1-1-1-1-1-1-1-1-1-1-1-1-1-1 From: "Bennis, Kadie" <BennisK@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 30 March-5 April 2022 Kadie Bennis - Weekly Report Editor (bennisk@xxxxxx) URL: https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lqVMrypA$ <https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKjm7psN8$> New Activity/Unrest: Agung, Bali | Poas, Costa Rica | Purace, Colombia Ongoing Activity: Aira, Kyushu (Japan) | Ambae, Vanuatu | Ambrym, Vanuatu | Bezymianny, Central Kamchatka (Russia) | Dukono, Halmahera | Fuego, South-Central Guatemala | Great Sitkin, Andreanof Islands (USA) | Ibu, Halmahera | Karymsky, Eastern Kamchatka (Russia) | Kavachi, Solomon Islands | Kikai, Ryukyu Islands (Japan) | Kilauea, Hawaiian Islands (USA) | Kirishimayama, Kyushu (Japan) | Krakatau, Sunda Strait | Lewotolok, Lembata Island | Merapi, Central Java | Nevados de Chillan, Central Chile | Pavlof, Alaska Peninsula, Alaska | Popocatepetl, Mexico | Reventador, Ecuador | Rincon de la Vieja, Costa Rica | Ruapehu, North Island (New Zealand) | Sangay, Ecuador | Santa Maria, Southwestern Guatemala | Sao Jorge, Azores | Semeru, Eastern Java | Semisopochnoi, Aleutian Islands (USA) | Sheveluch, Central Kamchatka (Russia) | Sirung, Pantar Island | Suwanosejima, Ryukyu Islands (Japan) | Taal, Luzon (Philippines) | Telica, Sierra de los Marrabios | Whakaari/White Island, North Island (New Zealand) | Wolf, Isla Isabela (Galapagos) | Yasur, Vanuatu 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 Agung | Bali | 8.343°S, 115.508°E | Summit elev. 2997 m Based on ground reports, satellite imagery, and wind model data, the Darwin VAAC reported that during 3 April an ash plume from Agung rose to 3.7 km (12,000 ft) a.s.l. The Alert Level remained at 1 (on a scale of 1-4). Geologic Summary. Symmetrical Agung stratovolcano, Bali's highest and most sacred mountain, towers over the eastern end of the island. The volcano, whose name means "Paramount," rises above the SE rim of the Batur caldera, and the northern and southern flanks extend to the coast. The summit area extends 1.5 km E-W, with the high point on the W and a steep-walled 800-m-wide crater on the E. The Pawon cone is located low on the SE flank. Only a few eruptions dating back to the early 19th century have been recorded in historical time. The 1963-64 eruption, one of the largest in the 20th century, produced voluminous ashfall along with devastating pyroclastic flows and lahars that caused extensive damage and many fatalities. Source: Darwin Volcanic Ash Advisory Centre (VAAC) https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lkKq2EjU$ <https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKgih5cGc$> Poas | Costa Rica | 10.2°N, 84.233°W | Summit elev. 2697 m OVSICORI-UNA reported that on 6 April at 0242 a phreatic explosion was detected at the N wall crater wall at Poás, generating a plume that rose 500 m above the crater. Activity lasted for three minutes. Geologic Summary. The broad vegetated edifice of Poás, one of the most active volcanoes of Costa Rica, contains three craters along a N-S line. The frequently visited multi-hued summit crater lakes of the basaltic-to-dacitic volcano are easily accessible by vehicle from the nearby capital city of San José. A N-S-trending fissure cutting the complex stratovolcano extends to the lower N flank, where it has produced the Congo stratovolcano and several lake-filled maars. The southernmost of the two summit crater lakes, Botos, last erupted about 7,500 years ago. The more prominent geothermally heated northern lake, Laguna Caliente, is one of the world's most acidic natural lakes, with a pH of near zero. It has been the site of frequent phreatic and phreatomagmatic eruptions since an eruption was reported in 1828. Eruptions often include geyser-like ejections of crater-lake water. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lXBIINh4$ <https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKypaqglU$> Purace | Colombia | 2.32°N, 76.4°W | Summit elev. 4650 m The Popayán Observatory, part of the Servicio Geologico Colombiano (SGC) reported that there was an increase in the number of volcano-tectonic earthquakes associated with rock fractures at Puracé. On 28 March, 479 volcanic tremors, 183 long-period (LP), and 119 volcanic tremor (TR) events were detected. Seismicity was detected 800 m SE from the crater at average depths of 2 km. An earthquake that occurred at 1214 on 29 March had a magnitude of 3.3. That same day, two cracks approximately 40 m long produced gas-and-steam emissions. On 30 March the Volcano Alert Level rose to 3 or Yellow (the second lowest on a four-color scale). Geologic Summary. One of the most active volcanoes of Colombia, Puracé consists of an andesitic stratovolcano with a 500-m-wide summit crater that was constructed over a dacitic shield volcano. It lies at the NW end of a volcanic massif opposite Pan de Azúcar stratovolcano, 6 km SE. A NW-SE-trending group of seven cones and craters, Los Coconucos, lies between the two larger edifices. Frequent explosive eruptions in the 19th and 20th centuries have modified the morphology of the summit crater. The largest eruptions occurred in 1849, 1869, and 1885. Source: Servicio Geológico Colombiano (SGC) https://urldefense.com/v3/__https://www2.sgc.gov.co/volcanes/index.html__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lu-OEa2A$ <https://urldefense.com/v3/__https://www2.sgc.gov.co/volcanes/index.html__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKJFm-IZE$> Ongoing Activity Aira | Kyushu (Japan) | 31.593°N, 130.657°E | Summit elev. 1117 m JMA reported that very small eruptive events were recorded at Minamidake Crater (at Aira Calderaâ??s Sakurajima volcano) during 29 March through 4 April. After 2 April, incandescence was observed at night with a high-sensitivity surveillance camera. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater. Geologic Summary. The Aira caldera in the northern half of Kagoshima Bay contains the post-caldera Sakurajima volcano, one of Japan's most active. Eruption of the voluminous Ito pyroclastic flow accompanied formation of the 17 x 23 km caldera about 22,000 years ago. The smaller Wakamiko caldera was formed during the early Holocene in the NE corner of the Aira caldera, along with several post-caldera cones. The construction of Sakurajima began about 13,000 years ago on the southern rim of Aira caldera and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kitadake summit cone ended about 4850 years ago, after which eruptions took place at Minamidake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu's largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76. Source: Japan Meteorological Agency (JMA) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lXiyqkJE$ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpK5RVaW8o$> Ambae | Vanuatu | 15.389°S, 167.835°E | Summit elev. 1496 m On 31 March the Vanuatu Meteorology and Geo-Hazards (VMGD) reported that explosions at the cone in Ambaeâ??s Lake Voui continued to produce steam and ash emissions. Wet tephra that was also ejected from the cone during this activity remained within the caldera. Light ashfall was reported in nearby villages. The Alert Level remained at 2 (on a scale of 0-5) and the public was warned to stay outside of the Danger Zone, defined as a 2-km radius around the active vents in Lake Voui, and away from drainages during heavy rains. Geologic Summary. The island of Ambae, also known as Aoba, is a massive 2,500 km3 basaltic shield that is the most voluminous volcano of the New Hebrides archipelago. A pronounced NE-SW-trending rift zone dotted with scoria cones gives the 16 x 38 km island an elongated form. A broad pyroclastic cone containing three crater lakes (Manaro Ngoru, Voui, and Manaro Lakua) is located at the summit within the youngest of at least two nested calderas, the largest of which is 6 km in diameter. That large central edifice is also called Manaro Voui or Lombenben volcano. Post-caldera explosive eruptions formed the summit craters about 360 years ago. A tuff cone was constructed within Lake Voui (or Vui) about 60 years later. The latest known flank eruption, about 300 years ago, destroyed the population of the Nduindui area near the western coast. Source: Vanuatu Meteorology and Geo-Hazards Department (VMGD) https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lROHxFB8$ <https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKzA7_tSQ$> Ambrym | Vanuatu | 16.25°S, 168.12°E | Summit elev. 1334 m On 31 March the Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that nighttime crater incandescence from Ambrymâ??s Benbow Crater was no longer visible, though steam emissions persisted. The Alert Level remained at 2 (on a scale of 0-5). VMGD warned the public to stay outside of Permanent Danger Zone A, defined as a 1-km radius around Benbow Crater and a 2-km radius around Marum Crater, and additionally to stay 500 m away from the ground cracks created by the December 2018 eruption. Geologic Summary. Ambrym, a large basaltic volcano with a 12-km-wide caldera, is one of the most active volcanoes of the New Hebrides Arc. A thick, almost exclusively pyroclastic sequence, initially dacitic then basaltic, overlies lava flows of a pre-caldera shield volcano. The caldera was formed during a major Plinian eruption with dacitic pyroclastic flows about 1,900 years ago. Post-caldera eruptions, primarily from Marum and Benbow cones, have partially filled the caldera floor and produced lava flows that ponded on the floor or overflowed through gaps in the caldera rim. Post-caldera eruptions have also formed a series of scoria cones and maars along a fissure system oriented ENE-WSW. Eruptions have apparently occurred almost yearly during historical time from cones within the caldera or from flank vents. However, from 1850 to 1950, reporting was mostly limited to extra-caldera eruptions that would have affected local populations. Source: Vanuatu Meteorology and Geo-Hazards Department (VMGD) https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lROHxFB8$ <https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKzA7_tSQ$> Bezymianny | Central Kamchatka (Russia) | 55.972°N, 160.595°E | Summit elev. 2882 m KVERT reported that a daily thermal anomaly over Bezymianny was visible in satellite images during 26 March through 1 April. Strong fumarolic activity, incandescence at the lava dome, and avalanches were also reported. Dome collapses were detected on 25 and 31 March and ash clouds rose to 4 km (13,000 ft) a.s.l., expanding 40 km E and 20 km SW, respectively. The Aviation Color Code remained at Yellow (the second lowest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. Prior to its noted 1955-56 eruption, Bezymianny had been considered extinct. The modern volcano, much smaller in size than its massive neighbors Kamen and Kliuchevskoi, was formed about 4700 years ago over a late-Pleistocene lava-dome complex and an ancestral edifice built about 11,000-7000 years ago. Three periods of intensified activity have occurred during the past 3000 years. The latest period, which was preceded by a 1000-year quiescence, began with the dramatic 1955-56 eruption. This eruption, similar to that of St. Helens in 1980, produced a large horseshoe-shaped crater that was formed by collapse of the summit and an associated lateral blast. Subsequent episodic but ongoing lava-dome growth, accompanied by intermittent explosive activity and pyroclastic flows, has largely filled the 1956 crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lDQv1HB8$ <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKu2pK734$> Dukono | Halmahera | 1.693°N, 127.894°E | Summit elev. 1229 m Based on satellite and wind model data, the Darwin VAAC reported that during 29 March through 4 April ash plumes from Dukono rose to 2.1 km (7,000 ft) a.s.l. and drifted SE, S, E, and ENE. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km exclusion zone. Geologic Summary. Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, occurred from 1933 until at least the mid-1990s, when routine observations were curtailed. During a major eruption in 1550, a lava flow filled in the strait between Halmahera and the north-flank cone of Gunung Mamuya. This complex volcano presents a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also been active during historical time. Source: Darwin Volcanic Ash Advisory Centre (VAAC) https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lkKq2EjU$ <https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKgih5cGc$> Fuego | South-Central Guatemala | 14.473°N, 90.88°W | Summit elev. 3763 m INSIVUMEH reported that 4-8 explosions per hour were detected at Fuego during 30 March through 5 April, generating gas-and-ash emissions that rose to 4.9 km (16,000 ft) a.s.l. and drifted as far as 30 km NW, W, SW, and S. Block avalanches descended the Las Lajas (SE), Seca (W), Ceniza (SSW), Taniluyá (SW), Trinidad (S), Honda, and Santa Teresa drainages. At night, incandescence was observed up to 150 m above the crater. Fine ashfall was reported in Panimaché I and II (8 km SW), Morelia (9 km SW), Santa SofÃa (12 km SW), Finca Palo Verde, Yepocapa (8 km NW), El Porvenir (8 km ENE), and Sangre de Cristo (8 km WSW). Shock waves from the explosions and rumbling sounds rattled local structures. Based on satellite and wind model data, the Washington VAAC reported that during 29 March through 4 April ash plumes from Fuego rose to 4.9 km (16,000 ft) a.s.l. and drifted SE, E, SW, S, WNW, WSW. Geologic Summary. Volcán Fuego, one of Central America's most active volcanoes, is also one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between Fuego and Acatenango to the north. Construction of Meseta dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at the mostly andesitic Acatenango. Eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. Frequent vigorous historical eruptions have been recorded since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lFDB_Xng$ <https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKaW3eIiQ$>; Coordinadora Nacional para la Reducción de Desastres (CONRED) https://urldefense.com/v3/__http://conred.gob.gt/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0l8oltkgQ$ <https://urldefense.com/v3/__http://conred.gob.gt/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpK-uES3ag$>; Washington Volcanic Ash Advisory Center (VAAC) https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lmFFcU28$ <https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKRoQ9EPI$> Great Sitkin | Andreanof Islands (USA) | 52.076°N, 176.13°W | Summit elev. 1740 m AVO reported that slow lava effusion at Great Sitkin continued during 30 March through 5 April and low seismicity persisted. Cloud cover prevented views of the volcano most of the week, but slow lava effusion continued; minor flow fronts advanced from the W and S lobes, as well as the E margin. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively. Geologic Summary. The Great Sitkin volcano forms much of the northern side of Great Sitkin Island. A younger parasitic volcano capped by a small, 0.8 x 1.2 km ice-filled summit caldera was constructed within a large late-Pleistocene or early Holocene scarp formed by massive edifice failure that truncated an ancestral volcano and produced a submarine debris avalanche. Deposits from this and an older debris avalanche from a source to the south cover a broad area of the ocean floor north of the volcano. The summit lies along the eastern rim of the younger collapse scarp. Deposits from an earlier caldera-forming eruption of unknown age cover the flanks of the island to a depth up to 6 m. The small younger caldera was partially filled by lava domes emplaced in 1945 and 1974, and five small older flank lava domes, two of which lie on the coastline, were constructed along northwest- and NNW-trending lines. Hot springs, mud pots, and fumaroles occur near the head of Big Fox Creek, south of the volcano. Historical eruptions have been recorded since the late-19th century. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lZ_oApVc$ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKnd7MHag$> Ibu | Halmahera | 1.488°N, 127.63°E | Summit elev. 1325 m PVMBG reported that the eruption at Ibu continued during 25-31 March. On 30 March at 1048 an ash plume rose 1 km above the summit that drifted S. Roughly 58 avalanches traveled 100-400 m N and NW. The Alert Level remained at a 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater and 3.5 km away on the N side. Geologic Summary. The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, has contained several small crater lakes. The 1.2-km-wide outer crater is breached on the N, creating a steep-walled valley. A large cone grew ENE of the summit, and a smaller one to the WSW has fed a lava flow down the W flank. A group of maars is located below the N and W flanks. The first observed and recorded eruption was a small explosion from the summit crater in 1911. Eruptive activity began again in December 1998, producing a lava dome that eventually covered much of the floor of the inner summit crater along with ongoing explosive ash emissions. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0l__8Vm1A$ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKoFi5FQw$> Karymsky | Eastern Kamchatka (Russia) | 54.049°N, 159.443°E | Summit elev. 1513 m KVERT reported that a thermal anomaly over Karymsky was visible in satellite images during 24-26 March. The volcano was either quiet or obscured by clouds on the other days during 27 March through 1 April. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lDQv1HB8$ <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKu2pK734$> Kavachi | Solomon Islands | 8.991°S, 157.979°E | Summit elev. -20 m Satellite data showed discolored water around Kavachi on 31 March. The discolored water fanned out to the S over a short distance, though it was not clearly observed due to cloudy weather. Geologic Summary. Named for a sea-god of the Gatokae and Vangunu peoples, Kavachi is one of the most active submarine volcanoes in the SW Pacific, located in the Solomon Islands south of Vangunu Island. Sometimes referred to as Rejo te Kvachi ("Kavachi's Oven"), this shallow submarine basaltic-to-andesitic volcano has produced ephemeral islands up to 1 km long many times since its first recorded eruption during 1939. Residents of the nearby islands of Vanguna and Nggatokae (Gatokae) reported "fire on the water" prior to 1939, a possible reference to earlier eruptions. The roughly conical edifice rises from water depths of 1.1-1.2 km on the north and greater depths to the SE. Frequent shallow submarine and occasional subaerial eruptions produce phreatomagmatic explosions that eject steam, ash, and incandescent bombs. On a number of occasions lava flows were observed on the ephemeral islands. Sources: Sentinel Hub https://urldefense.com/v3/__https://sentinel-hub.com/explore/sentinel-playground__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0l1tA92Bc$ <https://urldefense.com/v3/__https://sentinel-hub.com/explore/sentinel-playground__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKX2TaLPM$>; Culture Volcan https://urldefense.com/v3/__https://laculturevolcan.blogspot.com/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lkd4QngI$ <https://urldefense.com/v3/__https://laculturevolcan.blogspot.com/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKd9dOiDo$> Kikai | Ryukyu Islands (Japan) | 30.793°N, 130.305°E | Summit elev. 704 m JMA reported that eruptive activity continued to be recorded at Satsuma Iwo-jima, a subaerial part of Kikaiâ??s NW caldera rim, during 29 March through 4 April. White gas-and-steam plumes rose 1 km above the crater rim. Surveillance cameras observed nightly incandescence. The Alert Level remained at 2 (on a 5-level scale), and residents were warned to stay 500 m away from the crater. Geologic Summary. Kikai is a mostly submerged, 19-km-wide caldera near the northern end of the Ryukyu Islands south of Kyushu. It was the source of one of the world's largest Holocene eruptions about 6,300 years ago when rhyolitic pyroclastic flows traveled across the sea for a total distance of 100 km to southern Kyushu, and ashfall reached the northern Japanese island of Hokkaido. The eruption devastated southern and central Kyushu, which remained uninhabited for several centuries. Post-caldera eruptions formed Iodake lava dome and Inamuradake scoria cone, as well as submarine lava domes. Historical eruptions have occurred at or near Satsuma-Iojima (also known as Tokara-Iojima), a small 3 x 6 km island forming part of the NW caldera rim. Showa-Iojima lava dome (also known as Iojima-Shinto), a small island 2 km E of Tokara-Iojima, was formed during submarine eruptions in 1934 and 1935. Mild-to-moderate explosive eruptions have occurred during the past few decades from Iodake, a rhyolitic lava dome at the eastern end of Tokara-Iojima. Source: Japan Meteorological Agency (JMA) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lXiyqkJE$ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpK5RVaW8o$> Kilauea | Hawaiian Islands (USA) | 19.421°N, 155.287°W | Summit elev. 1222 m HVO reported that lava effusion from vents in the lower W wall of Kilaueaâ??s Halema`uma`u Crater continued at variable rates during 30 March through 5 April. Lava from a vent flowed into the active W part of the lava lake and onto the crater floor. Numerous and sustained ooze outs of lava along the lakeâ??s margins; effusion along interior surface fractures persisted during the week but showed decreasing activity. On 31 March a hornito that was forming on the E side of the lake exhibited spattering throughout the day. HVO noted that by 29 March about 64 million cubic meters of lava had been erupted since the current eruption began, raising the crater floor by 96 m (315 ft). The sulfur dioxide emission rate was approximately 3,100 tons/day, based on measurements made on 31 March. During 2-5 April continued ooze outs were occurring along the E half of the crater floor and NW margin, but at a decreased rate, and crustal overturning occurred occasionally on the NW margin. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively. 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://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lTr68fMI$ <https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKq2HwmY8$> Kirishimayama | Kyushu (Japan) | 31.934°N, 130.862°E | Summit elev. 1700 m JMA reported a high number of volcanic earthquakes just below Shinmoedake (Shinmoe peak, a stratovolcano of the Kirishimayama volcano group). On 31 March the number of volcanic earthquakes increased below Ebino Kogen (located on the NW flank of the Karakunidake stratovolcano, about 5 km NW of Shinmoedake). Fumarolic plumes continued to rise from a fissure on the W flank. The Alert Level remained at 2 (on a 5-level scale), and residents were warned to stay 2 km away from the crater. The public was warned to stay at least 2 km away from the crater. Geologic Summary. Kirishimayama is a large group of more than 20 Quaternary volcanoes located north of Kagoshima Bay. The late-Pleistocene to Holocene dominantly andesitic group consists of stratovolcanoes, pyroclastic cones, maars, and underlying shield volcanoes located over an area of 20 x 30 km. The larger stratovolcanoes are scattered throughout the field, with the centrally located Karakunidake being the highest. Onamiike and Miike, the two largest maars, are located SW of Karakunidake and at its far eastern end, respectively. Holocene eruptions have been concentrated along an E-W line of vents from Miike to Ohachi, and at Shinmoedake to the NE. Frequent small-to-moderate explosive eruptions have been recorded since the 8th century. Source: Japan Meteorological Agency (JMA) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lXiyqkJE$ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpK5RVaW8o$> Krakatau | Sunda Strait | 6.102°S, 105.423°E | Summit elev. 155 m PVMBG reported that the eruption at Anak Krakatau continued during 25-31 March. On 1326 on 30 March an eruption that lasted 96 seconds generated a gray-black ash plume that rose 700 m above the summit and drifted NE based on webcam images. White gas-and-steam emissions rose 25-100 m above the summit. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the crater. Geologic Summary. The renowned volcano Krakatau (frequently misstated as Krakatoa) lies in the Sunda Strait between Java and Sumatra. Collapse of the ancestral Krakatau edifice, perhaps in 416 or 535 CE, formed a 7-km-wide caldera. Remnants of this ancestral volcano are preserved in Verlaten and Lang Islands; subsequently Rakata, Danan, and Perbuwatan volcanoes were formed, coalescing to create the pre-1883 Krakatau Island. Caldera collapse during the catastrophic 1883 eruption destroyed Danan and Perbuwatan, and left only a remnant of Rakata. This eruption, the 2nd largest in Indonesia during historical time, caused more than 36,000 fatalities, most as a result of devastating tsunamis that swept the adjacent coastlines of Sumatra and Java. Pyroclastic surges traveled 40 km across the Sunda Strait and reached the Sumatra coast. After a quiescence of less than a half century, the post-collapse cone of Anak Krakatau (Child of Krakatau) was constructed within the 1883 caldera at a point between the former cones of Danan and Perbuwatan. Anak Krakatau has been the site of frequent eruptions since 1927. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0l__8Vm1A$ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKoFi5FQw$> Lewotolok | Lembata Island | 8.274°S, 123.508°E | Summit elev. 1431 m The eruption at Lewotolok continued during 25-31 March according to PVMBG. White-and-gray emissions rose 50-500 m above the summit and drifted W and NW. Ash emissions rose 200-500 m above the summit. On 31 March at 1204 an ash plume rose 800 m above the summit and drifted NW according to a ground observer. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater. Geologic Summary. The Lewotolok (or Lewotolo) stratovolcano occupies the eastern end of an elongated peninsula extending north into the Flores Sea, connected to Lembata (formerly Lomblen) Island by a narrow isthmus. It is symmetrical when viewed from the north and east. A small cone with a 130-m-wide crater constructed at the SE side of a larger crater forms the volcano's high point. Many lava flows have reached the coastline. Eruptions recorded since 1660 have consisted of explosive activity from the summit crater. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0l__8Vm1A$ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKoFi5FQw$> Merapi | Central Java | 7.54°S, 110.446°E | Summit elev. 2910 m BPPTKG reported no significant morphological changes at Merapiâ??s summit lava dome during 25-31 March, though the height of the dome below the SW rim had increased by 4 m. Based on photo analyses, the volume of the SW lava dome had a volume of 1.7 million cubic meters while the central lava dome was 2.6 million cubic meters. Seismicity remained at high levels. As many as 118 lava avalanches originating from the SW dome traveled a maximum of 2.5 km down the Bebeng drainage on the SW flank. On 28 March two pyroclastic flows were recorded on a seismogram that descended 2.5 km SW, one of which occurred at 1509. On 1 April a pyroclastic flow at 1500 descended 1.5 km down the SW flank. Based webcam, satellite, and wind data, the Darwin VAAC reported re-suspended ash that rose to 100 m (300 ft) a.s.l. As many as 37 avalanches were detected, but the distance and direction were not observed. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-5 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. Sources: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lUy6-9QE$ <https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKMclSkfo$>; Darwin Volcanic Ash Advisory Centre (VAAC) https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lkKq2EjU$ <https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKgih5cGc$> Nevados de Chillan | Central Chile | 36.868°S, 71.378°W | Summit elev. 3180 m Based on satellite and webcam data, isolated ash pulses from Nevados de Chillán were reported by the Buenos Aires VAAC during 31 March that rose to 4.9 km (16,000 ft) a.s.l. and drifted N and NNE. Intermittent hotspots were observed in satellite imagery on 1 April. Geologic Summary. The compound volcano of Nevados de Chillán is one of the most active of the Central Andes. Three late-Pleistocene to Holocene stratovolcanoes were constructed along a NNW-SSE line within three nested Pleistocene calderas, which produced ignimbrite sheets extending more than 100 km into the Central Depression of Chile. The dominantly andesitic Cerro Blanco (Volcán Nevado) stratovolcano is located at the NW end of the massif. Volcán Viejo (Volcán Chillán), which was the main active vent during the 17th-19th centuries, occupies the SE end. The Volcán Nuevo lava-dome complex formed during 1906-1945 on the NW flank of Viejo. The Volcán Arrau dome complex was then constructed on the SE side of Volcán Nuevo between 1973 and 1986, and eventually exceeded its height. Smaller domes or cones are present in the 5-km valley between the two major edifices. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC) https://urldefense.com/v3/__http://www.smn.gov.ar/vaac/buenosaires/productos.php__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lV93p0YY$ <https://urldefense.com/v3/__http://www.smn.gov.ar/vaac/buenosaires/productos.php__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKFKDJI20$> Pavlof | Alaska Peninsula, Alaska | 55.417°N, 161.894°W | Summit elev. 2493 m AVO reported that weak eruptive activity was ongoing at Pavlof during 30 March through 4 April, and seismic tremor persisted. Weak explosive activity was detected during 31 March and 2-3 April with low-level plumes visible in the mornings, though satellite and webcam views were mostly obscured by clouds. During 3-4 April elevated surface temperatures were detected in satellite images despite the cloudy weather. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange. Geologic Summary. The most active volcano of the Aleutian arc, Pavlof is a 2519-m-high Holocene stratovolcano that was constructed along a line of vents extending NE from the Emmons Lake caldera. Pavlof and its twin volcano to the NE, 2142-m-high Pavlof Sister, form a dramatic pair of symmetrical, glacier-covered stratovolcanoes that tower above Pavlof and Volcano bays. A third cone, Little Pavlof, is a smaller volcano on the SW flank of Pavlof volcano, near the rim of Emmons Lake caldera. Unlike Pavlof Sister, Pavlof has been frequently active in historical time, typically producing Strombolian to Vulcanian explosive eruptions from the summit vents and occasional lava flows. The active vents lie near the summit on the north and east sides. The largest historical eruption took place in 1911, at the end of a 5-year-long eruptive episode, when a fissure opened on the N flank, ejecting large blocks and issuing lava flows. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lZ_oApVc$ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKnd7MHag$> Popocatepetl | Mexico | 19.023°N, 98.622°W | Summit elev. 5393 m CENAPRED reported that the eruption at Popocatépetl continued during 30 March through 5 April. Each day there were 11-29 diffuse gas-and-steam emissions with ash rising from the crater and drifting S, E, NE, and SE. Based on webcam, satellite and wind models, the Washington VAAC reported ash plumes that rose to 7.3 km (24,000 ft) a.s.l. that drifted E and SE. A moderate explosion was recorded at 2022 on 29 March, resulting in light ashfall in San Pedro Benito Juárez, a municipality of Atlixco. Three volcano-tectonic (VT) earthquakes were recorded on 30 March at 1129, 1146, and 1514. Intermittent VT earthquakes continued during the week. The Alert Level remained at Yellow, Phase Two (the middle level on a three-color scale). Geologic Summary. Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, rises 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 400 x 600 m wide crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano. At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas to the south. The modern volcano was constructed south of the late-Pleistocene to Holocene El Fraile cone. Three major Plinian eruptions, the most recent of which took place about 800 CE, have occurred since the mid-Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since Pre-Columbian time. Sources: Centro Nacional de Prevencion de Desastres (CENAPRED) https://urldefense.com/v3/__https://www.gob.mx/cenapred__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lbXfcVY0$ <https://urldefense.com/v3/__https://www.gob.mx/cenapred__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKUXHgAhk$>; Washington Volcanic Ash Advisory Center (VAAC) https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lmFFcU28$ <https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKRoQ9EPI$> Reventador | Ecuador | 0.077°S, 77.656°W | Summit elev. 3562 m IG reported that a high level of activity continued at Reventador during 30 March through 5 April, though cloudy weather conditions sometimes prevented visual observations. Gas-and-ash plumes, often observed multiple times a day with the webcam or reported by the Washington VAAC, rose as high as 4.6 km (15,000 ft) a.s.l. and drifted mainly NW, W, and SW. As many as 68 daily explosions were detected, in addition to long-period (LP) and emission tremors. Daily thermal anomalies were also reported. On clear weather nights, incandescence could be observed in the upper part of the E flank of the volcano. Blocks were recorded rolling 400 m below the crater on all flanks during 4 April, in addition to the incandescence in the crater. Geologic Summary. Reventador is the most frequently active of a chain of Ecuadorian volcanoes in the Cordillera Real, well east of the principal volcanic axis. The forested, dominantly andesitic Volcán El Reventador stratovolcano rises to 3562 m above the jungles of the western Amazon basin. A 4-km-wide caldera widely breached to the east was formed by edifice collapse and is partially filled by a young, unvegetated stratovolcano that rises about 1300 m above the caldera floor to a height comparable to the caldera rim. It has been the source of numerous lava flows as well as explosive eruptions that were visible from Quito in historical time. Frequent lahars in this region of heavy rainfall have constructed a debris plain on the eastern floor of the caldera. The largest historical eruption took place in 2002, producing a 17-km-high eruption column, pyroclastic flows that traveled up to 8 km, and lava flows from summit and flank vents. Source: Instituto GeofÃsico-Escuela Politécnica Nacional (IG) https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lAzCmeKI$ <https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKN_U3w-w$> Rincon de la Vieja | Costa Rica | 10.83°N, 85.324°W | Summit elev. 1916 m OVSICORI-UNA reported that 10 eruptive events at Rincón de la Vieja had been recorded since 15 March, one of which was detected on 27 March. Between 28 and 29 March a swarm of long-period earthquakes were detected. On 4 April at 1042 an eruption that lasted 1.5 minutes produced a plume, but the height was not observed due to weather conditions. Geologic Summary. Rincón de la Vieja, the largest volcano in NW Costa Rica, is a remote volcanic complex in the Guanacaste Range. The volcano consists of an elongated, arcuate NW-SE-trending ridge constructed within the 15-km-wide early Pleistocene GuachipelÃn caldera, whose rim is exposed on the south side. Sometimes known as the "Colossus of Guanacaste," it has an estimated volume of 130 km3 and contains at least nine major eruptive centers. Activity has migrated to the SE, where the youngest-looking craters are located. The twin cone of Santa MarÃa volcano, the highest peak of the complex, is located at the eastern end of a smaller, 5-km-wide caldera and has a 500-m-wide crater. A Plinian eruption producing the 0.25 km3 RÃo Blanca tephra about 3,500 years ago was the last major magmatic eruption. All subsequent eruptions, including numerous historical eruptions possibly dating back to the 16th century, have been from the prominent active crater containing a 500-m-wide acid lake located ENE of Von Seebach crater. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lXBIINh4$ <https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKypaqglU$> Ruapehu | North Island (New Zealand) | 39.28°S, 175.57°E | Summit elev. 2797 m On 28 March and 5 April GeoNet reported that unrest continued at Ruapehu with elevated levels of tremor and increasing crater lake water temperatures from 32 degrees Celsius to 36 degrees Celsius. The Volcanic Alert Level remained at 2 (on a scale from 0-5) and the Aviation Color Code was raised to Yellow on 28 March. Geologic Summary. Ruapehu, one of New Zealand's most active volcanoes, is a complex stratovolcano constructed during at least four cone-building episodes dating back to about 200,000 years ago. The dominantly andesitic 110 km3 volcanic massif is elongated in a NNE-SSW direction and surrounded by another 100 km3 ring plain of volcaniclastic debris, including the NW-flank Murimoto debris-avalanche deposit. A series of subplinian eruptions took place between about 22,600 and 10,000 years ago, but pyroclastic flows have been infrequent. The broad summait area and flank contain at least six vents active during the Holocene. Frequent mild-to-moderate explosive eruptions have been recorded from the Te Wai a-Moe (Crater Lake) vent, and tephra characteristics suggest that the crater lake may have formed as recently as 3,000 years ago. Lahars resulting from phreatic eruptions at the summit crater lake are a hazard to a ski area on the upper flanks and lower river valleys. Source: GeoNet https://urldefense.com/v3/__http://www.geonet.org.nz/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lb4wvlmc$ <https://urldefense.com/v3/__http://www.geonet.org.nz/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpK6bJPHU4$> Sangay | Ecuador | 2.005°S, 78.341°W | Summit elev. 5286 m IG reported that the eruption at Sangay continued during 30 March through 5 April. Weather clouds and rain often prevented visual and webcam observations, though daily gas-and-ash plumes that rose to 6.7 km (22,000 ft) a.s.l. and drifted W, SW, WSW, and NW were identified in satellite images by the Washington VAAC or in webcam views. As many as 96 daily explosions were detected along with frequent long-period events and emission tremors. Daily thermal anomalies were also visible in satellite data. Incandescent material was visible on the flanks in webcam imagery on clear weather days. Geologic Summary. The isolated Sangay volcano, located east of the Andean crest, is the southernmost of Ecuador's volcanoes and its most active. The steep-sided, glacier-covered, dominantly andesitic volcano grew within horseshoe-shaped calderas of two previous edifices, which were destroyed by collapse to the east, producing large debris avalanches that reached the Amazonian lowlands. The modern edifice dates back to at least 14,000 years ago. It towers above the tropical jungle on the east side; on the other sides flat plains of ash have been sculpted by heavy rains into steep-walled canyons up to 600 m deep. The earliest report of a historical eruption was in 1628. More or less continuous eruptions were reported from 1728 until 1916, and again from 1934 to the present. The almost constant activity has caused frequent changes to the morphology of the summit crater complex. Sources: Instituto GeofÃsico-Escuela Politécnica Nacional (IG) https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lAzCmeKI$ <https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKN_U3w-w$>; Washington Volcanic Ash Advisory Center (VAAC) https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lmFFcU28$ <https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKRoQ9EPI$> Santa Maria | Southwestern Guatemala | 14.757°N, 91.552°W | Summit elev. 3745 m INSIVUMEH reported that the eruption at Santa MarÃaâ??s Santiaguito lava-dome complex continued during 30 March through 5 April. Incandescence from Caliente crater and the lava flows on the W and SW flanks were visible during the night and early morning, accompanied by weak-to-moderate block-and-ash avalanches along its path down the W, SW, and S flanks that reached the base of the dome. The avalanches generated ash plumes that drifted W. Fine ashfall occurred near the volcano on 3 April, including in San Marcos (8 km SW) and Loma Linda Palajunoj (7 km SW). The smell of sulfur was sometimes detected in Las Marias. Geologic Summary. Symmetrical, forest-covered Santa MarÃa volcano is part of a chain of large stratovolcanoes that rise above the Pacific coastal plain of Guatemala. The sharp-topped, conical profile is cut on the SW flank by a 1.5-km-wide crater. The oval-shaped crater extends from just below the summit to the lower flank, and was formed during a catastrophic eruption in 1902. The renowned Plinian eruption of 1902 that devastated much of SW Guatemala followed a long repose period after construction of the large basaltic-andesite stratovolcano. The massive dacitic Santiaguito lava-dome complex has been growing at the base of the 1902 crater since 1922. Compound dome growth at Santiaguito has occurred episodically from four vents, with activity progressing W towards the most recent, Caliente. Dome growth has been accompanied by almost continuous minor explosions, with periodic lava extrusion, larger explosions, pyroclastic flows, and lahars. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lFDB_Xng$ <https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!LsepKq7PfrBYBxlO-IFdVh9DBbe52XmYAyGdg1yOOUtnVi2x53lLwPpKaW3eIiQ$> Sao Jorge | Azores | 38.65°N, 28.08°W | Summit elev. 1053 m A seismic swarm beneath the W half of São Jorge began at 1605 on 19 March, with earthquakes along the Manadas volcanic fissure system between Velas (S side of the island) and Fajã do Ouvidor (N coast). On 31 March there were 714 seismic events detected, according to a preliminary analysis of seismic records. As the week progressed, the number of daily events fluctuated from 397 on 1 April to 592 on 5 April; magnitudes were relatively low. The Alert Level remained at V4 (on a scale of V0-V6). Geologic Summary. The dominantly basaltic São Jorge Island is 55 km long and 6.5 km wide. It was formed by fissure eruptions beginning in the eastern part of the island. The western two-thirds of the island contains youthful, fissure-fed lava flows resembling those on neighboring Pico Island. Lava effused from three locations above the south-central coast during 1580, producing flows that reached the ocean. In 1808 a series of explosions took place from vents along the south-central crest of the island; one of the vents produced a lava flow that reached the southern coast. Submarine eruptions have also been reported on several occasions from a submarine ridge to the SE. The 1964 event offshore W of Velas was considered "probable" by Madiera and Brum da Silveira (2003), who also provided 14C dates for several other Holocene eruptions. Source: Centro de Informação e Vigilância Sismovulcânica dos Açores (CIVISA) https://urldefense.com/v3/__http://www.ivar.azores.gov.pt/civisa/Paginas/homeCIVISA.aspx__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0l4o5pUiY$ Semeru | Eastern Java | 8.108°S, 112.922°E | Summit elev. 3657 m PVMBG reported that the eruption at Semeru continued during 25-31 March. Activity included a pyroclastic flow, ash plumes that rose 300-700 m and drifted mainly N and NW, and gas-and-steam emissions reaching 200-300 m above the summit. Ground observers, webcam images, and satellite data detected ash plumes that rose to 4.3 km (14,000 ft) a.s.l. and drifted N and W, according to MAGMA Indonesia and the Darwin VAAC. Avalanches were reported on 1 April. On 3 April a strong thermal anomaly was detected in infrared satellite imagery. The Alert Level remained at 3 (on a scale of 1-4). The public was warned to stay at least 500 m away from Kobokan drainages within 17 km of the summit, along with other drainages originating on Semeru, 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. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0l__8Vm1A$ ; Darwin Volcanic Ash Advisory Centre (VAAC) https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lkKq2EjU$ Semisopochnoi | Aleutian Islands (USA) | 51.93°N, 179.58°E | Summit elev. 1221 m AVO reported that low-level eruptive activity at Semisopochnoi's North Cerberus cone continued during 30 March-4 April. Periods of seismic tremor and occasional small explosions were detected daily in seismic and regional infrasound data. Daily minor ash emissions rose no higher than 3 km (10,000 ft) a.s.l. and occasional steam emissions were visible in webcam and satellite images; clouds sometimes prevented satellite views. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch. Geologic Summary. Semisopochnoi, the largest subaerial volcano of the western Aleutians, is 20 km wide at sea level and contains an 8-km-wide caldera. It formed as a result of collapse of a low-angle, dominantly basaltic volcano following the eruption of a large volume of dacitic pumice. The high point of the island is Anvil Peak, a double-peaked late-Pleistocene cone that forms much of the island's northern part. The three-peaked Mount Cerberus was constructed within the caldera during the Holocene. Each of the peaks contains a summit crater; lava flows on the N flank of Cerberus appear younger than those on the south side. Other post-caldera volcanoes include the symmetrical Sugarloaf Peak SSE of the caldera and Lakeshore Cone, a small cinder cone at the edge of Fenner Lake in the NE part of the caldera. Most documented eruptions have originated from Cerberus, although Coats (1950) considered that both Sugarloaf and Lakeshore Cone could have been recently active. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lZ_oApVc$ Sheveluch | Central Kamchatka (Russia) | 56.653°N, 161.36°E | Summit elev. 3283 m KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 26 March through 1 April. The lava dome continued to grow and strong fumarolic activity, incandescence, and avalanches accompanied this activity. 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 1300 km3 volcano is one of Kamchatka's largest and most active volcanic structures. 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 dot its outer flanks. The Molodoy Shiveluch lava dome complex was constructed during the Holocene within the large horseshoe-shaped caldera; Holocene lava dome extrusion also took place on the flanks of Stary Shiveluch. At least 60 large eruptions have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. 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) https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lDQv1HB8$ Sirung | Pantar Island | 8.508°S, 124.13°E | Summit elev. 862 m PVMBG reported that white emissions rose 10-50 m above the summit of Sirung and drifted NE, E, and SE. Seismicity was relatively low and showed a consistent decrease since July 2021. As a result, the Alert Level was lowered to 1 (on a scale of 1-4) at 1800 on 1 April. Geologic Summary. Sirung volcano is located at the NE end of a 14-km-long line of volcanic centers that form a peninsula at the southern end of Pantar Island. The volcano is truncated by a 2-km-wide caldera whose floor often contains one or more small lakes. Much of the volcano is constructed of basaltic lava flows, and the Gunung Sirung lava dome forms the high point on the caldera's western rim. A number of phreatic eruptions have occurred from vents within the caldera during the 20th century. Forested Gunung Topaki, the high point of the volcanic chain, lies at the SW end and contains a symmetrical summit crater. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0l__8Vm1A$ Suwanosejima | Ryukyu Islands (Japan) | 29.638°N, 129.714°E | Summit elev. 796 m JMA reported that eruptive activity continued to be recorded at Suwanosejima's Ontake Crater during 29 March through 4 April. As many as 122 explosions were recorded, and crater incandescence was visible nightly. Eruption plumes rose as high as 2.8 km above the crater rim and ejected blocks as far as 900 m from the crater. Ashfall was reported in Toshima village (3.5 km SSW). The Alert Level remained at 3 and the public was warned to stay 2 km away from the crater. Geologic Summary. The 8-km-long, spindle-shaped island of Suwanosejima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two historically active summit craters. The summit is truncated by a large breached crater extending to the sea on the east flank that was formed by edifice collapse. Suwanosejima, one of Japan's most frequently active volcanoes, was in a state of intermittent strombolian activity from Otake, the NE summit crater, that began in 1949 and lasted until 1996, after which periods of inactivity lengthened. The largest historical eruption took place in 1813-14, when thick scoria deposits blanketed 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 the horseshoe-shaped Sakuchi caldera, which extends 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) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lXiyqkJE$ Taal | Luzon (Philippines) | 14.002°N, 120.993°E | Summit elev. 311 m PHIVOLCS reported that hot volcanic fluids circulated and upwelled in Taalâ??s Main Crater lake during 30 March through 6 April, producing plumes that rose as high as 2 km above the lakeâ??s surface and drifted SW. Sulfur dioxide emissions averaged 265-7,856 tonnes/day during the week. Tremor events persisted daily until 5 April. Three phreatomagmatic bursts from the Main Crater were detected at 1039, 1047, and 1055, based on seismic data and webcam images, which produced plumes 500-900 m tall that drifted SW. PHIVOLCS noted that Alert Level 3 (magmatic unrest) means that there has been a magmatic intrusion and evacuation of high-risk barangays is recommended. Geologic Summary. Taal is one of the most active volcanoes in the Philippines and has produced some of its most powerful historical eruptions. Though not topographically prominent, its prehistorical eruptions have greatly changed the landscape of SW Luzon. The 15 x 20 km Talisay (Taal) caldera is largely filled by Lake Taal, whose 267 km2 surface lies only 3 m above sea level. The maximum depth of the lake is 160 m, and several eruptive centers lie submerged beneath the lake. The 5-km-wide Volcano Island in north-central Lake Taal is the location of all historical eruptions. The island is composed of coalescing small stratovolcanoes, tuff rings, and scoria cones that have grown about 25% in area during historical time. Powerful pyroclastic flows and surges from historical eruptions have caused many fatalities. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS) https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lh0JmNDI$ Telica | Sierra de los Marrabios | 12.606°N, 86.84°W | Summit elev. 1036 m Based on webcam images, the Washington VAAC reported that on 29 March ash emissions at Telica rose as high as 1.5 km (5,000 ft) a.s.l. and drifted W. Geologic Summary. Telica, one of Nicaragua's most active volcanoes, has erupted frequently since the beginning of the Spanish era. This volcano group consists of several interlocking cones and vents with a general NW alignment. Sixteenth-century eruptions were reported at symmetrical Santa Clara volcano at the SW end of the group. However, its eroded and breached crater has been covered by forests throughout historical time, and these eruptions may have originated from Telica, whose upper slopes in contrast are unvegetated. The steep-sided cone of Telica is truncated by a 700-m-wide double crater; the southern crater, the source of recent eruptions, is 120 m deep. El Liston, immediately E, has several nested craters. The fumaroles and boiling mudpots of Hervideros de San Jacinto, SE of Telica, form a prominent geothermal area frequented by tourists, and geothermal exploration has occurred nearby. Source: Washington Volcanic Ash Advisory Center (VAAC) https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lmFFcU28$ Whakaari/White Island | North Island (New Zealand) | 37.52°S, 177.18°E | Summit elev. 294 m On 4 April GeoNet reported that the ash emissions at Whakaari/White Island had not been observed since late February 2022; gas temperatures had declined to below 300 degrees Celsius. As a result, the Volcanic Alert Level was lowered to 1 and the Aviation Color Code was lowered to Green. Geologic Summary. The uninhabited Whakaari/White Island is the 2 x 2.4 km emergent summit of a 16 x 18 km submarine volcano in the Bay of Plenty about 50 km offshore of North Island. The island consists of two overlapping andesitic-to-dacitic stratovolcanoes. The SE side of the crater is open at sea level, with the recent activity centered about 1 km from the shore close to the rear crater wall. Volckner Rocks, sea stacks that are remnants of a lava dome, lie 5 km NW. Descriptions of volcanism since 1826 have included intermittent moderate phreatic, phreatomagmatic, and Strombolian eruptions; activity there also forms a prominent part of Maori legends. The formation of many new vents during the 19th and 20th centuries caused rapid changes in crater floor topography. Collapse of the crater wall in 1914 produced a debris avalanche that buried buildings and workers at a sulfur-mining project. Explosive activity in December 2019 took place while tourists were present, resulting in many fatalities. The official government name Whakaari/White Island is a combination of the full Maori name of Te Puia o Whakaari ("The Dramatic Volcano") and White Island (referencing the constant steam plume) given by Captain James Cook in 1769. Source: GeoNet https://urldefense.com/v3/__http://www.geonet.org.nz/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lb4wvlmc$ Wolf | Isla Isabela (Galapagos) | 0.02°N, 91.35°W | Summit elev. 1710 m IG reported that the eruption at Wolf continued during 30 March through 5 April. Daily thermal alert counts, as many as around 145, indicated active and advancing lava flows. Geologic Summary. Wolf, the highest volcano of the Galápagos Islands, straddles the equator at the north end of the archipelago's largest island, Isabela. The 1710-m-high edifice has steeper slopes than most other Isabela volcanoes, reaching angles up to 35 degrees. A 6 x 7 km caldera, at 700 m one of the deepest of the Galápagos Islands, is located at the summit. A prominent bench on the west side of the caldera rises 450 above the caldera floor, much of which is covered by a lava flow erupted in 1982. Radial fissures concentrated along diffuse rift zones extend down the north, NW, and SE flanks, and submarine vents lie beyond the north and NW fissures. Similar unvegetated flows originating from a circumferential chain of spatter and scoria cones on the eastern caldera rim drape the forested flanks to the sea. The proportion of aa lava flows at Volcán Wolf exceeds that of other Galápagos volcanoes. An eruption in in 1797 was the first documented historical eruption in the Galápagos Islands. Source: Instituto GeofÃsico-Escuela Politécnica Nacional (IG) https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lAzCmeKI$ Yasur | Vanuatu | 19.532°S, 169.447°E | Summit elev. 361 m On 31 March the Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a high level of â??major unrest,â?? as defined by the Alert Level 2 status (the middle level on a scale of 0-4). Ash-and-gas emissions and loud explosions continued to be recorded, with bombs falling in and around the crater. The public was reminded not to enter the restricted area within 600 m around the cone, defined by Danger Zone A on the hazard map. Geologic Summary. Yasur, the best-known and most frequently visited of the Vanuatu volcanoes, has been in more-or-less continuous Strombolian and Vulcanian activity since Captain Cook observed ash eruptions in 1774. This style of activity may have continued for the past 800 years. Located at the SE tip of Tanna Island, this mostly unvegetated pyroclastic cone has a nearly circular, 400-m-wide summit crater. The active cone is largely contained within the small Yenkahe caldera, and is the youngest of a group of Holocene volcanic centers constructed over the down-dropped NE flank of the Pleistocene Tukosmeru volcano. The Yenkahe horst is located within the Siwi ring fracture, a 4-km-wide, horseshoe-shaped caldera associated with eruption of the andesitic Siwi pyroclastic sequence. Active tectonism along the Yenkahe horst accompanying eruptions has raised Port Resolution harbor more than 20 m during the past century. Source: Vanuatu Meteorology and Geo-Hazards Department (VMGD) https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lROHxFB8$ 1-1-1-1-1-1-1-1-1-1-1-1-1-1 ============================================================== 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 - https://urldefense.com/v3/__http://pdx.edu/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0l_MqNHfg$ GVP - https://urldefense.com/v3/__http://www.volcano.si.edu/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0loq7GaIo$ IAVCEI - https://urldefense.com/v3/__https://www.iavceivolcano.org/__;!!IKRxdwAv5BmarQ!IseiJZpUybj_TGm66f2HDfMdd3hrQYGK8ezcFTuBzhZAw0863ore9z0lH0bv5Kk$ 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 - 6 Apr 2022 to 7 Apr 2022 (#2022-38) ***********************************************************
