Volcanos

Roundup of Global Volcanic Activity - Ongoing Activity for the week of 6 September-12 September 2017

Aira | Kyushu (Japan) : JMA reported that 30 explosive events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 4-11 September ejected material as far as 800 m. Ash plumes rose as high as 2.2 km above the crater rim. Crater incandescence was observed most nights. The Alert Level remained at 3 (on a 5-level scale).

Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 11-12 September an ash plume from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted NW.

Bezymianny | Central Kamchatka (Russia) : KVERT reported that during 1-8 September a thermal anomaly over Bezymianny was identified daily in satellite images. A lava flow continued to flow down the W flank of the dome; incandescence from the dome was visible at night. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Bogoslof | Fox Islands (USA) : AVO reported that during 6-12 September nothing significant was observed in mostly cloudy satellite images of Bogoslof, and no activity was detected in seismic or infrasound data. The 8 September report noted that the crater lake had been bisected by a narrow isthmus of land. Elevated surface temperatures were identified in one satellite image during 10-11 September. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Cleveland | Chuginadak Island (USA) : AVO reported that during 6-12 September nothing significant was observed in often cloudy satellite images and web camera views of Cleveland; minor steaming was noted during 10-11 September. In addition, nothing noteworthy was detected in seismic or infrasound data. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 6-10 and 12 September ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted SW, W, and NW.

Ebeko | Paramushir Island (Russia) : Based on observations by volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions on 2 September generated ash plumes that rose 4 km (13,100 ft) a.s.l. Explosions during 3 and 6-7 September produced ash plumes that rose 2.1 km (6,900 ft) a.s.l. Minor amounts of ash fell in Severo-Kurilsk during 2-3 and 6-7 September. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 6-12 September HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater, though a deflationary trend the second half of the week caused the lake level to mostly drop. Several rockfalls and collapses of the inner crater wall veneer were noted during 7-10 September; frequent rockfalls were not uncommon during periods of lake level lowering. Webcams recorded incandescence from long-active sources within Pu'u 'O'o Crater and from a small lava pond in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu'u 'O'o Crater's E flank, continued to enter the ocean at Kamokuna. Surface lava flows were active above and on the pali, and on the coastal plain. HVO noted that cracks running parallel to the coastline underscored the potential for bench collapse into the sea.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that on 7 September explosions at Klyuchevskoy recorded by a webcam generated ash plumes that rose as high as 6 km (19,700 ft) a.s.l. and drifted about 50 km NE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Poas | Costa Rica : OVSICORI-UNA reported that an event at Poás at 0820 on 13 September generated plume that rose 300 m above the crater rim.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya was slightly lower compared to the previous week; there was an average of 38 explosions recorded per day during 4-10 September. The earthquakes were dominated by long-period signals, with fewer numbers of hybrid events and emission signals. Gas-and-ash plumes rose 3.5 km above the crater rim and drifted no more than 40 km SE. The MIROVA system detected five thermal anomalies. The report warned the public not to approach the crater within a 12-km radius.

Sangay | Ecuador : Based on information from the Guayaquil MWO, the Washington VAAC reported that on 6 September an emission from Sangay rose 7.3 km (24,000 ft) a.s.l.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified daily in satellite images during 2-3 and 6-7 September. Two explosive events on 7 September generated ash plumes that rose 8-10 km (26,200-32,800 ft) a.s.l. and drifted NE, SE, and S. The Aviation colour Code remained at Orange.

Sinabung | Indonesia : Based on observations by PVMBG, webcam and satellite images, and model data, the Darwin VAAC reported that during 6-8 and 12 September ash plumes from Sinabung rose 3-5.5 km (10,000-18,000 ft) a.s.l. and drifted W, NW, and E.

Suwanosejima | Ryukyu Islands (Japan) : Based on JMA notices and satellite-image analyses, the Tokyo VAAC reported explosions on 6 September generated plums that rose 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted E.

Turrialba | Costa Rica : OVSICORI-UNA reported that an event at Turrialba at 0730 on 11 September generated a plume that rose 500 m above the crater rim and drifted N. Another event at 0820 on 13 September passively produced an ash plume that rose 100 m and drifted NW.