Friday 26 June 2020

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the Week 17 June 2020 – 23 June 2020

Aira | Kyushu (Japan) : JMA reported that very small eruptive events were recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 19-22 June. The Alert Level remained at 3 (on a 5-level scale).

Cleveland | Chuginadak Island (USA) : AVO reported that no additional volcanic activity was detected at Cleveland after the short-lived explosion recorded on 1 June. The Volcano Alert Level was lowered to Advisory and the Aviation colour Code was lowered to Yellow.

Copahue | Central Chile-Argentina border : On 17 June OVDAS-SERNAGEOMIN reported increased activity at Copahue during the previous days, characterized by low-altitude gas emissions containing particulate matter. A period of increased seismicity was recorded in the afternoon on 16 June accompanied by crater incandescence and emissions visible in webcam images. The report noted that very-long-period earthquakes had been recorded in previous months, and a series of volcano-related seismic events were detected in an area SSW of the volcano on 20 March. Additionally, satellite images showed a reduction in the size of the crater lake. These recent changes coupled with increased seismicity prompted SERNAGEOMIN to raise the Alert Level to Yellow (second lowest level on a four-colour scale) and restrict access to an area within 1 km of El Agrio Crater. ONEMI raised a Yellow Alert (the middle level on a three-colour scale) for residents of the Alto Biobío municipality.

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 16-23 June ash plumes from Dukono rose to 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted NW and W. 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.

Ebeko | Paramushir Island (Russia) : KVERT reported that a thermal anomaly over Ebeko was identified in satellite images on 14, 16, and 18 June. Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions on 17 June that sent ash plumes up to 2 km (6,600 ft) a.s.l. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Ibu | Halmahera (Indonesia) : The Darwin VAAC reported that during 20-21 June ash plumes from Ibu rose to 1.8 km (6,000 ft) a.s.l. and drifted NW and W based on satellite images and weather models. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater, and 3.5 km away on the N side.

Kanlaon | Philippines : PHIVOLCS reported that ground deformation data from continuous GPS measurements at Kanlaon indicated slight deflation of the lower and middle flanks since January. Tilt data from instruments on the SE flank recorded continuing deflation on the lower flanks and inflation of the mid-flank since April 2020. White steam plumes rose 100-200 m above the summit and drifted NW and SW. The seismic network recorded as many as 10 volcanic earthquakes per day during 17-21 June. A series of earthquakes beneath the lower W flank began at 1603 on 21 June, and by 0800 the next morning there were a total of 136 events recorded. Five of the earthquakes (recorded at 0101, 0104, 0134, 0206, and 0507 on 22 June) were M 3-4.7, and were felt at Intensities II to IV in La Carlota City and Bago City, Negros Occidental, and Canlaon City, Negros Oriental. During 22-23 June there were a total of 104 volcano-tectonic earthquakes beneath the W flank. The Alert Level remained at 1 (on a scale of 0-5) and PHIVOLCS reminded the public to remain outside of the 4-km-radius Permanent Danger Zone.

Kick ’em Jenny | North of Grenada : The University of the West Indies (UWI) Seismic Research Centre (SRC) and the National Disaster Management Agency (NaDMA) reported that a period of elevated seismicity at Kick ’em Jenny was recorded over a seven-day period in June. According to a news article, only 29 earthquakes were recorded during April-May all with magnitudes of 1.6-2. During 5-12 June there were 1,384 recorded earthquakes with magnitudes as high as 1.8. The Alert Level remained at Yellow (the second lowest level on a four-colour scale) and the maritime exclusion zone did not change from the radius of 1.5 km.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that Strombolian activity at Klyuchevskoy was visible during 12-19 June along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. Avalanches of material on the S side of the lava flow were sometimes visible. Aviation colour Code remained at Orange.

Nishinoshima  | Japan : The Tokyo VAAC reported that ash plumes from Nishinoshima rose to 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted NE and E. The marine exclusion zone was defined as a radius of about 2.6 km from the island.

Merapi | Central Java (Indonesia) : BPPTKG reported that two explosions at Merapi were recorded at 0913 and 0927 on 21 June; the first lasted under six minutes and the second lasted under two minutes. A dense ash plume rose around 6 km above the summit and drifted W, causing ashfall in areas downwind including in the districts of Magelang and Kulonprogo, and as far as the Girimulyo District (45 km). The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to stay outside of the 3-km exclusion zone.

Nishinoshima | Japan : The Tokyo VAAC reported that ash plumes from Nishinoshima rose to 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted NE and E. The marine exclusion zone was defined as a radius of about 2.6 km from the island.

Pacaya | Guatemala : INSIVUMEH reported that during 17-19 June Strombolian explosions at Pacaya’s Mackenney Crater ejected material as high as 100 m above the crater rim and continued to build a cone in the crater. Active lava flows were 250 m long on the N flank and 200 m long on the S flank by 19 June. In a special report INSIVUMEH noted that increased on 20 June accompanying active lava flows that traveled 650 m SW and 200 m NW by the next day. During 20-23 June Strombolian explosions ejected incandescent material as high as 200 m above the summit and produced ash plumes that rose 100 m. The explosions were heard in areas up to 5 km away.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported that periodic phreatic explosions at Rincón de la Vieja continued to be recorded by the seismic network and webcams during 16-23 June. Several small eruptive events were recorded during 16-17 June; the largest event occurred at 1635 on 17 June and produced a plume that rose 1 km above the crater rim. Eruptive events were detected at 1442 on 19 June and 1046 on 23 June, though inclement weather conditions prevented visual confirmation.

Sangay | Ecuador : On 16 June the Servicio Nacional de Gestión de Riesgos y Emergencias (SNGRE) declared a Yellow Alert for the province of Chimborazo due to a recent increase in ashfall from Sangay. IG reported a continuing high level of activity during 16-22 June, though weather clouds often prevented visual observations. According to the IG and Washington VAAC notices ash plumes rose 570-870 m above the summit and drifted W and SW. Incandescent blocks descending the SE flank were seen through breaks in cloud cover overnight during 17-18 June. SNGRE reported that lahars in the Upano River in the morning of 21 June followed heavy rains two days earlier. In Macas (40 km SE) the lahars caused the closure of the E45 Macas-Puyo road, destroying a 27-m section and damaging a 30-m section, and the evacuation of 21 people.

Semeru | Eastern Java (Indonesia) : PVMBG and the Darwin VAAC reported that on most days during 18-23 June ash plumes from Semeru rose 300-500 m above the summit and drifted SE, S, SW, and W. The Alert Level remained at 2 (on a scale of 1-4), and the public was reminded to stay outside of the general 1-km radius from the summit and 4 km on the SSE flank.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 12-19 June. A webcam captured an explosion on 13 June that sent ash up to 5 km (16,400 ft) a.s.l. The ash cloud drifted 120 km NE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that nighttime incandescence at Suwanosejima’s Ontake Crater was occasionally visible during 12-19 June. An explosion was recorded on 18 June, though inclement weather conditions prevented visual confirmation. The Alert Level remained at 2 (on a 5-level scale).

Whakaari/White Island | North Island (New Zealand) : GeoNet reported that during the previous few months activity levels at Whakaari/White Island had gradually declined based on the volcano monitoring team’s collective interpretation of all the monitoring data. The Volcanic Alert Level was lowered to 1 on 16 June; the Aviation colour Code was lowered to Green on 22 June.



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