Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 7 November - 13 November 2018

Aira | Kyushu (Japan) : JMA reported that the sulfur dioxide emission rate at Minamidake crater (at Aira Caldera’s Sakurajima volcano) was high at 1,100 tons/day on 6 November, an increase from the previous measurement of 1,000 tons/day recorded on 23 October. Very small eruptive events were occasionally recorded during 9-12 November. The Alert Level remained at 3 (on a 5-level scale).

Dukono | Halmahera (Indonesia) : PVMBG reported that an event at Dukono, recorded by the seismic network at 0824 on 8 November, generated an ash plume that rose 200 m above the crater rim and drifted SW. The Darwin VAAC reported that during 12-13 November ash plumes rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted E and NE.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 2-9 November that sent ash plumes to 3.7 km (12,400 ft) a.s.l. Ash plumes drifted in multiple directions and caused ashfall in Severo-Kurilsk. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that 7-18 explosions per hour were detected at Fuego during 8-12 November. Ash plumes from the explosions rose as high as 1.1 km above the crater rim and drifted 8-20 km W and SW. Ash fell in areas downwind including Morelia (9 km SW), Santa Sofia (12 km SW), Sangre de Cristo (8 km WSW), Panimaché (8 km SW), El Porvenir, Finca Palo Verde, and San Pedro Yepocapa (8 km NW). Incandescent material was ejected 150-300 m high and caused avalanches that traveled far, reaching vegetated areas in multiple drainages. Lava flows as long as 1.2 km advanced in the Ceniza (SSW) drainage, though lava-flow activity greatly decreased by 12 November.

Kadovar | Papua New Guinea : According to the Darwin VAAC an ash plume from Kadovar was identified in satellite data on 9 November drifting WNW at an altitude of 1.8 km (6,000 ft) a.s.l.

Krakatau | Indonesia : PVMBG reported that four events at Anak Krakatau occurred between 1620 and 1710 on 9 November. Each event lasted for 42-55 seconds, based on the seismic data, and produced ash plumes that rose 300-500 m above the crater rim and drifted N. An event at 0939 on 10 November generated an ash plume that rose 500 m and drifted N. There were 10 events recorded during 1029-1656 on 12 November, each lasting 38-117 seconds, and producing ash plumes that rose 200-700 m and drifted N. Four events were recorded during 0546-0840 on 13 November, each lasting 44-175 seconds, and producing ash plumes that rose as high as 800 m. The Alert Level remained at 2 (on a scale of 1-4); residents and visitors were warned not to approach the volcano within 2 km of the crater.

Merapi | Central Java (Indonesia) : PVMBG reported that during 2-8 November the lava dome in Merapi’s summit crater grew slowly at a rate of 3,500 cubic meters per day, faster than the previous week. By 7 November the volume of the dome, based on photos from the SE sector, was an estimated 273,000 cubic meters. White emissions of variable density rose a maximum of 100 m above the summit. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to remain outside of the 3-km exclusion zone.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported a two-minute-long eruption at Rincón de la Vieja began at 1703 on 9 November. Weather conditions prevented webcam views and estimates of plume heights.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that an average of 18 explosions per day occurred at Sabancaya during 5-11 November. Hybrid earthquakes were infrequent and of low magnitude. Gas-and-ash plumes rose as high as 3.7 km above the crater rim and drifted 40 km N, NW, and W. MIROVA detected seven thermal anomalies, and on 8 November the sulfur-dioxide gas flux was high at 2,500 tons per day. The report noted that the public should not approach the crater within a 12-km radius.

Semisopochnoi | United States : AVO reported that three possible small explosions at Semisopochnoi were detected in infrasound data between 1951 and 2004 on 9 November. No associated ash clouds were observed in partly cloudy satellite images, and no other activity was noted during 7-11 November also in partly cloudy images. Images were cloudy during 12-13 November. The Aviation colour Code remained at Orange and Volcano Alert Level remained at Watch (both are the second highest levels on four-level scales).

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite data on 2 and 6 November. Explosions at 1510 on 9 November generated ash plumes that rose to 7 km (23,000 ft) a.s.l. and drifted 5 km NE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Turrialba | Costa Rica : OVSICORI-UNA reported that during 6-11 November low-level ash-and-gas emissions at Turrialba were continuous, though occasionally punctuated by energetic explosions which elevated the plumes as high as 500 m above the crater rim. The emission drifted towards the Valle Central. Ashfall was reported in several areas downwind including Cascajal de Coronado, Desamparados (35 km WSW), San Antonio, Guadalupe (32 km WSW), Sabanilla, San Pedro Montes de Oca, Moravia (31 km WSW), Heredia (38 km W), and Coronado (San José, 35 km WSW). Emissions likely continued on 12 November, though inclement weather did not allow for visual confirmation.

Veniaminof | United States : AVO reported that the eruption from the cone in Veniaminof’s ice-filled summit caldera, continued at low levels during 7-13 November. Satellite and webcam data showed elevated surface temperatures from minor lava spattering and lava effusion. Continuous low-amplitude tremor was recorded. Steam and diffuse ash plumes periodically identified in webcam and satellite images rose as high as 3 km (10,000 ft) a.s.l. and drifted S and W. Recent satellite data showed that the lava flows had traveled as far as 1.2 km from the vent. Fractures in the ice sheet adjacent to the lava flow continued to grow due to meltwater flowing beneath the ice sheet. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale) and the Volcano Alert Level remained at Watch (the second highest level on a four-level scale).