4-4-4-4-4-4-4-4-4-4-4-4-4 From: "Bennis, Kadie" <BennisK@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 9 April-15 April 2025 Kadie Bennis - Weekly Report Editor (bennisk@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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlg-Va0Ew$> New Activity/Unrest: Etna, Italy | Klyuchevskoy, Russia | Poas, Costa Rica Ongoing Activity: Ahyi, United States | Aira, Japan | Bezymianny, Russia | Dukono, Indonesia | Great Sitkin, United States | Ibu, Indonesia | Kanlaon, Philippines | Kilauea, United States | Lewotobi, Indonesia | Lewotolok, Indonesia | Marapi, Indonesia | Merapi, Indonesia | Popocatepetl, Mexico | Reventador, Ecuador | Sangay, Ecuador | Santa Maria, Guatemala | Semeru, Indonesia | Sheveluch, Russia | 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* *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 7-15 April. All the summit craters were characterized by degassing during the week and Strombolian activity was reported at SE Crater during 7-8, 11, and 15 April. At around 2300 on 7 April explosive activity produced a plume that drifted SE and resulted in ashfall in both Catania (29 km SSE) and Nicolosi (16 km S). At 0040 on 8 April a lava effusion began, with a flow descending the S flank. According to a Skysat image from 11 April, the lava flow covered an area of 14,000 m2, was 500 m long, and reached an elevation of 3 km (9,800 ft) a.s.l. Another Strombolian event began around 1400 on 11 April, though weather conditions prevented clear views of the summit. An active lava flow observed on the E flank around 2000 on 11 April had stopped by midnight. An ash plume during this time extended SE and resulted in light ashfall in Lavinaio, Acireale (20 km SE), and Aci San Antonio (18 km SE). By 12 April Strombolian activity was no longer observed. On 15 April Strombolian activity resumed at SE Crater, accompanied by moderate ash emissions, based on webcam images and INGV-OE personnel in the field. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYn9IuXbmg$> *Klyuchevskoy* | Russia | 56.056°N, 160.642°E | Summit elev. 4754 m The Tokyo VAAC reported ash plumes from Klyuchevskoy that rose to 6 km (19,700 ft) a.s.l. and drifted W at 1949 and E at 2050 on 8 April. The Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS) reported that an ash plume rose 500 m and drifted E on 9 April. IVS reported an Aviation Color Code of Yellow (the second lowest level on a four-color scale) on 9 April and Green (the lowest level on a four-color scale) the rest of the week. 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. Sources: 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYmI8cpJmA$> ; Tokyo Volcanic Ash Advisory Center (VAAC) http://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html <https://urldefense.com/v3/__http://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYn2zi-PHQ$> *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 ongoing inflation and frequent explosions at Poás during 9-15 April. Sulfur dioxide emissions recorded by a mobile Differential Optical Absorption Spectroscopy (DOAS) instrument measured an average of 223 ± 210 tonnes per day (t/d) and a maximum flux of 5,524 ± 854 t/d on 9 April. Seismographs and infrasound sensors recorded volcanic tremor and acoustic signals. Gas-and-ash emissions typically rose 100-400 m above the crater. At 2144 on 8 April a large phreatomagmatic event lasting 15-20 minutes produced an ash plume that rose 1.5 km above the crater and drifted SW. Blocks were ejected onto the crater floor. Frequent ash emissions rising less than 100 m above the crater continued following this event. The Washington VAAC reported that an ash plume rose 1.5 km above the crater and drifted S at 2350 on 8 April, based on webcam imagery. At 0738 on 9 April there was a transition to continuous ash emissions that rose 300 m above the crater and drifted W. Light ashfall and a sulfur odor was reported, along with damage to nearby vegetation and crops, on the middle and upper parts of the W flank near San Luis (11 km SW) and Trojas de Grecia. According to the Washington VAAC, at 0820 on 9 April an ash plume rose to 3 km (9,800 ft) a.s.l. and drifted W, based on webcam images. During 1116 and 1126 on 11 April several short, intense, eruptive events were recorded. Residents of Poás, Grecia (16 km SW), and Zarcero reported a sulfurous odor and symptoms that included headaches, nausea, sore throat, teary eyes, nasal drip, and allergies relating to the gas emissions and volcanic particles. During 12-13 April ash emissions and higher energy tremors and acoustic infrasound signals were recorded; the height of the ash emissions could not be determined due to cloudy weather conditions. On 12 April at 0710 the Washington VAAC reported a possible ash plume that rose to 3 km (9,800 ft) a.s.l. and drifted SW, though cloudy weather obscured clear views of the summit. 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. Sources: 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYmhDgzhOw$> ; Washington Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/messages.html <https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlFRkma-A$> *Ongoing Activity* *Ahyi* | United States | 20.42°N, 145.03°E | Summit elev. -75 m Unrest at Ahyi Seamount may have continued during 4-11 April. A diffuse plume of discolored water in the vicinity of the seamount was last identified in a satellite image on 30 March, indicating possible submarine activity. No signals coming from the direction of Ahyi were identified in data from underwater pressure sensors near Wake Island (about 2,270 km E of Ahyi), though sporadic data outages occurred during the week. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYnDzaTP4A$> *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 7-14 April. Nightly crater incandescence was visible in webcam images. An explosion at 1148 on 7 April generated an ash plume that rose 2.9 km above the crater rim and drifted SE. Large blocks were ejected 600-900 m from the vent. An eruptive event at 1227 on 7 April generated an ash plume that rose 1.3 km above the crater rim and drifted SE. An explosion at 2220 on 13 April generated an ash plume that rose 1.2 km above the crater rim and drifted E. Large blocks were ejected 500-700 m from the vent. On 7 April sulfur dioxide emissions were slightly higher than average at 1,800 tons per day. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYnJM5TwAg$> *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 3-10 April. 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 crater incandescence was visible during dark hours. Ash plumes generated from these debris avalanches rose 200-1,100 m above the summit and drifted in different directions during 4-5 and 8-10 April. Lava-dome extrusion significantly increased on 11 April, causing collapses and hot avalanches of material from the E part of the dome; subsequent ash plumes rose as high as 1.1 km above the summit and drifted at least 90 km NE. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYmBB94c9Q$> ; Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS) http://www.kscnet.ru/ivs/ <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYmI8cpJmA$> *Dukono* | Indonesia | 1.6992°N, 127.8783°E | Summit elev. 1273 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Dukono continued during 9-15 April. White-and-gray ash plumes rose 200-1,000 m above the crater rim and drifted in multiple directions. Ash plumes were reported during 10-15 April that rose 600-1,300 m above the crater and drifted in different directions. On 11 April at 1038 a white-to-gray ash plume rose 1.3 km above the summit and drifted SE to S. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlTVL1KUg$> *Great Sitkin* | United States | 52.076°N, 176.13°W | Summit elev. 1740 m The Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick flow in Great Sitkinâ??s summit crater during 9-15 April. Small daily earthquakes were detected by the seismic network. Steaming from the vent region and slightly elevated surface temperatures were detected in satellite and webcam images during 9-10 March. Weather clouds often obscured views of the volcano. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale). Geologic Summary. The Great Sitkin volcano forms much of the northern side of Great Sitkin Island. A younger volcano capped by a small, 0.8 x 1.2 km ice-filled summit caldera was constructed within a large late-Pleistocene or early Holocene scarp formed by massive edifice failure that truncated an older edifice and produced a submarine debris avalanche. Deposits from this and an even older debris avalanche from a source to the south cover a broad area of the ocean floor north of the volcano. The summit lies along the eastern rim of the younger collapse scarp. Deposits from an earlier caldera-forming eruption of unknown age cover the flanks of the island to a depth up to 6 m. The small younger caldera was partially filled by lava domes emplaced in 1945 and 1974, and five small older flank lava domes, two of which lie on the coastline, were constructed along northwest- and NNW-trending lines. Hot springs, mud pots, and fumaroles occur near the head of Big Fox Creek, south of the volcano. Eruptions have been recorded since the late-19th century. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://avo.alaska.edu/ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYk8O9l3vw$> *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 9-15 April. Daily dense gray ash plumes rose 300-700 m above the summit and drifted in multiple directions. Nighttime crater incandescence was visible in a webcam image on 15 April. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlTVL1KUg$> *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 9-15 April, following a notable explosion on 8 April. The seismic network recorded 7-33 daily volcanic earthquakes, including one period of volcanic tremor lasting 18 minutes during 8-9 April, and five periods of tremor lasting 8-23 minutes during 14-15 April. Daily sulfur dioxide emissions ranged from 1,633 to 2,202 tonnes per day. Gas-and-steam emissions that occasionally contained ash rose 50-800 m above the crater rim and drifted NW, SW, W, and WNW. Ash emissions were recorded at 1152, 1453, and 1717 on 14 April that lasted as long as four hours and 13 minutes. A voluminous gray ash plume rose 800 m, 600 m, and 300-350 m above the crater rim and drifted WNW, WNW, and W, respectively. Light ashfall and a sulfur odor was reported in Bago City. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYloqQQAlQ$> *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 9-15 April. Seismic tremor rapidly dropped in intensity on 9 April at 0945 but continued at low levels. Around the same time, lava fountaining at the S vent had stopped, but gas-and-steam emissions and weak-to-moderate nighttime incandescence persisted. Sulfur dioxide emission rates were 1,200 tonnes per day. During 13-14 April both the N and S vents had strong incandescence and continued to emit gas-and-steam. Occasional spattering was visible at the N vent based on webcam images. Tremor increased late on 13 April. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYmlJDgBjg$> *Lewotobi* | Indonesia | 8.542°S, 122.775°E | Summit elev. 1703 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Lewotobi Laki-laki continued during 9-15 April. Dense gray ash plumes that rose 300-1,700 m above the summit during 9-11 and 14-15 April drifted NW, W, N, and NE. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 6 km away from the center of Laki-laki. Geologic Summary. The Lewotobi edifice in eastern Flores Island is composed of the two adjacent Lewotobi Laki-laki and Lewotobi Perempuan stratovolcanoes (the "husband and wife"). Their summits are less than 2 km apart along a NW-SE line. The conical Laki-laki to the NW has been frequently active during the 19th and 20th centuries, while the taller and broader Perempuan has had observed eruptions in 1921 and 1935. Small lava domes have grown during the 20th century in both of the summit craters, which are open to the north. A prominent cone, Iliwokar, occurs on the E flank of Perampuan. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlTVL1KUg$> *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 9-15 April. White steam-and-gas plumes rose 20-400 m above the summit of the cone and drifted W and NW on most days; white-and-gray plumes rose 50-100 m and drifted E and SE on 14 April. Ash plumes rose 300-900 m above the summit and drifted W, NW, and SE on 10-12 and 15 April. Some nighttime crater incandescence was visible on 15 April. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlTVL1KUg$> *Marapi* | Indonesia | 0.38°S, 100.474°E | Summit elev. 2885 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Marapiâ??s Verbeek Crater (on Sumatra) continued during 9-15 April. At 0750 on 9 April the Darwin VAAC reported an ash plume that rose to 4.3 km (14,000 ft) a.s.l. and drifted W, according to a ground observer. White gas-and-steam emissions rose 100-200 m above the summit and drifted in multiple directions on 9, 10, 13, and 14 April. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the active crater. Geologic Summary. Gunung Marapi, not to be confused with the better-known Merapi volcano on Java, is Sumatra's most active volcano. This massive complex stratovolcano rises 2,000 m above the Bukittinggi Plain in the Padang Highlands. A broad summit contains multiple partially overlapping summit craters constructed within the small 1.4-km-wide Bancah caldera. The summit craters are located along an ENE-WSW line, with volcanism migrating to the west. More than 50 eruptions, typically consisting of small-to-moderate explosive activity, have been recorded since the end of the 18th century; no lava flows outside the summit craters have been reported in historical time. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlTVL1KUg$> ; 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlQgTzXuA$> *Merapi* | Indonesia | 7.54°S, 110.446°E | Summit elev. 2910 m The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 4-10 April. Seismicity remained at high levels. The SW lava dome produced 31 lava avalanches that traveled as far as 2 km SW down the Bebeng drainage, 18 that traveled as far as 1.8 km SW down the Krasak drainage, 37 that traveled as far as 1.9 km W down the Sat/Putih drainage, and one that descended the Boyong drainage on the S flank as far as 1.5 km. Small morphological changes to the SW lava dome resulted from minor collapses of material. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location. Geologic Summary. Merapi, one of Indonesia's most active volcanoes, lies in one of the world's most densely populated areas and dominates the landscape immediately north of the major city of Yogyakarta. It is the youngest and southernmost of a volcanic chain extending NNW to Ungaran volcano. Growth of Old Merapi during the Pleistocene ended with major edifice collapse perhaps about 2,000 years ago, leaving a large arcuate scarp cutting the eroded older Batulawang volcano. Subsequent growth of the steep-sided Young Merapi edifice, its upper part unvegetated due to frequent activity, began SW of the earlier collapse scarp. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated lands on the western-to-southern flanks and caused many fatalities. Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) http://www.merapi.bgl.esdm.go.id/ <https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYl15LZ_BQ$> *Popocatepetl* | Mexico | 19.023°N, 98.622°W | Summit elev. 5393 m The Centro Nacional de Prevención de Desastres (CENAPRED) reported that eruptive activity continued at Popocatépetl during 9-15 April. The seismic network recorded 18-94 long-period events per day on most days, accompanied by steam-and-gas emissions. In addition, the seismic network also recorded daily low-amplitude tremor, characterized by harmonic and high-frequency signals, with periods lasting from 11 minutes to five hours and 11 minutes. A single volcano-tectonic earthquake was detected on 9 April. According to the Washington VAAC an ash plume was visible in webcam and satellite images on 10 April rising 6 km (20,000 ft) a.s.l. and drifting E. The Alert Level remained at Yellow, Phase Two (the middle level on a three-color scale) and the public was warned to stay 12 km away from the crater. Geologic Summary. Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, rises 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 400 x 600 m wide crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano. At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas to the south. The modern volcano was constructed south of the late-Pleistocene to Holocene El Fraile cone. Three major Plinian eruptions, the most recent of which took place about 800 CE, have occurred since the mid-Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since Pre-Columbian time. Sources: Centro Nacional de Prevencion de Desastres (CENAPRED) https://www.gob.mx/cenapred <https://urldefense.com/v3/__https://www.gob.mx/cenapred__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYntHXPZnw$> ; Washington Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/messages.html <https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlFRkma-A$> *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 9-15 April. Seismicity included 60-106 daily explosions, long-period earthquakes, harmonic tremor, and tremor associated with emissions. Multiple daily ash-and-gas plumes rose 200-2,200 m above the crater rim and drifted mainly NW, SW, and W. Webcams recorded multiple nightly instances of incandescent material descending the flanks as far as 1.1 km below the crater rim. During 8-9 April several pyroclastic flows were recorded, reaching more than 700 m below the crater on the SSW flanks. On the morning of 10 April a small lahar was recorded descending the S flank. That same day, a pyroclastic flow traveled down the SSW flank. Webcam images on 11 April showed another pyroclastic flow descending the SSW flank, with another on 12 April reaching 500 m below the crater on the SW flank. Several pyroclastic flows on the SW flank reached 1 km below the crater on 13 April. On 14 April two pyroclastic flows descended the SE flank as far as 800 m below the crater. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlg4OGYpg$> ; SecretarÃa de Gestión de Riesgos (SGR) http://www.gestionderiesgos.gob.ec/ <https://urldefense.com/v3/__http://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYkTWWWnLw$> *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 9-15 April. The seismic network recorded 45-125 daily explosions. Weather clouds often obscured views, but daily gas-and-ash plumes were visible rising 300-2,100 m above the summit and drifting in different directions. Nighttime crater incandescence was often visible. During the night of 8 April several incandescent avalanches were detected 400 m below the crater rim. During the early morning of 11 April several incandescent eruptions were visible above the crater level. A webcam image showed incandescent ejecta on the SE drainage. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlg4OGYpg$> ; SecretarÃa de Gestión de Riesgos (SGR) http://www.gestionderiesgos.gob.ec/ <https://urldefense.com/v3/__http://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYkTWWWnLw$> *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 eruptive activity at Santa Mariaâ??s Santiaguito dome complex during 9-15 April 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, E, SE, and NE. Effusion of blocky lava and collapses of material produced block avalanches that mainly descended the S, SW, and W flanks. Collapsed material sometimes produced short pyroclastic flows that descended the flanks in all directions. Incandescence was visible at Caliente dome and upper part of the SW flank lava flow. On 9 April heavy rainfall generated lahars in the Tambor drainage (SSW) that carried blocks up to 1 m in diameter mixed with fine sediment, tree trunks, and branches. A sulfurous odor was also reported. Ashfall was reported from Nuevo Palmar (12 km SSW) and Pueblo Nuevo to San Felipe (15 km SSW) and Loma Linda (7 km W) during 11-12 April and in Las MarÃas (9.5 km S), Calaguaché (9 km S), and Belén (10 km S) during 12-13 April. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlGk7uVVg$> *Semeru* | Indonesia | 8.108°S, 112.922°E | Summit elev. 3657 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity continued at Semeru during 9-15 April. Daily ash plumes rose 400-1,000 m above the summit and drifted SW, S, and NE; ash plumes were not visible on 13 April. White gas-and-steam emissions rose 100 m above the summit and drifted N, NE, and S on 10 April. The Alert Level remained at 2 (the second lowest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards. Geologic Summary. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYlTVL1KUg$> *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 3-10 April. 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!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYmBB94c9Q$> *Stromboli* | Italy | 38.789°N, 15.213°E | Summit elev. 924 m The Sezione di Catania - Osservatorio Etneo (INGV) reported that eruptive activity continued at Stromboli during 7-13 April. Webcam images showed Strombolian activity at four vents in Area N within the upper part of the Sciara del Fuoco and from at least two vents in Area C-S (South-Central Crater) on the crater terrace. The vents in Area N continued to produce low-to-medium-intensity explosions at a rate of 5-15 events per hour, ejecting lapilli and bombs less than 150 m above the vents. Explosions at the vents in Area C-S ejected tephra above the vent at a rate of 1-7 events per hour. The Alert Level remained at Orange (the second highest level on a four-level scale). Geologic Summary. Spectacular incandescent nighttime explosions at Stromboli have long attracted visitors to the "Lighthouse of the Mediterranean" in the NE Aeolian Islands. This volcano has lent its name to the frequent mild explosive activity that has characterized its eruptions throughout much of historical time. The small island is the emergent summit of a volcano that grew in two main eruptive cycles, the last of which formed the western portion of the island. The Neostromboli eruptive period took place between about 13,000 and 5,000 years ago. The active summit vents are located at the head of the Sciara del Fuoco, a prominent scarp that formed about 5,000 years ago due to a series of slope failures which extends to below sea level. The modern volcano has been constructed within this scarp, which funnels pyroclastic ejecta and lava flows to the NW. Essentially continuous mild Strombolian explosions, sometimes accompanied by lava flows, have been recorded for more than a millennium. Source: Sezione di Catania - Osservatorio Etneo (INGV) http://www.ct.ingv.it/ <https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYn9IuXbmg$> *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 7-14 April. Incandescence was observed nightly in webcam images. Eruptive activity generated emissions that rose 1 km above the crater rim. Ashfall was reported by the Suwanosejima Branch of the Toshima Village Office (3.5 km SSW). The Alert Level remained at 2 (the second level on a five-level scale) and the public was warned to stay at least 1.5 km away from the crater. Geologic Summary. The 8-km-long island of Suwanosejima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two active summit craters. The summit is truncated by a large breached crater extending to the sea on the E flank that was formed by edifice collapse. One of Japan's most frequently active volcanoes, it was in a state of intermittent Strombolian activity from Otake, the NE summit crater, between 1949 and 1996, after which periods of inactivity lengthened. The largest recorded eruption took place in 1813-14, when thick scoria deposits covered residential areas, and the SW crater produced two lava flows that reached the western coast. At the end of the eruption the summit of Otake collapsed, forming a large debris avalanche and creating an open collapse scarp extending to the eastern coast. The island remained uninhabited for about 70 years after the 1813-1814 eruption. Lava flows reached the eastern coast of the island in 1884. Only about 50 people live on the island. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!dgPwUH7T_TQNe_xt4fltyfGTW8A4UVDZlotT5vcRJEHCeiAVWCWmZOgx8-iAAM3oLpYuPWJfU0tqPcM6pYnJM5TwAg$> 4-4-4-4-4-4-4-4-4-4-4-4-4 ============================================================== 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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