pdf № 369, September

DOI: 10.19110/geov.2025.9.1

The kinetic characteristics of hydrocarbon formation by organic matter of natural series domanik rocks with different levels of maturation and domanik rocks after a series of autoclave experiments at different temperatures are studied. The work uses a method for calculating the realization of hydrocarbon potential for a series of rocks that takes into account the previous thermal history of organic matter. It is shown that the calculation of the realization of hydrocarbon potential based on the kinetic characteristics of immature rock for high stages of domanik organic matter transformation is incorrect starting from a certain level of thermal maturity, which is determined by changes in the chemical structure of kerogen due to oil generation. The data presented in this work indicates this change level a 50 % degree of transformation of the organic matter of the source rock.

Keywords: Domanik shale, autoclave, experiment, kinetics of oil formation, kinetics of thermal treatment of organic matter, kinetic characteristics

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DOI: 10.19110/geov.2025.9.2

The article presents the results of the carbonate reservoirs permeability and porosity model detailing of the oil field in the Timan-Pechora oil and gas province in relation to their formation features and secondary changes. The object of study is Upper Carboniferous — Lower Permian carbonate reservoirs. The resulting model shows the spatial localization of different lithological types of reservoir rocks, as well as the effect of fracturing on the permeability. The relevance of this study conditioned by the fact that the modeling results are the basis for identifying prospect areas for production level ensuring in the Upper Carboniferous reservoir.

In the course of the study, the classification of reservoir rocks according to core data is carried out; the distribution of various lithological types of limestone in the area and in the section has been established; the predominant type of voidness and the characteristic range of filtration and capacity properties for each selected lithological type have been determined. In addition, fractures are classified according to core data and reservoir microimages, the relationship between the fracturing density and the rock bulk density and primary porosity has been established, and the positive effect of fracture paragenesis on the permeability of low-capacity reservoirs has been confirmed.

Keywords: carbonate reservoirs, fracturing, Dunham classification, void structure, Timan-Pechora oil and gas province

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DOI: 10.19110/geov.2025.9.3

Based on electron microscopic studies of ooid limestones from the Lower Permian section of the Southern Timan, morphological features have been identified that indicate the formation of carbonates as a result of organomineralization processes caused by the presence and activity of microorganisms (microbial metabolism) and the influence of mucous substances acting as a matrix for crystal nucleation and growth. As a result of the research, mineralized bodies of organisms, biogenic microstructures, bacterial biofilms and filaments preserved in various forms have been identified. The obtained novel data testify to organomineralization at the formation of fossil ooids.

Keywords: carbonates, limestones, ooids, organomineralization, diagenesis, biogenic microstructures

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DOI: 10.19110/geov.2025.9.4

The significant intensification of negative natural phenomena in mountainous areas in recent decades has increased the urgency of ensuring the safe maintenance of tailings storage facilities for the mining industry. The article examines the situation at the tailings storage facility of the Tyrnyauz Mining and Processing Complex. During the research, modern monitoring technologies were implemented, enabling the acquisition of highly reliable data in real-time. As part of the work, vulnerable areas and sections prone to washout risk were identified. As protective measures for the main dam to prevent failure, options have been proposed to ensure the design discharge capacity of the drainage tunnel and to restore the operational functionality of the open emergency spillway channel.

Keywords: tailings pond, mudflow, environmental disaster, monitoring, toxic waste

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DOI: 10.19110/geov.2025.9.5

The article discusses two forms of the table of 27 symmetry species (without cubic syngony): the L_i4 axis has its own row, and other inversion axes are forbidden; all possible inversion axes are used. The latter case is particularly interesting when comparing the species of symmetry with smooth geometric interpretations (cones and cylinders) of the limiting Curie symmetry groups. It is proposed to distinguish 14 rather than 7 classes of symmetry. The article discusses their nomenclature with a historical overview.

The article teaches the creative assimilation of fundamental results, their derivation, and comprehension in detail. It is intended for teachers, postgraduate students, and students (geologists, geographers, biologists, etc.) studying the basics of crystallography in a geometric variant without group theory and linear algebra. The article is dedicated to Professor A. I. Glazov, the last representative of the E. S. Fedorov — A. K. Boldyrev — I. I. Shafranovsky crystallographic school at the Leningrad Mining Institute (now the Saint Petersburg Mining University), and is accompanied by unique photos from the personal archive of Professor D. P. Grigoriev.

Keywords: symmetry species and classes of crystals, compositions of symmetry elements, true and false inversion axes, limiting Curie symmetry groups.

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