Выявленные с помощью методов фотограмметрии изменения морфологии конуса вулкана Ключевской и ревизия других последствий извержений 1984-1985, 1944-1945 и 1994 гг. позволили по-новому проинтерпретировать ранг и геолого-геоморфологический эффект этих событий. Показано, что их видимый "катастрофизм" обусловлен крупными (0.006 км3-2.12.1985 г. и 0.05 км3- 1.01.1945 г.) обвалами привершинной части вулкана, а возникшие отрицательные формы - типичные шарра, в понимании А. Риттманна. Извержение вулкана Ключевской 1.01.1945 г. нельзя считать пароксизмальным, поскольку не было характерных для такого типа его извержений массового выброса юве-нильной пирокластики и резкого прекращения эруптивной активности.

The first results of tephrachronological researches of the Sarychev Peak volcano, the Matua Island, (Central Kuriles) are represented including the reconstruction of its eruptive history in the Holocene. Based on the study of the distribution of petrogenous oxides and microelements in the tephra sampled layer-by-layer from the reference section of soil-pyroclastic cover of Matua Island, a general trend of the geochemical evolution of the volcano products during the Holocene epoch is traced, their typification was made. The horizons of the transition ashes were identified.

The article provides data on historical events of the Kurile island arc’s most active Peak Sarychev Volcano, Matua Island, the Central Kuriles. During the study period the volcano was producing short terminal eruptions of explosive and explosive-effusive types discharging volcanites chiefly with pyroclastic flows and related formations.

Data are presented on a moderate effusive-explosive eruption of the summit crater of Alaid volcano (Atlasov Island, Northern Kuril Islands) observed from September 10 to December 1, 2022. Based on satellite and visual data, it was found that as a result of Strombolian-Volcan activity two lava flows, 2.6 and 1 km long, were poured out on the southern slope of the volcano, and at least 16 emissions occurred to a height of 2.5 to 6 km a.s.l. The ash plumes spread out mainly in the southeast and east-southeast directions, their maximum length reaching 300–500 km. The eruption posed a danger to local airlines. The lava outpouring provoked the formation of lahars that descended the southern slope of the volcano and reached the island coast. The alluvial fan formed from mudflow masses partially deposited beyound the coastline, causing an increase in the island land.

The results of electrical exploration works in the area of Pauzhetsky and Nizhne-Koshelevsky geothermal deposits are presented. In 2012 y. works by VES method were carried out on the profile, crossing structures of Pauzhetsky deposit which were defined earlier. Sounding was made in 35 spots. In 2013 electrical exploratory works by VES method were carried out in the area of Nizhne-Koshelevsky geothermal deposit. Souding was made in 17 spots. Preliminary data of apparent resistance allocation to depth were drawn by results of the works. The areas permeable for hydrothermal liquors or gas-vapor heat-transfer were defined.