RECENT LARGE-SCALE DOWNFALLS ON THE CONE OF KLYUCHEVSKOI VOLCANO: A REVISION OF THE CONSEQUENCES OF THE EVENTS OF 1944-1945, 1984-1985, AND 1994

Abstract

The photogrammetric measurements of the morphological changes in the cone of Klyuchevskoi Volcano and the revision of the other consequences of its 1944-1945, 1984-1985, and 1944 eruptions resulted in the reinterpretation of the rank and geological and geomorphological effects of these events. It is demonstrated that the visible "catastrophism" of these eruptions was due to large-scale (0.05 km3 on January 1, 1945 and 0.06 km3 on December 2, 1985) collapses of the summit part of the cone, the resultant negative forms being typical sharras in the sense of A. Rittmann. The eruption of January 1, 1945, cannot be considered paroxysmal, for there was neither massive ejection of juvenile pyroclastics, nor abrupt cessation of the eruptive activity, typical of this type of Klyuchevskoi eruptions.