Roundup of Global Volcanic Activity – Ongoing Activity for the week of 19 April – 25 April 2017
Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 16-17 April ash plumes from Bagana rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted N, SE, and S. Plumes drifted 55-85 km during 19 and 23-24 April.
Bezymianny | Central Kamchatka (Russia) : KVERT reported that during 14-21 April lava continued to advance down the NW flank of Bezymianny’s lava dome. A thermal anomaly was identified in satellite images during 14-17 April. The Aviation colour Code remained at Orange.
Bogoslof | Fox Islands (USA) : On 19 April AVO noted that no new volcanic activity at Bogoslof had been detected in satellite, seismic, or infrasound data since a short-lived increase in seismicity on 15 April; AVO lowered the Aviation colour Code to Yellow and the Volcano Alert Level to Advisory.
Cleveland | Chuginadak Island (USA) : AVO reported that recent satellite images of Cleveland revealed that a lava dome has been extruded in the summit crater, with growth likely beginning after the last explosion on 31 March. The Aviation colour Code was raised to Orange and the Volcano Alert Level was raised to Watch.
Slightly elevated surface temperatures were identified in satellite images over the past couple of weeks. The new dome was first visible in images on 15 April, with the presence of a small (less than 10 m diameter) mound deep in the crater. By 23 April this mound had grown to 45 m in diameter. Dome growth had occurred with no detectable seismicity.
Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 19-25 April ash plumes from Dukono rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NE, E, and SE.
Ebeko | Paramushir Island (Russia) : KVERT reported that on 14, 16, and 19 April several explosions at Ebeko were observed by residents of Severo-Kurilsk (Paramushir Island) about 7 km E. Ash plumes rose as high as 3.2 km (10,500 ft) a.s.l. Minor amounts of ash fell in Severo-Kurilsk on 18 April. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Kilauea | Hawaiian Islands (USA) : During 19-25 April 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. A growing lava delta is building where the lava enters the water. Surface lava flows were active above the pali.
Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly was detected over Klyuchevskoy during 14-17 and 23 April. A steam-and-gas plume that rose to 5 km (16,400 ft) a.s.l. and drifted 125 km SW on 23 April contained some ash, prompting KVERT to raise the Aviation colour Code to Orange. On 24 April satellite images showed an ash plume drifting 72 km SW at an altitude of 7 km (23,000 ft) a.s.l. On 25 April KVERT noted that activity had significantly decreased and only steam-and-gas emissions were observed. The Aviation colour Code was lowered to Yellow. On 25 April ash was again present in a plume; KVERT raised the Aviation colour Code to Orange. The plume rose 3-4 km (9,800-13,100 ft) a.s.l. and drifted 60 km SW.
Sabancaya | Peru : Based on webcam images, satellite views, and seismic data the Buenos Aires VAAC reported sporadic gas-and-ash puffs from Sabancaya during 18-25 April, sometimes rising as high as 8.2 km (25,000 ft) a.s.l.; clouds sometimes hindered observations of the volcano.
San Miguel | El Salvador : In a special report from 17 April, SNET reported an increase in seismicity and gas emissions from San Miguel in recent days. Earlier that day during 0620-0630 RSAM values spiked to 356, an increase over normal values around 50. During 18-21 and 23-24 April RSAM values fluctuated between 80 and over 300.
Sheveluch | Central Kamchatka (Russia) : KVERT reported that during 15-21 April lava-dome extrusion onto Sheveluch’s N flank was accompanied by strong fumarolic activity, dome incandescence, ash explosions, and hot avalanches. Satellite images showed a thermal anomaly over the dome during 13-17 April, and an ash plume that drifted 95 km E on 15 April. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Sinabung | Indonesia : Based on PVMBG observations, satellite images, and wind data, the Darwin VAAC reported that during 20-22 and 24 April ash plumes from Sinabung rose to altitudes of 3.3-4.3 km (11,000-14,000 ft) a.s.l. and drifted SW and E.