Report on Karymsky (Russia) — 13 April-19 April 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
13 April-19 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, 13 April-19 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)
Seismic activity was above background levels at Karymsky during 8-15 April, with the number of shallow earthquakes increasing from 100 to 1,500 per day during the week. Possible ash-and-gas explosions may have reached 1 km above the crater (8,300 ft a.s.l.) during 12-13 April. Ash-and-gas plumes extended ~30 km on 8 and 9 April. Ash deposits extended ~10 km on the S side of the volcano. 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.