This paper examines the Karymsky Volcanic Center to estimate how much volcanic and hydrothermal activity affects the chemical composition of river water. We evaluate the volumes of major and trace elements coming to the Pacific Ocean via the Karymsky River. We assess the quality of river water in compliance with the regulations for potable water, water used for household work, and in fisheries. It is shown that the formation of ion load of the river water mostly occurs by inflow of thermal waters, as well as due to water-soluble complexes of ashes discharged by Karymsky Volcano and coming to the catchment area of the river. The annual volume of dissolved material transported by the river to the Kronotsky Bay of the Pacific Ocean amounts to more than 90 kilotons.

In 1975–1976 a remarkable volcanic eruption took place on the Kamchtka peninsula, part of the Soviet Union's arc of active volcanoes. Dr Fedotov and his colleagues studied the largest basaltic eruption in history, one of the most important volcanic events in the twentieth century. During this prolonged eruption they carried out extensive seismological, geophysical, geodetic and geochemical investigations. The results of this detailed and thorough investigation were collected as a series of papers under the editorship of S. A. Fedotov and collected into this volume, which was originally published by Cambridge in 1983. The result is a classic descriptive work of a major volcanic eruption.

This paper presents the results of visual observations, particle-size analysis, seismological observations, and acoustic measurements carried out during a small-magnitude eruption of Bezymyannyi in June 1986. A mlodel is proposed for the mechanism of the eruption. A specific character of the eruption is explained by a deeper localization of a gas-rich aagia portion in the conduit,