3-3-3-3-3-3-3-3-3-3-3-3-3 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 4-10 September 2024 Sally Sennert - Weekly Report Editor (kuhns@xxxxxx) URL: https://volcano.si.edu/reports_weekly.cfm <https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH36y_MZEw$> New Activity/Unrest: Kanlaon, Philippines | Karymsky, Eastern Kamchatka (Russia) | Kikai, Ryukyu Islands (Japan) | Klyuchevskoy, Central Kamchatka (Russia) | Reykjanes, Reykjanes Peninsula | Whakaari/White Island, North Island (New Zealand) Ongoing Activity: Aira, Kyushu (Japan) | Dukono, Halmahera | Ebeko, Paramushir Island (Russia) | Fuego, South-Central Guatemala | Great Sitkin, Andreanof Islands (USA) | Ibu, Halmahera | Lewotobi, Flores Island | Merapi, Central Java | Sangay, Ecuador | Santa Maria, Southwestern Guatemala | Semeru, Eastern Java | Sheveluch, Central Kamchatka (Russia) | Suwanosejima, Ryukyu Islands (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 Kanlaon | Philippines | 10.4096°N, 123.13°E | Summit elev. 2422 m PHIVOLCS issued special notices for Kanlaon noting periods of increased seismicity and continuing high levels sulfur dioxide gas emissions. The seismic network detected 288 volcano-tectonic earthquakes from 2030 on 9 September to 1100 on 10 September that were located at depths of 0-9 km beneath the NE flank. The strongest events were classified at Intensity II and felt in some barangays (neighborhoods) of Canlaon City, 8 km SSE, Negros Oriental. Rumbling sounds were reported by residents of Bago City and a strong sulfur odor was reported in a few barangays in the cities of Bago (30 km NW), La Carlota (14 km W), and Canlaon. According to a news article the intense seismicity prompted the local Canlaon City government to order a mandatory evacuation of the Permanent Danger Zone, defined as a 4 km radius from the summit, as a precautionary measure. About 91 families (301 people) moved to evacuation centers. Summit emissions of sulfur dioxide measured with a Flyspec instrument averaged 9,985 tonnes/day (t/d) on 10 September, the highest ever recorded at the volcano. Sulfur odors were reported in the barangays of Ilijan (Bago), Ara-al and San Miguel (La Carlota), and in Masulog, Linothangan, and Pula (Canlaon). A steam-and-gas plume rose 1 km above the summit and drifted SE. Another record high for sulfur dioxide emissions was recorded on 11 September with an average of 11,556 t/d. Residents reported sulfur odors in areas downwind including San Miguel, Masulog, Pula, Codcod (San Carlos City), and Inolingan (Moises Padilla). A news report noted that both public and private schools suspended classes in four barangays. Elevated sulfur dioxide gas fluxes had been recorded in 2024 with an average of 1,273 t/d prior to the 3 June eruption; afterward the eruption emissions were averaging 3,468 t/d. The Alert Level remained at 2 (on a scale of 0-5) and PHIVOLCS reminded the public to remain outside of the 4-km-radius Permanent Danger Zone and warned pilots 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. Sources: Philippine Institute of Volcanology and Seismology (PHIVOLCS) http://www.phivolcs.dost.gov.ph/ <https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH244Zp7tQ$> ; Philippine News Agency (PNA) https://www.pna.gov.ph/articles/1232991 <https://urldefense.com/v3/__https://www.pna.gov.ph/articles/1232991__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH04Q0LK4w$> ; Philippine News Agency (PNA) https://www.pna.gov.ph/articles/1233106 <https://urldefense.com/v3/__https://www.pna.gov.ph/articles/1233106__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH3AuIUbhA$> Karymsky | Eastern Kamchatka (Russia) | 54.049°N, 159.443°E | Summit elev. 1513 m KVERT reported moderate levels of activity at Karymsky during 29 August-6 September. A thermal anomaly over the volcano was identified in satellite images during 29-30 August and 3-4 September. A series of six significant explosions on 30 August generated ash plumes that rose as high as 7 km (23,000 ft) a.s.l. and drifted 150 km ENE. The Aviation Color Code was briefly raised to Red (the highest level on a four-color scale) and then lowered back to Orange that same day. Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH3EMW-UaQ$> Kikai | Ryukyu Islands (Japan) | 30.793°N, 130.305°E | Summit elev. 704 m JMA reported that no activity at Iodake Crater located at Satsuma Iwo-jima, a subaerial part of Kikaiâ??s NW caldera rim, was detected after the 1 and 3 September eruptive events. Crater incandescence continued to be observed at night. The Alert Level remained at 2 (on a 5-level scale), and residents were warned to stay 500 m away from Iodake Crater. Geologic Summary. Multiple eruption centers have exhibited recent activity at Kikai, a mostly submerged, 19-km-wide caldera near the northern end of the Ryukyu Islands south of Kyushu. It was the source of one of the world's largest Holocene eruptions about 6,300 years ago when rhyolitic pyroclastic flows traveled across the sea for a total distance of 100 km to southern Kyushu, and ashfall reached the northern Japanese island of Hokkaido. The eruption devastated southern and central Kyushu, which remained uninhabited for several centuries. Post-caldera eruptions formed Iodake (or Iwo-dake) lava dome and Inamuradake scoria cone, as well as submarine lava domes. Recorded eruptions have occurred at or near Satsuma-Iojima (also known as Tokara-Iojima), a small 3 x 6 km island forming part of the NW caldera rim. Showa-Iojima lava dome (also known as Iojima-Shinto), a small island 2 km E of Satsuma-Iojima, was formed during submarine eruptions in 1934 and 1935. Mild-to-moderate explosive eruptions have occurred during the past few decades from Iodake, a rhyolitic lava dome at the eastern end of Satsuma-Iojima. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH1EVo6gAg$> Klyuchevskoy | Central Kamchatka (Russia) | 56.056°N, 160.642°E | Summit elev. 4754 m KVERT lowered the Aviation Color Code for Klyuchevskoy to Green (the lowest level on a four-color scale) at 2300 on 7 September, noting that seismicity had decreased to background levels and no signs of eruptive activity were identified in satellite data. Dates and times are in UTC; specific events are in local time where noted. Geologic Summary. Klyuchevskoy is the highest and most active volcano on the Kamchatka Peninsula. Since its origin about 6,000 years ago, this symmetrical, basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. It rises above a saddle NE of Kamen volcano and lies SE of the broad Ushkovsky massif. More than 100 flank eruptions have occurred during approximately the past 3,000 years, with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks of the conical volcano between 500 and 3,600 m elevation. Eruptions recorded since the late 17th century have resulted in frequent changes to the morphology of the 700-m-wide summit crater. These eruptions over the past 400 years have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH3EMW-UaQ$> Reykjanes | Reykjanes Peninsula | 63.817°N, 22.717°W | Summit elev. 140 m IMO reported that the eruption between Stóra-Skógfell and Sundhnúkur, within the Reykanes volcanic system, had ended after 14 days. During 1-5 September activity was concentrated at two main vents located at the N end of the fissure but the intensity of the activity had significantly decreased. Seismic activity had also decreased along with gas emissions. Lava continued to slowly move N, thickening the flow field. Activity at the vents was no longer visible by the evening of 5 September. On 6 September IMO lowered the Aviation Color Code to Yellow (the second lowest level on a four-color scale) noting that the eruption was over. Volcanic tremor had decreased almost to pre-eruptive levels. GPS data indicated that inflation at Svartsengi had resumed. Geologic Summary. The Reykjanes volcanic system at the SW tip of the Reykjanes Peninsula, where the Mid-Atlantic Ridge rises above sea level, comprises a broad area of postglacial basaltic crater rows and small shield volcanoes. The submarine Reykjaneshryggur volcanic system is contiguous with and is considered part of the Reykjanes volcanic system, which is the westernmost of a series of four closely-spaced en-echelon fissure systems that extend diagonally across the Reykjanes Peninsula. Most of the subaerial part of the system (also known as the Reykjanes/Svartsengi volcanic system) is covered by Holocene lavas. Subaerial eruptions have occurred in historical time during the 13th century at several locations on the NE-SW-trending fissure system, and numerous submarine eruptions dating back to the 12th century have been observed during historical time, some of which have formed ephemeral islands. Basaltic rocks of probable Holocene age have been recovered during dredging operations, and tephra deposits from earlier Holocene eruptions are preserved on the nearby Reykjanes Peninsula. Sources: Icelandic Meteorological Office (IMO) http://en.vedur.is/ <https://urldefense.com/v3/__http://en.vedur.is/__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH1EDVm-gA$> ; National Commissioner of the Icelandic Police (NCIP) Department of Civil Protection and Emergency Management http://www.almannavarnir.is/ <https://urldefense.com/v3/__http://www.almannavarnir.is/__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH0fwo9IPA$> Whakaari/White Island | North Island (New Zealand) | 37.52°S, 177.18°E | Summit elev. 294 m The Wellington VAAC reported ongoing low-level ash emissions from Whakaari/White Island during 4-10 September based on satellite data, webcam views, and weather models. The plumes rose 0.9-1.5 km (3,000-5,000 ft) a.s.l. and drifted N, NE, E, and SE. Views were sometimes obscured by weather clouds. Geologic Summary. The uninhabited Whakaari/White Island is the 2 x 2.4 km emergent summit of a 16 x 18 km submarine volcano in the Bay of Plenty about 50 km offshore of North Island. The island consists of two overlapping andesitic-to-dacitic stratovolcanoes. The SE side of the crater is open at sea level, with the recent activity centered about 1 km from the shore close to the rear crater wall. Volckner Rocks, sea stacks that are remnants of a lava dome, lie 5 km NW. Descriptions of volcanism since 1826 have included intermittent moderate phreatic, phreatomagmatic, and Strombolian eruptions; activity there also forms a prominent part of Maori legends. The formation of many new vents during the 19th and 20th centuries caused rapid changes in crater floor topography. Collapse of the crater wall in 1914 produced a debris avalanche that buried buildings and workers at a sulfur-mining project. Explosive activity in December 2019 took place while tourists were present, resulting in many fatalities. The official government name Whakaari/White Island is a combination of the full Maori name of Te Puia o Whakaari ("The Dramatic Volcano") and White Island (referencing the constant steam plume) given by Captain James Cook in 1769. Source: Wellington Volcanic Ash Advisory Center (VAAC) http://vaac.metservice.com/ <https://urldefense.com/v3/__http://vaac.metservice.com/__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH0ZVTW8tA$> Ongoing Activity Aira | Kyushu (Japan) | 31.5772°N, 130.6589°E | Summit elev. 1117 m JMA reported ongoing eruptive activity at Minamidake Crater (Aira Calderaâ??s Sakurajima volcano) during 2-9 September. Nighttime crater incandescence was visible in webcam images during dark hours. Very small eruptive events occasionally occurred. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 1 km away from both craters. Geologic Summary. The Aira caldera in the northern half of Kagoshima Bay contains the post-caldera Sakurajima volcano, one of Japan's most active. Eruption of the voluminous Ito pyroclastic flow accompanied formation of the 17 x 23 km caldera about 22,000 years ago. The smaller Wakamiko caldera was formed during the early Holocene in the NE corner of the caldera, along with several post-caldera cones. The construction of Sakurajima began about 13,000 years ago on the southern rim and built an island that was joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kitadake summit cone ended about 4,850 years ago, after which eruptions took place at Minamidake. Frequent eruptions since the 8th century have deposited ash on the city of Kagoshima, located across Kagoshima Bay only 8 km from the summit. The largest recorded eruption took place during 1471-76. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH1EVo6gAg$> Dukono | Halmahera | 1.6992°N, 127.8783°E | Summit elev. 1273 m PVMBG reported that the eruption at Dukono was ongoing during 4-10 September. Gray-and-white ash plumes that were sometimes dense rose 100-1,200 m above the summit and drifted E, S, and W on most days; white plumes rose as high as 800 m above the summit and drifted E on 4 September. The Alert Level remained at Level 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone. Geologic Summary. Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, have occurred since 1933. During a major eruption in 1550 CE, a lava flow filled in the strait between Halmahera and the N-flank Gunung Mamuya cone. This complex volcano presents a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also been active during historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH0a3MhV7Q$> Ebeko | Paramushir Island (Russia) | 50.686°N, 156.014°E | Summit elev. 1103 m KVERT reported that moderate explosive activity was ongoing at Ebeko during 29 August-6 Septrmber. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E), explosions during 2-5 September generated ash plumes that rose as high as 3 km (10,000 ft) a.s.l. and drifted N. Satellite data indicated that either no activity was observed, or weather conditions prevented views. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are UTC; specific events are in local time where noted. Geologic Summary. The flat-topped summit of the central cone of Ebeko volcano, one of the most active in the Kuril Islands, occupies the northern end of Paramushir Island. Three summit craters located along a SSW-NNE line form Ebeko volcano proper, at the northern end of a complex of five volcanic cones. Blocky lava flows extend west from Ebeko and SE from the neighboring Nezametnyi cone. The eastern part of the southern crater contains strong solfataras and a large boiling spring. The central crater is filled by a lake about 20 m deep whose shores are lined with steaming solfataras; the northern crater lies across a narrow, low barrier from the central crater and contains a small, cold crescentic lake. Historical activity, recorded since the late-18th century, has been restricted to small-to-moderate explosive eruptions from the summit craters. Intense fumarolic activity occurs in the summit craters, on the outer flanks of the cone, and in lateral explosion craters. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH3EMW-UaQ$> Fuego | South-Central Guatemala | 14.473°N, 90.88°W | Summit elev. 3763 m INSIVUMEH reported that eruptive activity continued at Fuego during 3-10 September. Daily explosions were recorded by the seismic network, averaging 3-10 per hour. The explosions generated gas-and-ash plumes that rose as high as 1.1 km above the crater rim and drifted as far as 30 km NW, W, and SW. The explosions ejected incandescent material 100-200 m above the summit on most days and produced avalanches of material that descended the flanks, sometimes reaching vegetated areas. Weak rumbling sounds were reported on most days and shock waves were sometimes detected in local areas. Ashfall was reported on a few of the days in areas downwind including Panimaché I and II (8 km SW), Finca Palo Verde (10 km SW), El Porvenir (10 km S), Santa Sofia (12 km SW), Sangre de Cristo (10 km SW), Morelia (10 km SW), Los Yucales (12 km SW), Yepocápa (8 km NW), and other nearby communities. Ashfall was forecast for areas downwind on some of the other days. During the evening of 19 Septrmber lahars descended the El Jute, Las Lahas, Ceniza, and Zarco drainages, carrying tree branches, trunks, and blocks as large as 1.5 m in diameter. 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. 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!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH2bCCb-qg$> Great Sitkin | Andreanof Islands (USA) | 52.076°N, 176.13°W | Summit elev. 1740 m AVO reported that slow lava effusion continued to feed a thick lava flow in Great Sitkinâ??s summit crater during 4-10 September. Seismicity was low with few small daily earthquakes. Steam rising from the flow was visible in webcam views on 8 September. Weather clouds often obscured views of the summit. 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!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH1Tb_WRmQ$> Ibu | Halmahera | 1.488°N, 127.63°E | Summit elev. 1325 m PVMBG reported that activity at Ibu continued during 4-10 September with multiple eruptive events recorded daily. Daily gray or white-and-gray ash plumes that were sometimes dense generally rose as high as 1.5 km above the summit and drifted in multiple directions. At 1756 on 7 September a dense gray ash plume rose as high as 4 km above the crater rim and drifted W. Some webcam images posted with the reports showed incandescence visible above the crater rim. The Alert Level remained at 3 (the second highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 5 km away from the N crater wall opening. Geologic Summary. The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, has contained several small crater lakes. The 1.2-km-wide outer crater is breached on the N, creating a steep-walled valley. A large cone grew ENE of the summit, and a smaller one to the WSW has fed a lava flow down the W flank. A group of maars is located below the N and W flanks. The first observed and recorded eruption was a small explosion from the summit crater in 1911. Eruptive activity began again in December 1998, producing a lava dome that eventually covered much of the floor of the inner summit crater along with ongoing explosive ash emissions. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH0a3MhV7Q$> Lewotobi | Flores Island | 8.542°S, 122.775°E | Summit elev. 1703 m PVMBG reported that eruptive activity at Lewotobiâ??s Laki-laki volcano continued during 4-10 September mainly from a vent on the upper NW flank. Daily gray or white-and-gray ash plumes that were sometimes dense rose as high as 1.2 km above the summit and drifted SW, W, and NW; only white emissions were visible on 4 September. A webcam image from 0333 on 5 September captured an area of incandescence on the flank and possible lightning in the lower part of the plume. A news article noted that for the past two months operations continued to be suspended at the Frans Seda Maumere Airport (60 km WSW) because ashfall continued to impact the runways. The report also noted that the airport in Ende had been closed for several days. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3 km radius around both Laki-laki and Perempuan craters, 4 km to the NNW and SSE 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. 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!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH0a3MhV7Q$> ; Antara News https://www.antaranews.com/berita/4318535/bandara-di-maumere-sudah-tutup-dua-bulan-akibat-erupsi-gunung-lewotobi <https://urldefense.com/v3/__https://www.antaranews.com/berita/4318535/bandara-di-maumere-sudah-tutup-dua-bulan-akibat-erupsi-gunung-lewotobi__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH1UY_RVsw$> Merapi | Central Java | 7.54°S, 110.446°E | Summit elev. 2910 m BPPTKG reported that the eruption at Merapi (on Java) continued during 30 August-5 September. Seismicity was less intense compared to the previous week. The SW lava dome produced 232 lava avalanches that traveled as far as 1.8 km down the Bebeng drainage on the SW flank. Morphological changes to the SW lava dome were due to continuing effusion and 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!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH2Cw2knOg$> Sangay | Ecuador | 2.005°S, 78.341°W | Summit elev. 5286 m IG-EPN reported that high levels of eruptive activity continued at Sangay during 3-10 September and the seismic network recorded 112-275 daily explosions. Gas-and-ash plumes were visible in webcam and/or satellite images on most days and rose 400-600 m above the summit and drifted mainly W, WSW, and SW. Weather conditions sometimes obscured views; emissions were not visible on 5 September. Incandescent material was ejected 500 m above the summit and descended the SE drainage as far as 500 m during 3-4 September. Incandescence at the summit was visible during 5-7 September, and overnight during 7-8 and 9-10 September incandescent material descended the SE drainage as far as 1.5 km on several occasions. 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!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH1ZCmAi2A$> ; SecretarÃa de Gestión de Riesgos (SGR) http://www.gestionderiesgos.gob.ec/ <https://urldefense.com/v3/__http://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH3Wz751NA$> Santa Maria | Southwestern Guatemala | 14.757°N, 91.552°W | Summit elev. 3745 m INSIVUMEH reported ongoing eruptive activity at Santa Mariaâ??s Santiaguito lava-dome complex during 3-10 September with lava extrusion, block collapses, and avalanches at the Caliente dome complex. Effusion of blocky lava produced block avalanches on the domeâ??s flanks and occasional short pyroclastic flows that descended multiple flanks; the deposits created promontories of unstable material near the top of the 2022 lava flow located in the Zanjón Seco and San Isidro drainages. Incandescence from avalanches of material at the dome as well as explosions was visible during dark hours. Daily explosions (a few per hour) generated gas-and-ash plumes that rose 500-900 m above the summit and drifted mainly N, W, and SW. Ashfall was reported in San Marcos (8 km SW) and Loma Linda Palajunoj (7 km SW) during 5-6 September. Ash fell on the flanks and in surrounding areas during 7-8 September. 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!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH2bCCb-qg$> Semeru | Eastern Java | 8.108°S, 112.922°E | Summit elev. 3657 m PVMBG reported that eruptive activity continued at Semeru during 4-10 September with multiple daily eruptive events recorded by the seismic network. White-and-gray ash plumes that were sometimes dense rose 300-600 m above the summit and drifted SW during 5, 7, and 9-10 September. Emissions were not observed on the other days. Crater incandescence was sometimes visible in webcam images. 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!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH0a3MhV7Q$> Sheveluch | Central Kamchatka (Russia) | 56.653°N, 161.36°E | Summit elev. 3283 m KVERT reported that during 1-6 September lava extrusion likely continued at Sheveluchâ??s â??300 years of RASâ?? dome on the SW flank of Old Sheveluch and at a new vent or dome that formed during the 17-18 August explosive events. Daily thermal anomalies over the domes were identified in satellite images. Explosive activity during 1-2 September generated ash plumes that rose as high as 8 km (26,200 ft) a.s.l. and drifted 1,050 km NE. The plume was detected over the Arctic Ocean during 4-5 September. On 5 September a plume of resuspended ash drifted 95 km E. 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!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH3EMW-UaQ$> Suwanosejima | Ryukyu Islands (Japan) | 29.638°N, 129.714°E | Summit elev. 796 m JMA reported that eruptive activity at Suwanosejima's Ontake Crater continued during 2-9 September and crater incandescence was observed nightly in webcam images. The seismic network recorded 12 explosions and numerous eruptive events. Occasional rumbling and ashfall were reported at the Suwanosejima Branch Office in Toshima village (3.5 km SSW) on unspecified dates. The explosions were recorded at 2027 on 2 September, at 1103 and 2304 on 4 September, at 0425, 1602, and 1736 on 5 September, at 0541, 1938, and 2036 on 6 September, at 2121 on 7 September, at 2144 on 8 September, and at 1728 on 9 September. The explosions generated ash plumes that rose 0.4-1.7 km above the crater rim and drifted NW, W, and SW; details about the last two explosions were unknown. Large blocks were sometimes ejected as far as 600 m from the vent. As many as 11 daily eruptive events were also recorded and produced ash plumes that rose as high as 1.6 km above the crater rim and drifted NW, W, and SW. The Alert Level remained at 2 (on a 5-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!erD__tI6Dc0e2jHM6CzwyXCE7JYtSdkwot1IWuhcE_QfaTfill2-SJDx_kjY4qfA8Cwr8JrrB8pV25kmiH1EVo6gAg$> 3-3-3-3-3-3-3-3-3-3-3-3-3 ============================================================== Volcano Listserv is a collaborative venture among Arizona State University (ASU), Portland State University (PSU), the Global Volcanism Program (GVP) of the Smithsonian Institution's National Museum of Natural History, and the International Association for Volcanology and Chemistry of the Earth's Interior (IAVCEI). 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