6-6-6-6-6-6-6-6-6-6-6-6-6 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 25 September-1 October 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtgCv3jXlg$> New Activity/Unrest: Kanlaon, Philippines | Taal, Philippines | Whakaari/White Island, New Zealand Ongoing Activity: Aira, Japan | Ambae, Vanuatu | Bezymianny, Russia | Dukono, Indonesia | Ebeko, Russia | Etna, Italy | Great Sitkin, United States | Ibu, Indonesia | Karymsky, Russia | Lewotobi, Indonesia | Manam, Papua New Guinea | Merapi, Indonesia | Nevado del Ruiz, Colombia | Nyamulagira, DR Congo | Popocatepetl, Mexico | Reventador, Ecuador | Rincon de la Vieja, Costa Rica | Sabancaya, Peru | Semeru, Indonesia | Sheveluch, Russia | Stromboli, Italy | Suwanosejima, Japan | Yasur, Vanuatu The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday, these reports are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of all of Earth's volcanoes erupting during the week, but rather a summary of activity at volcanoes that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed reports about recent activity are published in issues of the Bulletin of the Global Volcanism Network. Note that many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source. New Activity/Unrest Kanlaon | Philippines | 10.4096°N, 123.13°E | Summit elev. 2422 m Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing unrest at Kanlaon during 25 September-1 October, characterized by increased seismicity and sulfur dioxide emissions. The seismic network recorded 7-16 daily volcanic earthquakes. Daily gas-and-steam emissions that were voluminous mid-week rose 100-850 m above the summit and drifted in multiple directions. Sulfur dioxide emissions were recorded daily and continued to be high, averaging 4,992-8,973 tonnes/day. 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. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS) http://www.phivolcs.dost.gov.ph/ <https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtjkIScmug$> Taal | Philippines | 14.0106°N, 120.9975°E | Summit elev. 311 m Philippine Institute of Volcanology and Seismology (PHIVOLCS) issued advisories for Taal reporting that a total of 18 phreatic events were recorded almost daily during 22 September-2 October. There were 1-3 daily phreatic events during 22-23 and 25-30 September, each lasting 1-8 minutes long based on visual, seismic, and infrasound data. Five of the events occurred during 0110-0437 on 1 October. Daily white steam-and-gas emissions that were sometime voluminous rose 0.7-2.1 km above the crater rim and drifted in multiple directions. Hot fluids were visible upwelling in the lake almost daily. A phreatomagmatic eruption recorded during 1621-1632 on 2 October ejected short black jets of material followed by a voluminous steam-rich plume that rose 2.4 km and drifted NE. PHIVOLCS concluded that the event was likely driven by water contacting a small body of shallow magma that has been steadily degassing for the previous three years; deformation and seismic data were at background levels and did not indicated that the unrest would escalate into a large magmatic eruption. Sulfur dioxide emissions were measured a few times during 22 September-2 October and trended downward, averaging 8,927 tonnes per day (t/d) on 21 September, 4,899 t/d on 23 September, 1,510 t/d on 28 September, 1,354 t/d on 30 September, and 2,532 t/d on 2 October. PHIVOLCS noted that sulfur dioxide emissions had been high in 2024, averaging 6,712 t/d since January. The Alert Level remained at 1 (on a scale of 0-5), and PHIVOLCS reminded the public that the entire Taal Volcano Island was a Permanent Danger Zone (PDZ) and recommended that the Main Crater and areas along the Daang Kastila fissure should remain prohibited. Geologic Summary. Taal is one of the most active volcanoes in the Philippines and has produced some powerful eruptions. The 15 x 20 km Talisay (Taal) caldera is largely filled by Lake Taal, whose 267 km2 surface lies only 3 m above sea level. The maximum depth of the lake is 160 m, with several submerged eruptive centers. The 5-km-wide Volcano Island in north-central Lake Taal is the location of all observed eruptions. The island is composed of coalescing small stratovolcanoes, tuff rings, and scoria cones. Powerful pyroclastic flows and surges have caused many fatalities. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS) http://www.phivolcs.dost.gov.ph/ <https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtjkIScmug$> Whakaari/White Island | New Zealand | 37.52°S, 177.18°E | Summit elev. 294 m On 30 September GeoNet reported that minor ash emissions at Whakaari/White Island continued during the previous week, but possibly at lower levels based on aerial observations, views on webcams located in Whakatane and Te Kaha, and satellite observations. During a 24 September overflight, scientists observed that the emissions contained less ash and the plumes were both less vigorous and not as continuous. Ash-and-gas plumes rose as high as 1 km above the island. Any ashfall was confined to the island and the likelihood of ashfall on the mainland remained low. 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. Source: GeoNet http://www.geonet.org.nz/ <https://urldefense.com/v3/__http://www.geonet.org.nz/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtivUkw9YA$> Ongoing Activity Aira | Japan | 31.5772°N, 130.6589°E | Summit elev. 1117 m Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Calderaâ??s Sakurajima volcano) during 23-30 September. Crater incandescence was visible in webcam images during dark hours. During a field survey on 26 September scientists observed no new changes to the geothermal area on the SE flank of Minamidake nor near Showa Crater compared to previous observations. Incandescence at Minamidake was barely visible with the naked eye. An eruptive event at 2001 on 26 September generated an ash plume that rose 1.3 km above the crater rim and drifted SW. Very small eruptive events were occasionally recorded during 27-30 September. 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtiHAZVp2A$> Ambae | Vanuatu | 15.389°S, 167.835°E | Summit elev. 1496 m On 26 September the Vanuatu Meteorology and Geohazards Department (VMGD) reported that steam-and-gas emissions from the active vents at Ambae were ongoing during the previous month; ash content was not confirmed. The observations were based on webcam and satellite images and field observations. Seismic data also confirmed ongoing unrest. The Alert Level remained at 2 (on a scale of 0-5), and the public was warned to stay outside of the Danger Zone, defined as a 2-km radius around the active vents in Lake Voui, and away from drainages during heavy rains. Geologic Summary. The island of Ambae, also known as Aoba, is a massive 2,500 km3 basaltic shield that is the most voluminous volcano of the New Hebrides archipelago. A pronounced NE-SW-trending rift zone with numerous scoria cones gives the 16 x 38 km island an elongated form. A broad pyroclastic cone containing three crater lakes (Manaro Ngoru, Voui, and Manaro Lakua) is located at the summit within the youngest of at least two nested calderas, the largest of which is 6 km in diameter. That large central edifice is also called Manaro Voui or Lombenben volcano. Post-caldera explosive eruptions formed the summit craters about 360 years ago. A tuff cone was constructed within Lake Voui (or Vui) about 60 years later. The latest known flank eruption, about 300 years ago, destroyed the population of the Nduindui area near the western coast. Source: Vanuatu Meteorology and Geohazards Department (VMGD) http://www.geohazards.gov.vu/ <https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qthWjHJwfQ$> Bezymianny | Russia | 55.972°N, 160.595°E | Summit elev. 2882 m The Kamchatka Volcanic Eruption Response Team (KVERT) reported that a thermal anomaly over Bezymianny was identified in satellite images during 20-21 and 23-26 September. The volcano was obscured by weather clouds on the other days of the week. On 25 September a plume of resuspended ash lifted from the S flank by strong winds was visible in satellite and webcam images drifting 90 km E. The resuspended ash prompted KVERT to briefly raise the Aviation Color Code from Yellow to Orange (the second highest level on a four-color scale) at 2310; the Aviation Color Code was lowered back to Yellow at 0323 on 26 September. Geologic Summary. The modern Bezymianny, much smaller than its massive neighbors Kamen and Kliuchevskoi on the Kamchatka Peninsula, was formed about 4,700 years ago over a late-Pleistocene lava-dome complex and an edifice built about 11,000-7,000 years ago. Three periods of intensified activity have occurred during the past 3,000 years. The latest period, which was preceded by a 1,000-year quiescence, began with the dramatic 1955-56 eruption. This eruption, similar to that of St. Helens in 1980, produced a large open crater that was formed by collapse of the summit and an associated lateral blast. Subsequent episodic but ongoing lava-dome growth, accompanied by intermittent explosive activity and pyroclastic flows, has largely filled the 1956 crater. 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qthlGMr4qA$> Dukono | Indonesia | 1.6992°N, 127.8783°E | Summit elev. 1273 m Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Dukono was ongoing during 25 September-1 October. Daily dense gray-and-white ash plumes rose 100-800 m above the summit and drifted W and NW. The Alert Level remained at Level 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone. Geologic Summary. Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, have occurred since 1933. During a major eruption in 1550 CE, a lava flow filled in the strait between Halmahera and the N-flank Gunung Mamuya cone. This complex volcano presents a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also been active during historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtg7cT-YCQ$> Ebeko | Russia | 50.686°N, 156.014°E | Summit elev. 1103 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that moderate explosive activity was ongoing at Ebeko during 19-26 September. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E), explosions during 19, 21, and 24-25 September generated ash plumes that rose as high as 2 km (6,600 ft) a.s.l. and drifted NE, E, and SE. Thermal anomalies were identified in satellite images on 23 and 26 September; on other days 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qthlGMr4qA$> Etna | Italy | 37.748°N, 14.999°E | Summit elev. 3357 m Sezione di Catania - Osservatorio Etneo (INGV) reported that continuous gas emissions rose from Etnaâ??s summit craters during 23-29 September. Explosive activity at NE Crater that began at around 2300 on 23 September continued through the week, though with less frequently, based on webcam images. Geologic Summary. Mount Etna, towering above Catania on the island of Sicily, has one of the world's longest documented records of volcanism, dating back to 1500 BCE. Historical lava flows of basaltic composition cover much of the surface of this massive volcano, whose edifice is the highest and most voluminous in Italy. The Mongibello stratovolcano, truncated by several small calderas, was constructed during the late Pleistocene and Holocene over an older shield volcano. The most prominent morphological feature of Etna is the Valle del Bove, a 5 x 10 km caldera open to the east. Two styles of eruptive activity typically occur, sometimes simultaneously. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more summit craters. Flank vents, typically with higher effusion rates, are less frequently active and originate from fissures that open progressively downward from near the summit (usually accompanied by Strombolian eruptions at the upper end). Cinder cones are commonly constructed over the vents of lower-flank lava flows. Lava flows extend to the foot of the volcano on all sides and have reached the sea over a broad area on the SE flank. Source: Sezione di Catania - Osservatorio Etneo (INGV) http://www.ct.ingv.it/ <https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtjxRNxSjg$> Great Sitkin | United States | 52.076°N, 176.13°W | Summit elev. 1740 m Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick lava flow in Great Sitkinâ??s summit crater during 24 September-1 October. The lava flow had filled most of the summit crater. The local seismic network continued to detect small earthquakes and other signals associated with the ongoing eruption. 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtiIaA6-yg$> Ibu | Indonesia | 1.488°N, 127.63°E | Summit elev. 1325 m Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity at Ibu continued during 25 September-1 October with multiple daily eruptive events. Daily gray or white-and-gray ash plumes that were sometimes dense rose as high as 1.5 km above the summit and drifted in multiple directions. Webcam images posted with the reports showed incandescence visible above the crater rim. The Alert Level remained at 3 (the second highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 5 km away from the N crater wall opening. Geologic Summary. The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, has contained several small crater lakes. The 1.2-km-wide outer crater is breached on the N, creating a steep-walled valley. A large cone grew ENE of the summit, and a smaller one to the WSW has fed a lava flow down the W flank. A group of maars is located below the N and W flanks. The first observed and recorded eruption was a small explosion from the summit crater in 1911. Eruptive activity began again in December 1998, producing a lava dome that eventually covered much of the floor of the inner summit crater along with ongoing explosive ash emissions. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtg7cT-YCQ$> Karymsky | Russia | 54.049°N, 159.443°E | Summit elev. 1513 m Kamchatkan Volcanic Eruption Response Team (KVERT) reported moderate levels of activity at Karymsky during 19-26 September. A minor thermal anomaly over the volcano was identified in satellite images during 22-23 and 25-26 September; weather clouds obscured 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qthlGMr4qA$> Lewotobi | Indonesia | 8.542°S, 122.775°E | Summit elev. 1703 m Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Lewotobiâ??s Laki-laki volcano continued during 25 September-1 October from a vent on the upper NW flank. Daily gray or white-and-gray ash plumes that were sometimes dense rose as high as 1.2 km above the summit and drifted SW, W, NW, and N. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3 km radius around both Laki-laki and Perempuan craters, 4 km to the NNW and SSE of Laki-laki. Geologic Summary. The Lewotobi edifice in eastern Flores Island is composed of the two adjacent Lewotobi Laki-laki and Lewotobi Perempuan stratovolcanoes (the "husband and wife"). Their summits are less than 2 km apart along a NW-SE line. The conical Laki-laki to the NW has been frequently active during the 19th and 20th centuries, while the taller and broader Perempuan has had observed eruptions in 1921 and 1935. Small lava domes have grown during the 20th century in both of the summit craters, which are open to the north. A prominent cone, Iliwokar, occurs on the E flank of Perampuan. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtg7cT-YCQ$> Manam | Papua New Guinea | 4.08°S, 145.037°E | Summit elev. 1807 m The Darwin VAAC reported that during 0000-0600 on 29 September ash plumes from Manam were identified in satellite images rising 2.4 km (8,000 ft) a.s.l. and drifting NW. At 0230 on 1 October an ash plume rose 4 km (13,000 ft) a.s.l. and drifted S. 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtjrytviuw$> Merapi | Indonesia | 7.54°S, 110.446°E | Summit elev. 2910 m Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 20-26 September. Seismicity was less intense compared to the previous week. The SW lava dome produced 204 lava avalanches that traveled as far as 1.8 km down the Bebeng drainage on the SW flank. Five pyroclastic flows descended the Bebeng as far as 1.2 km. Morphological changes to the SW lava dome were due to continuing effusion and collapses of material. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location. Geologic Summary. Merapi, one of Indonesia's most active volcanoes, lies in one of the world's most densely populated areas and dominates the landscape immediately north of the major city of Yogyakarta. It is the youngest and southernmost of a volcanic chain extending NNW to Ungaran volcano. Growth of Old Merapi during the Pleistocene ended with major edifice collapse perhaps about 2,000 years ago, leaving a large arcuate scarp cutting the eroded older Batulawang volcano. Subsequent growth of the steep-sided Young Merapi edifice, its upper part unvegetated due to frequent activity, began SW of the earlier collapse scarp. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated lands on the western-to-southern flanks and caused many fatalities. Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) http://www.merapi.bgl.esdm.go.id/ <https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtj3EpRxrg$> 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 24-30 September. The number of seismic events associated with fluid movement increased in both magnitude and number compared to the previous week but were variable between low and moderate levels throughout the week. Webcam images confirmed ash emissions associated with some of these events along with occasional ejections of hotter material. Ash plumes rose as high as 2 km above the crater rim and drifted NW and WNW during the first half of the week and N, E, and SE during the second half of the week. Ashfall was reported in Cabaña de Brisas (NW) and in areas to the E around the Lagunilla River. Seismicity associated with rock fracturing increased in the number of events, though their magnitudes were comparable to the previous week; these earthquakes, with depths ranging from less than 1 km down to 8 km below the summit, were primarily located within 4 km SSW, S, SE, and SE of Arenas Crater. The largest event was an M 1 which was detected at 2131 on 28 September and located about 2 km SSE and 4 km deep. Sulfur dioxide emissions were variable, and drift directions were not towards measuring stations; satellite measurements indicated increased emissions and a high value on 29 September that had not been recorded since February 2023. Low-to-moderate thermal anomalies on the crater floor were identified in satellite data. 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qth-NB3w3Q$> Nyamulagira | DR Congo | 1.408°S, 29.2°E | Summit elev. 3058 m A 28 September satellite image showed some minor advancement (around 200 m) of the W branch of Nyamuragiraâ??s NNW lava flow compared to an 18 September image. Small thermal anomalies were concentrated near the end of the NNW lava flow and at the end of the W branch, and a few were located along the flow about of a third of the way up the flank. A thermal anomaly was present the part of the eastern crater floor. A few small thermal anomalies on the W flank flow were visible, though weather clouds obscured most of W flank. Weather clouds also obscured part of the summit crater and the upper NNW flow. Geologic Summary. Africa's most active volcano, Nyamulagira (also known as Nyamuragira), is a massive high-potassium basaltic shield about 25 km N of Lake Kivu and 13 km NNW of the steep-sided Nyiragongo volcano. The summit is truncated by a small 2 x 2.3 km caldera that has walls up to about 100 m high. Documented eruptions have occurred within the summit caldera, as well as from the numerous flank fissures and cinder cones. A lava lake in the summit crater, active since at least 1921, drained in 1938, at the time of a major flank eruption. Recent lava flows extend down the flanks more than 30 km from the summit as far as Lake Kivu; extensive lava flows from this volcano have covered 1,500 km2 of the western branch of the East African Rift. Source: Copernicus https://www.copernicus.eu/en <https://urldefense.com/v3/__https://www.copernicus.eu/en__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtg1sWTxTw$> Popocatepetl | Mexico | 19.023°N, 98.622°W | Summit elev. 5393 m Centro Nacional de Prevención de Desastres (CENAPRED) reported that eruptive activity continued at Popocatépetl during 24 September-1 October. Weather clouds sometimes prevented visual observations. The seismic network recorded 9-58 long-period events per day that were accompanied by steam-and-gas emissions; emissions contained minor amounts of ash during 29-30 September. The seismic network also recorded daily tremor with periods lasting from 57 minutes up to five hours and nine minutes, and a period of emissions that lasted 18 minutes during 27-28 September. According to the Washington VAAC ash plumes visible in webcam and satellite images on 28 September rose to 6.7 km (22,000 ft) a.s.l. (or about 1.3 km above the crater rim) and drifted NW and NE. The Alert Level remained at Yellow, Phase Two (the middle level on a three-color scale) and the public was warned to stay 12 km away from the crater. Geologic Summary. Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, rises 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 400 x 600 m wide crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano. At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas to the south. The modern volcano was constructed south of the late-Pleistocene to Holocene El Fraile cone. Three major Plinian eruptions, the most recent of which took place about 800 CE, have occurred since the mid-Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since Pre-Columbian time. Sources: Centro Nacional de Prevencion de Desastres (CENAPRED) https://www.gob.mx/cenapred <https://urldefense.com/v3/__https://www.gob.mx/cenapred__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qthwSwopUg$> ; Washington Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/messages.html <https://urldefense.com/v3/__http://www.ssd.noaa.gov/VAAC/messages.html__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qthBvYuI4A$> Reventador | Ecuador | 0.077°S, 77.656°W | Summit elev. 3562 m Instituto GeofÃsico-Escuela Politécnica Nacional (IG-EPN) reported that an eruption at Reventador was ongoing during 24 September-1 October. Signals from the seismic stations were not transmitted during the first half of the week; during 28 September-1 October seismicity was characterized by 79-105 daily explosions, long-period earthquakes, harmonic tremor, and tremor associated with emissions. Ash-and-gas plumes were observed in webcam images and/or satellite images rising as high as 1.1 km above the crater rim and drifting NW, WNW, and W. Webcams occasionally did not transmit data and weather conditions sometimes obscured views. Thermal anomalies in the crater were identified in satellite images on most days. SecretarÃa de Gestión de Riesgos maintained the Alert Level at Orange (the second highest level on a four-color scale). Geologic Summary. Volcán El Reventador is the most frequently active of a chain of Ecuadorian volcanoes in the Cordillera Real, well east of the principal volcanic axis. The forested, dominantly andesitic stratovolcano has 4-km-wide avalanche scarp open to the E formed by edifice collapse. A young, unvegetated, cone rises from the amphitheater floor to a height comparable to the rim. It has been the source of numerous lava flows as well as explosive eruptions visible from Quito, about 90 km ESE. Frequent lahars in this region of heavy rainfall have left extensive deposits on the scarp slope. The largest recorded eruption took place in 2002, producing a 17-km-high eruption column, pyroclastic flows that traveled up to 8 km, and lava flows from summit and flank vents. Sources: Instituto GeofÃsico-Escuela Politécnica Nacional (IG-EPN) http://www.igepn.edu.ec/ <https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtgAgOV7YQ$> ; SecretarÃa de Gestión de Riesgos (SGR) http://www.gestionderiesgos.gob.ec/ <https://urldefense.com/v3/__http://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtjni_ht0A$> Rincon de la Vieja | Costa Rica | 10.83°N, 85.324°W | Summit elev. 1916 m Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) reported that small phreatic eruptions at Rincón de la Vieja were recorded at 1715, 2225, and 2248 on 26 September, at 0538 on 27 September, and at 2200 on 29 September. Emissions from the events did not contain ash. Geologic Summary. Rincón de la Vieja, the largest volcano in NW Costa Rica, is a remote volcanic complex in the Guanacaste Range. The volcano consists of an elongated, arcuate NW-SE-trending ridge constructed within the 15-km-wide early Pleistocene GuachipelÃn caldera, whose rim is exposed on the south side. Sometimes known as the "Colossus of Guanacaste," it has an estimated volume of 130 km3 and contains at least nine major eruptive centers. Activity has migrated to the SE, where the youngest-looking craters are located. The twin cone of Santa MarÃa volcano, the highest peak of the complex, is located at the eastern end of a smaller, 5-km-wide caldera and has a 500-m-wide crater. A Plinian eruption producing the 0.25 km3 RÃo Blanca tephra about 3,500 years ago was the last major magmatic eruption. All subsequent eruptions, including numerous historical eruptions possibly dating back to the 16th century, have been from the prominent active crater containing a 500-m-wide acid lake located ENE of Von Seebach crater. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) http://www.ovsicori.una.ac.cr/ <https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtiSnZNN6w$> Sabancaya | Peru | 15.787°S, 71.857°W | Summit elev. 5960 m Instituto GeofÃsico del Perú (IGP) reported that the eruption at Sabancaya continued during 23-29 September with a daily average of 18 explosions. Gas-and-ash plumes rose as high as 2.3 km above the summit and drifted less than 10 km SE and S. Thermal anomalies over the lava dome in the summit crater were identified in satellite data. Slight inflation was detected N of Hualca Hualca (7 km N). Sulfur dioxide emissions were at moderate levels, averaging 729 tons per day. The Alert Level remained at Orange (the third level on a four-color scale) and the public was warned to stay outside of a 12 km radius. Geologic Summary. Sabancaya, located in the saddle NE of Ampato and SE of Hualca Hualca volcanoes, is the youngest of these volcanic centers and the only one to have erupted in historical time. The oldest of the three, Nevado Hualca Hualca, is of probable late-Pliocene to early Pleistocene age. The name Sabancaya (meaning "tongue of fire" in the Quechua language) first appeared in records in 1595 CE, suggesting activity prior to that date. Holocene activity has consisted of Plinian eruptions followed by emission of voluminous andesitic and dacitic lava flows, which form an extensive apron around the volcano on all sides but the south. Records of observed eruptions date back to 1750 CE. Source: Instituto GeofÃsico del Perú (IGP) http://www.igp.gob.pe/ <https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtgtr92gyw$> Semeru | Indonesia | 8.108°S, 112.922°E | Summit elev. 3657 m Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity continued at Semeru during 25 September-1 October with multiple daily eruptive events recorded by the seismic network. White-and-gray ash plumes that were sometimes dense rose 100-600 m above the summit and drifted NW, W, SW, and S; eruptive events were recorded on 27 September, but no emissions were observed. 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtg7cT-YCQ$> Sheveluch | Russia | 56.653°N, 161.36°E | Summit elev. 3283 m Kamchatkan Volcanic Eruption Response Team (KVERT) reported that during 19-26 September lava extrusion likely continued at Sheveluchâ??s â??300 years of RASâ?? dome on the SW flank of Old Sheveluch and at the dome at Young Sheveluch. Daily thermal anomalies over the domes were identified in satellite images. Plumes of resuspended ash drifted 1,500 km E during 25-26 September. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. The high, isolated massif of Sheveluch volcano (also spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group. The 1,300 km3 andesitic volcano is one of Kamchatka's largest and most active volcanic structures, with at least 60 large eruptions during the Holocene. The summit of roughly 65,000-year-old Stary Shiveluch is truncated by a broad 9-km-wide late-Pleistocene caldera breached to the south. Many lava domes occur on its outer flanks. The Molodoy Shiveluch lava dome complex was constructed during the Holocene within the large open caldera; Holocene lava dome extrusion also took place on the flanks of Stary Shiveluch. Widespread tephra layers from these eruptions have provided valuable time markers for dating volcanic events in Kamchatka. Frequent collapses of dome complexes, most recently in 1964, have produced debris avalanches whose deposits cover much of the floor of the breached caldera. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qthlGMr4qA$> Stromboli | Italy | 38.789°N, 15.213°E | Summit elev. 924 m Sezione di Catania - Osservatorio Etneo (INGV) reported that eruptive activity continued at Stromboli during 23-29 September. Webcam images showed Strombolian activity at two vents in Area N within the upper part of the Sciara del Fuoco and from at least two vents in Area C-S (South-Central Crater) on the crater terrace. The vents in Area N continued to produce explosions at a rate of 3-15 events per hour, ejecting lapilli and bombs less than 80 m above the vents. Spattering was observed that was intense on 23 and 26 September. Explosions at the vent in Area C-S mainly occurred at a rate of 1-5 events per hour during 26-28 September and ejected tephra over 250 m above the vent. The Alert Level remained at Yellow (the second lowest level on a four-level scale). Geologic Summary. Spectacular incandescent nighttime explosions at Stromboli have long attracted visitors to the "Lighthouse of the Mediterranean" in the NE Aeolian Islands. This volcano has lent its name to the frequent mild explosive activity that has characterized its eruptions throughout much of historical time. The small island is the emergent summit of a volcano that grew in two main eruptive cycles, the last of which formed the western portion of the island. The Neostromboli eruptive period took place between about 13,000 and 5,000 years ago. The active summit vents are located at the head of the Sciara del Fuoco, a prominent scarp that formed about 5,000 years ago due to a series of slope failures which extends to below sea level. The modern volcano has been constructed within this scarp, which funnels pyroclastic ejecta and lava flows to the NW. Essentially continuous mild Strombolian explosions, sometimes accompanied by lava flows, have been recorded for more than a millennium. Source: Sezione di Catania - Osservatorio Etneo (INGV) http://www.ct.ingv.it/ <https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtjxRNxSjg$> Suwanosejima | Japan | 29.638°N, 129.714°E | Summit elev. 796 m Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 23-30 September. Crater incandescence was observed nightly in webcam images. Explosions were recorded by the seismic network at 0337, 0428, 0730, and 1720 on 25 September, at 1415 and 1554 on 26 September, and at 1810 on 28 September. The explosions generated ash-and-gas plumes that rose 1-1.6 km above the crater rim and drifted mainly W and SW. Eruptive events during 24-28 and 30 September produced ash-and-gas plumes that rose 1-1.6 km above the crater rim and drifted and drifted mainly W and SW. Occasional ashfall was reported at the Suwanosejima Branch Office in Toshima village (3.5 km SSW), though dates were unspecified. 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!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qtiHAZVp2A$> Yasur | Vanuatu | 19.532°S, 169.447°E | Summit elev. 361 m On 26 September the Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a level of â??major unrest,â?? as defined by the Alert Level 2 status (on a scale of 0-5). Recent visual observations, webcam mages, and photos taken in the field indicated that explosions continued, producing emissions of gas, steam, and/or ash. Gas emissions and thermal anomalies were identified in satellite images. The report warned that some of the explosions may eject material that falls in and around the crater. The public was reminded to not enter the restricted area within 600 m around the boundaries of the Permanent Exclusion Zone, defined by Danger Zone A on the hazard map. Geologic Summary. Yasur has exhibited essentially continuous Strombolian and Vulcanian activity at least since Captain Cook observed ash eruptions in 1774. This style of activity may have continued for the past 800 years. Located at the SE tip of Tanna Island in Vanuatu, this pyroclastic cone has a nearly circular, 400-m-wide summit crater. The active cone is largely contained within the small Yenkahe caldera, and is the youngest of a group of Holocene volcanic centers constructed over the down-dropped NE flank of the Pleistocene Tukosmeru volcano. The Yenkahe horst is located within the Siwi ring fracture, a 4-km-wide open feature associated with eruption of the andesitic Siwi pyroclastic sequence. Active tectonism along the Yenkahe horst accompanying eruptions has raised Port Resolution harbor more than 20 m during the past century. Source: Vanuatu Meteorology and Geohazards Department (VMGD) http://www.geohazards.gov.vu/ <https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!Z-GAVw581OLRMpuF3ofAGFyfguji1UcUUwt-fTu-jYT6P6KatbWuzxJDEkoe4GjemsjsRHw5Cs50svw2qthWjHJwfQ$> 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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