Report on Karymsky (Russia) — 23 July-29 July 2008
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 23 July-29 July 2008
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2008. Report on Karymsky (Russia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 23 July-29 July 2008. Smithsonian Institution and US Geological Survey.
54.049°N, 159.443°E; summit elev. 1513 m
All times are local (unless otherwise noted)
KVERT reported that seismic activity at Karymsky was above background levels on 18, 19, and 23 July and at background levels during 20-22 and 24-25. Explosive activity that produced ashfall was seen by area volcanologists. Interpretation of the seismic data suggested that on 19, 21, and 23 July possible ash-and-gas plumes rose to altitudes of 3 km (10,000 ft) a.s.l. Observations of satellite imagery revealed a thermal anomaly in the crater during 19-21 July. The Level of Concern Color Code was raised to Orange.
Based on information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 25 July an ash plume rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted NE.
Geologic Background. 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.