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We study the relations between several selected elements present in the Sin Quyen IOCG deposit, Lào Cai, North Vietnam, and interpret the obtained correlations, especially with a coefficient higher than 0.7. The correlations with high coefficients are mainly observed for the elements belonging to the chalcophile group (Cu, Ag, Au, Te, and Bi) and for the relation between uranium and Ag, Au, Cu, Pb, and Bi. Although the S-, Fe-, and REE-bearing minerals are predominant in the studied deposit, no strong correlation between them and the other elements was observed, even with Cu. The phenomena are primarily explained based on the geochemical properties of the mentioned elements and the characteristics of IOCG deposits.

The composition of the organic matter (OM) of coals in the Ulug-Khem Basin has been studied. According to Rock-Eval pyrolysis data, this OM is a type III kerogen, sometimes significantly oxidized. The coal of low-grade metamorphism has a high hydrocarbon potential. Based on the gas-liquid chromatography and chromatography-mass spectrometry data on the distribution of n-alkanes, isoprenoids, polycyclic biomarkers, and aromatic hydrocarbons, we have established the composition of the primary OM of the coals and the grade of OM metamorphism. The primary OM of the coals consists mainly of remains of aquatic vegetation and terrigenous OM. The latter includes conifer remains, which are identified from the presence of 4β(H)-19-norisopimarane in the aliphatic fraction of bitumen and from the domination of retene over cadalene and 6-isopropyl-1-isohexyl-2-methylnaphthalene in the aromatic fraction.

This paper presents an alternative variant of stratigraphic subdivision of the upper Riphean-Vendian deposits (approximately corresponding to the Neoproterozoic Erathem of the International Chronostratigraphic Chart (ICC)) of the Bashkir Mega-Anticlinorium (BMA), based on the modern concepts of changes in the biosphere, atmosphere, and hydrosphere (and, accordingly, in the climate and the course of sedimentary processes) in the period ~1000-540 Ma, with regard to the results of recent studies and the proposals for improving the Russian General Stratigraphic Scale (GSS) of the Precambrian. The strict necessity of subdividing chronostratigraphic and lithostratigraphic units is shown. The presented data give grounds to regard the Zil’merdak Formation as a Group and assign three of its lower formations to the Middle Riphean (Yurmatinian). It is shown that the period of accumulation of the Karatau Group (comprising the Katav, Inzer, Min’yar, and Uk formations) was significantly shorter than the duration of the Late Riphean (Karatavian). Special attention is focused on the age of the Uk Formation (analysis of the existing data made it possible to refine its stratigraphic position): It formed, most likely, in the period 780-740 Ma. A high uncertainty of the stratigraphic position of the overlying geologic bodies is demonstrated. The Bakeevo, Tolparovo, Suirovo, and Kurgashla formations must be regarded as part of the Terminal Riphean (Arshinian). The Arsha Group, comprising the Bainas, Makhmutovo, Igonino, and Shum formations in the Tirlyan trough and represented by the Krivaya Luka Formation in the Krivaya Luka syncline, should not be totally assigned to the Terminal Riphean. It is proposed to exclude the Bakeevo Formation and the Tolparovo-Suirovo sequence from the Asha Group, because these deposits are, most likely, a modification of the Arsha Group located on the western flank of the BMA. The Uryuk Formation is probably of pre-Vendian age. The current contradictory data on the stratigraphy of the supra-Uryuk unit of the Asha Group are interpreted. The ages of the geologic bodies composing the Group and its stratigraphic interval still call for a thorough study.

We studied the middle Cambrian unit of the Kuonamka Formation section on the Kyulenke River (Siberian Platform) and performed its biostratigraphic subdivision based on trilobites. The middle Cambrian section has intervals corresponding to the regional zones of the Amginian Stage. Six levels with mass accumulation of fauna remains have been revealed: Two levels are located within the Ovatoryctocara Zone; the third level is at the boundary between the Ovatoryctocara and Kounamkites zones; the fourth layer is confined to the roof of the Triplagnostus gibbus Zone; and the fifth and sixth levels are located within the Tomagnostus fissus-Paradoxides sacheri Zone. The composition of rocks and bitumens of their organic matter (OM) has been studied, including the geochemical specifics of the mineral components of rocks (iron, sulfur, and СО2) and of saturated hydrocarbons of bitumens as well as noncarbonate carbon isotopes in the OM. It has been established that the OM sedimentation took place under normal aeration of the sea basin waters, without hydrogen sulfide contamination of the bottom waters. The intensity of chemical and biochemical transformations of mineral and organic components during diagenesis was controlled by the contents of organic carbon and sulfate ion, the activity of the anaerobic prokaryote community, and the rate of sediment mineralization. We have also established relationships between the content of organic carbon in potentially oil source rocks and the contents of iron oxide, total sulfur, and sulfide and sulfate sulfur as well as the ratios of saturated hydrocarbons. The alternation of highly carbonaceous black shales and carbonaceous rocks is apparently due to a change in the composition of biologic communities of microorganisms (sources of hydrocarbon biomarkers) and in the intensity of OM transformation during diagenesis. We assume that the OM transformation included sulfate reduction and dealkylation of high-molecular steroids in the unconsolidated OM-enriched marine sediments with the participation of bacteria. The intensity of these processes depended on the mass of the primary OM, the amount of sulfate ion, and, hence, the pH and Eh of the medium.

The paper presents new data on the upper Silurian litho- and biostratigraphy of the Gorny Altai area. Sediments within this interval store a succession of taxonomically representative middle-upper Ludfordian, lower Pridoli, and Lower Devonian (Lochkovian-Pragian) conodont assemblages. The new fauna constraints made a basis for updated correlations of the local and regional stratigraphic units at the Silurian/Devonian boundary of Gorny Altai with the stages of the International Stratigraphic Chart. The correlation results reveal a mismatch between the boundaries of the local and regional Silurian units and the respective boundaries of stages in the International Stratigraphic Chart.

The article proposes a method for selecting stable feature points of images obtained using the BRISK and AKAZE algorithms. The method is based on the selection of points that remain in the image after its significant transformation. The results of numerical experiments, based on 1000 images, confirming the effectiveness of the proposed method are presented. It is found that the sets of points obtained using the proposed method contain three to five times more stable points than random sets of the same size. It is shown that, for the selection of stable points, it is more efficient to use significant transformations of images.

The properties of the method for testing the hypothesis of theindependence of random variables based on the use of a nonparametric pattern recognition algorithm corresponding to the maximum likelihood criterion are investigated. The distribution laws in the classes are estimated on the basis of the initial statistical data, assuming the independence and dependence of the compared random variables. Under these conditions, the estimates of the probability of an error in pattern recognition in classes are calculated. Based on their minimum value, a decision is made on the independence or dependence of random variables. The application of the proposed technique allows us to circumvent the problem of decomposition of the range of values of random variables into multidimensional intervals. The effectiveness of the proposed technique with the complication of the relationship between random variables and changes in the volume of the initial statistical data is investigated by the method of computational experiments.

The article presents the structure and implementation of a digital model of a coalmine face. The digital model contains the parameters of the coal seam, the technical parameters of the mining machines, and economic indicators. The digital model can be used to support decision-making to increase the productivity of the coalmine face and to assess the effect of using new mining machines or new technology. An example of using the digital model to determine the dependence the financial indicators of functioning of the face on the face length and technological schemes of coal mining is given.

The article is devoted to the development of a numerical algorithm for determining the optimal regime parameters of a chemical process. The statement of the problem of multi-purpose optimization of the chemical process conditions is formulated in the general form. To solve this problem, a genetic algorithm is presented. The algorithm is based on the FFGA method, which allows one to determine many Pareto-optimal solutions. A computational experiment is carried out for the thiol aminomethylation reaction in order to determine the optimum temperature and reaction time, ensuring the maximum conversion of the starting materials and the maximum selectivity of the formation of the target reaction product.

The paper suggests an approach to the construction of equipment for diagnostics of dangerous states caused by destruction of bearing elements in propulsion systems like gas-turbine engines. The approach is based on continuous monitoring of external factors affecting the bearing assembly and of the presence of metal particles in the engine lubrication system, which are carried out using original single-coil eddy-current sensors, modeling of the wear of bearings, and expert verification of the remaining resources in changing operating conditions. This makes it possible to determine the residual life of the bearing assembly and predict the time until its intensive destruction. Thus, the possibility of taking measures to prevent the development of emergency situations is provided.