Report on Sheveluch (Russia) — 19 May-25 May 2010
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 19 May-25 May 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, 19 May-25 May 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 during 14-21 May seismic activity from Shiveluch was above background levels, suggesting that possible ash plumes rose to an altitude of 5.1 km (16,700 ft) a.s.l. Satellite imagery revealed a large daily thermal anomaly from the lava dome. An ash plume drifted about 40 km SE on 15 May and gas-and-steam plumes drifted the same distance NE on 18 May. Based on information from KVERT, the Tokyo VAAC reported that on 24 May an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted NE. Ash was not identified on satellite imagery. The Aviation Color Code level remained at Orange.
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.