3-3-3-3-3-3-3-3-3-3-3-3-3 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 29 January-4 February 2025 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lG6YwGZTA$> New Activity/Unrest: Bezymianny, Russia | Kilauea, United States | Kolumbo, Greece | Poas, Costa Rica | Purace, Colombia Ongoing Activity: Ahyi, United States | Aira, Japan | Ambae, Vanuatu | Ambrym, Vanuatu | Awu, Indonesia | Dukono, Indonesia | Ebeko, Russia | Great Sitkin, United States | Ibu, Indonesia | Kanlaon, Philippines | Karymsky, Russia | Lewotobi, Indonesia | Lokon-Empung, Indonesia | Merapi, Indonesia | Popocatepetl, Mexico | Semeru, Indonesia | Sheveluch, Russia | Stromboli, Italy | Suwanosejima, Japan | Ubinas, Peru | 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 Bezymianny | Russia | 55.972°N, 160.595°E | Summit elev. 2882 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that a large thermal anomaly over Bezymianny was identified in satellite images overnight during 30-31 January. Intense gas-and-steam emissions were also occurring. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale). Satellite images on 3 February again showed a large thermal anomaly. Dates are reported in UTC; specific events are in local time where noted. 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGE1L6bKg$> Kilauea | United States | 19.421°N, 155.287°W | Summit elev. 1222 m The Hawaiian Volcano Observatory (HVO) reported that the eruption within Kilaueaâ??s Kaluapele summit caldera continued during 29 January-4 February from vents along the SW margin of Halemaâ??umaâ??u Crater. Small areas of incandescence from the cooling lava on the crater floor and at the vents were visible during 29-31 January and infrequent spatter occurred at the vents during 31 January-2 February. A phase of small sporadic fountaining that began the evening of 2 February intensified during the afternoon of 3 February. Fountains at the N vent became sustained by 2250 and within an hour they grew from 15 m to over 80 m high. Multiple lava flows emerged from the N vent at 2152 and had covered about 15-20 percent of the crater floor by 2250. Fountains rose as high as 100 m during the most intense phase. Lava fountaining began at the S vent at 2350. Fountaining from both the N and S vents was visible overnight during 3-4 February. At 0920 on 4 February fountains rose 40-50 m at the N vent and 25-35 m at the S vent. Lava covered the entire crater floor. 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. Kilauea overlaps the E flank of the massive Mauna Loa shield volcano in the island of Hawaii. Eruptions are prominent in Polynesian legends; written documentation since 1820 records frequent summit and flank lava flow eruptions interspersed with periods of long-term lava lake activity at Halemaumau crater in the summit caldera until 1924. The 3 x 5 km caldera was formed in several stages about 1,500 years ago and during the 18th century; eruptions have also originated from the lengthy East and Southwest rift zones, which extend to the ocean in both directions. About 90% of the surface of the basaltic shield volcano is formed of lava flows less than about 1,100 years old; 70% of the surface is younger than 600 years. The long-term eruption from the East rift zone between 1983 and 2018 produced lava flows covering more than 100 km2, destroyed hundreds of houses, and added new coastline. Source: US Geological Survey Hawaiian Volcano Observatory (HVO) https://volcanoes.usgs.gov/observatories/hvo/ <https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lEOctg-_g$> Kolumbo | Greece | 36.524°N, 25.483°E | Summit elev. -18 m According to the Ministry for Climate Crisis and Civil Protection, Greece, press release on 29 January, seismicity increased near Santorini, along the central Kameni fault in the N part of the caldera. Seismicity intensified and shifted NE to an area between the islands of Thira and Amorgos along a NE-SW-trending fault; during 31 January-1 February the largest earthquake was a M 4.3. The submarine Kolumbo volcano is located along that fault line, about 7 km NE of Santorini, though at the time scientists attributed the seismicity to tectonic activity. The Geodynamic Institute of the National Observatory of Athens reported more than 31,000 recorded earthquakes in that area, in a zone extending 15 km long, during 1-4 February, including 630 located events at depths of 2-18 km; events consisted of 155 at M 3.5-3.9, 48 at M 4-4.4, 21 at M 4.5-4.9, and one at M 5. During 4-5 February seismicity extended along an area about 30 km long. The seismicity was similar to a seismic crisis during 2010-2012 that did not lead to a volcanic eruption, though the previous activity was more intense and with larger average earthquake magnitudes. According to news articles schools on islands including Santorini, Thira, Anafi, Ios, Amorgos, Mykonos, Leros, Syros, and Patmos were closed on 2 February through at least 4 February. Gatherings in enclosed spaces within Municipality of Thira were cancelled. By 3 February more than 11,000 people had left Santorini by ferry or plane, and additional flights to the islands were being scheduled to assist moving people to Athens. Geologic Summary. The submarine Kolumbo volcano is about 15 km NE of the center of the Santorini caldera. Although previously considered to be part of a volcanic field associated with Santorini along a fault zone, Klaver et al. (2016) concluded that Kolumbo was a distinct volcanic system with "a deep differentiation history" based on "a signature of high 208Pb/206Pb compared to Santorini". A strong eruption during September-November 1650 CE killed over 60 people, along with livestock, due to toxic gas emissions; ashfall reached mainland Turkey, and an island of pumice rose above sea level but was rapidly eroded. Klaver et al. (2016) describe the current crater as roughly oval-shaped with a diameter of ~1.7 km, with the crater floor at 500 m below sea level, and the highest point of the crater rim at -18 m. A chain of 19 smaller volcanic features extends ~10 km NE from this primary crater. Sources: CNN https://www.cnn.com/2025/02/02/travel/santorini-earthquake-greece-intl/index.html <https://urldefense.com/v3/__https://www.cnn.com/2025/02/02/travel/santorini-earthquake-greece-intl/index.html__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lHp8Cn5dQ$> ; CBS News https://www.cbsnews.com/news/greece-earthquakes-santorini-island/?intcid=CNR-02-0623 <https://urldefense.com/v3/__https://www.cbsnews.com/news/greece-earthquakes-santorini-island/?intcid=CNR-02-0623__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lHxRbAh1A$> ; BBC News https://www.bbc.com/news/articles/cjde94dnj08o <https://urldefense.com/v3/__https://www.bbc.com/news/articles/cjde94dnj08o__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGrwHK4rg$> ; Greek City Times https://greekcitytimes.com/2025/02/03/seismic-activity-near-santorini-expert-analysis-and-precautionary-measures/ <https://urldefense.com/v3/__https://greekcitytimes.com/2025/02/03/seismic-activity-near-santorini-expert-analysis-and-precautionary-measures/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lEv0diqTA$> ; National Observatory of Athens https://www.noa.gr/ <https://urldefense.com/v3/__https://www.noa.gr/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lEjs6NEOQ$> ; Ministry for Climate Crisis and Civil Protection https://civilprotection.gov.gr/ <https://urldefense.com/v3/__https://civilprotection.gov.gr/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGNqja07g$> Poas | Costa Rica | 10.2°N, 84.233°W | Summit elev. 2697 m The Observatorio Vulcanológico y Sismológico de Costa Rica-Universidad Nacional (OVSICORI-UNA) reported that small eruptions at Poás ejecting water and steam were recorded by seismic and infrasound sensors at 0038 and 0450 on 28 January and at 0643 on 29 January. The lake water was milky-gray in color and intense gas-and-steam emissions rose from the waterâ??s surface due to fumarolic activity on the crater floor and convecting water. Gas monitoring instruments on the W crater rim detected significant amounts of hydrogen sulfide and sulfur dioxide. The report noted that during January webcams recorded several bubbles from Boca A (SW part of the lake) on the surface of the lake and upwelling of bubbles from Boca C (central part of lake). Volcanologists directly observed these bubbles at 1055 and 1206 on 29 January; sulfur dioxide emissions averaged 384 tons per day. Gas emissions were lower on 30 January and two vigorous convection cells in the lake over both Boca A and Boca C were visible during 30-31 January. During 2-4 February gas emissions fluctuated between low and high values and bubbles or convection cells were active over both vents. Geologic Summary. The broad vegetated edifice of Poás, one of the most active volcanoes of Costa Rica, contains three craters along a N-S line. The frequently visited multi-hued summit crater lakes of the basaltic-to-dacitic volcano are easily accessible by vehicle from the nearby capital city of San José. A N-S-trending fissure cutting the complex stratovolcano extends to the lower N flank, where it has produced the Congo stratovolcano and several lake-filled maars. The southernmost of the two summit crater lakes, Botos, last erupted about 7,500 years ago. The more prominent geothermally heated northern lake, Laguna Caliente, is one of the world's most acidic natural lakes, with a pH of near zero. It has been the site of frequent phreatic and phreatomagmatic eruptions since an eruption was reported in 1828. Eruptions often include geyser-like ejections of crater-lake water. Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) http://www.ovsicori.una.ac.cr/ <https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGgBArKfw$> Purace | Colombia | 2.3095°N, 76.3948°W | Summit elev. 4650 m The Servicio Geologico Colombiano (SGC) reported that a M 1.7 earthquake indicating rock fracturing occurred at 1700 on 1 February and was located 2 km below the Puracé cone. On 2 February there was an increase in tremor and long-period events with signals located less than 2 km beneath the cone. Deformation data did not show any significant movement and gas emissions were unchanged. The Alert Level remained at Yellow (the second lowest level on a four-color scale). Geologic Summary. Puracé is an active andesitic volcano with a 600-m-diameter summit crater at the NW end of the Los Coconucos Volcanic Chain. This volcanic complex includes nine composite and five monogenetic volcanoes, extending from the Puracé crater more than 6 km SE to the summit of Pan de Azúcar stratovolcano. The dacitic massif which the complex is built on extends about 13 km NW-SE and 10 km NE-SW. Frequent small to moderate explosive eruptions reported since 1816 CE have modified the morphology of the summit crater, with the largest eruptions in 1849, 1869, and 1885. 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lHBoR5h1g$> Ongoing Activity Ahyi | United States | 20.42°N, 145.03°E | Summit elev. -75 m Unrest at Ahyi Seamount continued through 31 January. Satellite images showed a plume of discolored water in the vicinity of the seamount on 27 and 29 January, indicating possible submarine activity. No signals coming from the direction of Ahyi were identified in data from underwater pressure sensors near Wake Island (about 2,270 km E of Ahyi). The Aviation Color Code remained at Yellow (the second lowest level on a four-color scale) and the Volcano Alert Level remained at Advisory (the second lowest level on a four-level scale). Geologic Summary. Ahyi seamount is a large conical submarine volcano that rises to within 75 m of the ocean surface ~18 km SE of the island of Farallon de Pajaros in the northern Marianas. Water discoloration has been observed there, and in 1979 the crew of a fishing boat felt shocks over the summit area, followed by upwelling of sulfur-bearing water. On 24-25 April 2001 an explosive eruption was detected seismically by a station on Rangiroa Atoll, Tuamotu Archipelago. The event was well constrained (+/- 15 km) at a location near the southern base of Ahyi. An eruption in April-May 2014 was detected by NOAA divers, hydroacoustic sensors, and seismic stations. Source: US Geological Survey https://www.usgs.gov/ <https://urldefense.com/v3/__https://www.usgs.gov/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lFbNpvuSg$> Aira | Japan | 31.5772°N, 130.6589°E | Summit elev. 1117 m The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Calderaâ??s Sakurajima volcano) during 27 January-3 February. Nightly crater incandescence was visible in webcam images. Eruptive events recorded during 17 and 30-31 January produced ash plumes that rose 0.8-1.7 km above the crater rim and drifted E and SE. Ash plumes were continuous during 2043-2050 on 30 January. Explosions at 2013 on 30 January, at 1548 on 31 January, and at 1610 on 3 February generated ash plumes that rose 0.8-1.5 km above the crater rim and drifted SE. The explosion at 1548 on 31 January also ejected large blocks 300-500 m from the crater rim. 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lH7MdAzHQ$> Ambae | Vanuatu | 15.389°S, 167.835°E | Summit elev. 1496 m On 30 January the Vanuatu Meteorology and Geohazards Department (VMGD) reported that steam-and-gas emissions from the active vents at Ambae were ongoing during January based on satellite images. A low-level thermal anomaly was identified in satellite data on 17 January indicating an increase in surface temperatures. Seismic data also confirmed ongoing unrest. The Alert Level remained at 2 (on a scale of 0-5), and the public was warned to stay outside of the Danger Zone, defined as a 2-km radius around the active vents in Lake Voui, and away from drainages during heavy rains. Geologic Summary. The island of Ambae, also known as Aoba, is a massive 2,500 km3 basaltic shield that is the most voluminous volcano of the New Hebrides archipelago. A pronounced NE-SW-trending rift zone with numerous scoria cones gives the 16 x 38 km island an elongated form. A broad pyroclastic cone containing three crater lakes (Manaro Ngoru, Voui, and Manaro Lakua) is located at the summit within the youngest of at least two nested calderas, the largest of which is 6 km in diameter. That large central edifice is also called Manaro Voui or Lombenben volcano. Post-caldera explosive eruptions formed the summit craters about 360 years ago. A tuff cone was constructed within Lake Voui (or Vui) about 60 years later. The latest known flank eruption, about 300 years ago, destroyed the population of the Nduindui area near the western coast. Source: Vanuatu Meteorology and Geohazards Department (VMGD) http://www.geohazards.gov.vu/ <https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lHa3CchCg$> Ambrym | Vanuatu | 16.25°S, 168.12°E | Summit elev. 1334 m On 30 January the Vanuatu Meteorology and Geohazards Department (VMGD) reported ongoing fumarolic activity at Ambrym from both Benbow and Marum craters based on webcam images. Seismic data confirmed ongoing unrest. The Alert Level remained at 2 (on a scale of 0-5). VMGD warned the public to stay outside of Permanent Danger Zone A, defined as a 1-km radius around Benbow Crater and a 2-km radius around Marum Crater, and to stay 500 m away from the ground cracks created by the December 2018 eruption. Geologic Summary. Ambrym, a large basaltic volcano with a 12-km-wide caldera, is one of the most active volcanoes of the New Hebrides Arc. A thick, almost exclusively pyroclastic sequence, initially dacitic then basaltic, overlies lava flows of a pre-caldera shield volcano. The caldera was formed during a major Plinian eruption with dacitic pyroclastic flows about 1,900 years ago. Post-caldera eruptions, primarily from Marum and Benbow cones, have partially filled the caldera floor and produced lava flows that ponded on the floor or overflowed through gaps in the caldera rim. Post-caldera eruptions have also formed a series of scoria cones and maars along a fissure system oriented ENE-WSW. Eruptions have apparently occurred almost yearly during historical time from cones within the caldera or from flank vents. However, from 1850 to 1950, reporting was mostly limited to extra-caldera eruptions that would have affected local populations. Source: Vanuatu Meteorology and Geohazards Department (VMGD) http://www.geohazards.gov.vu/ <https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lHa3CchCg$> Awu | Indonesia | 3.689°N, 125.447°E | Summit elev. 1318 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi reported that seismicity at Awu had decreased. Swarms of both deep and shallow volcanic earthquakes continued to occur but at decreasing frequency; the last swarm occurred during 1807-1817 on 31 January and consisted of nine shallow volcanic earthquakes. Tiltmeter data from the Kolongan station indicated continuing inflation of the volcano. Emissions continued to rose 10-200 m above the summit and had not significantly changed since July 2024. At 0600 on 2 February the Alert Level was lowered to 2 (on a scale of 1-4) and the public was warned to stay 3 km away from the craterâ??s center. Geologic Summary. The massive Gunung Awu stratovolcano occupies the northern end of Great Sangihe Island, the largest of the Sangihe arc. Deep valleys that form passageways for lahars dissect the flanks of the volcano, which was constructed within a 4.5-km-wide caldera. Powerful explosive eruptions in 1711, 1812, 1856, 1892, and 1966 produced devastating pyroclastic flows and lahars that caused more than 8000 cumulative fatalities. Awu contained a summit crater lake that was 1 km wide and 172 m deep in 1922, but was largely ejected during the 1966 eruption. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGz76aFBg$> Dukono | Indonesia | 1.6992°N, 127.8783°E | Summit elev. 1273 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Dukono was ongoing during 29 January-4 February. Daily white-and-gray ash plumes rose 100-800 m above the crater rim and drifted in multiple directions. Occasional thumping noises were reported during 31 January-1 February. The Alert Level remained at Level 2 (on a scale of 1-4) and the public was warned to stay 4 km away from the Malupang Warirang Crater. 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGz76aFBg$> Ebeko | Russia | 50.686°N, 156.014°E | Summit elev. 1103 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that eruptive activity at Ebeko was last observed on 31 December 2024, and since then only moderate levels of steam-and-gas activity had been observed. On 23 January the Aviation Color Code was lowered to Yellow (the second lowest level on a four-color scale). Dates are UTC; specific events are in local time where noted. Geologic Summary. The flat-topped summit of the central cone of Ebeko volcano, one of the most active in the Kuril Islands, occupies the northern end of Paramushir Island. Three summit craters located along a SSW-NNE line form Ebeko volcano proper, at the northern end of a complex of five volcanic cones. Blocky lava flows extend west from Ebeko and SE from the neighboring Nezametnyi cone. The eastern part of the southern crater contains strong solfataras and a large boiling spring. The central crater is filled by a lake about 20 m deep whose shores are lined with steaming solfataras; the northern crater lies across a narrow, low barrier from the central crater and contains a small, cold crescentic lake. Historical activity, recorded since the late-18th century, has been restricted to small-to-moderate explosive eruptions from the summit craters. Intense fumarolic activity occurs in the summit craters, on the outer flanks of the cone, and in lateral explosion craters. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGE1L6bKg$> Great Sitkin | United States | 52.076°N, 176.13°W | Summit elev. 1740 m The Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick lava flow in Great Sitkinâ??s summit crater during 29 January-4 February. Cloudy satellite and webcam images prevented clear observations. 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lFVevt0ng$> Ibu | Indonesia | 1.488°N, 127.63°E | Summit elev. 1325 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that the eruption at Ibu continued during 29 January-4 February. Multiple daily gray or white-and-gray ash plumes that were often dense rose as high as 1.5 km above the summit and drifted mainly NW, W, SW, and S. Webcam images posted with the reports often showed incandescence at the summit. On 29 January BNPB reported that evacuees will start returning to their homes due to the decrease in the exclusion zone announced the previous day. As many as 541 families, or 1,425 people, that were spread across nine evacuation centers will return home after officials check for safe conditions and that basic needs will be met. The Alert Level remained at 3 (the second highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 5 km away from the N crater wall opening. Geologic Summary. The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, has contained several small crater lakes. The 1.2-km-wide outer crater is breached on the N, creating a steep-walled valley. A large cone grew ENE of the summit, and a smaller one to the WSW has fed a lava flow down the W flank. A group of maars is located below the N and W flanks. The first observed and recorded eruption was a small explosion from the summit crater in 1911. Eruptive activity began again in December 1998, producing a lava dome that eventually covered much of the floor of the inner summit crater along with ongoing explosive ash emissions. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGz76aFBg$> ; Badan Nacional Penanggulangan Bencana (BNPB) http://www.bnpb.go.id/ <https://urldefense.com/v3/__http://www.bnpb.go.id/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lEnyaKd3w$> Kanlaon | Philippines | 10.4096°N, 123.13°E | Summit elev. 2422 m The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing eruptive activity at Kanlaon during 28 January-3 February. The seismic network recorded 5-16 daily volcanic earthquakes that, during 30 January-3 February, included 2-7 periods of volcanic tremor lasting two minutes to two hours and five minutes; volcanic tremor was not detected during 28-29 January. Average daily sulfur dioxide emissions ranged from 1,691 to 4,975 tonnes per day. Gas-and-steam emissions and those occasionally containing ash rose as high as 400 m above the summit and drifted NW, W, and SW. Weather clouds prevented views on 29 January. The eruption continued to impact residents. The National Disaster Risk Reduction and Management Council (NDRRMC) report issued at 0800 on 2 February stated that 9,834 people (3,107 families) were spread across 23 evacuation centers and another 8,388 people (2,662 families) were staying elsewhere. The Alert Level remained at 3 (on a scale of 0-5); the public was warned to stay 6 km away from the summit and pilots were warned not to fly close to the volcano. Geologic Summary. Kanlaon volcano (also spelled Canlaon) forms the highest point on the Philippine island of Negros. The massive andesitic stratovolcano is covered with fissure-controlled pyroclastic cones and craters, many of which are filled by lakes. The largest debris avalanche known in the Philippines traveled 33 km SW from Kanlaon. The summit contains a 2-km-wide, elongated northern caldera with a crater lake and a smaller but higher active vent, Lugud crater, to the south. Eruptions recorded since 1866 have typically consisted of phreatic explosions of small-to-moderate size that produce minor local ashfall. Sources: Philippine Institute of Volcanology and Seismology (PHIVOLCS) http://www.phivolcs.dost.gov.ph/ <https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lFRZbtnpg$> ; The National Disaster Risk Reduction and Management Council (NDRRMC) http://www.ndrrmc.gov.ph/ <https://urldefense.com/v3/__http://www.ndrrmc.gov.ph/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lHtRsB4FQ$> Karymsky | Russia | 54.049°N, 159.443°E | Summit elev. 1513 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported moderate levels of activity at Karymsky during 16-23 January. A weak thermal anomaly over the volcano was identified in satellite images. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGE1L6bKg$> Lewotobi | Indonesia | 8.542°S, 122.775°E | Summit elev. 1703 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity continued at Lewotobi Laki-laki during 29 January-4 February. An eruptive event was recorded at 1742 on 29 January though no emissions were visible due to weather clouds. Dense gray ash plumes on 2 and 4 February rose 400-700 m above the summit and drifted N and NE. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 5 km away from the center of Laki-laki and 6 km in a semicircle counterclockwise from the NE to the SW. 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGz76aFBg$> Lokon-Empung | Indonesia | 1.358°N, 124.792°E | Summit elev. 1580 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that seismicity at Lokon-Empung decreased during January. The number of shallow volcanic earthquakes gradually decreased from 102 daily events on 2 January, to 15 daily events on 15 January, to 1-5 daily events during 20-29 January. White emissions rose as high as 10 m above the summit. The Alert Level was lowered to 2 (on a scale of 1-4) at 0600 on 31 January and the public was warned to stay 1.5 km away from the crater. Geologic Summary. The Lokong-Empung volcanic complex, rising above the plain of Tondano in North Sulawesi, includes four peaks and an active crater. Lokon, the highest peak, has a flat craterless top. The morphologically younger Empung cone 2 km NE has a 400-m-wide, 150-m-deep crater that erupted last in the 18th century. A ridge extending 3 km WNW from Lokon includes the Tatawiran and Tetempangan peaks. All eruptions since 1829 have originated from Tompaluan, a 150 x 250 m crater in the saddle between Lokon and Empung. These eruptions have primarily produced small-to-moderate ash plumes that sometimes damaged croplands and houses, but lava-dome growth and pyroclastic flows have also occurred. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGz76aFBg$> Merapi | Indonesia | 7.54°S, 110.446°E | Summit elev. 2910 m The Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) reported that the eruption at Merapi (on Java) continued during 24-30 January. Seismicity was less intense than the previous week. The SW lava dome produced 57 lava avalanches that traveled as far as 1.8 km SW down the Bebeng drainage, 18 that traveled as far as 1.8 km SW down the Krasak drainage, and 31 that traveled as far as 2 km SW down the Sat/Putih drainage. Morphological changes at the SW dome were caused by continuing effusion and collapses of material. No significant morphological changes at the summit dome were visible. 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lE00bLqiA$> Popocatepetl | Mexico | 19.023°N, 98.622°W | Summit elev. 5393 m The Centro Nacional de Prevención de Desastres (CENAPRED) reported that eruptive activity continued at Popocatépetl during 28 January-4 February. The seismic network recorded 41-170 long-period events per day that were accompanied by steam-and-gas emissions sometimes containing minor amounts of ash. The seismic network also recorded daily tremor, sometimes characterized as very-low amplitude, with periods lasting 14 minutes to as long as four hours and 24 minutes. During 30-31 January a period of emissions lasted 170 min based on seismic data. One volcano-tectonic per day was detected during 31 January-4 February. According to the Washington VAAC ash plumes were visible in webcam and satellite images during 31 January-4 February rising 5.8-7 km (19,000-23,000 ft) a.s.l. (as high as 1.6 km above the summit) and drifting N 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGos_EMwg$> ; 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGQV090Bg$> Semeru | Indonesia | 8.108°S, 112.922°E | Summit elev. 3657 m The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity continued at Semeru during 29 January-4 February with daily eruptive events recorded by the seismic network. Gray or white-and-gray ash plumes rose 100-1,000 m above the summit and drifted N, NE, E, and SE. The Alert Level remained at 2 (the second lowest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards. Geologic Summary. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGz76aFBg$> Sheveluch | Russia | 56.653°N, 161.36°E | Summit elev. 3283 m The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that lava extrusion may have continued at Sheveluchâ??s â??300 years of RASâ?? dome on the SW flank of Old Sheveluch and at the Young Sheveluch dome during 16-23 January. Daily thermal anomalies over the domes were identified in satellite images. Gas-and-steam plumes with some ash drifted 60 km NE during 20-21 January and plumes of resuspended ash drifted 300 km SE during 21-23 January. 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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lGE1L6bKg$> 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 27 January-2 February. Webcam images showed Strombolian activity at four vents in Area N within the upper part of the Sciara del Fuoco and from two vents in Area C-S (South-Central Crater) on the crater terrace. The vents in Area N continued to produce low- to medium-intensity explosions at a rate of 8-9 events per hour, ejecting lapilli and bombs less than 150 m above the vents. Spattering continued and was sometimes intense, especially on 27 January and 2 February. Explosions at the vents in Area C-S ejected tephra more than 150 m above the vent at a rate of 2-4 events per hour. 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. Sources: Sezione di Catania - Osservatorio Etneo (INGV) http://www.ct.ingv.it/ <https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lFrStAc6A$> ; Dipartimento della Protezione Civile https://www.protezionecivile.gov.it/it/ <https://urldefense.com/v3/__https://www.protezionecivile.gov.it/it/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lEqeDq1Dg$> Suwanosejima | Japan | 29.638°N, 129.714°E | Summit elev. 796 m The Japan Meteorological Agency (JMA) reported that eruptive activity at Suwanosejima's Ontake Crater continued during 27 January-3 February. Incandescence was observed nightly in webcam images. An explosion was recorded at 0456 on 29 January though emission characteristics were unknown. Explosions at 0737 and 1740 on 2 February generated ash plumes that rose 400 m above the crater rim and drifted SE and 1 km above the crater rim and drifted S, respectively. Large blocks were ejected 400 m from the crater. Tremor accompanied the eruption events. The Alert Level remained at 2 (the second level on a five-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!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lH7MdAzHQ$> Ubinas | Peru | 16.345°S, 70.8972°W | Summit elev. 5608 m The Instituto GeofÃsico del Perú (IGP) reported that a lahar descended the Volcánmayo drainage on the SE flank of Ubinas at 1722 on 31 January. The public was warned to stay away from the drainage and to avoid driving on the Querapi-Ubinas-Huarina highway. The Alert Level remained at Yellow (the second level on a four-color scale) and the public was warned to stay 2 km away from the crater. Geologic Summary. The truncated appearance of Ubinas, Perú's most active volcano, is a result of a 1.4-km-wide crater at the summit. It is the northernmost of three young volcanoes located along a regional structural lineament about 50 km behind the main volcanic front. The growth and destruction of Ubinas I was followed by construction of Ubinas II beginning in the mid-Pleistocene. The upper slopes of the andesitic-to-rhyolitic Ubinas II stratovolcano are composed primarily of andesitic and trachyandesitic lava flows and steepen to nearly 45°. The steep-walled, 150-m-deep summit crater contains an ash cone with a 500-m-wide funnel-shaped vent that is 200 m deep. Debris-avalanche deposits from the collapse of the SE flank about 3,700 years ago extend 10 km from the volcano. Widespread Plinian pumice-fall deposits include one from about 1,000 years ago. Holocene lava flows are visible on the flanks, but activity documented since the 16th century has consisted of intermittent minor-to-moderate explosive eruptions. Source: Instituto GeofÃsico del Perú (IGP) http://www.igp.gob.pe/ <https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lEx4oj85g$> Yasur | Vanuatu | 19.532°S, 169.447°E | Summit elev. 361 m On 30 January the Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a level of â??major unrest,â?? as defined by the Alert Level 2 status (on a scale of 0-5). Satellite and webcam images indicated that explosions continued, producing emissions of gas, steam, and/or ash. Gas emissions were identified in satellite images and seismic data confirmed continuing volcanic activity. The report warned that some of the explosions may eject material that falls in and around the crater. The public was reminded to not enter the restricted area within 600 m around the boundaries of the Permanent Exclusion Zone, defined by Danger Zone A on the hazard map. Geologic Summary. Yasur has exhibited essentially continuous Strombolian and Vulcanian activity at least since Captain Cook observed ash eruptions in 1774. This style of activity may have continued for the past 800 years. Located at the SE tip of Tanna Island in Vanuatu, this pyroclastic cone has a nearly circular, 400-m-wide summit crater. The active cone is largely contained within the small Yenkahe caldera, and is the youngest of a group of Holocene volcanic centers constructed over the down-dropped NE flank of the Pleistocene Tukosmeru volcano. The Yenkahe horst is located within the Siwi ring fracture, a 4-km-wide open feature associated with eruption of the andesitic Siwi pyroclastic sequence. Active tectonism along the Yenkahe horst accompanying eruptions has raised Port Resolution harbor more than 20 m during the past century. Source: Vanuatu Meteorology and Geohazards Department (VMGD) http://www.geohazards.gov.vu/ <https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!dcJcInWzfMgO2c0mG7YaDxzVr6thSY5Etgil168-Uh0jzCbtyWzeeDhTmP1ufuQydR8YiIOvV19MVpZo6lHa3CchCg$> 3-3-3-3-3-3-3-3-3-3-3-3-3 ============================================================== Volcano Listserv is a collaborative venture among Arizona State University (ASU), Portland State University (PSU), the Global Volcanism Program (GVP) of the Smithsonian Institution's National Museum of Natural History, and the International Association for Volcanology and Chemistry of the Earth's Interior (IAVCEI). 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