Report on Klyuchevskoy (Russia) — 9 February-15 February 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 9 February-15 February 2005
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2005. Report on Klyuchevskoy (Russia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 9 February-15 February 2005. Smithsonian Institution and US Geological Survey.
56.056°N, 160.642°E; summit elev. 4754 m
All times are local (unless otherwise noted)
During 4-11 February, seismicity was above background levels at Kliuchevskoi and ash plumes rose above the volcano. On 6, 8, and 9 February, ash plumes rose ~2.5 km above the volcano's crater. Gas-and-steam plumes rose to ~3 km during 6-9 February. A cinder cone was noted in the volcano's crater on 6 February. Fresh ash deposits were seen on the SW flank of Ushkovsky volcano (NW of Kliuchevskoi) on 7 February, and in the town of Kluchi on 9 February.
During 31 January to 9 February, Strombolian activity occurred in the terminal crater of Kliuchevskoi and a lava flow traveled into Krestovsky channel on the volcano's NW flank. Phreatic bursts occurred in this channel when a lava flow contacted glaciers during 6-9 February. 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.