Report on Karymsky (Russia) — 30 March-5 April 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
30 March-5 April 2005
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2005. Report on Karymsky (Russia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 30 March-5 April 2005. Smithsonian Institution and US Geological Survey.
54.049°N, 159.443°E; summit elev. 1513 m
All times are local (unless otherwise noted)
During 25 March to 1 April, seismicity at Karymsky was above background levels, with 110-500 daily shallow earthquakes. Possible ash-and-gas explosions rose to 1,000-1,500 m above the crater (8,300-10,000 ft a.s.l.) Explosions occurred from two craters at the volcano's summit on 29 March, sending E-drifting ash-and-gas plumes to 1 km above the crater (8,300 ft a.s.l.). Karymsky remained at Concern Color Code 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.