The Kekuknai massif was formed in the course of tectono-magmatic activity that involved the origin of a shield volcano and a caldera depression with associated emplacement of extrusions that terminated in intense post-caldera areal volcanism. The mineralogical compositions of the massifs rocks have been considered in detail. The use of previously known and newly developed indicator properties of rock-forming minerals allowed the reconstruction of the general picture of the magmatic melt evolution and conditions of rock crystallization (various fluid and water saturation levels, as well as the oxidation state of the system). Essentially island-arc or intraplate characteristics of the massif s rock compositions are found at different stages of development of a single fluid-magmatic system. Decompression evolution of the parent deep-seated basanitic magma occurred via occurrence in intermediate magma chambers of daughter magmas of trachybasalt (pre-caldera stage) or hawaiite (areal volcanism) composition. Subsequent emanate-magmatic differentiation of these melts, combined with crystallization differentiation under changing P-T-f0l conditions, resulted in the formation of the entire diversity of the Kekuknai rocks

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.

Изучены два вулканических центра в пределах Срединного хребта Камчатки - Южный и Северный Черттук. Рассмотрены морфология и строение шлаковых конусов и лавовых потоков, особенности состава их пород. Подсчитаны объемы изверженного материала для обоих центров (>2 км3 каждый). Впервые получены С-датировки (-3550 л.н.) для Южного Черпука и приведены данные о предполагаемом возрасте (-1740 г. н.э.) Северного Черпука. Обсуждается проблема генезиса указанных вулканических центров.