Report on Karymsky (Russia) — 25 October-31 October 2006
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 25 October-31 October 2006
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2006. Report on Karymsky (Russia) (Sennert, S, ed.). Weekly Volcanic Activity Report, 25 October-31 October 2006. Smithsonian Institution and US Geological Survey.
54.049°N, 159.443°E; summit elev. 1513 m
All times are local (unless otherwise noted)
Seismic activity increased at Karymsky during 21-27 October, with 350-550 shallow earthquakes occurring daily. Explosions produced ash plumes that may have reached altitudes of 2.5-5.0 km (8,200-16,400 ft) a.s.l. and drifted E, NE, and SE. Staff from the Institute of Volcanology and Seismology (IVS) observed a series of ash bursts that produced plumes to 2.0 km (6,600 ft) a.s.l. on 25 October. A thermal anomaly in the crater was detected on satellite imagery during 19-24 October.
Geological Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The caldera enclosing Karymsky formed about 7600-7700 radiocarbon years ago; construction of the stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been vulcanian or vulcanian-strombolian with moderate explosive activity and occasional lava flows from the summit crater.