Roundup of Global Volcanic Activity – Ongoing Activity for the week of 10 May – 16 May 2017
Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 10-14 May ash plumes from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted SW, W, NW, and E.
Bezymianny | Central Kamchatka (Russia) : KVERT reported gas-and-steam activity at Bezymianny during 5-12 May, and a thermal anomaly identified in satellite images during 5 and 8-9 May. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Bogoslof | Fox Islands (USA) : AVO reported that an increase in seismic and infrasound activity from Bogoslof was detected from stations on nearby islands starting at 2232 on 16 May, suggesting the beginning of an explosive eruption. The Aviation colour Code (ACC) was raised to Orange and the Volcano Alert Level (VAL) was raised to Watch. A pilot reported an ash plume rising as high as 10.4 km (34,000 ft) a.s.l., and the Worldwide Lightning Location Network detected lightning associated with the cloud. The ACC was raised to Red and the VAL was raised to Warning. The eruption lasted about 73 minutes.
Cleveland | Chuginadak Island (USA) : AVO reported that no significant volcanic activity at Cleveland was detected in seismic, infrasound, or satellite data during 10-16 May. The webcam recorded some gas plumes during 13-14 May. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.
Colima | Mexico : On 12 May the Centro Universitario de Estudios e Investigaciones de Vulcanologia – Universidad de Colima reported that during the previous week seismic data revealed 26 high-frequency events, 21 long-period events, 2.5 hours of tremor, 12 landslides, and three low-intensity explosions.
Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 10-16 May ash plumes from Dukono rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted in multiple directions as far as 150 km.
Ebeko | Paramushir Island (Russia) : KVERT reported that an ash plume from Ebeko was identified in satellite images drifting about 50 km NE on 7 May. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Ibu | Halmahera (Indonesia) : Based on analyses of satellite imagery and information from PVMBG, the Darwin VAAC reported that during 10-11 May ash plumes from Ibu rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted E and SW. An ash plume on 16 May rose to 1.5 km (5,000 ft) a.s.l.
Karangetang | Siau Island (Indonesia) : Based on analyses of satellite imagery, wind data, and ground-based visual observations, the Darwin VAAC reported that on 10 May a gas-and-steam plume, possibly containing ash, rose from Karangetang to an altitude of 3.6 km (12,000 ft) a.s.l. and drifted over 35 km SE.
Kilauea | Hawaiian Islands (USA) : HVO reported that the lava delta at Kamokuna (the ocean entry area at Kilauea), which had been growing since late March, collapsed on 3 May. Two large cracks parallel to the coast were visible on 27 April, suggesting instability. Between 0935 and 0940 on 3 May a large steam plume appeared in the middle of the lava delta in the area of large cracks. Weak fountaining or spattering likely occurred initially, because new tephra deposits were visible in the steaming area; that activity ended by 0940. Images acquired over the next 25 minutes showed a progressively weaker steam plume, and a subsiding delta. Photos of the ocean entry taken on 7 May showed multiple streams of lava flowing into the ocean. During 10-16 May 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, from a vent high on the NE flank of the cone, 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 near the pali.
Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that ash plumes from Klyuchevskoy were identified in satellite images drifting 270 km SE and NW during 5-6 and 10-11 May, respectively. A weak thermal anomaly was noted on 5 and 10 May. 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 and wind model data, the Darwin VAAC reported that during 10-14 May ash plumes from Langila drifted N, NW, and S at altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l.
Nevado del Ruiz | Colombia : Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 9-15 May seismicity at Nevado del Ruiz continued to indicate unrest; the number and magnitude of events were higher compared to the previous week. Significant amounts of water vapor and gas continued to be emitted. Gas, steam, and ash plumes rose 1.7 km above the crater rim on 12 May and drifted NW and SW. According to the Washington VAAC the Bogota MWO reported an ash emission on 13 May. The Alert Level remained at III (Yellow; the second lowest level on a four-colour scale).
Reventador | Ecuador : During 10-16 May IG reported a high level of seismic activity at Reventador including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions. Steam, gas, and ash plumes rose as high as 700 m above the crater rim during 10-12 May. Crater glow was noted during 11-12 May.
Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that during 8-14 May explosive activity at Sabancaya slightly decreased from the previous week, with an average of 38 explosions detected per day. The number of long-period events continued to increase, while hybrid events were sporadic. Gas-and-ash plumes rose as high as 4.2 km above the crater rim and drifted more than 40 km NE, E, and SE.
Sinabung | Indonesia : Based on PVMBG observations, webcam and satellite images, and wind data, the Darwin VAAC reported that during 10-16 May ash plumes from Sinabung rose to altitudes of 3-4.9 km (10,000-16,000 ft) a.s.l. and drifted E and NE.
Suwanosejima | Ryukyu Islands (Japan) : Based on JMA notices and satellite-image analyses, the Tokyo VAAC reported that on 10 May plumes from Suwanosejima rose to an altitudes of 2.7 km (9,000 ft) a.s.l. and drifted E.
Turrialba | Costa Rica : OVSICORI-UNA reported an explosion at Turrialba on 10 May, followed by weak and passive ash emissions during 10-11 May. Several long-period earthquakes were recorded, and inflation continued. Gas measurements indicated a sulfur dioxide flux of 1,000 tons/day, and a high carbon dioxide/sulfur dioxide ratio. An event at 0900 on 12 May generated a plume, though poor visibility prevented a height estimate. An event at 0730 on 14 May generated a plume that rose 500 m above the crater rim and drifted N. Low-amplitude tremor was detected during 15-16 May, and a discontinuous ash plume rose no more than 500 m and drifted N and NW.