7-7-7-7-7-7-7-7-7-7-7-7-7-7 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 17-23 July 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHEhFf-CxQ$> New Activity/Unrest: Bezymianny, Central Kamchatka (Russia) | Etna, Sicily (Italy) | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaiian Islands (USA) | Mayon, Luzon (Philippines) | Sumisujima, Izu Islands | Whakaari/White Island, North Island (New Zealand) | Yellowstone, Eastern Snake River Plain Ongoing Activity: Aira, Kyushu (Japan) | Dukono, Halmahera | Ebeko, Paramushir Island (Russia) | Erta Ale, Ethiopia | Great Sitkin, Andreanof Islands (USA) | Home Reef, Tonga Ridge | Ibu, Halmahera | Lateiki, Tonga Ridge | Lewotobi, Flores Island | Marapi, Central Sumatra | Merapi, Central Java | Semeru, Eastern Java | Sheveluch, Central Kamchatka (Russia) | Suwanosejima, Ryukyu Islands (Japan) | Villarrica, Central Chile 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 | Central Kamchatka (Russia) | 55.972°N, 160.595°E | Summit elev. 2882 m KVERT reported that lava extrusion at Bezymianny significantly increased on 21 July, causing collapses of the E part of the lava dome and subsequent hot avalanches of material. Ash plumes from the collapses rose 2-3 km a.s.l. On 22 July the Aviation Color Code was raised to Orange (the third level on a four-color scale). Activity was sustained at least through 24 July, and by then ash plumes were drifting 70 km SW. Dates and times 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHGowtMuQg$> Etna | Sicily (Italy) | 37.748°N, 14.999°E | Summit elev. 3357 m INGV reported that activity at Etnaâ??s summit craters continued during 14-23 July. Explosive activity at both Voragine Crater and NE Crater began to slowly intensify at around 1500 on 14 July and ash emissions from both craters rapidly dispersed. Infrasound data showed increasing activity at NW Crater at around 1600. Strombolian activity at Voragine Crater persisted on 15 July, and that same day minor ash emissions from Voragine and NE craters were visible in webcam images. Volcanic tremor amplitude values fluctuated at average values for most of the day, then began to increase. Activity at Voragine was observed in infrasound data. Strombolian activity at Voragine slowly intensified beginning around 2100 and volcanic tremor amplitude reached very high levels, peaking at 2140. Activity continued to intensify, and lava fountaining began at 2154. Ash plumes reached about 6 km a.s.l., or about 2.6 km above the summit, and drifted SE. Ashfall was reported in areas downwind including Viagrande (16 km SSE) and Aci Castello (26 km SSE). Lava flowed over the NW rim of Bocca Nuova Crater and descended to about 3,000 m elevation. The average volcanic tremor amplitude remained at very high levels and peaked again at 0100 on 16 July. Infrasound data showed a decrease in the frequency of events. Lava fountaining decreased and had ceased by 0210 on 16 July, though Strombolian activity persisted until around 0500. Reddish ash plumes occasionally rose from NE Crater throughout the day. Strombolian activity at NE Crater began at around 2300 and ejected large bombs several tens of meters above the crater rim. The lava flow continued to be fed though at a low rate. INGV staff visited the summit area on 17 July and saw Strombolian activity in NE Crater; the activity was also visible in webcam images. The activity produced both fine and coarse material that was ejected tens of meters above the crater rim; the coarser material fell back inside the crater as well as onto the flanks. An explosion at NE Crater at 1956 produced an ash plume that rapidly dispersed. Strombolian activity at Voragine Crater was again visible in webcam images on 22 July, though weather clouds mostly obscured observations. Volcanic tremor amplitude was low, though gradually increasing, through the day; the amplitude reached a high level by 1745 and remained high. Infrasound data indicated activity in Voragine. The Strombolian activity intensified and was characterized as strong by 0300 on 23 July. Ash emissions rose about the summit, volcanic tremor amplitude increased to very high levels, and by 0508 lava fountaining was underway that resulted in overflows of the Bocca Nuova Crater W rim. Lava fountaining persisted and by 0830 fountains were rising several hundred meters above the crater rim. Ash plumes rose around 8 km a.s.l., or about 4.6 km above the summit, and drifted ESE, then SSE. Ashfall was reported in Rifugio Sapienza (5 km S), Piano Vetore (6 km SSW), C.da Milia, Nicolosi (15 km S), Tremestieri Etneo (20 km SSE), and Catania (29 km SSE). The lava fountaining gradually decreased and then ceased by 1015. The lava flow produced during the activity was small, though due to weather clouds the total length was undetermined. 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHF8j7TbqQ$> Karymsky | Eastern Kamchatka (Russia) | 54.049°N, 159.443°E | Summit elev. 1513 m KVERT reported moderate levels of activity at Karymsky during 11-18 July. A thermal anomaly over the volcano was identified in satellite images on 12, 15, and 18 July; weather clouds obscured views on the other days during the week. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted. Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHGowtMuQg$> Kilauea | Hawaiian Islands (USA) | 19.421°N, 155.287°W | Summit elev. 1222 m HVO reported that at about 0330 on 23 July increased earthquake activity and abrupt ground deformation around Kilaueaâ??s upper East Rift Zone likely indicated the movement of magma in the subsurface. The Volcano Alert Level was raised to Watch (the third level on a four-level scale) and the Aviation Color Code was raised to Orange (the third color on a four-color scale) at 0406. The seismicity was centered near Pauahi Crater. During 22-23 July there were about 357 earthquakes beneath the upper East Rift Zone mainly at depths of 0-4 km. Most of the events were smaller than M 2, though 13 of the earthquakes were larger with magnitudes of M 3-3.4. 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHXECvd6w$> Mayon | Luzon (Philippines) | 13.257°N, 123.685°E | Summit elev. 2462 m PHIVOLCS reported that 0-3 daily rockfalls and volcanic earthquakes at Mayon were detected by the seismic network during 16-22 July. Moderate levels of emissions drifted mainly NW, W, and SW and occasionally ENE. Faint crater incandescence was only visible using a telescope. A phreatic explosion occurred at 1816 on 18 July and lasted for 45 seconds based on seismic data. According to the Tokyo VAAC the plume rose 2.7 km (9,000 ft) a.s.l., or about 280 m above the summit, and drifted WNW. There were 11 rockfalls recorded during 18-19 July. The Alert Level remained at 1 (on a 0-5 scale); the public was reminded to stay out of the 6-km-radius Permanent Danger Zone (PDZ) and pilots were advised to avoid flying close to the summit. Geologic Summary. Symmetrical Mayon, which rises above the Albay Gulf NW of Legazpi City, is the most active volcano of the Philippines. The steep upper slopes are capped by a small summit crater. Recorded eruptions since 1616 CE range from Strombolian to basaltic Plinian, with cyclical activity beginning with basaltic eruptions, followed by longer periods of andesitic lava flows. Eruptions occur predominately from the central conduit and have also produced lava flows that travel far down the flanks. Pyroclastic density currents and mudflows have commonly swept down many of the approximately 40 ravines that radiate from the summit and have often damaged populated lowland areas. A violent eruption in 1814 killed more than 1,200 people and devastated several towns. Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS) http://www.phivolcs.dost.gov.ph/ <https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHFsyoPG_A$> Sumisujima | Izu Islands | 31.44°N, 140.051°E | Summit elev. 136 m The Japan Coast Guard reported that an area of discolored water, brown to yellow-green in color, was visible about 300 m E of the E coast of Sumisujima on 18 July. The report noted that areas of discolored water had occasionally been seen in the vicinity of the island since 2017, though usually characterized as pale blue to white and smaller in size. Sailors were warned to exercise caution in the area. Geologic Summary. Sumisujima (also known as Smith Rocks) is a steep-sided basaltic pinnacle that forms part of the outer southern flank of a 8-9 km wide submarine caldera that truncates a 20-km-wide seamount. The caldera was formed between about 60,000 and 30,000 years ago. The Shirane dacitic central cone, 3 km wide and 800 m high, rises to within 8 m of the ocean surface in the eastern side of the caldera, whose 600-700 m walls and outer flanks expose basaltic, andesitic, and rhyolitic rocks. Two large submarine cones, Sumisu Knolls No. 1 and 2, lie west of the caldera. Submarine eruptions have been reported from a number of locations near Sumisujima, the last of which occurred in 1916. Water discoloration has frequently been observed since the 1970's. In October 1992 a 6-km-long zone of discolored water was seen extending from the shallow Shirane rock mass near the eastern rim of the caldera, which rises to within 7 m of the ocean surface and is the youngest feature of the volcanic complex. Source: Japan Coast Guard http://www.kaiho.mlit.go.jp/index.html <https://urldefense.com/v3/__http://www.kaiho.mlit.go.jp/index.html__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHokV9-qg$> Whakaari/White Island | North Island (New Zealand) | 37.52°S, 177.18°E | Summit elev. 294 m GeoNet reported decreasing activity at Whakaari/White Island and confirmed recent activity during overflight observations. A vent on the crater floor increased in diameter by about 20 m sometime during 3-7 July, likely coinciding during a time when larger-than-normal plumes were seen by coastal observers and in webcam images. Impact craters from material ejected during minor explosive activity were scattered as far as 250 m from the active vent based on photographs taken during gas monitoring and observation overflights. A thin ashfall deposit extended across parts of the crater floor. A gas-and-steam plume was continuously emitted from the vent for a period of time on 10 July. During a 12 July overflight the plume contained intermittent and minor amounts of ash likely resulting from erosion inside the vent due to vigorous degassing. During an 18 July overflight GeoNet confirmed that activity had decreased. Gas-and-steam plumes continued to rise from the vent, though with less vigor, and the crater lake had completely dried up. Volcanic gas emissions were decreasing. Steam-and-gas plumes persisted at other vents. The Volcanic Alert Level remained at 2 (on a scale of 0-5) and the Aviation Color Code remained at Yellow (the second 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHEFvbZe1g$> Yellowstone | Eastern Snake River Plain | 44.43°N, 110.67°W | Summit elev. 2805 m The Yellowstone Volcano Observatory (YVO) reported that at around 1000 on 23 July a small hydrothermal explosion occurred in Yellowstoneâ??s Biscuit Basin thermal area, located about 3.5 km NW of Old Faithful. The explosion likely originated near Black Diamond Pool and was recorded by visitors that were on the nearby boardwalk. Ejecta from the explosion damaged the boardwalk; no injuries were reported. Biscuit Basin, including the parking lot and boardwalks, were temporary closed for visitor safety. YVO noted that the explosion did not reflect activity within volcanic system, which remained at normal background levels of activity, and was not caused by magma rising towards the surface. Hydrothermal explosions are relatively common in Yellowstone. The Volcano Alert Level remained at Normal (the lowest level on a four-level scale) and the Aviation Color Code remained at Green (the lowest color on a four-color scale). Geologic Summary. The Yellowstone Plateau volcanic field developed through three volcanic cycles spanning two million years that included some of the world's largest known eruptions. Eruption of the over 2,450 km3 Huckleberry Ridge Tuff about 2.1 million years ago created the more than 75-km-long Island Park caldera. The second cycle concluded with the eruption of the Mesa Falls Tuff around 1.3 million years ago, forming the 16-km-wide Henrys Fork caldera at the western end of the first caldera. Activity subsequently shifted to the present Yellowstone Plateau and culminated 640,000 years ago with the eruption of the over 1,000 km3 Lava Creek Tuff and the formation of the present 45 x 85 km caldera. Resurgent doming subsequently occurred at both the NE and SW sides of the caldera and voluminous (1000 km3) intracaldera rhyolitic lava flows were erupted between 150,000 and 70,000 years ago. No magmatic eruptions have occurred since the late Pleistocene, but large hydrothermal events took place near Yellowstone Lake during the Holocene. Yellowstone is presently the site of one of the world's largest hydrothermal systems, including Earth's largest concentration of geysers. Source: Yellowstone Volcano Observatory (YVO) https://www.usgs.gov/observatories/yvo <https://urldefense.com/v3/__https://www.usgs.gov/observatories/yvo__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHGmL8Ab1Q$> Ongoing Activity Aira | Kyushu (Japan) | 31.5772°N, 130.6589°E | Summit elev. 1117 m JMA reported ongoing eruptive activity at Minamidake Crater (Aira Calderaâ??s Sakurajima volcano) during 15-22 July. Nighttime crater incandescence was sometimes visible and very small eruptive events were occasionally recorded. An explosion at 1358 on 20 July produced an ash plume that rose 3.7 km above the crater rim and drifted NE, and ejected large blocks 600-900 m from the vent. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 1 km away from both craters. Geologic Summary. The Aira caldera in the northern half of Kagoshima Bay contains the post-caldera Sakurajima volcano, one of Japan's most active. Eruption of the voluminous Ito pyroclastic flow accompanied formation of the 17 x 23 km caldera about 22,000 years ago. The smaller Wakamiko caldera was formed during the early Holocene in the NE corner of the caldera, along with several post-caldera cones. The construction of Sakurajima began about 13,000 years ago on the southern rim and built an island that was joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kitadake summit cone ended about 4,850 years ago, after which eruptions took place at Minamidake. Frequent eruptions since the 8th century have deposited ash on the city of Kagoshima, located across Kagoshima Bay only 8 km from the summit. The largest recorded eruption took place during 1471-76. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHxHobvrA$> Dukono | Halmahera | 1.6992°N, 127.8783°E | Summit elev. 1273 m PVMBG reported that the eruption at Dukono was ongoing during 17-23 July. Gray-and-white ash plumes rose 100-400 m above the summit and drifted E on 17 July. Emissions were not observed during 18-21 July, and dense white plumes rose 200-600 m and drifted NW on 22 July. 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHGNU2QvQ$> Ebeko | Paramushir Island (Russia) | 50.686°N, 156.014°E | Summit elev. 1103 m KVERT reported that moderate explosive activity was ongoing at Ebeko during 11-18 July. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E), explosions during 15-18 July generated ash plumes that rose as high as 3 km (10,000 ft) a.s.l. and drifted E, NE, and S. Thermal anomalies were identified in satellite images on 18 July; on other days either no activity was observed or weather conditions prevented views. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are UTC; specific events are in local time where noted. Geologic Summary. The flat-topped summit of the central cone of Ebeko volcano, one of the most active in the Kuril Islands, occupies the northern end of Paramushir Island. Three summit craters located along a SSW-NNE line form Ebeko volcano proper, at the northern end of a complex of five volcanic cones. Blocky lava flows extend west from Ebeko and SE from the neighboring Nezametnyi cone. The eastern part of the southern crater contains strong solfataras and a large boiling spring. The central crater is filled by a lake about 20 m deep whose shores are lined with steaming solfataras; the northern crater lies across a narrow, low barrier from the central crater and contains a small, cold crescentic lake. Historical activity, recorded since the late-18th century, has been restricted to small-to-moderate explosive eruptions from the summit craters. Intense fumarolic activity occurs in the summit craters, on the outer flanks of the cone, and in lateral explosion craters. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHGowtMuQg$> Erta Ale | Ethiopia | 13.601°N, 40.666°E | Summit elev. 585 m Thermal anomalies in satellite images of Erta Ale on 11, 16, and 21 July suggested that lava flows from the S pit crater traveled about 870 m SSE. Geologic Summary. The Erta Ale basaltic shield volcano in Ethiopia has a 50-km-wide edifice that rises more than 600 m from below sea level in the Danakil depression. The volcano includes a 0.7 x 1.6 km summit crater hosting steep-sided pit craters. Another larger 1.8 x 3.1 km wide depression elongated parallel to the trend of the Erta Ale range is located SE of the summit and is bounded by curvilinear fault scarps on the SE side. Basaltic lava flows from these fissures have poured into the caldera and locally overflowed its rim. The summit caldera usually also holds at least one long-term lava lake that has been active since at least 1967, and possibly since 1906. Recent fissure eruptions have occurred on the N flank. Source: Copernicus https://www.copernicus.eu/en <https://urldefense.com/v3/__https://www.copernicus.eu/en__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHPQvkjKg$> Great Sitkin | Andreanof Islands (USA) | 52.076°N, 176.13°W | Summit elev. 1740 m AVO reported that slow lava effusion in Great Sitkinâ??s summit crater was last confirmed in an 18 July radar image and that same day elevated surface temperatures were detected in satellite images; effusion likely continued during 19-23 July. The lava flow expanded E and S, overtopping older lava flows emplaced during 2022-2024. Lava blocks sometimes detached from the flow and descended the flow margins; the tumbling blocks were seismically detected. Small daily earthquakes beneath the volcano were recorded during 16-23 July. Weather conditions often obscured satellite and webcam views. 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHFszmrLKQ$> Home Reef | Tonga Ridge | 18.992°S, 174.775°W | Summit elev. -10 m A 20 July satellite image of Home Reef showed a N-S-elongated thermal anomaly over the vent area. Geologic Summary. Home Reef, a submarine volcano midway between Metis Shoal and Late Island in the central Tonga islands, was first reported active in the mid-19th century, when an ephemeral island formed. An eruption in 1984 produced a 12-km-high eruption plume, large amounts of floating pumice, and an ephemeral 500 x 1,500 m island, with cliffs 30-50 m high that enclosed a water-filled crater. In 2006 an island-forming eruption produced widespread dacitic pumice rafts that drifted as far as Australia. Another island was built during a September-October 2022 eruption. Source: Copernicus https://www.copernicus.eu/en <https://urldefense.com/v3/__https://www.copernicus.eu/en__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHPQvkjKg$> Ibu | Halmahera | 1.488°N, 127.63°E | Summit elev. 1325 m PVMBG reported that activity at Ibu continued during 17-23 July. Daily white-and-gray or white, gray, and black ash plumes rose 100-1,200 m above the summit and drifted in multiple directions. The Alert Level remained at 3 (the second highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 5 km away from the N crater wall opening. Geologic Summary. The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, has contained several small crater lakes. The 1.2-km-wide outer crater is breached on the N, creating a steep-walled valley. A large cone grew ENE of the summit, and a smaller one to the WSW has fed a lava flow down the W flank. A group of maars is located below the N and W flanks. The first observed and recorded eruption was a small explosion from the summit crater in 1911. Eruptive activity began again in December 1998, producing a lava dome that eventually covered much of the floor of the inner summit crater along with ongoing explosive ash emissions. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHGNU2QvQ$> Lateiki | Tonga Ridge | 19.18°S, 174.87°W | Summit elev. 43 m Satellite data showed an area of discolored water in the vicinity of the submarine Lateiki volcano drifting about 1.2 km SW on 20 July. Weather clouds obscured part of the area. Geologic Summary. Lateiki, previously known as Metis Shoal, is a submarine volcano midway between the islands of Kao and Late that has produced a series of ephemeral islands since the first confirmed activity in the mid-19th century. An island, perhaps not in eruption, was reported in 1781 and subsequently eroded away. During periods of inactivity following 20th-century eruptions, waves have been observed to break on rocky reefs or sandy banks with depths of 10 m or less. Dacitic tuff cones formed during the eruptions in 1967 and 1979 were soon eroded beneath the ocean surface. An eruption in 1995 produced an island with a diameter of 280 m and a height of 43 m following growth of a lava dome above the surface. Source: Copernicus https://www.copernicus.eu/en <https://urldefense.com/v3/__https://www.copernicus.eu/en__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHPQvkjKg$> Lewotobi | Flores Island | 8.542°S, 122.775°E | Summit elev. 1703 m PVMBG reported that eruptive activity at Lewotobiâ??s Laki-laki volcano continued during 3-9 July. Multiple daily gray or white-and-gray ash plumes that were sometimes dense rose 50-1,500 m above the summit and drifted SW, W, and NW. According to a news article, several villages were impacted by ashfall on 22 July, including Wolorona (5 km WNW), Klatanlou (4 km NW), Goliriang, Hokeng (3 km WNW), Pululera (6 km NW), Padang Pasir (5 km NW), Boru (8 km WNW), Wotupudor, and Kumaebang. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3-km radius around both Laki-laki and Perempuan craters, 4 km to the NNW and SSE of Laki-laki. Geologic Summary. The Lewotobi edifice in eastern Flores Island is composed of the two adjacent Lewotobi Laki-laki and Lewotobi Perempuan stratovolcanoes (the "husband and wife"). Their summits are less than 2 km apart along a NW-SE line. The conical Laki-laki to the NW has been frequently active during the 19th and 20th centuries, while the taller and broader Perempuan has had observed eruptions in 1921 and 1935. Small lava domes have grown during the 20th century in both of the summit craters, which are open to the north. A prominent cone, Iliwokar, occurs on the E flank of Perampuan. Sources: Antara News https://www.antaranews.com/berita/4209402/potensi-erupsi-gunung-lewotobi-laki-laki-masih-tinggi <https://urldefense.com/v3/__https://www.antaranews.com/berita/4209402/potensi-erupsi-gunung-lewotobi-laki-laki-masih-tinggi__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHQaV9nvg$> ; 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHGNU2QvQ$> Marapi | Central Sumatra | 0.38°S, 100.474°E | Summit elev. 2885 m PVMBG reported that eruptive activity at Marapi (on Sumatra) was ongoing during 17-23 July. White gas-and-steam plumes rose 100-250 m above the summit and drifted NE, E, and S during 17-18 and 20 July. Gray ash plumes rose 150 m above the summit and drifted NE and E on 19 July. Emissions were not observed on the other days. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay 3 km away from the active crater. Geologic Summary. Gunung Marapi, not to be confused with the better-known Merapi volcano on Java, is Sumatra's most active volcano. This massive complex stratovolcano rises 2,000 m above the Bukittinggi Plain in the Padang Highlands. A broad summit contains multiple partially overlapping summit craters constructed within the small 1.4-km-wide Bancah caldera. The summit craters are located along an ENE-WSW line, with volcanism migrating to the west. More than 50 eruptions, typically consisting of small-to-moderate explosive activity, have been recorded since the end of the 18th century; no lava flows outside the summit craters have been reported in historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHGNU2QvQ$> Merapi | Central Java | 7.54°S, 110.446°E | Summit elev. 2910 m BPPTKG reported that the eruption at Merapi (on Java) continued during 12-18 July. Earthquakes were less intense compared to the previous week. The SW lava dome produced 177 lava avalanches that traveled as far as 2 km down the upper part of the Bebeng drainage on the SW flank and 1.1 km down the Bedog drainage on the SSW flank. Morphological changes to the SW lava dome were due to continuing effusion and collapses of material. The volume of the SW dome was an estimated 2,516,600 cubic meters and the dome in the main crater was stable at an estimated 2,360,700 cubic meters based on an 18 July drone survey and webcam images. The highest temperature of the SW dome was around 245 degrees Celsius, higher than the previous measurement. 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHGDXOeSPA$> Semeru | Eastern Java | 8.108°S, 112.922°E | Summit elev. 3657 m PVMBG reported that eruptive activity continued at Semeru during 17-23 July. White-and-gray ash plumes that were sometimes dense rose 400-1,000 m above the summit and drifted mainly S and SW and sometimes N and NE. Daily eruptive events, sometimes several per day, were recorded by the seismic network, though plumes were not always visually confirmed. The Alert Level remained at 2 (the second lowest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards. Geologic Summary. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) http://vsi.esdm.go.id/ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHGNU2QvQ$> Sheveluch | Central Kamchatka (Russia) | 56.653°N, 161.36°E | Summit elev. 3283 m KVERT reported that thermal anomalies over both the â??300 years of RASâ?? dome and the older lava dome at Sheveluch were identified in satellite images during 12-15 and 18 July. Weather conditions prevented views on the other days during 12-19 July. 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. 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!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHGowtMuQg$> Suwanosejima | Ryukyu Islands (Japan) | 29.638°N, 129.714°E | Summit elev. 796 m JMA reported that eruptive activity at Suwanosejima's Ontake Crater continued during 15-22 July and produced volcanic plumes that rose as high as 1.2 km above the crater rim and drifted N and NW. Large blocks were ejected as far as 300 m from the vent, though no explosions were recorded. Crater incandescence was observed nightly in webcam images. The Alert Level remained at 2 (on a 5-level scale) and the public was warned to stay at least 1.5 km away from the crater. Geologic Summary. The 8-km-long island of Suwanosejima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two active summit craters. The summit is truncated by a large breached crater extending to the sea on the E flank that was formed by edifice collapse. One of Japan's most frequently active volcanoes, it was in a state of intermittent Strombolian activity from Otake, the NE summit crater, between 1949 and 1996, after which periods of inactivity lengthened. The largest recorded eruption took place in 1813-14, when thick scoria deposits covered residential areas, and the SW crater produced two lava flows that reached the western coast. At the end of the eruption the summit of Otake collapsed, forming a large debris avalanche and creating an open collapse scarp extending to the eastern coast. The island remained uninhabited for about 70 years after the 1813-1814 eruption. Lava flows reached the eastern coast of the island in 1884. Only about 50 people live on the island. Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHHxHobvrA$> Villarrica | Central Chile | 39.42°S, 71.93°W | Summit elev. 2847 m After field observations and analysis of data, Servicio Nacional de GeologÃa y MinerÃa (SERNAGEOMIN) reduced the exclusion zone around Villarrica to 1.5 km on 19 July. SENAPRED maintained the Alert Level at Yellow (the middle level on a three-color scale) for the communities of Villarrica, Pucón (16 km N), Curarrehue, and Panguipulli. Two ash emissions were recorded at 1346 and 1349 on 21 July and drifted NE. The second ash plume rose 320 m above the crater rim and was associated with a long-period earthquake. Another ash emission event at 1438 was also associated with a long-period earthquake; the plume rose 780 m above the crater rim and drifted NE. Geologic Summary. The glacier-covered Villarrica stratovolcano, in the northern Lakes District of central Chile, is ~15 km south of the city of Pucon. A 2-km-wide caldera that formed about 3,500 years ago is located at the base of the presently active, dominantly basaltic to basaltic-andesite cone at the NW margin of a 6-km-wide Pleistocene caldera. More than 30 scoria cones and fissure vents are present on the flanks. Plinian eruptions and pyroclastic flows that have extended up to 20 km from the volcano were produced during the Holocene. Lava flows up to 18 km long have issued from summit and flank vents. Eruptions documented since 1558 CE have consisted largely of mild-to-moderate explosive activity with occasional lava effusion. Glaciers cover 40 km2 of the volcano, and lahars have damaged towns on its flanks. Sources: Servicio Nacional de GeologÃa y MinerÃa (SERNAGEOMIN) http://www.sernageomin.cl/ <https://urldefense.com/v3/__http://www.sernageomin.cl/__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHH_gk2sVA$> ; Sistema y Servicio Nacional de Prevención y Repuesta Ante Desastres (SENAPRED) https://senapred.cl/ <https://urldefense.com/v3/__https://senapred.cl/__;!!IKRxdwAv5BmarQ!boDnc0q9sWYzPxNvvcVb5RrkoRHxFUXhv8HyR_0T8OE9fe8oI0vU54WoubtkseTOxcrTqDeBaej1dJF2lHGf5WvrHQ$> 7-7-7-7-7-7-7-7-7-7-7-7-7-7 ============================================================== 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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