Report on Karymsky (Russia) — 27 September-3 October 2006
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 27 September-3 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, 27 September-3 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 data and satellite observations reported by KVERT indicated that moderate ash eruptions of Karymsky continued during 23-29 September. Weak local shallow earthquakes occurred at a rate of 100-250 per day. Ash explosions were thought to have risen to about 4.5 km (14,800 ft) a.s.l. on 22 September, and up to 2.5 km (8,200 ft) a.s.l. on the other days of that week. A thermal anomaly over the volcanic crater was noted on 23 and 26-27 September. The Level of Concern Color Code remained at Orange.
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.