Report on Sheveluch (Russia) — 3 November-9 November 2010
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 3 November-9 November 2010
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2010. Report on Sheveluch (Russia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 3 November-9 November 2010. Smithsonian Institution and US Geological Survey.
56.653°N, 161.36°E; summit elev. 3283 m
All times are local (unless otherwise noted)
KVERT reported that moderate seismic activity from Shiveluch was detected during 29 October-5 November and a thermal anomaly over the volcano was observed in satellite imagery. Seismic data on 31 October, and 1 and 4 November suggested that ash plumes rose to an altitude of 5.8 km (19,000 ft) a.s.l. Satellite imagery showed ash plumes drifting 400 km SE on 31 October and 1 November. Fumarolic activity was seen during 1-2 November. Cloud cover prevented observations the other days.
On 1 November, pyroclastic flow deposits from the large explosive eruption on 27 October were detected in satellite imagery on the ESE flank, and had traveled 15 km. Volcanologists inspected the deposits the next day and found that the pyroclastic flow had annihilated a forest in the Bekesh River valley. More than half of the lava dome edifice was destroyed during the eruption. The Aviation Color Code level remained at Orange.
During 4-9 November, the Tokyo VAAC reported that ash plumes from possible eruptions were observed in satellite imagery drifting N, SE, and S at altitudes of km (15,000-25,000 ft) a.s.l.
Geologic Background. The high, isolated massif of Sheveluch volcano (also spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group. The 1300 km3 volcano is one of Kamchatka's largest and most active volcanic structures. The summit of roughly 65,000-year-old Stary Shiveluch is truncated by a broad 9-km-wide late-Pleistocene caldera breached to the south. Many lava domes dot its outer flanks. The Molodoy Shiveluch lava dome complex was constructed during the Holocene within the large horseshoe-shaped caldera; Holocene lava dome extrusion also took place on the flanks of Stary Shiveluch. At least 60 large eruptions have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Widespread tephra layers from these eruptions have provided valuable time markers for dating volcanic events in Kamchatka. Frequent collapses of dome complexes, most recently in 1964, have produced debris avalanches whose deposits cover much of the floor of the breached caldera.