Fluid regime and ore water of bitumo-hydrothermal mineral associations in the conditions of Western Donetsk graben

Abstract

The fluid regime of bitumen-hydrothermal mineral associations on the ore fields of the Western Donetsk graben, which are part of the Dnieper-Donetsk paleorift, has certain geochemical features. It is conditioned by the peculiarities of geological development, structure and the current level of tectonic activity of the region. The purpose of the article is to study the fluid regime of bitumen-hydrothermal mineral associations and the participation of hydrocarbons in the hydrothermal process. The research methodology consisted of a theoretical interpretation of laboratory studies, in particular chemical analyzes of rocks, ore minerals, bitumen, groundwater and gases, as well as isotopic analysis of carbon of solid bitumen. Research results. Field studies have found that bitumen-hydrothermal mineralization in the rocks is naturally timed to tectonically activate anticlinal structures. The energy source of its formation are the polychronous processes of heat-and-mass transfer, the power of which is determined by the tectonic activity of the zones of deep faults. In the rocks of the region, with the specified type of ore mineralization (mercury and mercury-polymetallic), the halo waters of a certain geochemical specialization are formed, which include chemical elements of ore and impure minerals and bitumen, as well as endogenous fluids. Among such fluids is the carbon of solid hydrocarbon compounds, the isotopic composition of which indicates its inorganic origin. The presence of bitumen-hydrothermal mineral associations of chemical elements and gases in halo waters of deep origin indicates that hydrothermal systems of the ore fields of the Western Donetsk graben are on the modern, post-hydrothermal stage of development. The scientific novelty of the material presented in the article is based on several substantive theoretical conclusions, which are based on the actual material of the research carried out by the authors. The natural affinity of bitumen-hydrothermal associations to tectonically activate structures located in the zones of deep faults has been proved. The affinity of inorganic carbon bitumino-hydrothermal mineral associations in solid bitumen and chemical elements present in gas jets and groundwater to metamorphic and mantle processes (He, H2, Hg, CO2, CH4, Li, Rb, Cs, etc.) is substantiated. , which are manifestations of modern tectonic activity of alpine tectogenesis. It was substantiated that the formation of the chemical composition of the halo waters of bitumen-hydrothermal mineral associations is provided both by exchange chemical processes in the system mineral-water-gas and by the income of fluids of deep genesis. The practical significance of the work is conditioned, on the one hand, by the use of ore hydrothermal mineralization in the rocks as a criterion for the search of hydrocarbon accumulations, and on the other hand, by the prediction of the possibility of hydrocarbon compounds upcoming from large depths in which, in abnormal thermodynamic conditions, an inorganic synthesis of hydrocarbons takes place.