Based on visual and satellite data, the authors provide information that characterizes the volcanic activity in the Kuril Islands in 2018. Ebeko (Paramushir Island, the Northern Kurile Islands) and Sarychev Peak (Matua Island, the Central Kurile Islands) volcanoes were active in the Kuril Islands. Ebeko Volcano produced a weak (to moderate) explosive eruption in form of steam and ash-gas emissions (about 800 emissions at a height from 2 to 5.5 km). Sarychev Peak activity was characterized by a weak (to moderate) explosions (over the period from September till October the volcano produced at least 10 emissions that reached a height of 2 to 4.5 km). Due to the relatively low emission height and low ash concentration, the activity on Ebeko and Sarychev Peak in 2018 did not pose a serious threat to the international air routes, but could have a certain impact on the local airlines.

The paper presents data on the petrography, chemical and mineral composition of magnesian basalts (MgO content may reach 9 mass %) of Men'shii Brat volcano (Medvezh'ya caldera, Iturup Island, The Kuril Island Arc). The content of magnesian basalts and andesitic basalts in the front and axial zones of the Kuril Island Arc is very low. The article provides detailed data on the chemical composition of the rock-forming and accessory minerals (olivine, plagioclase, orto- and clinopyroxene, chromous spinel). High magnesian content, a peculiar composition of minerals (insets), olivine (Fo89-92) and chromous spinel (Kmg»50) associations allow concluding that the initial melts have a primitive nature.

The data on geology, petrography, mineralogy and petrochemistry for Kamen, Volcano in the central Kamchatka depression are presented. A study of the volcano's rocks and comparison with rocks of neighboring active volcanoes of the Klyuchevskoi group allow the establishment of some relationships. The rocks and minerals of Kamen, and Ploskie Sopki volcanoes show systematic differences in the chemistry of rocks and minerals such that they obviously could not be formed from the same primary melts. The rocks of dykes and Kamen' stratovolcano on one hand and the rocks of the Klyuchevskoi Volcano on the other hand form differently directed trends on petrochemical diagrams and differ in their compositions of rock-forming minerals, such they also could not originate from the same primary melts. The lavas of the monogenetic cones of Kamen' Volcano and moderately magnesian basalts of Klyuchevskoi Volcano are derivates of the same melts, i.e., the cones situated on the slopes of Kamen' are cones of Klyuchevskoi. The rocks of Kamen' and Bezymyannyi stratovolcanoes form a single narrow trend in all petrochemical diagrams in which the lavas of Bezymyannyi Volcano show a silica-rich branch, thus indicating a genetic relationship between these two volcanoes.