Report on Sheveluch (Russia) — 24 January-30 January 2007
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 24 January-30 January 2007
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2007. Report on Sheveluch (Russia) (Sennert, S, ed.). Weekly Volcanic Activity Report, 24 January-30 January 2007. Smithsonian Institution and US Geological Survey.
56.653°N, 161.36°E; summit elev. 3283 m
All times are local (unless otherwise noted)
Activity at Shiveluch continued above background levels during 19-26 January, with over 120 shallow earthquakes occurring daily. Based on seismic interpretation and observation and video data, gas-and-ash plumes rose to 5.5 km (18,000 ft) a.s.l. and avalanches occurred throughout the reporting period. Plumes drifted W and NW. Fumarolic activity from the SW flank was noted on 25 January. A large thermal anomaly was visible on satellite imagery. Based on satellite imagery, the Tokyo VAAC reported that ash plumes rose to an altitude of 4.6 km (15,000 ft) a.s.l. on 28 and 29 January and drifted SE.
Geological Summary. The high, isolated massif of Sheveluch volcano (also spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group. The 1,300 km3 andesitic volcano is one of Kamchatka's largest and most active volcanic structures, with at least 60 large eruptions during the Holocene. 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 occur on its outer flanks. The Molodoy Shiveluch lava dome complex was constructed during the Holocene within the large open caldera; Holocene lava dome extrusion also took place on the flanks of Stary Shiveluch. 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.