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Saline waters (up to 22 g/l) were tapped by deep (to 3000 m) wells at the foot of active volcanoes Avachinsky and Koryaksky, within Avachinsky depression. Temperature of waters was ~ 60°C in the western part and cold in the eastern part, closer to the Pacific coast. In this paper we present the literature and our own data on chemical and isotopic composition of these waters. The waters are of the Na-Cl type with extremely low abundances of sulfate and magnesium, high concentration of calcium and surprisingly high concentration of strontium. The waters contain about 50 ml/l of gas where methane and nitrogen are main components (~ 70 vol% and 30 vol%, respectively) and also presents H2S (~ 30 ml/l) and very low concentrations of CO2 (< 0.5 vol%). The N2/Ar ratio, as a rule, is higher than the air ratio, i.e., the non-atmospheric nitrogen presents. We discuss the possible options of the water-rock interaction, responsible for the chemical composition of waters, and offer a conceptual model of the proposed basin of mineral waters that includes the distribution of deep temperatures, the location of the possible sources of heat mineralized solutions.

The "AIRES" Shared Research Facilities (SRF) is a high-tech laboratory complex based on the Institute of Precambrian Geology and Geochronology RAS (IPGG RAS, St. Petersburg). The Institute conducts geological, mineralogical, geochronological, isotope-geochemical and paleontological studies aimed at solving the problems of the formation and evolution of the Earth's continental crust in the Precambrian and Phanerozoic. The methodological developments of the "AIRES" SRF make it possible to interpret the conditions of occurrence of igneous, metamorphic and sedimentary rocks and minerals, as well as their age. The ongoing research includes studies on geology, geodynamics, stratigraphy, petrology, lithology, isotope geochemistry, geochronology, as well as paleogeography, archeology, soil science, ecology, and chemistry.

A summary of the latest data on isotope geochemistry of the lunar rocks shows that their silicon, oxygen and refractory metals isotopic composition are no different from terrestrial one, indicating a single source of origin of both Earth’s and Moon’s substances. At the same time, the isotopic signature of the volatiles along with rubidium, zinc, gallium, potassium, iron in lunar rocks is fractionated considerably, showing heavy isotope enrichment compared to Earth’s ones. Kinetic isotope effect, underlying this phenomenon, occurs during the process of lava degassing when volatiles emits from the magma surface to the vacuum of space. Thus, conditions of the crystallization of lunar rocks deviate significantly from those of Earth.We consider the formation of the Moon following Marakushev’s fission theory. In the view of the theory, the Moon has been spun from proto-Earth, while a necessary impulse moment reached due to a proto-Earth’s initial fluid veneer. This event dates to approximately 50 Ma from the moment of the Solar system formation and coincides with the beginning of the proto-Earth’s core impulse segregation. The future Moon consisted of the relatively light silicate material, but also included a portion of the proto-Earth mantle. Meanwhile, other reasonable hypotheses of the Moon formation, such as impact and evaporation theories, are powerless to explain all the peculiarities of the isotopic signatures of the lunar rocks as well as the genesis of the Galilean moons.

The data on C, O, Sr and S isotope composition of the carbonates, quartz and sulfides from the Tamunier and Vorontsovsk gold-ore deposits, localized in the Auerbakh volcano-plutonic belt are cited. It is established that on mineral isotope characteristics the nearest analogue of mineralization in beresites of the Tamunier deposit is the gold-polymetallic mineralization in jasperoids of the Vorontsovsk deposit. Calculation of the C, O and S isotope composition of the ore-bearing fluid testifies to a participation in ore-formation of two main substance reservoirs - the rock (sea carbonates and biogenic pyrite of host volcanogenic-sedimented series) and the fluid one (metalliferous magmatogene, as well as metamorphogenic fluids connected by the intrusive mass injection).