Glacial balance observations and the information of meteorological network were used to reconstruct a long-term mass balance of Kozelsky and Grechishkin glaciers (Avachinsky volcanic group and mountains Ostraya and Khuvkhoytun). The mean annual balance of both glaciers is negative and equals 30 and 38 g/cra , respectively, for the last 40 years. From the beginning of the sixties favourable climatic conditions for glacial development of Kamchatka were observed, which caused the transgression of Kozelsky glacier in 1972-76 and the deceleration of degradation rate of Grechishkin glacier.
Besides that the regime of the crater glaciers of Mutnovsky volcano was examined (analysed). The accumulation of solid precipitation reaches here 3000 mm per year. The measured mass balance of North-eastern and Southwestern glaciers in 1980 were 29 and 23 g/cm2 respectively. Presently, this volcano is active and has a positively influence on the crater glacier regime. The area of crater glaciation has increased by 0.4 km2 or 17% since the major eruption in 1945.

Long-continues field, and air- and space-borne studies of Kamchatkan volcanoes carried out within the framework of the International Russian-American project "Earth Sciences". In conjunction with the use of deep seismic sounding observations, yielded materials of remote sounding which have been mostly processed for the Klyuchevskoy volcanic cluster, this being the most active and productive in Kamchatka. For the first time ever,
a digital map of volcanoes of the Klyuchevskoy cluster to scale 1 : 100000 has been made. All cinder cones were superposed on the map in a system of coordinates with special indication of the cinder cones in the regional zone of areal volcanism and the eruptive centers of bocca eruptions on Klyuchevskoy volcano along with their petrochemical characteristics and ages. This paper also provides information on the "single primary" magma
of Klyuchevskoy Volcano.