Based on observations from A.I. Malyshev, a new eruption . . . began in June with the extrusion of a block ~80 m high. From 22 to 29 June, a viscous lava flow ~500-550 m long poured out onto the E flank of the dome. During the night of 24-25 June two small pyroclastic flows were produced, with a volume of ~7.5 x 10⁵ m³ of material covering an area of ~0.25 km².

Further Reference. Maksimov, A.P., Firstov, P.P., Girina, O.A., and Malyshev, A.I., 1992, The Bezymianny volcano eruption in June 1986: Volcanology and Seismology, no. 1, p. 3-20 (in Russian); 1992, v. 13, p. 1-20 (in English).

Geological Summary. The modern Bezymianny, much smaller than its massive neighbors Kamen and Kliuchevskoi on the Kamchatka Peninsula, was formed about 4,700 years ago over a late-Pleistocene lava-dome complex and an edifice built about 11,000-7,000 years ago. Three periods of intensified activity have occurred during the past 3,000 years. The latest period, which was preceded by a 1,000-year quiescence, began with the dramatic 1955-56 eruption. This eruption, similar to that of St. Helens in 1980, produced a large open crater that was formed by collapse of the summit and an associated lateral blast. Subsequent episodic but ongoing lava-dome growth, accompanied by intermittent explosive activity and pyroclastic flows, has largely filled the 1956 crater.

Information Contacts: P. Firstov, A. Maksimov, and O. Girina, IV.