Roundup of Global Volcanic Activity – New Activity for the week of 25 October – 31 October 2017
Agung | Bali (Indonesia) | 8.343°S, 115.508°E | Elevation 2995 m
On 29 October PVMBG lowered the Alert level for Agung to 3 (on a scale of 1-4), noting a decline in activity, especially since 20 October. The thermal anomaly in the crater identified in satellite data was less intense in October than in September. Beginning on 20 October GPS data showed a slower deformation rate. Seismic signals decreased in number and amplitude, though low-frequency events continued to indicate magma movement. White fumarolic plumes rose as high as 500 m above the crater rim during 20-29 October; a comparison of video taken by drones on 20 and 29 October showed a relative decrease in the intensity of fumarolic emissions. BNPB stated that, despite the decreased Alert Level, the exclusion zones remained intact (at 6 km, and an additional expansion to 7.5 km in the NNE, SE, S, and SW directions). The number of evacuees was 133,457 (spread out in 385 shelters).
Aoba | Vanuatu : Based on analyses of satellite imagery and model data, the Wellington VAAC reported that on 29 October ash plumes from Aoba rose 6.1 km (20,000 ft) a.s.l. and drifted S and SE.
Kirishimayama | Kyushu (Japan) : JMA reported that during 25-31 October activity at Shinmoedake (Shinmoe peak), a stratovolcano of the Kirishimayama volcano group, continued to be slightly elevated. White plumes rose 100-500 m above the crater rim, though weather clouds sometimes prevented visual observations. Almost daily field surveys revealed no particular changes in the fumarolic and fissure areas near the cracks on the W flank of Shinmoedake, nor to the thermally anomalous zone below the crack. Sulfur dioxide fluxes were as high as 200 tons/day. The Alert Level remained at 3 (on a scale of 1-5).
Sarychev Peak | Matua Island (Russia) : SVERT reported that a thermal anomaly over Sarychev Peak was identified in satellite images on 29 October. Weather clouds prevented observations on the other days during 24-30 October. The Aviation colour Code remained at Green.
Tinakula | Solomon Islands : Based on satellite data and information from ground-based observers, the Wellington VAAC reported that during 25 October and the early part of 26 October a low-level eruption at Tinakula was ongoing. Ash emission rose 2.1 km (7,000 ft) a.s.l. and drifted S and SE. A news article from 1 November noted that significant ashfall had covered crops, and the water supplies for an estimated 11,500 people had been contaminated.