6-6-6-6-6-6-6-6-6-6-6-6-6 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 11-17 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!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeDxssATPw$> New Activity/Unrest: Bagana, Papua New Guinea | Kanlaon, Philippines | Kilauea, United States | Whakaari/White Island, New Zealand Ongoing Activity: Aira, Japan | Dukono, Indonesia | Ebeko, Russia | Great Sitkin, United States | Ibu, Indonesia | Karymsky, Russia | Lewotobi, Indonesia | Manam, Papua New Guinea | Marapi, Indonesia | Merapi, Indonesia | Nyamulagira, DR Congo | Popocatepetl, Mexico | Sabancaya, Peru | Semeru, Indonesia | Sheveluch, Russia | Suwanosejima, Japan The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday, these reports are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of all of Earth's volcanoes erupting during the week, but rather a summary of activity at volcanoes that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed reports about recent activity are published in issues of the Bulletin of the Global Volcanism Network. Note that many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source. New Activity/Unrest Bagana | Papua New Guinea | 6.137°S, 155.196°E | Summit elev. 1855 m The Darwin VAAC reported that continuous ash plumes from Bagana were identified in satellite images rising to 2.4-3.7 km (8,000-12,000 ft) a.s.l. and drifting S and SW at 2310 on 16 September and 0150 and 0410 on 17 September. Geologic Summary. Bagana volcano, in a remote portion of central Bougainville Island, is frequently active. This massive symmetrical cone was largely constructed by an accumulation of viscous andesitic lava flows. The entire edifice could have been constructed in about 300 years at its present rate of lava production. Eruptive activity is characterized by non-explosive effusion of viscous lava that maintains a small lava dome in the summit crater, although occasional explosive activity produces pyroclastic flows. Lava flows with tongue-shaped lobes up to 50 m thick and prominent levees descend the flanks on all sides. 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!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeDyTdRlhA$> Kanlaon | Philippines | 10.4096°N, 123.13°E | Summit elev. 2422 m PHIVOLCS reported continuing unrest at Kanlaon during 11-17 September, characterized by increased seismicity and sulfur dioxide emissions. Sulfur dioxide emissions reached a record high on 11 September, averaging 11,556 tonnes/day (t/d), before decreasing slightly to 10,880 t/d on 12 September; emissions were not reported the rest of the week. The number of volcanic earthquakes detected by the seismic network was 337 during 10-11 September and 79 recorded during 11-12 September. The daily number fluctuated from 2 to 32 on the other days. Weather clouds obscured views of the summit during the second half of the week. 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. According to a Disaster Response Operations Monitoring and Information Center (DROMIC) report there were a total of 2,298 people in evacuation centers as of 16 September. 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!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeBlxzKFUQ$> ; Disaster Response Operations Monitoring and Information Center (DROMIC) https://dromic.dswd.gov.ph/ <https://urldefense.com/v3/__https://dromic.dswd.gov.ph/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeC9RSg87w$> Kilauea | United States | 19.421°N, 155.287°W | Summit elev. 1222 m HVO reported that deformation analysis of an interferogram based on satellite images acquired over Kilauea during 2-14 September indicated that a dike intruded between Pauahi and Makaopuhi craters along the middle East Rift Zone. Seismicity and deformation increased dramatically at around 1600 on 14 September with most of the earthquakes located at depths of 1-3 km below the surface. The largest earthquake was an M 4.3 recorded at 1625 on 14 September and located in the S part of Kaluapele; this earthquake was associated with slip along one of the outer caldera faults and a consequence of stress changes due to the dike intrusion. Activity levels decreased overnight during 14-15 September; seismicity continued at less intense levels on 15 September, though deformation data continued to show moving magma. During 2100-2200 on 15 September, infrasound instruments detected strong signals typical of gas or steam venting, and seismometers in the middle East Rift Zone recorded weak, sustained, low-frequency tremor. Residents in nearby subdivisions downwind reported smelling volcanic gas around that same time. There was no evidence of eruptive activity in webcam images and GOES satellite data did not show thermal anomalies, though heavy rainfall in the area complicated the interpretation. HVO issued a Volcanic Activity Notice (VAN) at 0023 on 16 September raising the Volcano Alert Level to Watch (the third level on a four-level scale) and the Aviation Color Code to Orange (the third color on a four-color scale) and noting that monitoring data indicated a continuing intrusion. Hawaiâ??i Volcanoes National Park closed the Chain of Craters Road and other nearby areas in response to the increased activity. During an overflight around 1000 on 16 September HVO scientists confirmed that an eruption had occurred during the night in an area just W of Napau Crater, near the Napau campsite in a remote area of the National Park. Two lava flows had erupted from a 480-m-long fissure with two segments, covering an area of approximately 16,500 square meters; the larger flow was about 200 m long. No active lava flows were seen during the overflight, but gas-and-steam was rising from the fissure. The campground was not affected but lava possibly covered a pulu (Hawaiian tree fern) station nearby, and vegetation along the margins of the flow field was burned. Chain of Craters Road is downslope and downwind of the new fissures. The eruption resumed at about 1800 on 16 September with the activity visible in webcam images. During an overflight during the morning of 17 September volcanologists observed activity at fissures that had opened on the Napau Crater floor, downrift (NE) of the previous fissures that had opened on 15 September and were no longer active. The fissure on the crater floor was about 500 m long and trended E-W along the N part of the crater floor. Lava fountains rose 10 m from areas along the fissure, and by 0830 about 25-30 percent of the crater floor had been covered by lava. HVO released a map showing the margins the flow field as of 1030 on the 17th, based on observations made during the last helicopter overflight. The map showed that lava from the first set of fissures had flowed NE down into the Napau Crater during 16-17 September. The total length of the fissure system was more than 1.6 km and lava flow covered about 18 hectares (180,000 square meters). 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. Sources: US Geological Survey Hawaiian Volcano Observatory (HVO) https://volcanoes.usgs.gov/observatories/hvo/ <https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeAgQzt6iw$> ; US Hawaii Volcanoes National Park http://www.nps.gov/havo/ <https://urldefense.com/v3/__http://www.nps.gov/havo/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeDyl0IQ5w$> Whakaari/White Island | New Zealand | 37.52°S, 177.18°E | Summit elev. 294 m GeoNet reported that a low-level eruption at Whakaari/White Island was ongoing through 12 September, confirmed by data from webcams, overflights, and satellite images. Sulfur dioxide emissions recorded during a 5 September overflight were some of the highest during the previous 20 years. The rate of emissions was lower during an 11 September overflight; though emissions were variable the total gas output remained at higher than normal levels. The vent area appeared slightly larger on 11 September. The plumes were darker and higher based on webcam images on 11 September, suggesting a substantially higher ash content; less ash was present in the plumes on 12 September. According to the Wellington VAAC ash-and-gas plumes rose 0.9 km (3,000 ft) a.s.l. and drifted E and SE during 13-14 September. The gas-and-ash plumes had been rising a few hundred meters to 1 km above the volcano and drifting tens of kilometers downwind. The plumes were sometimes tracked as far as 100 km downwind, and occasionally the plumes had passed over land. Ash fell as far as 3 km from the island. The Volcanic Alert Level remained at 3 (on a scale of 0-5) and the Aviation Color Code remained at Orange (the second highest level on a four-color scale). 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. Sources: GeoNet http://www.geonet.org.nz/ <https://urldefense.com/v3/__http://www.geonet.org.nz/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeCXehWEng$> ; Wellington Volcanic Ash Advisory Center (VAAC) http://vaac.metservice.com/ <https://urldefense.com/v3/__http://vaac.metservice.com/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeBc3CKHgg$> Ongoing Activity Aira | 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 9-16 September. Crater incandescence was visible in webcam images during dark hours, and there were occasional very small eruptive events. An explosion at 1332 on 16 September generated an ash plume that rose 1.5 km above the crater rim and drifted NW. 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!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeBf1e-9eQ$> Dukono | Indonesia | 1.6992°N, 127.8783°E | Summit elev. 1273 m PVMBG reported that the eruption at Dukono was ongoing during 11-17 September. Gray-and-white ash plumes that were sometimes dense rose 100-600 m above the summit and drifted E on 11 and 17 September. Emissions were not observed on the other days. The Alert Level remained at Level 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone. Geologic Summary. Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, have occurred since 1933. During a major eruption in 1550 CE, a lava flow filled in the strait between Halmahera and the N-flank Gunung Mamuya cone. This complex volcano presents a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also been active during historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeBQFvu17Q$> Ebeko | Russia | 50.686°N, 156.014°E | Summit elev. 1103 m KVERT reported that moderate explosive activity was ongoing at Ebeko during 6-12 September. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E), explosions during 5-9 and 11-12 September generated ash plumes that rose as high as 3 km (10,000 ft) a.s.l. and drifted N, NE, and E. 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!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeDvSPu07w$> Great Sitkin | United States | 52.076°N, 176.13°W | Summit elev. 1740 m AVO reported that slow lava effusion continued to feed a thick lava flow in Great Sitkinâ??s summit crater during 10-17 September. Seismicity was low with few small daily earthquakes and rockfalls associated with the advancing E lobe. Elevated surface temperatures over the active flow were identified in satellite data on 11 September. Weather clouds often obscured views of the summit. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale). Geologic Summary. The Great Sitkin volcano forms much of the northern side of Great Sitkin Island. A younger volcano capped by a small, 0.8 x 1.2 km ice-filled summit caldera was constructed within a large late-Pleistocene or early Holocene scarp formed by massive edifice failure that truncated an older edifice and produced a submarine debris avalanche. Deposits from this and an even older debris avalanche from a source to the south cover a broad area of the ocean floor north of the volcano. The summit lies along the eastern rim of the younger collapse scarp. Deposits from an earlier caldera-forming eruption of unknown age cover the flanks of the island to a depth up to 6 m. The small younger caldera was partially filled by lava domes emplaced in 1945 and 1974, and five small older flank lava domes, two of which lie on the coastline, were constructed along northwest- and NNW-trending lines. Hot springs, mud pots, and fumaroles occur near the head of Big Fox Creek, south of the volcano. Eruptions have been recorded since the late-19th century. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://avo.alaska.edu/ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeCa84njKQ$> Ibu | Indonesia | 1.488°N, 127.63°E | Summit elev. 1325 m PVMBG reported that activity at Ibu continued during 11-17 September with multiple eruptive events recorded daily. On most days gray or white-and-gray ash plumes that were sometimes dense rose as high as 1.5 km above the summit and drifted in multiple directions. Two eruptive events were recorded on 14 September, though no emissions were visible. 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!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeBQFvu17Q$> Karymsky | Russia | 54.049°N, 159.443°E | Summit elev. 1513 m KVERT reported moderate levels of activity at Karymsky during 6-12 September. Explosions during the week produced ash plumes that rose as high as 3 km (10,000 ft) a.s.l. and drifted 500 km NE. A thermal anomaly over the volcano was identified in satellite images during 7-8 September. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeDvSPu07w$> Lewotobi | Indonesia | 8.542°S, 122.775°E | Summit elev. 1703 m PVMBG reported that eruptive activity at Lewotobiâ??s Laki-laki volcano continued during 11-17 September 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 km above the summit and drifted SW, W, and NW. 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. 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!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeBQFvu17Q$> Manam | Papua New Guinea | 4.08°S, 145.037°E | Summit elev. 1807 m The Darwin VAAC reported that at 2040 on 11 September an ash plume from Manam was identified in a satellite image rising 5.2 km (17,000 ft) a.s.l. and drifting NNW. The plume had dissipated by 0210 on 12 September. Geologic Summary. The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical basaltic-andesitic stratovolcano to its lower flanks. These valleys channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Five small satellitic centers are located near the island's shoreline on the northern, southern, and western sides. Two summit craters are present; both are active, although most observed eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE valley. Frequent eruptions, typically of mild-to-moderate scale, have been recorded since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas. Source: Darwin Volcanic Ash Advisory Centre (VAAC) http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml <https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeDyTdRlhA$> Marapi | Indonesia | 0.38°S, 100.474°E | Summit elev. 2885 m PVMBG reported that eruptive activity at Marapi (on Sumatra) was ongoing during 11-17 September. On 11 and 13 September white emissions rose 100-150 m above the summit and drifted E. White-and-gray ash plumes rose 100-300 m above the summit and drifted E and NE. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay 3 km away from the active crater. Geologic Summary. Gunung Marapi, not to be confused with the better-known Merapi volcano on Java, is Sumatra's most active volcano. This massive complex stratovolcano rises 2,000 m above the Bukittinggi Plain in the Padang Highlands. A broad summit contains multiple partially overlapping summit craters constructed within the small 1.4-km-wide Bancah caldera. The summit craters are located along an ENE-WSW line, with volcanism migrating to the west. More than 50 eruptions, typically consisting of small-to-moderate explosive activity, have been recorded since the end of the 18th century; no lava flows outside the summit craters have been reported in historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeBQFvu17Q$> Merapi | Indonesia | 7.54°S, 110.446°E | Summit elev. 2910 m BPPTKG reported that the eruption at Merapi (on Java) continued during 6-12 September. Seismicity was slightly more intense compared to the previous week. The SW lava dome produced 167 lava avalanches that traveled as far as 1.8 km down the Bebeng drainage on the SW flank. Three pyroclastic flows descended the Bebeng as far as 1.5 km. Morphological changes to the SW lava dome were due to continuing effusion and collapses of material. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location. Geologic Summary. Merapi, one of Indonesia's most active volcanoes, lies in one of the world's most densely populated areas and dominates the landscape immediately north of the major city of Yogyakarta. It is the youngest and southernmost of a volcanic chain extending NNW to Ungaran volcano. Growth of Old Merapi during the Pleistocene ended with major edifice collapse perhaps about 2,000 years ago, leaving a large arcuate scarp cutting the eroded older Batulawang volcano. Subsequent growth of the steep-sided Young Merapi edifice, its upper part unvegetated due to frequent activity, began SW of the earlier collapse scarp. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated lands on the western-to-southern flanks and caused many fatalities. Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) http://www.merapi.bgl.esdm.go.id/ <https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeAue9NKWw$> Nyamulagira | DR Congo | 1.408°S, 29.2°E | Summit elev. 3058 m Satellite images from 13 and 18 September indicated continuing activity at Nyamuragira. The end of the NNW lava flow was about 7.6 km from the crater rim based on a 13 September satellite image and had advanced a short distance by 18 September. Lava had branched from the flow in an area about 1.3 km upslope from the end of the flow and traveled about 1.6 km NE. Lava flows that had breached the NNW crater rim traveled W and SW. The farthest end of the W flow was about 5 km from the crater rim and the end of the SW flow was about 3 km from the crater rim. Small thermal anomalies were visible near the ends of the NNW flow and in areas along the W and WSW flows. A larger thermal anomaly was present the part of the eastern crater floor. An 18 September image showed that the thermal anomaly in the main crater had shifted to the NW part of the crater. Scattered thermal anomalies on the flow fields indicated breakouts in areas along the margins of the NNW, W, and SW. Weather clouds slightly obscured the crater and flow field in the 13 September image but obscured most of the flow field and part of the crater in the 18 September image. Geologic Summary. Africa's most active volcano, Nyamulagira (also known as Nyamuragira), is a massive high-potassium basaltic shield about 25 km N of Lake Kivu and 13 km NNW of the steep-sided Nyiragongo volcano. The summit is truncated by a small 2 x 2.3 km caldera that has walls up to about 100 m high. Documented eruptions have occurred within the summit caldera, as well as from the numerous flank fissures and cinder cones. A lava lake in the summit crater, active since at least 1921, drained in 1938, at the time of a major flank eruption. Recent lava flows extend down the flanks more than 30 km from the summit as far as Lake Kivu; extensive lava flows from this volcano have covered 1,500 km2 of the western branch of the East African Rift. Source: Copernicus https://www.copernicus.eu/en <https://urldefense.com/v3/__https://www.copernicus.eu/en__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeDdFEB-Cg$> Popocatepetl | Mexico | 19.023°N, 98.622°W | Summit elev. 5393 m CENAPRED reported that eruptive activity continued at Popocatépetl during 10-17 September. The seismic network recorded 18-65 long-period events per day that were accompanied by steam-and-gas emissions which sometimes contained minor amounts of ash. The seismic network also recorded daily tremor with periods lasting from 46 minutes up to six hours and 37 minutes. Two volcano-tectonic earthquakes were recorded during 12-14 September. The Alert Level remained at Yellow, Phase Two (the middle level on a three-color scale) and the public was warned to stay 12 km away from the crater. Geologic Summary. Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, rises 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 400 x 600 m wide crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano. At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas to the south. The modern volcano was constructed south of the late-Pleistocene to Holocene El Fraile cone. Three major Plinian eruptions, the most recent of which took place about 800 CE, have occurred since the mid-Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since Pre-Columbian time. Source: Centro Nacional de Prevencion de Desastres (CENAPRED) https://www.gob.mx/cenapred <https://urldefense.com/v3/__https://www.gob.mx/cenapred__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeCnt5sxkQ$> Sabancaya | Peru | 15.787°S, 71.857°W | Summit elev. 5960 m Instituto GeofÃsico del Perú (IGP) reported that the eruption at Sabancaya continued during 9-15 September with a daily average of 34 explosions. Gas-and-ash plumes rose as high as 2 km above the summit and drifted less than 10 km SE and S. Thermal anomalies over the lava dome in the summit crater were identified in satellite data. Slight inflation was detected N of Hualca Hualca (7 km N). Sulfur dioxide emissions were at moderate levels, averaging 580 tons per day. The Alert Level remained at Orange (the third level on a four-color scale) and the public was warned to stay outside of a 12 km radius. Geologic Summary. Sabancaya, located in the saddle NE of Ampato and SE of Hualca Hualca volcanoes, is the youngest of these volcanic centers and the only one to have erupted in historical time. The oldest of the three, Nevado Hualca Hualca, is of probable late-Pliocene to early Pleistocene age. The name Sabancaya (meaning "tongue of fire" in the Quechua language) first appeared in records in 1595 CE, suggesting activity prior to that date. Holocene activity has consisted of Plinian eruptions followed by emission of voluminous andesitic and dacitic lava flows, which form an extensive apron around the volcano on all sides but the south. Records of observed eruptions date back to 1750 CE. Source: Instituto GeofÃsico del Perú (IGP) http://www.igp.gob.pe/ <https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeAkMZL_2A$> Semeru | Indonesia | 8.108°S, 112.922°E | Summit elev. 3657 m PVMBG reported that eruptive activity continued at Semeru during 11-18 September with multiple daily eruptive events recorded by the seismic network. White-and-gray ash plumes that were sometimes dense rose 150-700 m above the summit and drifted in multiple directions. The Alert Level remained at 2 (the second lowest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards. Geologic Summary. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeBQFvu17Q$> Sheveluch | Russia | 56.653°N, 161.36°E | Summit elev. 3283 m KVERT reported that during 6-12 September lava extrusion likely continued at Sheveluchâ??s â??300 years of RASâ?? dome on the SW flank of Old Sheveluch and at Young Sheveluch. Thermal anomalies over the domes were identified in satellite images on 7 and 10 September; weather clouds obscured the volcano on the other days. 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!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeDvSPu07w$> Suwanosejima | Japan | 29.638°N, 129.714°E | Summit elev. 796 m JMA reported that eruptive activity at Suwanosejima's Ontake Crater continued during 9-16 September and crater incandescence was observed nightly in webcam images. Explosions were recorded at 1728 on 9 September, at 1001 on 11 September, at 1345 on 12 September, and at 1948 on 13 September. Volcanic plumes generated by the explosions rose as high as 800 m above the crater rim. The Alert Level remained at 2 (on a 5-level scale) and the public was warned to stay at least 1.5 km away from the crater. Geologic Summary. The 8-km-long island of Suwanosejima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two active summit craters. The summit is truncated by a large breached crater extending to the sea on the E flank that was formed by edifice collapse. One of Japan's most frequently active volcanoes, it was in a state of intermittent Strombolian activity from Otake, the NE summit crater, between 1949 and 1996, after which periods of inactivity lengthened. The largest recorded eruption took place in 1813-14, when thick scoria deposits covered residential areas, and the SW crater produced two lava flows that reached the western coast. At the end of the eruption the summit of Otake collapsed, forming a large debris avalanche and creating an open collapse scarp extending to the eastern coast. The island remained uninhabited for about 70 years after the 1813-1814 eruption. Lava flows reached the eastern coast of the island in 1884. Only about 50 people live on the island. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!e-8irUBLaxBTFg-i-fwktr1JTc7lkT5wonIhM8QRSbMfZrsvJBuYNFjJIUJe2W41RY4GC8-wJaVKp-FwoeBf1e-9eQ$> 6-6-6-6-6-6-6-6-6-6-6-6-6 ============================================================== 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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