Geological Setting

Bezymianny is part of the Klyuchevskoy Group in the Central Kamchatkan Depression and is dwarfed by its much larger neighbors, Kamen and Klyuchevskoy. This volcanic region is located near the intersection of the nearly perpendicular intersection of the Aleutian arc with Kamchatka's Eastern Volcanic Front. The complex tectonics of this location have resulted in several theories for local magma generation.

Image from Google Earth

Photo of Bezyimianny Volcano by Izbekov, 2006

1956 Eruption and Subsequent Activity

Prior to 1955, Bezymianny volcano was assumed to be extinct. However, in 1955 the volcano showed signs of activity including seismicity, significant deformation, and moderate eruptions associated with the intrusion of a cryptodome. In 1956, Bezymianny underwent a catastrophic sector collapse that led to a paroxysmal direct blast and subsequent Plinian eruption quite similar to that recorded at Mt St Helens, Washington in 1980. Since 1956 activity at Bezyimianny has continued, including frequent eruptions and dome growth (sometimes taking a "nautilus" form). During the past approximately thirty years, Bezyimianny has experienced explosive eruptions one to two times per year. We hope that multi-faceted research on the volcano will result in a better understand of Bezymianny, the Klyuchevskoy Group, and the general dynamics of directed blast eruptions.

Photo of Bezyimianny Volcano by Gwyneth Hughes, 2006

Similarities to Mt St Helens

Bezymianny and Mt St. Helens have recently experienced remarkably similar eruptive histories.  Both had directed-blast type catastrophic eruptions (Belousov, 1996; Belousov et al. 2007) followed by subsequent small eruptions and the growth of a dome-like feature or whaleback within the crater (see pictures below).  PIRE is currently gather samples and putting in instumentation at Bezymianny volcano while collaborating with scientists studying Mt St. Helens in order to further compare the two volcanoes. For more information see "Twins Across the Pacific" poster and abstract

Photo of Mt St Helens Volcano by Glicken, 1982

Photo of Bezyimianny Volcano by Gorshkov, 1956