11-11-11-11-11-11-11-11-11-11-11-11 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 20-26 November 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!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5q6eMEpQ$> New Activity/Unrest: Ambrym, Vanuatu | Dempo, Indonesia | Lewotobi, Indonesia | Reykjanes, Iceland | Sheveluch, Russia | Ulawun, Papua New Guinea Ongoing Activity: Aira, Japan | Banda Api, Indonesia | Dukono, Indonesia | Ebeko, Russia | Great Sitkin, United States | Ibu, Indonesia | Kanlaon, Philippines | Karymsky, Russia | Kuchinoerabujima, Japan | Manam, Papua New Guinea | Merapi, Indonesia | Nevado del Ruiz, Colombia | Semeru, Indonesia | Suwanosejima, Japan The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday, these reports are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of all of Earth's volcanoes erupting during the week, but rather a summary of activity at volcanoes that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed reports about recent activity are published in issues of the Bulletin of the Global Volcanism Network. Note that many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source. New Activity/Unrest Ambrym | Vanuatu | 16.25°S, 168.12°E | Summit elev. 1334 m The Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported eruptive activity at Ambrym during October and November. In October small steam emissions from both Benbow and Marum craters were visible in webcam images. A low-level thermal anomaly over the volcano was detected in satellite images on 3 October indicating the presence of lava at or near the surface. Low-to-moderate thermal anomalies were identified in satellite images during 1, 2, 5, and 11-12 November. Seismic data confirmed an ongoing volcanic activity. On 12 November interferometry analysis of satellite data indicated magma movement beneath the surface. 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 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 Geohazards Department (VMGD) http://www.geohazards.gov.vu/ <https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5R3ugSvA$> Dempo | Indonesia | 4.016°S, 103.121°E | Summit elev. 3142 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Dempo was recorded at 1338 on 23 November. Jets of dark material were ejected around 200 m above the lakeâ??s surface, mainly to the N. The eruption lasted about four minutes based on the seismic data. According to a news article, there were 68 registered climbers on Dempo when the eruption occurred, though no one was near the summit at the time; the volcano was closed to climbers on 24 November. The Alert Level remained at 2 (on a scale of 1-4), and the public were reminded to stay 1 km away from the crater and as far as 2 km on the N flank. Geologic Summary. Dempo is a stratovolcano that rises above the Pasumah Plain of SE Sumatra. The andesitic complex has two main peaks, Gunung Dempo and Gunung Marapi, constructed near the SE rim of a 3-km-wide amphitheater open to the north. The high point of the older Gunung Dempo crater rim is slightly lower, and lies at the SE end of the summit complex. The taller Marapi cone was constructed within the older crater. Remnants of seven craters are found at or near the summit, with volcanism migrating WNW over time. The active 750 x 1,100 m active crater cuts the NW side of the Marapi cone and contains a 400-m-wide lake at the far NW end. Eruptions recorded since 1817 have been small-to-moderate explosions that produced local ashfall. 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!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5eVu8RGQ$> ; Antara News https://www.antaranews.com/berita/4489141/pvmbg-gunung-dempo-berkabut-pasca-erupsi-pendakian-ditutup-sementara <https://urldefense.com/v3/__https://www.antaranews.com/berita/4489141/pvmbg-gunung-dempo-berkabut-pasca-erupsi-pendakian-ditutup-sementara__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5TUgYmew$> Lewotobi | Indonesia | 8.542°S, 122.775°E | Summit elev. 1703 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity continued at Lewotobi Laki-laki during 20-26 November. Ash plumes rose 1-3 km above the summit and drifted SW, W, and NW on 20 November. Daily ash plumes during the rest of the week rose 600-1,500 m above the summit and drifted SW, W, and NW. A majority of the webcam images posted with the daily reports showed incandescence at the summit. Rumbling was reported during 21-22 and 26 November. As of 2000 on 23 November there were 5,607 people in evacuation centers and another 7,363 people staying in other locations, according to a news article. Members of the Indonesian Army were sent to seven affected villages to assist with clean up and recovery. BNPB confirmed that at least 422 temporary housing units were to be built within the next two months to accommodate displaced families. The Alert Level remained at 4 (on a scale of 1-4). Residents were prohibited within a radius of 7 km from the center of Laki-laki and within a radius of 8 km on the SW, W, and NW flanks. 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!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5eVu8RGQ$> ; Antara News https://www.antaranews.com/berita/4488793/gunung-lewotobi-kembali-erupsi-pada-minggu-pagi <https://urldefense.com/v3/__https://www.antaranews.com/berita/4488793/gunung-lewotobi-kembali-erupsi-pada-minggu-pagi__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk6LpZdsjg$> ; Antara News https://www.antaranews.com/berita/4487513/tni-ad-pulihkan-desa-terdampak-erupsi-gunung-lewotobi-laki-laki <https://urldefense.com/v3/__https://www.antaranews.com/berita/4487513/tni-ad-pulihkan-desa-terdampak-erupsi-gunung-lewotobi-laki-laki__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk7dnAR9Ig$> ; Antara News https://kupang.antaranews.com/berita/143125/442-unit-hunian-sementara-dibangun-untuk-korban-lewotobi <https://urldefense.com/v3/__https://kupang.antaranews.com/berita/143125/442-unit-hunian-sementara-dibangun-untuk-korban-lewotobi__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk7wyPkm8A$> Reykjanes | Iceland | 63.817°N, 22.717°W | Summit elev. 140 m The Icelandic Meteorological Office (IMO) reported that a new eruption at the Sundhnúkur crater row began in a location between Stóra-Skógfell and Sýlingarfell, within the Reykjanes volcanic system, after a brief period of precursory seismicity. The eruption was the tenth to have occurred on the Reykjanes Peninsula since March 2021 and the seventh in 2024. A small earthquake swarm started at 2230 on 20 November and was followed by pressure changes in boreholes at 2237, both indicative of a dike intrusion. At 2300 IMO raised the Aviation Color Code to Orange (the second highest level on a four-color scale). A NE-SW-trending fissure opened at 2314 and propagated NE. Lava fountains rose along the fissure and lava spread laterally from the fissure to the E and W, though most of the advancement was to the W. IMO raised the Aviation Color Code to Red at 2319 and noted that a volcanic plume rose to 2 km (6,600 ft) a.s.l.; the Aviation Color Code was lowered back to Orange at 2354. According to a news article 50-60 people in GrindavÃk were evacuated along with people at the Blue Lagoon spa and the Svartsengi power station. IMO confirmed at 0004 on 21 November that no ash was detected in the plume. Gas emissions drifted S towards GrindavÃk. The Hazard Levels were raised to the highest and second highest levels (on a five-level scale) in five of the six zones, and an updated hazard map was released. Operations at the KeflavÃk International Airport were not disrupted, though according to a news report at least one flight path to the airport was modified. The eruption had peaked by 0210 on 21 November. The fissure was about 3 km long and no longer propagating; the S end of the fissure was located near Sýlingarfell. The lava effusion rate was an estimated 1,300 cubic meters per second, compared to approximately 2,500 cubic meters per second recorded during the August eruption. The lava front was about 500 m from GrindavÃkurvegur. Lava continued to advance W and curved slightly SW around the margins of previous lava flows and earthen barriers constructed to protect the Svartsengi power station and the Blue Lagoon. Workers continued to strengthen the barriers with additional material. Lava flowed over GrindavÃk road at about 0430 and just before 0800 the lava front reached the NjarðvÃk Line hot water pipeline; water flow was not disrupted. Lava crossed the Svartsengi power line at around 0900 which caused a power outage in GrindavÃk and disruptions across the Suðurnes region, based on a news source. IMO noted that by 1155 only the central part of the fissure was active, between Stóri-Skógfell and Sýlingarfell. By midday lava had reached the parking lot of the Blue Lagoon, about 4 km away from the fissure. The lava advanced over the asphalt faster than 100 meters per second during 1209-1335, and engulfed a service building. Subsidence was detected around Svartsengi. Both seismicity and deformation decreased significantly shortly after the eruption began; only a few minor earthquakes continued to be recorded and deformation was minimal in the vicinity of the fissure. An estimated 10 million cubic meters of lava was effused within the first few hours, about half of what had accumulated in the reservoir since the previous eruption. Overnight during 21-22 November activity along the fissure had concentrated into three segments, each with a growing cone. Lava from the middle crater flowed W and lava from the end craters flowed mostly E. The effusion rate had decreased significantly and lava advancement on the W part of the lava flow had notably slowed. Lava encountered higher areas of the ground, flowed N, and thickened. One of the hazard zones, Zone 4 which includes GrindavÃk, was lowered one step to the middle level. On 23 November the eruption continued at a steady rate from three craters and the middle cone remained the most active. No earthquakes were recorded, and subsidence continued to be detected. Lava continued to flow W and inflated along the earthen barriers at Svartsengi and Bláa Lónið. A channel of lava flowed along the S flanks of Stóra-Scógfell. By 0500 on 24 November activity at the craters subsided, though each continued to produce lava flows. Sulfur dioxide gas was detected in GrindavÃk during the previous few days. During the morning of 24 November tremor levels sharply declined and continued to slightly decrease during 24-25 November. The eruptive activity remained vigorous and was not decreasing as quickly as recorded during previous eruptions. The northern cone was the most active and lava from the cone flowed E. The southern cone ejected lava above the crater rim through the night but was not active on 25 November. Activity at the middle cone was not seen on 25 November. The surface of the W lava flow near Svartsengi had cooled. The eruption continued during 25-26 November, though both subsidence and eruptive activity decreased. Lava from the northern cone continued to flow E; no movement was detected at the W flow. The total volume of erupted lava was an estimated 43 million cubic meters and covered an area of about 8.5 square kilometers. 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!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk7R8V_J0Q$> ; Icelandic National Broadcasting Service (RUV) https://www.ruv.is/english/2024-11-20-eruption-on-reykjanes-peninsula-428068 <https://urldefense.com/v3/__https://www.ruv.is/english/2024-11-20-eruption-on-reykjanes-peninsula-428068__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk6GqdxhEA$> Sheveluch | Russia | 56.653°N, 161.36°E | Summit elev. 3283 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that lava extrusion may have continued at Sheveluchâ??s â??300 years of RASâ?? dome on the SW flank of Old Sheveluch and at the dome at Young Sheveluch during 14-21 November. Thermal anomalies over the domes were identified in satellite images during 16, 18, and 20-21 November. Weather conditions prevented views on the other days of the week. 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!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk7aOEAKlQ$> Ulawun | Papua New Guinea | 5.05°S, 151.33°E | Summit elev. 2334 m The Rabaul Volcano Observatory (RVO) reported that seismicity at Ulawun increased at around 1600 on 19 November and was characterized as an increase in the magnitude of events resembling volcano-tectonic signals. Signals indicating volcanic tremors increased at around 1830 on 20 November, increased again at around 2015, and then slightly decreased and continued at that level. RVO recommended a declaration of Alert Level Stage 1 (the lowest level of a four-stage scale). Geologic Summary. The symmetrical basaltic-to-andesitic Ulawun stratovolcano is the highest volcano of the Bismarck arc, and one of Papua New Guinea's most frequently active. The volcano, also known as the Father, rises above the N coast of the island of New Britain across a low saddle NE of Bamus volcano, the South Son. The upper 1,000 m is unvegetated. A prominent E-W escarpment on the south may be the result of large-scale slumping. Satellitic cones occupy the NW and E flanks. A steep-walled valley cuts the NW side, and a flank lava-flow complex lies to the south of this valley. Historical eruptions date back to the beginning of the 18th century. Twentieth-century eruptions were mildly explosive until 1967, but after 1970 several larger eruptions produced lava flows and basaltic pyroclastic flows, greatly modifying the summit crater. Source: Rabaul Volcano Observatory (RVO) https://webdev.datec.net.pg/geohazards/category/volcanoes/ <https://urldefense.com/v3/__https://webdev.datec.net.pg/geohazards/category/volcanoes/__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5R-MM2Mw$> Ongoing Activity Aira | Japan | 31.5772°N, 130.6589°E | Summit elev. 1117 m The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Calderaâ??s Sakurajima volcano) during 18-22 November. Nightly crater incandescence was visible in webcam images. An explosion at 2134 on 20 November generated an ash plume that rose 1.4 km above the crater rim and drifted SE. On 21 November sulfur dioxide emissions were very high, averaging 3,100 tons per day. An explosion at 0052 on 23 November generated an ash plume that rose 2.3 km above the crater rim and drifted S and ejected blocks 800-1,000 m from the vent. An ash plume from an eruptive event at 1458 on 23 November rose 1.6 km above the crater rim and drifted SE. 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!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk4WlDTBDw$> Banda Api | Indonesia | 4.523°S, 129.881°E | Summit elev. 596 m According to a news report the coordinator for the Banda Api observation post stated that the climbing route on the volcano was closed on 18 November due to increased seismicity. The coordinator noted that during 1 August-17 November there were 11 shallow volcanic earthquakes, 541 deep volcanic earthquakes, and 46 local and 250 distant tectonic earthquakes, respectively; three of the events were felt. The average number of earthquakes per day was between 13 and 30 events, though the average was as high as 40 per day. Though the volcano was sometimes obscured by weather conditions, diffuse white plumes were observed rising 20-30 m above the summit. The Alert Level remained at 2 (the second lowest level on a four-level scale) and the public was advised to stay 1 km away from the summit. Geologic Summary. The 3-km-wide island of Banda Api is the northern-most volcano in the Banda arc and has a long period of recorded observation because of its key location in the Portuguese and Dutch spice trade. The basaltic-to-rhyodacitic volcano is located in the SW corner of a mostly submerged 7 km caldera. At least two episodes of caldera formation are thought to have occurred, with the arcuate islands of Lonthor and Neira considered to be pre-caldera remnants. A conical peak rises to about 600 m at the center of the island. Eruptions have been recorded since 1586 CE, mostly consisting of Strombolian eruptions from the summit crater, but larger explosive eruptions have occurred and occasional lava flows have reached the coast. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5eVu8RGQ$> ; Antara News https://www.antaranews.com/berita/4485701/pos-pemantauan-gunung-api-banda-tutup-jalur-pendakian-sementara-waktu <https://urldefense.com/v3/__https://www.antaranews.com/berita/4485701/pos-pemantauan-gunung-api-banda-tutup-jalur-pendakian-sementara-waktu__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk7KvdUpVQ$> Dukono | Indonesia | 1.6992°N, 127.8783°E | Summit elev. 1273 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Dukono was ongoing during 20-26 November. Daily gray-and-white ash plumes that were sometimes dense generally rose as high as 3 km above the summit and drifted NW and W. According to a news report an ash plume that rose 1 km above the summit and drifted NW at 0606 on 25 November contained lightning and produced audible rumbling. PVMBG noted that ash plumes rose as high as 4.6 km above the summit and drifted NW on 26 November. The Alert Level remained at Level 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone. Geologic Summary. Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, have occurred since 1933. During a major eruption in 1550 CE, a lava flow filled in the strait between Halmahera and the N-flank Gunung Mamuya cone. This complex volcano presents a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also been active during historical time. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5eVu8RGQ$> ; Antara News https://megapolitan.antaranews.com/berita/322913/gunung-dukono-di-halmahera-utara-erupsi-keluarkan-abu-setinggi-4600-meter <https://urldefense.com/v3/__https://megapolitan.antaranews.com/berita/322913/gunung-dukono-di-halmahera-utara-erupsi-keluarkan-abu-setinggi-4600-meter__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk6lI-SdoQ$> Ebeko | Russia | 50.686°N, 156.014°E | Summit elev. 1103 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that moderate activity was ongoing at Ebeko during 14-21 November. A thermal anomaly over the volcano was identified in satellite images on 16 November; weather conditions prevented views on the other days. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are UTC; specific events are in local time where noted. Geologic Summary. The flat-topped summit of the central cone of Ebeko volcano, one of the most active in the Kuril Islands, occupies the northern end of Paramushir Island. Three summit craters located along a SSW-NNE line form Ebeko volcano proper, at the northern end of a complex of five volcanic cones. Blocky lava flows extend west from Ebeko and SE from the neighboring Nezametnyi cone. The eastern part of the southern crater contains strong solfataras and a large boiling spring. The central crater is filled by a lake about 20 m deep whose shores are lined with steaming solfataras; the northern crater lies across a narrow, low barrier from the central crater and contains a small, cold crescentic lake. Historical activity, recorded since the late-18th century, has been restricted to small-to-moderate explosive eruptions from the summit craters. Intense fumarolic activity occurs in the summit craters, on the outer flanks of the cone, and in lateral explosion craters. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk7aOEAKlQ$> Great Sitkin | United States | 52.076°N, 176.13°W | Summit elev. 1740 m The Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick lava flow in Great Sitkinâ??s summit crater during 18-26 November. The flow had filled most of the summit crater with minor advancement in the N part of the E lobe. The local seismic network continued to detect small earthquakes associated with the ongoing eruption. Weather clouds obscured webcam and satellite views of the summit most of the week, though elevated surface temperatures were identified in satellite images during 18-19 and 23-24 November. 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!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk7FAGAbpQ$> Ibu | Indonesia | 1.488°N, 127.63°E | Summit elev. 1325 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 20-26 November. Daily gray or white-and-gray ash plumes that were often dense rose as high as 1.2 km above the summit and drifted mainly SW, W, and NW. Daily webcam images posted with the reports showed incandescence at the summit of the inner active cone. The Alert Level remained at 3 (the second highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 5 km away from the N crater wall opening. Geologic Summary. The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, has contained several small crater lakes. The 1.2-km-wide outer crater is breached on the N, creating a steep-walled valley. A large cone grew ENE of the summit, and a smaller one to the WSW has fed a lava flow down the W flank. A group of maars is located below the N and W flanks. The first observed and recorded eruption was a small explosion from the summit crater in 1911. Eruptive activity began again in December 1998, producing a lava dome that eventually covered much of the floor of the inner summit crater along with ongoing explosive ash emissions. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5eVu8RGQ$> Kanlaon | Philippines | 10.4096°N, 123.13°E | Summit elev. 2422 m The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported a continuing eruption at Kanlaon during 19-25 November. The seismic network recorded 3-23 daily volcanic earthquakes, and sulfur dioxide emissions ranged from 5,125 to 8,040 tonnes per day; weather clouds obscured views on 19 November. Moderate gas-and-steam emissions high as 300 m above the summit and drifted SW and WSW. There was one ash emission event on 21 November and two on 23 November, with each lasting 4-8 minutes long. According to the Tokyo VAAC the ash emissions rose as high as 2.7 km (9,000 ft) a.s.l. and drifted W and SW. 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!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk4l8xIAbA$> ; Tokyo Volcanic Ash Advisory Center (VAAC) http://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html <https://urldefense.com/v3/__http://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk7dLQAKcA$> Karymsky | Russia | 54.049°N, 159.443°E | Summit elev. 1513 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported moderate levels of activity at Karymsky during 14-21 November. A thermal anomaly over the volcano was identified in satellite images during 16 and 19-20 November; weather conditions prevented views on the other days. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk7aOEAKlQ$> Kuchinoerabujima | Japan | 30.443°N, 130.217°E | Summit elev. 657 m The Japan Meteorological Agency (JMA) reported that volcanic activity at Kuchinoerabujima had been declining since mid-August. The number of shallow volcanic earthquakes that had been frequent since the beginning of April, with most epicenters located near Furudake Crater, and few near Shindake Crater (just N of Furudake), had declined; no large-amplitude earthquakes had been recorded. There were no notable changes to hydrothermal fields from late October to mid-November. Sulfur dioxide gas emissions were at low levels, fluctuating between 20 and 60 tons per day, and occasionally below detectable limits. The Alert Level was lowered to 1 (on a scale of 1-5) at 1100 on 20 November and the public was warned to exercise caution around the craters and not to enter restricted areas. Geologic Summary. A group of young stratovolcanoes forms the eastern end of the irregularly shaped island of Kuchinoerabujima in the northern Ryukyu Islands, 15 km W of Yakushima. The Furudake, Shindake, and Noikeyama cones were erupted from south to north, respectively, forming a composite cone with multiple craters. All historical eruptions have occurred from Shindake, although a lava flow from the S flank of Furudake that reached the coast has a very fresh morphology. Frequent explosive eruptions have taken place from Shindake since 1840; the largest of these was in December 1933. Several villages on the 4 x 12 km island are located within a few kilometers of the active crater and have suffered damage from eruptions. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk4WlDTBDw$> Manam | Papua New Guinea | 4.08°S, 145.037°E | Summit elev. 1807 m The Darwin Volcanic Ash Advisory Centre (VAAC) reported that continuous ash emissions Manam were identified in satellite images during 20-25 November rising to 2.4 km (8,000 ft) a.s.l. and drifting NW, W, and SW. Weather clouds occasionally obscured or partially obscured views. Geologic Summary. The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical basaltic-andesitic stratovolcano to its lower flanks. These valleys channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Five small satellitic centers are located near the island's shoreline on the northern, southern, and western sides. Two summit craters are present; both are active, although most observed eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE valley. Frequent eruptions, typically of mild-to-moderate scale, have been recorded since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas. Source: Darwin Volcanic Ash Advisory Centre (VAAC) http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml <https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk4h8VNXAg$> Merapi | Indonesia | 7.54°S, 110.446°E | Summit elev. 2910 m The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 15-21 November. Seismicity was higher compared to the previous week. The SW lava dome produced 196 lava avalanches that traveled as far as 2 km down the Bebeng drainage on the SW flank. Morphological changes to the SW lava dome resulted from continuing effusion and collapses of material. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location. Geologic Summary. Merapi, one of Indonesia's most active volcanoes, lies in one of the world's most densely populated areas and dominates the landscape immediately north of the major city of Yogyakarta. It is the youngest and southernmost of a volcanic chain extending NNW to Ungaran volcano. Growth of Old Merapi during the Pleistocene ended with major edifice collapse perhaps about 2,000 years ago, leaving a large arcuate scarp cutting the eroded older Batulawang volcano. Subsequent growth of the steep-sided Young Merapi edifice, its upper part unvegetated due to frequent activity, began SW of the earlier collapse scarp. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated lands on the western-to-southern flanks and caused many fatalities. Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) http://www.merapi.bgl.esdm.go.id/ <https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5br35ctA$> Nevado del Ruiz | Colombia | 4.892°N, 75.324°W | Summit elev. 5279 m Servicio Geológico Colombianoâ??s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that eruptive activity at Nevado del Ruiz continued during 19-25 November. The number of seismic events associated with fluid movement decreased in number but increased in magnitude compared to the previous week. Additionally, the number of low-level, long-duration events increased. Webcam images confirmed several ash emissions and higher-temperature ejecta associated with some of these events, though weather clouds sometimes obscured views. Seismicity associated with rock fracturing remained similar in number but decreased in magnitude compared to the previous week. The earthquakes were less than M 1, located below Arenas Crater and the SSW, NE, and SE flanks within 10 km, and had depths of 1-7 km. Low-energy thermal anomalies on the crater floor were identified in satellite data when weather permitted. Gas plumes rose up to 1.3 km above the crater rim and drifted SW on 21 and 24 November. Sulfur dioxide emissions detected in satellite data were similar to previous weeks. The Alert Level remained at Yellow (the second level on a four-level scale), and the public was warned to stay out of the restricted areas around Arenas Crater, not to spend long periods of time on the Murillo-Cerro Gualà Road, and to avoid drainages in the high-threat zones. Geologic Summary. Nevado del Ruiz is a broad, glacier-covered volcano in central Colombia that covers more than 200 km2. Three major edifices, composed of andesitic and dacitic lavas and andesitic pyroclastics, have been constructed since the beginning of the Pleistocene. The modern cone consists of a broad cluster of lava domes built within the caldera of an older edifice. The 1-km-wide, 240-m-deep Arenas crater occupies the summit. The prominent La Olleta pyroclastic cone located on the SW flank may also have been active in historical time. Steep headwalls of massive landslides cut the flanks. Melting of its summit icecap during historical eruptions, which date back to the 16th century, has resulted in devastating lahars, including one in 1985 that was South America's deadliest eruption. Source: Servicio Geológico Colombiano (SGC) https://www2.sgc.gov.co/volcanes/index.html <https://urldefense.com/v3/__https://www2.sgc.gov.co/volcanes/index.html__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk6-x-edcg$> Semeru | Indonesia | 8.108°S, 112.922°E | Summit elev. 3657 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity continued at Semeru during 20-26 November with several daily eruptive events recorded by the seismic network. White-and-gray ash plumes that were sometimes dense rose 400-900 m above the summit and drifted N, W, and SW. Weather conditions sometimes prevented views of the summit on 24 and 26 November. The Alert Level remained at 2 (the second lowest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards. Geologic Summary. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk5eVu8RGQ$> Suwanosejima | Japan | 29.638°N, 129.714°E | Summit elev. 796 m The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 18-25 November. An explosion at 1908 on 18 November generated an ash plume that rose 1 km above the crater rim and drifted S. Multiple eruptive events recorded during 18-19 and 23-24 November produced ash plumes that rose 0.8-1.4 km above the crater rim and drifted mainly SW and W. 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!fA_3efZ3Bgbm9zpJJzZwNknSl9mW3fP4tiGmaE7dRdPuatg-qchtpK4ecX4B3tJpxpEyXCO8fLQIj6wAEk4WlDTBDw$> 11-11-11-11-11-11-11-11-11-11-11-11 ============================================================== 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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