on the SW flank may also have been active in historical time. Steep headwalls of massive landslides cut the flanks. Melting of its summit icecap during historical eruptions, which date back to the 16th century, has resulted in devastating lahars, including one in 1985 that was South America's deadliest eruption. Source: Servicio Geológico Colombiano (SGC) https://www2.sgc.gov.co/volcanes/index.html <https://urldefense.com/v3/__https://www2.sgc.gov.co/volcanes/index.html__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CSBD2cvzw$> Ontakesan | Japan | 35.893°N, 137.48°E | Summit elev. 3067 m Escalating seismicity coupled with minor inflation at Ontakesan in January caused the Japan Meteorological Agency (JMA) to raise the Alert Level to 2 (on a scale of 1-5). Beginning in February deformation stagnated and only a few volcanic earthquakes were recorded by the seismic network through 20 May. The Alert Level was lowered to 1 at 1100 on 20 May. Geologic Summary. The massive Ontakesan stratovolcano, the second highest volcano in Japan, lies at the southern end of the Northern Japan Alps. Ascending this volcano is one of the major objects of religious pilgrimage in central Japan. It is constructed within a largely buried 4 x 5 km caldera and occupies the southern end of the Norikura volcanic zone, which extends northward to Yakedake volcano. The older volcanic complex consisted of at least four major stratovolcanoes constructed from about 680,000 to about 420,000 years ago, after which Ontakesan was inactive for more than 300,000 years. The broad, elongated summit of the younger edifice is cut by a series of small explosion craters along a NNE-trending line. Several phreatic eruptions post-date the roughly 7300-year-old Akahoya tephra from Kikai caldera. The first historical eruption took place in 1979 from fissures near the summit. A non-eruptive landslide in 1984 produced a debris avalanche and lahar that swept down valleys south and east of the volcano. Very minor phreatic activity caused a dusting of ash near the summit in 1991 and 2007. A significant phreatic explosion in September 2014, when a large number of hikers were at or near the summit, resulted in many fatalities. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CS_kZB5gw$> 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 continuing gas-and-steam emissions that occasionally contained ash at Poás during 14-20 May. Activity generally decreased during the week, and deformation data indicated deflation. Vigorous gas-and-steam emissions continued at Boca A and incandescence was visible at night. Water that had pooled at Boca C continued to bubble; torrential rains during the beginning of the week continued to fill the crater. A moderate phreatic eruption at 0408 on 18 May generated a gas-and-steam plume with minor amounts of ash that rose 1 km above the crater rim and drifted SW. Sulfur dioxide emissions detected in satellite data were estimated to be 650 tons per day (t/d) on 18 May, 350 t/d on 19 May, and 598 t/d on 20 May. The volcanoâ??s 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CQvAiLjLg$> 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 13-20 May. Seismicity included 68-106 daily explosions, long-period earthquakes, harmonic tremor, and tremor associated with emissions. Multiple daily ash-and-gas plumes rose 200-2,000 m above the crater rim and drifted in multiple directions. Webcams recorded multiple nightly instances of incandescent material descending the flanks as far as 1.1 km below the crater rim, specifically down the ESE and SE flanks during 17-18 May. Weather clouds occasionally obscured views. SecretarÃa de Gestión de Riesgos (SGR) 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. Source: Instituto GeofÃsico-Escuela Politécnica Nacional (IG-EPN) http://www.igepn.edu.ec/ <https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CSYCe4_9g$> Sangay | Ecuador | 2.005°S, 78.341°W | Summit elev. 5286 m The Instituto GeofÃsico-Escuela Politécnica Nacional (IG-EPN) reported high levels of eruptive activity at Sangay during 13-20 May. The seismic network recorded 98-194 daily explosions. Ash-and-gas plumes were observed in webcam and/or satellite images on most days rising as high as 2 km above the summit and drifting in multiple directions. Weather clouds often obscured observations, especially during the first half of the week. Crater incandescence was sometimes visible during dark hours from 17 May through 20 May. Incandescent avalanches of material descended the SE flank 600 m during 18-19 May. SecretarÃa de Gestión de Riesgos (SGR) maintained the Alert Level at Yellow (the second highest level on a four-color scale). Geologic Summary. The isolated Sangay volcano, located east of the Andean crest, is the southernmost of Ecuador's volcanoes and its most active. The steep-sided, glacier-covered, dominantly andesitic volcano grew within the open calderas of two previous edifices which were destroyed by collapse to the east, producing large debris avalanches that reached the Amazonian lowlands. The modern edifice dates back to at least 14,000 years ago. It towers above the tropical jungle on the east side; on the other sides flat plains of ash have been eroded by heavy rains into steep-walled canyons up to 600 m deep. The earliest report of an eruption was in 1628. Almost continuous eruptions were reported from 1728 until 1916, and again from 1934 to the present. The almost constant activity has caused frequent changes to the morphology of the summit crater complex. Sources: Instituto GeofÃsico-Escuela Politécnica Nacional (IG-EPN) http://www.igepn.edu.ec/ <https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CSYCe4_9g$> ; SecretarÃa de Gestión de Riesgos (SGR) http://www.gestionderiesgos.gob.ec/ <https://urldefense.com/v3/__http://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CQxvjP80Q$> Semeru | Indonesia | 8.108°S, 112.922°E | Summit elev. 3657 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 14-20 May, with multiple daily eruptive events recorded by the seismic network. Daily white-and-gray or gray ash plumes rose 300-1,000 m above the summit and drifted in multiple directions. The Alert Level remained at 2 (the second lowest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards. Geologic Summary. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CReBTarDA$> Sheveluch | Russia | 56.653°N, 161.36°E | Summit elev. 3283 m The Kamchatkan Volcanic Eruption Response Team (KVERT) and the Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS) 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 8-15 May. Thermal anomalies over the domes were identified in satellite images almost daily; weather clouds sometimes obscured views. 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. 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CQ6wyEKig$> ; Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS) http://www.kscnet.ru/ivs/ <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/__;!!IKRxdwAv5BmarQ!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CShoEjKZQ$> 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 15-19 May. Incandescence was observed nightly in webcam images. No explosions were detected, though plumes from eruptive events rose 1 km above the crater rim. The Alert Level remained at 2 (the second level on a five-level scale) and the public was warned to be cautious within 1.5 km of 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!ZS4pc209PI0F1qIFXn-2ZcTSR3k6k_aDbIyijZ4vrXMi0r3rquFHOFVtVGAbg_XQtalTe9pqLpHJqoun2CS_kZB5gw$> 3-3-3-3-3-3-3-3-3-3-3-3-3 ============================================================== 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). ASU - http://www.asu.edu/ PSU - http://pdx.edu/ GVP - https://volcano.si.edu/ IAVCEI - https://www.iavceivolcano.org/ To subscribe to the volcano list, send the message: subscribe volcano to: listserv@xxxxxxx, or write to: volcano-request@xxxxxxx To unsubscribe from the volcano list, send the message: signoff volcano to: listserv@xxxxxxx, or write to: volcano-request@xxxxxxx. To contribute to the volcano list, send your message to: volcano@xxxxxxx. Please do not send attachments. ============================================================== ------------------------------ End of Volcano Digest - 19 May 2025 to 21 May 2025 (#2025-46) *************************************************************
