Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 20 September-26 September 2017

Aira | Kyushu (Japan) : JMA reported that 29 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) detected during 19-22 September sometimes produced plumes that rose 1.8 km. At 0445 on 24 September an eruption plume rose 1 km. The Alert Level remained at 3 (on a 5-level scale).

Bezymianny | Central Kamchatka (Russia) : KVERT reported that during 15-22 September lava continued to flow down the W flank of Bezymianny's dome, and incandescence from the dome was visible at night. A thermal anomaly was identified in satellite images during 15-19 September. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Bogoslof | Fox Islands (USA) : AVO reported that during 20-26 September nothing significant was observed in partly to mostly cloudy satellite images of Bogoslof, and no activity was detected in seismic or infrasound data. Weakly elevated surface temperatures were identified in satellite images during 22-23 September, indicating ongoing unrest. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Cleveland | Chuginadak Island (USA) : AVO reported that during 20-24 September nothing significant was observed in satellite images and web camera views of Cleveland, and nothing noteworthy was detected in seismic or infrasound data. Minor steaming was noted during 22-24 September. A three-minute-long explosion that began at 1747 on 25 September was detected by seismic and infrasound sensors. Satellite data 30 minutes later suggested that a volcanic cloud likely containing ash rose to 4.6 km (15,000 ft) a.s.l. and drifted S. 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 20-26 September ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted in multiple directions.

Ebeko | Paramushir Island (Russia) : Based on observations by volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions during 15-17 September generated ash plumes that rose 3 km (10,000 ft) a.s.l. Minor amounts of ash fell in Severo-Kurilsk on 16 and 18 September. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Karymsky was identified in satellite images during 15-16 September. An ash cloud rose 7 km (23,000 ft) a.s.l. and drifted for about 100 km NE on 19 September. The Aviation colour Code was raised to Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 20-26 September HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. 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. During 23-24 September a short-lived breakout above the ocean entry disrupted the ramp and produced a brief "firehose" of lava.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that during 16-17 September a weak thermal anomaly at Klyuchevskoy was identified in satellite images. KVERT noted that the last time ash was emitted from the volcano was on 7 September; the Aviation colour Code was lowered to Yellow (the second lowest level on a four-colour scale).

Langila | New Britain (Papua New Guinea) : Based on analyses of satellite imagery and wind model data, the Darwin VAAC reported that during 22-23 September ash plumes from Langila rose 2.1 km (7,000 ft) a.s.l. and drifted NNW.

Nevados de Chillan | Chile : Servicio Nacional de Geología and Minería (SERNAGEOMIN) Observatorio Volcanológico de Los Andes del Sur (OVDAS) reported that a phreatic explosion at Nevados de Chillán's Volcán Arrau dome complex was recorded by a webcam on 21 September. An explosion ejected gas and tephra on 23 September. The Alert Level remained at Yellow, the middle level on a three-colour scale, and the public was reminded not to approach the craters within a 3-km radius.

Pacaya | Guatemala : INSIVUMEH reported that during 21-22 September Strombolian explosions at Pacaya’s Mackenney cone ejected material as high as 100 m above the crater rim. During 23-24 September the seismic network recorded Strombolian explosion signals.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya increased; there was an average of 45 explosions recorded per day during 18-24 September. The earthquakes were dominated by long-period events, with fewer signals indicating emissions and hybrid events. Gas-and-ash plumes rose 3.5 km above the crater rim and drifted no more than 40 km E and SE. The MIROVA system detected seven thermal anomalies. The report warned the public not to approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified daily in satellite images during 15-22 September. 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 22-23 September ash plumes from Sinabung rose 3.4-4 km (11,000-13,000 ft) a.s.l. and sometimes drifted E and SE. On 25 September ash plumes rose 6.4 km (21,000 ft) a.s.l. and drifted ESE.

Turrialba | Costa Rica : OVSICORI-UNA reported that events at Turrialba at 1112 on 25 September and 0910 on 26 September generated plumes that rose 300 m above the crater rim and drifted NW.

Ulawun | New Britain (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that on 25 September a minor ash plume from Ulawun rose 3 km (10,000 ft) a.s.l. and drifted WSW.