В работе представлены новые данные об игнимбритах, распространённых в верховьях реки Кавыча (Восточная Камчатка). Уточнены северо-восточные и северные границы области распространения игнимбритов. Изучен 500-метровый разрез вулканогенной толщи, в котором выделено 16 слоёв различных пород, главным образом игнимбритов. Они детально опробованы, сделаны и описаны шлифы каждого слоя, выявлены особенности их минерального состава, получены данные по валовому химическому составу.

The study of present-day hydrothermal ore-forming process in Uzon caldera (Kamchatka, Russia) is reported. The structure of ore body and the distribution components are described. Parameters of ore-forming process (temperature, pH, Eh and activity of dissolved hydrogen sulfide) are measured with original experimental devices. Parameters of gas and liquid phase flow and heat of hydrothermal fluid are studied in details. Base on this investigation results, the thermodynamic model of ore-forming process in Uzon caldera is designed. This model includes several ore-forming mechanisms: boiling, cooling and mixing and oxidization of hydrothermal solution. The analysis of thermodynamic simulation results of is compared with the data on mineralogical data and concentration of forms of sulfur that has allowed establishing a role of various ore-forming factors in ore deposition. The new model of hydrothermal ore process which explains formation of the full ore structure as consequence of self-development of thermal solutions is offered. Calculated concentration of the dissolved forms of sulphur and ore components are in the good consent with the natural data. Results of the spent works can be useful at research of hydrothermal deposits and modern geothermal systems.

We determined an isomorphic group of compounds with common formula K3Cu3(Fe3+, Al)O2(SO4)4 in products from fumarole activity of the Great Tolbatchik Fissure Eruption (GTFE, Kamchatka, 1975-1976). Within the isomorphic group, based on Fe and Al concentration we distinguished members on both sides of nominal 50 mol.% border. This fact along with variations in typical and diagnostically important physical characteristics of minerals was a factor for us to divide the group into two mineral species. Fe-members we called as "klyuchevskite", while Al-members were called as "alumoklyuchevskite". The latter is an aluminum analogue of klyuchevskite, compared to which Al is predominantly placed in Fe3+ positions.

By means of world’s volcanoes eruptions database periodicity of volcanic process in separate areas of suburb of Pacific Ocean and for separately taken volcano is revealed. It has appeared that the revealed periods are close to the periods of seismic process: T1 ≈ 198±17, T2 ≈ 2T1 ≈ 376±12 and T3 ≈ 4T1 ≈ 762±17 years. "Parity" of these periods can testify to "isolation" of suburb of Pacific ocean. Existential distribution of volcanic activity within suburb of Pacific Ocean was studied. It has been shown, that volcanic eruptions with W ≥ 4 (the volume of erupted is material 0.01 км^3 and more) for last 12 thousand years tend to migrate clockwise in the direction from New Zealand to the South America with a speed about 10 km/year, confirming earlier received results.