KIZIMEN VOLCANO, KAMCHATKA — A FUTURE MOUNT ST. HELENS?

Abstract

We studied the tectonic setting, morphology, geologic structure, history of eruptive activity and evolution of the composition of the erupted material of Kizimen volcano, Kamchatka, from the moment of its origination 11–12 thousand years ago to the present time. Four cycles, each 2–3.5 thousand years long, were distinguished that characterize the activity of the volcano. All of the largest eruptions were dated, and their parameters determined. We also estimated the volume and the mass of the erupted products, the volcanic intensity of eruption of material during periods of high activity, and the amount of material the volcano ejected at different stages of its formation. It has been shown that the evolution of the composition of the rocks erupted (from dacite to basaltic andesite) takes place as a result of mixing of dacitic and basaltic magma. It is suggested that future eruptions that may take place at Kizimen may be similar to those at Bandai (1888) and Mount St. Helens (1980) volcanoes.