The February-July 2007 Eruption of the Summit Crater of Klyuchevskoi Volcano, Kamchatka

摘要

Observations of the summit eruption of Klyuchevskoi volcano in the period from February 15, 2007to July 9, 2007 are considered. This typical (for this volcano) summit eruption was explosive–effusive in char-acter. The ejectamenta volume is estimated at 0.025 km3. Calculation of active phases of the volcano was car-ried out in accordance with V.A. Shirokov's technique. The identified active phases agree well with the eruptiveperiods. The 2007 summit eruption corresponds to an active phase (May 2006 to May 2009) favorable for thevolcano's eruption. Geodetic observations carried out since 1979 along a radial profile have revealed uplifts andsubsidences of the northeastern slope of the volcano. The maximum displacement of 23 cm was recorded in2007 on the site closest to the volcano crater at a distance of 11 km from the summit crater center. In the courseof two previous summit eruptions (2003-2004 and 2005) insignificant uplifts and subsidences of the slope werealso noted, although the general ascent of the slope remained. This indicated possible repeated eruptions in thenearest future. Changes in the seismicity before, during and after the eruption are also discussed.