No 6 (2024)
Scientific articles
Oil and gas potential of the Triassic complex in Timan-Pechora province
Abstract
The article presents the results of the analysis of the Triassic oil and gas complex, the main parameters characterizing the reservoir capacity, the screening capacity of the seals, the composition and properties of the fluids.
The relevance of the chosen topic is determined by the fact that at present, the main direction of maintaining and developing oil production in the Timan-Pechora oil and gas province is still the development of new fields and the introduction of oil deposits in already developed areas.
It is shown that the Lower Triassic deposits are characterized by a complex structure both vertically and in area, which causes significant problems in the search for and exploitation of deposits. Oils characterized by high density and viscosity, are also often encountered. When planning and conducting geological exploration, it is necessary to take into account the structural features of the deposits confined to these deposits.
3-11
Gold mineralization of the interformational contact of Riphean and Devonian deposits (Tsilema uplift, Middle Timan)
Abstract
The article presents the results of studying native gold and the mineral composition of the heavy fraction of samples from the zone of interformational contact of the Middle Devonian and Middle Riphean deposits, opened by a ditch in the upper reaches of the Volchiy Creek (a tributary of the Tsilma River). Titanium and rare earth minerals predominate in the heavy fraction. Native gold is small (0.25—1.0 mm), with an ore appearance, a low degree of roundness and various forms. The Ag content in gold is up to 10.3 wt. %. Fineness is 899—1000 ‰. The internal structure of gold is heterogeneous and is characterized by a granular, block-mosaic structure. Inclusions of pyrrhotite, pyrite, galena and arsenopyrite are found in gold. The inclusion of pyrite in gold is similar in composition to the inclusion of pyrite in quartz. Gold is noted in intergrowths with quartz, less often muscovite. For the first time, gold intergrowth with rutile was found in the Middle Timan. Rutile has admixtures of V, Nb, and Fe. It is assumed that the primary sources of the studied gold are the zones of development of gold-quartz-sulfide disseminated mineralization, localized in the Riphean shale strata and intersecting quartz veins. The nature of the deposits, their mineral composition, morphology, and composition of gold of the studied interformational contact are similar to the complex diamond-gold-rare earth-rare metal-titanium paleoplacer Ichet'yu, which allows predicting the presence of similar ore objects not only within the Tsilema uplift, but also throughout Timan.
12-27
Image analysis of carbonate clastic rock thin sections using AI systems
Abstract
The paper deals with the application of machine learning and computer vision technologies for solving the problem of estimating the content of clastic component in carbonates based on thin sections. The training collection is represented by 122 monochrome micro-images of thin sections (fragments of 0.6 x 0.6 mm size) of slightly altered carbonate rocks, divided into two classes — without lithoclasts (lithoclasts are absent or occupy less than 10 % of the image area), with lithoclasts (lithoclasts occupy more than 30 % of the image area). When training the model for image classification, an accuracy of more than 90 % is achieved. The application of the model to the images of thin sections is implemented through console programmes using the Core ML framework. The programmes allow estimating the variations of the “distribution density” of lithoclasts along the profile through the thin section image and to construct a “map” of the distribution of areas with lithoclasts in the image. The resulting data can be used for comparison with geochemical and other numerically expressed information, as well as for selection of areas with the lowest content of allochthonous component in the thin section for the geochemical studies. The model in Core ML format is available upon request from the authors.
28-31
Targeted modification of the technological properties of mineral raw materials: new approaches and technologies Commemorating the 80th anniversary of B. A. Ostashchenko (1944—2008)
Abstract
To develop the ideas and innovations of Dr. (Geological and Mineralogical Sciences) Boris Andreevich Ostaschenko in the field of targeted modification of the properties of minerals, we studied of aluminum-containing raw materials and carbon-containing raw materials of plant origin. The main trends in the development of technological mineralogy, new approaches to technologies for predictive assessment of the quality of mineral raw materials, mining and other wastes for the adaptation of composite materials through post-structural modification are shown.
32-39
Chronicle, events, facts. History of Science
The world's first departmentof soil studies (dedicated to the 100th anniversary of the Leningrad school of soil studies)
Abstract
The key role of St. Petersburg (Leningrad) State University in the development of soil science as a science is undoubted. The founders of the scientific school of soil science at St. Petersburg State University (LSU) are P. A. Zemyatchensky, V. V. Okhotin, N. I. Prokhorov. It was at Leningrad State University that for the first time in the country, admission to the specialty “Soil Science” was opened. The world's first textbook “Soil Science” was published at Leningrad State University (1933). Over the years of its existence, the Department of Soil Science (hereinafter referred to as soil science and engineering geology) has trained more than a dozen highly qualified certified specialists.
40-43