1-1-1-1-1-1-1-1-1-1-1-1-1-1 From: "Kuhn, Sally" <KUHNS@xxxxxx> Smithsonian / USGS Weekly Volcanic Activity Report 4-10 August 2021 Sally Kuhn Sennert - Weekly Report Editor (kuhns@xxxxxx) URL: https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KvilGHbw$ <https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-j7VTWU0$> New Activity/Unrest: Chirinkotan, Kuril Islands (Russia) | Great Sitkin, Andreanof Islands (USA) | Nyiragongo, DR Congo | Pacaya, Guatemala | Pagan, Mariana Islands (USA) | Pavlof, United States | Semisopochnoi, Aleutian Islands (USA) | Suwanosejima, Ryukyu Islands (Japan) | Tengger Caldera, Eastern Java (Indonesia) | Whakaari/White Island, North Island (New Zealand) Ongoing Activity: Aira, Kyushu (Japan) | Asamayama, Honshu (Japan) | Copahue, Central Chile-Argentina border | Dukono, Halmahera (Indonesia) | Ebeko, Paramushir Island (Russia) | Etna, Sicily (Italy) | Fuego, Guatemala | Karymsky, Eastern Kamchatka (Russia) | Lewotolok, Lembata Island (Indonesia) | Merapi, Central Java (Indonesia) | Popocatepetl, Mexico | Raung, Eastern Java (Indonesia) | Santa Maria, Guatemala | Semeru, Eastern Java (Indonesia) | Sheveluch, Central Kamchatka (Russia) | Sinabung, Indonesia 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 Chirinkotan | Kuril Islands (Russia) | 48.98°N, 153.48°E | Summit elev. 724 m According to KVERT an explosion at Chirinkotan at 1745 on 8 August produced an ash plume that rose 2-2.7 km (6,600-9,000 ft) a.s.l. and drifted 86 km WSW and SW. KVERT raised the Aviation Color Code to Orange (the second highest level on a four-color scale). KVERT, SVERT, and the VAAC reported continuing ash-producing events through 10 August. Notably at 1915 on 9 August an ash cloud, 10 x 13 km in size, possibly rose as high as 3.7 km (12,000 ft) a.s.l. and drifted 26-30 km SSE and S. An explosive event at 0855 on 10 August produced an ash plume 11 x 14 km in size that rose 2-2.5 km (6,600-8,200 ft) a.s.l. and drifted 70 km W. Geologic Summary. The small, mostly unvegetated 3-km-wide island of Chirinkotan occupies the far end of an E-W volcanic chain that extends nearly 50 km W of the central part of the main Kuril Islands arc. It is the emergent summit of a volcano that rises 3000 m from the floor of the Kuril Basin. A small 1-km-wide caldera about 300-400 m deep is open to the SW. Lava flows from a cone within the breached crater reached the shore of the island. Historical eruptions have been recorded since the 18th century. Lava flows were observed by the English fur trader Captain Snow in the 1880s. Sources: Kamchatkan Volcanic Eruption Response Team (KVERT) https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KZvRaCns$ <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-baRGmQM$> ; Sakhalin Volcanic Eruption Response Team (SVERT) https://urldefense.com/v3/__http://www.imgg.ru/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KcJs2dHI$ <https://urldefense.com/v3/__http://www.imgg.ru/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-xcelZJs$> ; Tokyo Volcanic Ash Advisory Center (VAAC) https://urldefense.com/v3/__http://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KGnjOEFk$ <https://urldefense.com/v3/__http://ds.data.jma.go.jp/svd/vaac/data/vaac_list.html__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4--aJV4Y4$> Great Sitkin | Andreanof Islands (USA) | 52.076°N, 176.13°W | Summit elev. 1740 m AVO reported that unrest continued at Great Sitkin during 4-10 August with elevated seismicity, elevated surface temperatures, and explosions associated with a growing lava dome. Numerous earthquakes and small explosions were recorded on local infrasound and seismic stations during 4-5 August. During the morning of 5 August observers reported possible low-level lava fountaining from the active vent; the activity was also visible from Adak Island. Throughout the same day a volcanic plume comprised mostly of gas and steam (and possibly ash) was visible in webcam images rising to 3 km (10,000 ft) a.s.l. By 6 August the lava dome had grown to 250 m in diameter and had an approximate volume of about 1 million cubic meters. AVO noted that most of the crater was full of lava erupted in 1974 and that the current lava covered only 4-5 percent of the total summit crater area. Elevated surface temperatures were identified in satellite images during 6-10 August, though weather clouds mostly prevented satellite and webcam views. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively. Geologic Summary. The Great Sitkin volcano forms much of the northern side of Great Sitkin Island. A younger parasitic 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 ancestral volcano and produced a submarine debris avalanche. Deposits from this and an 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. Historical eruptions have been recorded since the late-19th century. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9K5evT6z8$ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-RMZbTuM$> Nyiragongo | DR Congo | 1.52°S, 29.25°E | Summit elev. 3470 m Goma Volcano Observatory (GVO) reported that a gas-and-ash plume rose from Nyiragongo at 1420 on 4 August. Geologic Summary. One of Africa's most notable volcanoes, Nyiragongo contained a lava lake in its deep summit crater that was active for half a century before draining catastrophically through its outer flanks in 1977. The steep slopes of a stratovolcano contrast to the low profile of its neighboring shield volcano, Nyamuragira. Benches in the steep-walled, 1.2-km-wide summit crater mark levels of former lava lakes, which have been observed since the late-19th century. Two older stratovolcanoes, Baruta and Shaheru, are partially overlapped by Nyiragongo on the north and south. About 100 parasitic cones are located primarily along radial fissures south of Shaheru, east of the summit, and along a NE-SW zone extending as far as Lake Kivu. Many cones are buried by voluminous lava flows that extend long distances down the flanks, which is characterized by the eruption of foiditic rocks. The extremely fluid 1977 lava flows caused many fatalities, as did lava flows that inundated portions of the major city of Goma in January 2002. Source: Observatoire Volcanologique de Goma (OVG) Pacaya | Guatemala | 14.382°N, 90.601°W | Summit elev. 2569 m INSIVUMEH reported that explosions at Pacaya were recorded at 0905, 1340, and 1421 on 4 August, a departure from the low levels of activity observed during the previous four months. The explosions produced ash plumes that rose about 1 km above the summit and drifted 12 km N, causing ashfall in MesÃas Altas, MesÃas Bajas, and Villa Canales. The report noted that the cinder cone in Mackenney Crater had been destroyed during the previous eruption phase and the crater was about 100 m deep. Cracks were seen around the crater indicating areas of instability at the summit. Steam-and-gas plumes rose as high as 1 km above the summit and drifted as far as 3 km in multiple directions during 5-10 August. No explosions were heard or visually observed, though the seismic network recorded weak explosion signals during 6-7 August. Geologic Summary. Eruptions from Pacaya, one of Guatemala's most active volcanoes, are frequently visible from Guatemala City, the nation's capital. This complex basaltic volcano was constructed just outside the southern topographic rim of the 14 x 16 km Pleistocene Amatitlán caldera. A cluster of dacitic lava domes occupies the southern caldera floor. The post-caldera Pacaya massif includes the ancestral Pacaya Viejo and Cerro Grande stratovolcanoes and the currently active Mackenney stratovolcano. Collapse of Pacaya Viejo between 600 and 1500 years ago produced a debris-avalanche deposit that extends 25 km onto the Pacific coastal plain and left an arcuate somma rim inside which the modern Pacaya volcano (Mackenney cone) grew. A subsidiary crater, Cerro Chino, was constructed on the NW somma rim and was last active in the 19th century. During the past several decades, activity has consisted of frequent strombolian eruptions with intermittent lava flow extrusion that has partially filled in the caldera moat and armored the flanks of Mackenney cone, punctuated by occasional larger explosive eruptions that partially destroy the summit of the growing young stratovolcano. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9K2WwfLJw$ <https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-HCANeuM$> Pagan | Mariana Islands (USA) | 18.13°N, 145.8°E | Summit elev. 570 m Felt earthquakes and minor emissions from Pagan were observed on 29 July. No additional activity had been reported by 6 August; the Aviation Color Code and the Volcano Alert Level remained at Yellow/Advisory, respectively. Seismic, infrasound, and web camera data from the volcano remained unavailable; no activity was observed in satellite images. Geologic Summary. Pagan Island, the largest and one of the most active of the Mariana Islands volcanoes, consists of two stratovolcanoes connected by a narrow isthmus. Both North and South Pagan stratovolcanoes were constructed within calderas, 7 and 4 km in diameter, respectively. North Pagan at the NE end of the island rises above the flat floor of the northern caldera, which may have formed less than 1,000 years ago. South Pagan is a stratovolcano with an elongated summit containing four distinct craters. Almost all of the recorded eruptions, which date back to the 17th century, have originated from North Pagan. The largest eruption during historical time took place in 1981 and prompted the evacuation of the sparsely populated island. Source: US Geological Survey https://urldefense.com/v3/__https://www.usgs.gov/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KGL7ThCo$ <https://urldefense.com/v3/__https://www.usgs.gov/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-WvxfIfc$> Pavlof | United States | 55.417°N, 161.894°W | Summit elev. 2493 m Intermittent bursts of ash from the summit of Pavlof were visible in webcam views on 5 August, prompting AVO to raise the Volcano Alert Level and Aviation Color Code to Watch and Orange, respectively. The bursts formed diffuse plumes that rose just above the summit and drifted almost 10 km SE before dissipating. Minor daily ash emissions continued to be observed in webcam images during 5-9 August. The seismic network recorded elevated seismicity (tremor) and small explosions. Several small explosions were recorded during 8-9 August though weather clouds prevented satellite and webcam views. Geologic Summary. The most active volcano of the Aleutian arc, Pavlof is a 2519-m-high Holocene stratovolcano that was constructed along a line of vents extending NE from the Emmons Lake caldera. Pavlof and its twin volcano to the NE, 2142-m-high Pavlof Sister, form a dramatic pair of symmetrical, glacier-covered stratovolcanoes that tower above Pavlof and Volcano bays. A third cone, Little Pavlof, is a smaller volcano on the SW flank of Pavlof volcano, near the rim of Emmons Lake caldera. Unlike Pavlof Sister, Pavlof has been frequently active in historical time, typically producing Strombolian to Vulcanian explosive eruptions from the summit vents and occasional lava flows. The active vents lie near the summit on the north and east sides. The largest historical eruption took place in 1911, at the end of a 5-year-long eruptive episode, when a fissure opened on the N flank, ejecting large blocks and issuing lava flows. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9K5evT6z8$ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-RMZbTuM$> Semisopochnoi | Aleutian Islands (USA) | 51.93°N, 179.58°E | Summit elev. 1221 m AVO reported that an eruption at Semisopochnoiâ??s North Cerberus crater was ongoing during 4-10 August, characterized by daily explosions, ash plumes, and sulfur dioxide emissions identified in satellite images. Multiple energetic explosions were detected almost daily in seismic and infrasound data. An ash cloud rose to 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted 33 km NE during 3-4 August. Ash emissions were also visible in webcam images and photographed by an observer S of the island. An ash cloud was generated at 2123 on 4 August and was visible in satellite data until 0250 on 5 August, drifting 180 km SE over Gareloi and southern Tanaga Island. A small ash cloud at 2040 on 6 August drifted 50 km beyond the N crater vent and quickly dissipated. Another small ash cloud at 2103 caused ashfall on the webcam located 5 km NE about 30 minutes later. Ash-and-steam emissions were visible in webcam images until 2333. A large infrasound signal was recorded at 0653 on 8 August, though weather conditions prevented visual confirmation of emissions. A possible small ash cloud was visible in a satellite image at 0700. At least three separate explosions were recorded at 1714 on 8 August and 0339 and 0417 on 9 August. A small ash cloud at 900 m (3,000 ft) a.s.l. was visible in satellite images on the morning of 9 August. There were 10 explosions recorded during 9-10 August; small ash-and-steam emissions were visible in the webcam and small low-level plumes were occasionally identified in satellite data. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch. Geologic Summary. Semisopochnoi, the largest subaerial volcano of the western Aleutians, is 20 km wide at sea level and contains an 8-km-wide caldera. It formed as a result of collapse of a low-angle, dominantly basaltic volcano following the eruption of a large volume of dacitic pumice. The high point of the island is Anvil Peak, a double-peaked late-Pleistocene cone that forms much of the island's northern part. The three-peaked Mount Cerberus was constructed within the caldera during the Holocene. Each of the peaks contains a summit crater; lava flows on the N flank of Cerberus appear younger than those on the south side. Other post-caldera volcanoes include the symmetrical Sugarloaf Peak SSE of the caldera and Lakeshore Cone, a small cinder cone at the edge of Fenner Lake in the NE part of the caldera. Most documented eruptions have originated from Cerberus, although Coats (1950) considered that both Sugarloaf and Lakeshore Cone could have been recently active. Source: US Geological Survey Alaska Volcano Observatory (AVO) https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9K5evT6z8$ <https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-RMZbTuM$> Suwanosejima | Ryukyu Islands (Japan) | 29.638°N, 129.714°E | Summit elev. 796 m JMA reported that 13 explosions at Suwanosejima's Ontake Crater produced eruption plumes that rose as high as 3.8 km above the crater rim during 30 July-6 August. Large volcanic bombs were ejected 500 m from the crater. Crater incandescence was visible nightly. The Alert Level remained at 2 and the public was warned to stay 1 km away from the crater. Geologic Summary. The 8-km-long, spindle-shaped island of Suwanosejima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two historically active summit craters. The summit is truncated by a large breached crater extending to the sea on the east flank that was formed by edifice collapse. Suwanosejima, one of Japan's most frequently active volcanoes, was in a state of intermittent strombolian activity from Otake, the NE summit crater, that began in 1949 and lasted until 1996, after which periods of inactivity lengthened. The largest historical eruption took place in 1813-14, when thick scoria deposits blanketed residential areas, and the SW crater produced two lava flows that reached the western coast. At the end of the eruption the summit of Otake collapsed forming a large debris avalanche and creating the horseshoe-shaped Sakuchi caldera, which extends to the eastern coast. The island remained uninhabited for about 70 years after the 1813-1814 eruption. Lava flows reached the eastern coast of the island in 1884. Only about 50 people live on the island. Source: Japan Meteorological Agency (JMA) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KOGV4Cx0$ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-oDqisaA$> Tengger Caldera | Eastern Java (Indonesia) | 7.942°S, 112.95°E | Summit elev. 2329 m PVMBG reported that during 3-9 August white steam-and-gas plumes rose as high as 400 m above Tengger Calderaâ??s Bromo cone and drifted NW, W, and SW. Thermal anomalies were visible in satellite images on 3 and 8 August; a weaker anomaly was also visible on 29 July. The Alert Level remained at 2 (on a scale of 1-4), and visitors were warned to stay outside of a 1-km radius of the crater. Geologic Summary. The 16-km-wide Tengger caldera is located at the northern end of a volcanic massif extending from Semeru volcano. The massive volcanic complex dates back to about 820,000 years ago and consists of five overlapping stratovolcanoes, each truncated by a caldera. Lava domes, pyroclastic cones, and a maar occupy the flanks of the massif. The Ngadisari caldera at the NE end of the complex formed about 150,000 years ago and is now drained through the Sapikerep valley. The most recent of the calderas is the 9 x 10 km wide Sandsea caldera at the SW end of the complex, which formed incrementally during the late Pleistocene and early Holocene. An overlapping cluster of post-caldera cones was constructed on the floor of the Sandsea caldera within the past several thousand years. The youngest of these is Bromo, one of Java's most active and most frequently visited volcanoes. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KFTPMiHA$ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-P6hCX-k$> ; Sentinel Hub https://urldefense.com/v3/__https://sentinel-hub.com/explore/sentinel-playground__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9K-1WayjA$ <https://urldefense.com/v3/__https://sentinel-hub.com/explore/sentinel-playground__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-mkXwUHM$> Whakaari/White Island | North Island (New Zealand) | 37.52°S, 177.18°E | Summit elev. 294 m GeoNet maintained the Volcanic Alert Level at 2 and the Aviation Color Code at Yellow for Whakaari/White Island based on continuing unrest and data collected during a recent overflight. In a 9 August report GeoNet noted that temperatures in the vent area remained high at 520 degrees Celsius; crater incandescence continued to be visible in webcams images at night. Moderate levels of carbon dioxide and sulfur dioxide emissions measured downwind of the volcano were similar to levels observed on 20 July. Low levels of ground deformation around the active vent and lake area were identified in satellite radar data. The interpretation of the data suggested a shallow magma intrusion beginning in June. Very steamy conditions obscured views of the vent area. 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 https://urldefense.com/v3/__http://www.geonet.org.nz/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9Ksppa2n0$ <https://urldefense.com/v3/__http://www.geonet.org.nz/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-cTfZaE4$> Ongoing Activity Aira | Kyushu (Japan) | 31.593°N, 130.657°E | Summit elev. 1117 m JMA reported that incandescence from Minamidake Crater (at Aira Calderaâ??s Sakurajima volcano) was visible at night during 2-9 August. Very small eruptive events were recorded during 2-6 August. The sulfur dioxide emission rate was relatively elevated at 1,500 tons per day on 4 August. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater. Geologic Summary. The Aira caldera in the northern half of Kagoshima Bay contains the post-caldera Sakurajima volcano, one of Japan's most active. Eruption of the voluminous Ito pyroclastic flow accompanied formation of the 17 x 23 km caldera about 22,000 years ago. The smaller Wakamiko caldera was formed during the early Holocene in the NE corner of the Aira caldera, along with several post-caldera cones. The construction of Sakurajima began about 13,000 years ago on the southern rim of Aira caldera and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kitadake summit cone ended about 4850 years ago, after which eruptions took place at Minamidake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu's largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76. Source: Japan Meteorological Agency (JMA) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KOGV4Cx0$ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-oDqisaA$> Asamayama | Honshu (Japan) | 36.406°N, 138.523°E | Summit elev. 2568 m On 6 August JMA lowered the Alert Level for Asamayama to 1 (on a scale of 1-5), noting that the number of shallow volcanic earthquakes had been decreasing, sulfur dioxide gas emissions had been low, and deformation on the W flank had stabilized. JMA reminded the public to stay 500 m away from the crater. Geologic Summary. Asamayama, Honshu's most active volcano, overlooks the resort town of Karuizawa, 140 km NW of Tokyo. The volcano is located at the junction of the Izu-Marianas and NE Japan volcanic arcs. The modern Maekake cone forms the summit and is situated east of the horseshoe-shaped remnant of an older andesitic volcano, Kurofuyama, which was destroyed by a late-Pleistocene landslide about 20,000 years before present (BP). Growth of a dacitic shield volcano was accompanied by pumiceous pyroclastic flows, the largest of which occurred about 14,000-11,000 BP, and by growth of the Ko-Asama-yama lava dome on the east flank. Maekake, capped by the Kamayama pyroclastic cone that forms the present summit, is probably only a few thousand years old and has an historical record dating back at least to the 11th century CE. Maekake has had several major plinian eruptions, the last two of which occurred in 1108 (Asamayama's largest Holocene eruption) and 1783 CE. Source: Japan Meteorological Agency (JMA) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KOGV4Cx0$ <https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-oDqisaA$> Copahue | Central Chile-Argentina border | 37.856°S, 71.183°W | Summit elev. 2953 m SERNAGEOMIN and SEGEMAR reported increased activity at Copahue during 9-10 August, characterized as increased gas emissions, ash emissions, and crater incandescence. During the morning of 9 August gas-and-steam emissions increased and sulfur dioxide flux was as high as 7,200 tons per day. Crater incandescence was visible in nighttime webcam views and was intense during the early hours of 10 August. An ash plume rose 300 m above the crater rim and drifted N and NNW. Seismicity remained stable; data suggested no rising magma. The Alert Level remained at Green (the lowest level on a four-color scale). Geologic Summary. Volcán Copahue is an elongated composite cone constructed along the Chile-Argentina border within the 6.5 x 8.5 km wide Trapa-Trapa caldera that formed between 0.6 and 0.4 million years ago near the NW margin of the 20 x 15 km Pliocene Caviahue (Del Agrio) caldera. The eastern summit crater, part of a 2-km-long, ENE-WSW line of nine craters, contains a briny, acidic 300-m-wide crater lake (also referred to as El Agrio or Del Agrio) and displays intense fumarolic activity. Acidic hot springs occur below the eastern outlet of the crater lake, contributing to the acidity of the RÃo Agrio, and another geothermal zone is located within Caviahue caldera about 7 km NE of the summit. Infrequent mild-to-moderate explosive eruptions have been recorded since the 18th century. Twentieth-century eruptions from the crater lake have ejected pyroclastic rocks and chilled liquid sulfur fragments. Sources: Servicio Nacional de GeologÃa y MinerÃa (SERNAGEOMIN) https://urldefense.com/v3/__http://www.sernageomin.cl/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KGqkfZVI$ <https://urldefense.com/v3/__http://www.sernageomin.cl/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-ywAj1sA$> ; Servicio Geológico Minero Argentino (SEGEMAR) https://urldefense.com/v3/__http://www.segemar.gov.ar/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KXRDkJLA$ <https://urldefense.com/v3/__http://www.segemar.gov.ar/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-zzZ21sM$> Dukono | Halmahera (Indonesia) | 1.693°N, 127.894°E | Summit elev. 1229 m PVMBG reported that during 3-4 and 6 August white-and-gray ash plumes from Dukono rose 100-500 m above the summit and drifted E and W. Weather conditions prevented visual observations during 5 and 7-10 August. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km exclusion zone. Geologic Summary. Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, occurred from 1933 until at least the mid-1990s, when routine observations were curtailed. During a major eruption in 1550, a lava flow filled in the strait between Halmahera and the north-flank cone of Gunung Mamuya. This complex volcano presents a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m crater that has also been active during historical time. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KFTPMiHA$ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-P6hCX-k$> Ebeko | Paramushir Island (Russia) | 50.686°N, 156.014°E | Summit elev. 1103 m According to volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions during 29 July, 1 August, and 3-5 August produced ash plumes that rose as high as 2.5 km (8,200 ft) a.s.l. and drifted S and SE. A thermal anomaly was identified in satellite images on 1 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Geologic Summary. The flat-topped summit of the central cone of Ebeko volcano, one of the most active in the Kuril Islands, occupies the northern end of Paramushir Island. Three summit craters located along a SSW-NNE line form Ebeko volcano proper, at the northern end of a complex of five volcanic cones. Blocky lava flows extend west from Ebeko and SE from the neighboring Nezametnyi cone. The eastern part of the southern crater contains strong solfataras and a large boiling spring. The central crater is filled by a lake about 20 m deep whose shores are lined with steaming solfataras; the northern crater lies across a narrow, low barrier from the central crater and contains a small, cold crescentic lake. Historical activity, recorded since the late-18th century, has been restricted to small-to-moderate explosive eruptions from the summit craters. Intense fumarolic activity occurs in the summit craters, on the outer flanks of the cone, and in lateral explosion craters. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KZvRaCns$ <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-baRGmQM$> Etna | Sicily (Italy) | 37.748°N, 14.999°E | Summit elev. 3320 m INGV reported continuing activity at Etnaâ??s summit craters during 2-8 August, mainly from the Northeast Crater (NEC) and the Southeast Crater (SEC). Gas emissions rose from Voragine Crater and from two active craters in Bocca Nuova. A series of discontinuous ash emissions from NEC began at 1350 on 4 August and lasted about two hours. An ash plume rose to 1.8 km (6,000 ft) a.s.l. and drifted NE. Similar but less intense ash emissions were visible on 5 August. The reddish mostly fine-grained material emitted from NEC was erupted when no thermal anomalies were present in the crater, suggesting that they were the result of landslides rather than eruptive activity. Strombolian activity began at SEC at 2057 on 7 August and was characterized by isolated explosions and the ejection of incandescent material beyond the crater rim; activity ceased during the night. An explosion at 2056 on 8 August was followed by the resumption of Strombolian activity at 0030 on 9 August. Incandescent material was again ejected beyond the crater rim and an ash plume drifted SE. Geologic Summary. Mount Etna, towering above Catania, Sicily's second largest city, has one of the world's longest documented records of historical 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 horseshoe-shaped 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) https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KAvhIsS8$ <https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-UNeXteA$> Fuego | Guatemala | 14.473°N, 90.88°W | Summit elev. 3763 m INSIVUMEH reported that 4-13 explosions per hour were recorded during 3-10 August at Fuego, generating ash plumes as high as 1.1 km above the crater rim and shock waves that often rattled buildings around the volcano. Ash plumes mostly drifted as far as 15 km W and SW, causing daily ashfall in several areas downwind, including Morelia (9 km SW), Panimaché (8 km SW), Santa SofÃa (12 km SW), Yucales (12 km SW), El Porvenir (8 km ENE), Finca Palo Verde, Sangre de Cristo (8 km WSW), and San Pedro Yepocapa (8 km NW). Block avalanches descended the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Las Lajas (SE), and Honda drainages, often reaching vegetated areas. Explosions ejected incandescent material 100-400 m above the summit during 4-6 and 9-10 August. At 1700 on 6 August a lahar descended the Las Lajas drainage, carrying fine material along with tree branches and blocks 1-2 m in diameter. Geologic Summary. Volcán Fuego, one of Central America's most active volcanoes, is also one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between Fuego and Acatenango to the north. Construction of Meseta dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at the mostly andesitic Acatenango. Eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. Frequent vigorous historical eruptions have been recorded since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9K2WwfLJw$ <https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-HCANeuM$> Karymsky | Eastern Kamchatka (Russia) | 54.049°N, 159.443°E | Summit elev. 1513 m KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 29 and 31 July, and 1, 2, and 4 August. Weather clouds prevented satellite observations on the days in between as well as during 5-6 August. Gas, steam, and ash plumes from explosions rose 2.5 km (8,200 ft) a.s.l. and drifted 75 km SE during 1 and 4-5 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KZvRaCns$ <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-baRGmQM$> Lewotolok | Lembata Island (Indonesia) | 8.274°S, 123.508°E | Summit elev. 1431 m PVMBG reported that the Strombolian eruption at Lewotolok continued during 3-10 August. Daily white, gray, and sometimes black plumes rose as high as 1.5 km above the summit and drifted in multiple directions. Banging noises associated with eruptions were reported almost daily. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater. Geologic Summary. The Lewotolok (or Lewotolo) stratovolcano occupies the eastern end of an elongated peninsula extending north into the Flores Sea, connected to Lembata (formerly Lomblen) Island by a narrow isthmus. It is symmetrical when viewed from the north and east. A small cone with a 130-m-wide crater constructed at the SE side of a larger crater forms the volcano's high point. Many lava flows have reached the coastline. Eruptions recorded since 1660 have consisted of explosive activity from the summit crater. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KFTPMiHA$ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-P6hCX-k$> Merapi | Central Java (Indonesia) | 7.54°S, 110.446°E | Summit elev. 2910 m BPPTKG reported that the lava dome just below Merapiâ??s SW rim and the lava dome in the summit crater both remained active during 30 July-5 August. The SW rim dome volume was an estimated 1.895 million cubic meters and about 3 m tall. A total of seven pyroclastic flows descended the SW flank as far as 2 km and as many as 84 lava avalanches traveled a maximum of 2 km SW. Multiple pyroclastic flows traveled 2-3 km down the SW flank on 8 August and ash plumes rose 1 km above the summit. According to a news article ashfall was reported in several local communities. Pyroclastic flows traveled up to 3 km down the SW flanks multiple times during 9-10 August. BNPB noted that a small fire on the SW flank, 2.5 km from the crater, was set by ejected incandescent material; the fire burned an area of only 30 square meters during 25-26 August. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 5 km away from the summit. 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. Sources: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG) https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KYwzomaQ$ <https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-ctf6KA8$> ; Forbes https://urldefense.com/v3/__https://www.forbes.com/sites/davidbressan/2021/08/08/indonesias-most-volatile-volcano-mount-merapi-erupts/?sh=522558132250__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9K5DfhQ5I$ <https://urldefense.com/v3/__https://www.forbes.com/sites/davidbressan/2021/08/08/indonesias-most-volatile-volcano-mount-merapi-erupts/?sh=522558132250__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-okGuzEU$> Popocatepetl | Mexico | 19.023°N, 98.622°W | Summit elev. 5393 m CENAPRED reported that each day during 4-10 August there were 30-92 steam-and-gas emissions from Popocatépetl. The plumes drifted mainly W and some contained ash. A minor explosion was recorded at 0652 on 4 August. At 2137 on 6 August a moderately-sized explosion produced a plume, thought the height and drift direction were obscured by weather conditions. Incandescent fragments ejected from the crater were seen falling on the flanks not far from the crater rim. Weather conditions again prevented views of an explosion at 0258 on 8 August. The Alert Level remained at Yellow, Phase Two (middle level on a three-color scale). Geologic Summary. Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, rises 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 400 x 600 m wide crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano. At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas to the south. The modern volcano was constructed south of the late-Pleistocene to Holocene El Fraile cone. Three major Plinian eruptions, the most recent of which took place about 800 CE, have occurred since the mid-Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since Pre-Columbian time. Source: Centro Nacional de Prevencion de Desastres (CENAPRED) https://urldefense.com/v3/__https://www.gob.mx/cenapred__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KCAC63sY$ <https://urldefense.com/v3/__https://www.gob.mx/cenapred__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-GlcDUJo$> Raung | Eastern Java (Indonesia) | 8.119°S, 114.056°E | Summit elev. 3260 m PVMBG reported that neither explosive nor effusive activity had been recorded at Raung since February, and emissions were not observed during 1 July-8 August. Seismicity had declined and deformation data indicated a trend of deflation. The Alert Level was lowered to 1 (on a scale of 1-4) on 9 August, and the public was warned to stay away from the crater. Geologic Summary. Raung, one of Java's most active volcanoes, is a massive stratovolcano in easternmost Java that was constructed SW of the rim of Ijen caldera. The unvegetated summit is truncated by a dramatic steep-walled, 2-km-wide caldera that has been the site of frequent historical eruptions. A prehistoric collapse of Gunung Gadung on the W flank produced a large debris avalanche that traveled 79 km, reaching nearly to the Indian Ocean. Raung contains several centers constructed along a NE-SW line, with Gunung Suket and Gunung Gadung stratovolcanoes being located to the NE and W, respectively. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KFTPMiHA$ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-P6hCX-k$> Santa Maria | Guatemala | 14.757°N, 91.552°W | Summit elev. 3745 m INSIVUMEH reported that during 4-10 August daily explosions at Santa MarÃaâ??s Santiaguito lava-dome complex generated ash plumes that rose as high as 1 km above the summit and drifted as far as 7 km SW and W. Incandescence from the complex was occasionally visible at night. Collapses of blocky lava from Caliente dome sent avalanches down the S, SW, and W flanks, often reaching the base, and caused minor ashfall mostly on the volcanoâ??s flank. Ashfall was also reported in San Marcos (8 km SW), Loma Linda Palajunoj (6 km WSW), and surrounding farms during 3-4 and 8-9 August. Heavy rainfall on 7 August caused a lahar to descend the Tambor River, carrying branches, tree trunks, and blocks up to 3 m in diameter. Geologic Summary. Symmetrical, forest-covered Santa MarÃa volcano is part of a chain of large stratovolcanoes that rise above the Pacific coastal plain of Guatemala. The sharp-topped, conical profile is cut on the SW flank by a 1.5-km-wide crater. The oval-shaped crater extends from just below the summit to the lower flank, and was formed during a catastrophic eruption in 1902. The renowned Plinian eruption of 1902 that devastated much of SW Guatemala followed a long repose period after construction of the large basaltic-andesite stratovolcano. The massive dacitic Santiaguito lava-dome complex has been growing at the base of the 1902 crater since 1922. Compound dome growth at Santiaguito has occurred episodically from four vents, with activity progressing W towards the most recent, Caliente. Dome growth has been accompanied by almost continuous minor explosions, with periodic lava extrusion, larger explosions, pyroclastic flows, and lahars. Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9K2WwfLJw$ <https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-HCANeuM$> Semeru | Eastern Java (Indonesia) | 8.108°S, 112.922°E | Summit elev. 3657 m Semeru continued to erupt during 4-10 August. Inclement weather often prevented visual observations, though during 4-7 August avalanches of lava from the end of the flow in the summit crater were seen traveling 200 m SE down the Kobokan drainage. Gray-and-white plumes rose 500 m above the summit and drifted SW during 6-7 and 9 August. The Alert Level remained at 2 (on a scale of 1-4), with a general exclusion zone of 1 km and extensions to 5 km in the SSE sector. Geologic Summary. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano. Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KFTPMiHA$ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-P6hCX-k$> ; Darwin Volcanic Ash Advisory Centre (VAAC) https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KGGNcbdw$ <https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-p_vxm5c$> Sheveluch | Central Kamchatka (Russia) | 56.653°N, 161.36°E | Summit elev. 3283 m KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 30 July-6 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Geologic Summary. The high, isolated massif of Sheveluch volcano (also spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group. The 1300 km3 volcano is one of Kamchatka's largest and most active volcanic structures. The summit of roughly 65,000-year-old Stary Shiveluch is truncated by a broad 9-km-wide late-Pleistocene caldera breached to the south. Many lava domes dot its outer flanks. The Molodoy Shiveluch lava dome complex was constructed during the Holocene within the large horseshoe-shaped caldera; Holocene lava dome extrusion also took place on the flanks of Stary Shiveluch. At least 60 large eruptions have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Widespread tephra layers from these eruptions have provided valuable time markers for dating volcanic events in Kamchatka. Frequent collapses of dome complexes, most recently in 1964, have produced debris avalanches whose deposits cover much of the floor of the breached caldera. Source: Kamchatkan Volcanic Eruption Response Team (KVERT) https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KZvRaCns$ <https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-baRGmQM$> Sinabung | Indonesia | 3.17°N, 98.392°E | Summit elev. 2460 m PVMBG reported that on most days during 3-10 August white gas-and-steam plumes from Sinabung rose as high as 500 m above the summit and drifted in multiple directions. Avalanches of lava traveled 500-700 m down the E and SE flanks during 4-7 August. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km exclusion zone. Geologic Summary. Gunung Sinabung is a Pleistocene-to-Holocene stratovolcano with many lava flows on its flanks. The migration of summit vents along a N-S line gives the summit crater complex an elongated form. The youngest crater of this conical andesitic-to-dacitic edifice is at the southern end of the four overlapping summit craters. The youngest deposit is a SE-flank pyroclastic flow 14C dated by Hendrasto et al. (2012) at 740-880 CE. An unconfirmed eruption was noted in 1881, and solfataric activity was seen at the summit and upper flanks in 1912. No confirmed historical eruptions were recorded prior to explosive eruptions during August-September 2010 that produced ash plumes to 5 km above the summit. Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!KpVI2C_oP4kPsWD5CUThJ-sSUTq-lS_NTemDucoqUyOphdEjkEkU7g9KFTPMiHA$ <https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!J98hsGUlLyVCTZ1uuOXRLFFQdJUC0pUrVXF5xhL8mbPj5bIIGfrmRr4-P6hCX-k$> 1-1-1-1-1-1-1-1-1-1-1-1-1-1 ============================================================== 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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