Report on Klyuchevskoy (Russia) — 30 May-5 June 2007
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 30 May-5 June 2007
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2007. Report on Klyuchevskoy (Russia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 30 May-5 June 2007. Smithsonian Institution and US Geological Survey.
56.056°N, 160.642°E; summit elev. 4754 m
All times are local (unless otherwise noted)
KVERT reported on 1 June that the Level of Concern Color Code for Kliuchevskoi was lowered from Red to Orange. During 25 May-1 June, seismic activity continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. According to video data and visual observations on 27 and 31 May, there was Strombolian and Vulcanian activity at the summit crater, lava flows, and phreatic bursts on the NW flank from where lava interacted with ice. Ash plumes rose to altitudes of 5-7 km (16,000-26,200 ft) a.s.l. during 29-31 May and drifted in multiple directions. Strong phreatic bursts were seen from the front of a new lava flow from on the E flank on 31 May.
Based on information from KVERT, the Tokyo VAAC reported that ash emissions produced plumes on 2 and 5 June to an altitude of about 5.8 km (19,000 ft) a.s.l. Ash was not identified on satellite imagery. During 3-4 June, ash plumes to altitudes of 5.2-7 km (17,000-23,000 ft) a.s.l. were possibly identified on satellite imagery.
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.