Data showing the activity of the volcanoes in the Kurilе Island Arc in the XXI century are given. The volcanic eruptions at the volcanoes Chikurachki, Chirinkotan, Ebeko, Sarychev Peak, Ekarma, Ivan Grozny, Alaid and Snow were considered. Increase of steam-gas activity was observed at the volcanoes Sinarka (Shiashkotan Isl.), Berg (Urup Isl.), Severgin Peak (Kharimkotan Isl.) and Kudryavy (Iturup Isl.). It is shown that the brief (from a few hours to several days) explosive eruptions of weak and moderate intensity (VEI = 0–3) prevailed. The most active were volcanoes Chikurachki (8 events) and Ebeko (4 events) (Paramushir Isl.). The strongest eruption during the reporting period was explosiveeffusive eruption of Sarychev Peak volcano in 2009; the longest were effusive eruptions of Snow Volcano (Chirpoi Isl.) in 2012–2016. The total volume of erupted material for the years 2000–2016 does not exceed 0.3–0.4 km3.

Обсуждаются новые данные о распределении ртути во вмещающих вулканогенно-осадочных и магматических горных породах, гидротермально-метасоматических породах и всех типах современных новообразований (гидротермальных глинах, аргиллизированных почвенно-пирокластических отложениях, кремнистых и лимонит-гематитовых плащах, донных осадках, солевых выпотах различного состава, и др.), характерных для зоны гипергенеза геотермальных месторождений. На примере Нижне-Кошелевского (пародоминирующего) и Паужетского (водного типа) геотермальных месторождений, термальных полей Кошелевского вулканического массива и Камбального вулканического хребта (Южная Камчатка) показано значение ртути как элемента-индикатора температуры, фазового состояния и динамики гидротерм, интенсивности процессов аргиллизации пород, относительного возраста (зрелости) геотермальных месторождений и термоаномалий.

Выполнены морфоструктурные, геологические, геофизические и газогеохимические исследования на восточном склоне хребта Вернадского, прилегающем к г. Северо-Курильску (о. Парамушир). Показано строение участков локализации близповерхностных и глубинных термальных вод. Полученные данные имеют принципиальное значение для создания концептуальной и разведочной моделей Северо-Курильского геотермального месторождения и понимания механизмов формирования современной рудной минерализации в недрах гидротермально-магматической конвективной системы.

Based on the integrated investigation, the authors obtained data on granulometric, chemical and mineral composition of ashes from the March — April, 2017 Kambalny Volcano eruption.
The data showed that the ash is resurgent, and it consists of the hydrothermally altered andesites from the Kambalny Ridge being the volcano bedding rocks. The authors suggest that the seismic build-up prior to the eruption and the 2017 explosive eruption were caused by the renewed gas-and-hydrothermal processes in the basement rocks of the Kambalny Ridge.

The article provides the analysis of the published data on anomalies of iridium and other platinum-group elements (PGE) at different Phanerozoic stratigraphical levels and gives evidences of heterogeneity of these anomalies and arguments of different authors about their relation with impact, volcanic, paleoclimatic and biotic events. Most of iridium anomalies coincide with large extinctions of sea organisms. The authors revealed in Cretaceous paleoceanic deposits of Eastern Kamchatka (Kamchatsky Mys peninsula) PGE anomalies at two levels corresponding to oceanic anoxic events OAE2 and MCE.

The authors studied siliceous limestones from the Vetlovsky complex of the Vakhil rise (Eastern Kamchatka). The paper provides their lithological and geochemical characteristic. The new limestones were compared with the previously studied limestones from the Albian-Cenomanian Smagin association of the Kamchatsky Mys peninsula, as well as with Cretaceous carbonates from the Pacific underwater rises. Limestones from the Vetlovsky complex deposited in the pelagic environments at low sedimentation rates, and under oxidizing conditions. Terrigenous input in deposits was insignificant. According to the geochemical data, some layers of limestones contain pyroclastics of various composition, which indicate a deposition in the area of island arc volcanism effect. The sedimentation occurred on the oceanic intraplate volcanic rise or on the internal rise of backarc basin. The major part of siliceous-carbonate oozes were forming between depths of 1-1.5km.