Volcanos

Roundup of Global Volcanic Activity - Ongoing Activity for the week of 9 August - 15 August 2017

Aira | Kyushu (Japan) : JMA reported 44 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 10-14 August, one of which was explosive. Material was ejected as high as 500 m and as far as 300 m. Ash plumes rose as high as 1.8 km above the crater rim. 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 9-10 and 13 August ash plumes from Bagana rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted W and NW. Plumes drifted 120 km W on 13 August.

Bezymianny | Central Kamchatka (Russia) : KVERT reported that during 4-11 August a daily thermal anomaly was identified over Bezymianny 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 on 9 August seismic and infrasound data suggested low-level eruptive activity at Bogoslof; weakly elevated surface temperatures and a minor steam emission were identified in satellite images. No significant activity was observed in cloudy satellite images, and no activity was detected in seismic, infrasound, or lightning data during 10-13 August. Two short pulses of tremor were detected (at 0853, lasting five minutes, and at 0913, lasting three minutes) in seismic data; seismicity returned to baseline levels afterwards. A sequence of seismic events began at 0000 on 15 August; no activity was observed in infrasound, lightning, or satellite data. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Cleveland | Chuginadak Island (USA) : AVO reported that elevated surface temperatures at Cleveland were identified in satellite data during 9-15 August; weather clouds occasionally obscured views. No significant activity was observed in seismic and infrasound data. On 11 August AVO noted that lava-dome growth had stopped or slowed, based on satellite observations. Steam emissions from the summit crater were occasionally visible in webcam images. 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 9-15 August ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted NW and W.

Fuego | Guatemala : CONRED reported that during 8-9 August the lava flow that had descended Fuego’s Ceniza (SSW) drainage was still active, producing avalanches of material and emissions. Explosions generated ash plumes that rose 650 m above the crater. According to INSIVUMEH ash plumes from explosions during 11-12 and 14-15 August rose 650-850 m and drifted 7-8 km W and SW. Ashfall was reported in areas downwind including in Panimache (8 km SW), Morelia (9 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), Yepocapa, and Sangre de Cristo (8 km WSW). Incandescent material was ejected 100-150 m above the crater rim, and caused avalanches of material that traveled down multiple ravines.

Ibu | Halmahera (Indonesia) : Based on PVMBG observations, the Darwin VAAC reported that on 15 August an ash plume from Ibu rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted N.

Karymsky | Eastern Kamchatka (Russia) : A thermal anomaly over Karymsky was identified in satellite images during 4 and 6-10 August, as well as ash plumes drifting about 70 km NE and SW during 4 and 7-9 August. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 9-15 August 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. The 61G lava flow, originating from a vent on Pu'u 'O'o Crater's E flank, continued to enter the ocean at Kamokuna. Slumping of seaward portions of the delta continued, and cracks running parallel to the coastline continued to widen. HVO warned of the potential for larger-scale delta collapses.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that ash plumes from Klyuchevskoy were identified in satellite images drifting 300 km SW, SE, and NE during 4 and 7-11 August. A thermal anomaly was identified on 4 and 7 August. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Langila | New Britain (Papua New Guinea) : Based on analyses of satellite imagery, the Darwin VAAC reported that on 9 August a minor ash emission from Langila rose 1.8 km (6,000 ft) a.s.l. and drifted N.

Manam | Papua New Guinea : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that on 13 August an ash plume from Manam rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted almost 40 km NW.

Nevado del Ruiz | Colombia : Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 8-14 August seismicity at Nevado del Ruiz continued to indicate unrest; seismicity decreased as compared to the previous week. Plumes of water vapor and gas continued to be emitted from the volcano. A gas-and-steam plume rose 450 m above the crater rim on 8 August and drifted NW. A thermal anomaly was identified on 14 August. The Alert Level remained at III (Yellow; the second lowest level on a four-colour scale).

Poas | Costa Rica : OVSICORI-UNA reported that during 11-14 August seismicity at Poás was characterized by low-amplitude tremor, some volcano-tectonic earthquakes, and high-frequency signals indicating gas emissions. Weather clouds mostly prevented visual observations.

Popocatepetl | Mexico : Each day during 9-13 and 15 August CENAPRED reported 97-355 and steam and gas emissions from Popocatépetl; the daily count increased to 702 on 14 June. Crater incandescence was visible on some nights. A small explosion at 0815 on 14 August produced a plume with low ash content that rose 500 m above the crater rim and drifted SW. Explosions at 1759 and 1805 generated ash plumes that rose 0.8 and 1.5 km, respectively, and drifted W. On 15 August an explosion produced an ash plume that rose 1 km and drifted WNW. The Alert Level remained at Yellow, Phase Two.

Reventador | Ecuador : During 9-15 August IG reported a high level of seismic activity including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions at Reventador. Steam, gas, and ash plumes rose as high as 550 m above the crater rim and drifted mainly W and SW. Incandescent blocks rolled as far as 800 m down the flanks. During 10-12 August pyroclastic flows traveled as far as 600 m down the ESE and W flanks. Weather clouds sometimes prevented visual observations.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya decreased compared to the previous week; there was an average of 49 explosions recorded per day during 7-13 August. The earthquakes were dominated by long-period signals, with fewer numbers of hybrid and tremor events recorded. Gas-and-ash plumes rose 3.2 km above the crater rim and drifted no more than 40 km NE and E. Sulfur dioxide flux was as high as 912 tons per day, recorded on 8 August. The MIROVA system detected 12 thermal anomalies. The report reminded the public not to approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly was identified daily in satellite images over Sheveluch during 4-11 August. Strong explosions on 8 August produced a large ash cloud (300 x 400 km in size) that rose as high as 10 km (32,800 ft) a.s.l. and drifted more than 550 km SSE during 8-9 August. Ashfall was reported in Klyuchi Village (50 km SW) on 8 August. The Aviation colour Code remained at Orange.

Sinabung | Indonesia : Based on PVMBG ground observations, the Jakarta MWO, satellite images, and wind data, the Darwin VAAC reported that during 9-10 and 13 August ash plumes from Sinabung rose 3.4-5.2 km (11,000-17,000 ft) a.s.l. and drifted W and ESE.

Turrialba | Costa Rica : OVSICORI-UNA reported that an event at Turrialba at 1607 on 9 August generated a plume that rose 200 m above the crater rim and drifted NW. The report noted that since 6 August a monitoring station in Coronado San José had been detecting the presence of ash in emissions. Sporadic and passive emissions of ash, water vapor, magmatic gases, and aerosols continued to be observed at least through 14 August.