Report on Klyuchevskoy (Russia) — 15 October-21 October 2003
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 15 October-21 October 2003
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2003. Report on Klyuchevskoy (Russia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 15 October-21 October 2003. Smithsonian Institution and US Geological Survey.
56.056°N, 160.642°E; summit elev. 4754 m
All times are local (unless otherwise noted)
Seismicity was above background levels at Kliuchevskoi during 11-17 October, with one to six magnitude 1.6-2.1 earthquakes per day at depths of ~30 km. Nine shallow M 1.7-2.2 earthquakes were recorded along with many smaller ones. On 9, 10, and 11 October, gas-and-steam plumes with little ash rose to 0.5-1.5 km above the volcano's crater and extended more than 10 km E. Similar plumes on 12 and 16 October extended more than 46 km and 50 km to the E and NE, respectively. Strombolian activity was observed on the night of 10-11 October. Kliuchevskoi remained at Concern Color Code Orange.
Geologic Background. Klyuchevskoy (also spelled Kliuchevskoi) is Kamchatka's highest and most active volcano. Since its origin about 6000 years ago, the beautifully symmetrical, 4835-m-high basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. It rises above a saddle NE of sharp-peaked Kamen volcano and lies SE of the broad Ushkovsky massif. More than 100 flank eruptions have occurred during the past roughly 3000 years, with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks of the conical volcano between 500 m and 3600 m elevation. The morphology of the 700-m-wide summit crater has been frequently modified by historical eruptions, which have been recorded since the late-17th century. Historical eruptions have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters.