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The Myauchan ore field located in the Omsukchan zone of the Okhotsk-Chukotka Volcanic Belt is described. The Korennoe and Malyutka Ag-Pb-Zn ore occurrences forming this field are localized at the center of anticlinal fold of NW strike made up of Upper Triassic carbonate-terrigenous deposits intruded by stock-like bodies and dikes of Upper Cretaceous andesite, monzodiorite, granite-porphyry, and rhyolite-porphyry. Sulfide-carbonate-fluorite-quartz veins and vein-veinlet zones with arsenopyrite, pyrite, sphalerite, galena, chalcopyrite, and Ag-tetrahedrite are localized both in intrusions and in terrigenous strata. The field bears As-Sb-Ag-Pb-Au-Bi-Cu-Zn-W mineralization. Study of fluid inclusions and REE and ore element patterns show that the field ores formed from chloride solutions with the participation of surface waters in hydrothermal-magmatic system under epithermal conditions. The ores were deposited from solutions with TDS = 0.5-9.0 wt.% NaCl equiv. in the temperature range 106-287 ºC. The ores containing ca. 70 ppm Ag and up to 1.2% Pb formed through boiling-off of solutions enriched in iron salts. The ores with Ag < 7 ppm and Pb ≤ 25 ppm were generated from diluted hydrothermal solutions with predominant sodium salts and potassium admixture. Mineralization of the Myauchan ore field marks the upper level of the Ag-Pb-Zn ore system similar to the Gol’tsovoe deposit.

We studied geochemical compositions of the early Paleocene basaltic and andesite dikes associated to linear zones of the Lankovo-Omolon shearing system (Northern Okhotsk region) and basalts of the Evdyreveem volcanic field associated to the Okhotsk-Penzhinsk fault system, and compared them to other synchronous manifestations of basic volcanism: andesibasalts and andesites of the studied earlier Garmanda field, as well as with the Late Cretaceous basalts of the Mygdykit Formation of the Northern Okhotsk region, roofing the Okhotsk-Chukotka volcanic belt. The isotopic composition of Sr and Nd in dikes, the distribution of major and trace elements with the ratios of noncoherent elements indicate the formation of volcanic bodies in the environment of continental margin rifting, which is confirmed by the combination of depleted, intraplate and above subduction geochemical features of their composition. Such behavior of the elements indicates multi-stage processes of the earlier Mesozoic supra-subduction fluid metasomatosis. Melting of an ancient buried Cretaceous slab may explain the appearance of such “above subduction” marks as the Nb-Ta negative anomalies in the studied basaltoids. Andesite dikes are characterized by higher isotope ratios of Nd and lower Sr, with lower absolute concentrations of trace elements and more pronounced anomalies on spider plots.

We report results of a systematic paleomagnetic study of the Abinskaya Group of the Kuznetsk depression, including a typical volcanic complex that reflects important features of the evolution of the Permian-Triassic Siberian large igneous province (LIP). Four zones of magnetic polarity have been established in the group’s deposits. We revise the correlation of the volcanic sheets of the Mal’tsevo Formation (Fm.) at the base of the group with the Ivakinsky Fm. of the Norilsk region, which is linked to the initiation of trap magmatism. The beginning of the eruption of the Saltymak complex volcanic rocks in the Kuznetsk area corresponds to the boundary between subchrons LT1n.1n and LT1n.1r (251.2 Ma) within the Kedrovka sub-formation of the Mal’tsevo Fm. This boundary was traced in the magnetostratigraphic sections of the Maimecha-Kotui, Koltogor-Urengoy, Western Taimyr, and Norilsk regions of the Siberian LIP and suggests a correlation of the Mal’tsevo Fm. volcanic rocks with the upper part of the undifferentiated interval of the Onkuchak - Tyvankit (?) Fms., the base of the Korotchaev Fm., the Verkhnetam Fm. and the top of the Samoed Fm. The duration of this main pulse of volcanism in the Kuznetsk depression did not exceed 0.1 Myr. The volcanic sheets of the second, significantly weaker pulse of the Yamin Fm. are compared with the Maimecha Fm. of the Maimecha-Kotui area and the top of the Korotchaev Fm. of the Koltogor-Urengoy area. Thus, the accumulation of the entire Abinskaya Group, including the sedimentary complex of the Sosnovka Fm., lasted no more than 1.5 Myr. Except for the initial stage, this coincided with the eruption of most of the Maimecha-Kotui and Koltogor-Urengoy trap sections. The early magmatism of the Ivakinsky time and its analogs in other areas of the Siberian province during the Permian-Triassic boundary in the Kuznetsk depression probably corresponds to the break between the Tailugan Fm. and the Abinskaya Group. The mean paleomagnetic pole (PLat = 59.0°, PLon = 160.3°, A95 = 5.7°, N = 33) calculated for the entire studied section reflects the paleogeography of the Kuznetsk depression and can be considered a reference pole for the Permian-Triassic boundary.

This study presents the results of recent regional seismic exploration and deep drilling efforts in the Sayan-Yenisei syneclise and adjacent areas of the Lena-Tunguska petroleum province. These results were used to build a series of structure maps for Riphean, Vendian and Lower Cambrian reflectors; thickness maps of the Riphean and Vendian terrigenous geoseismic sequences within the syneclise, and a tectonic map of the Vendian-Paleozoic structural stage of the Sayan-Yenisei syneclise. The proposed oil and gas geological zoning of the Sayan-Yenisei potential petroleum area enabled us to identify eight potential petroleum regions and perform a quantitative assessment of the hydrocarbon potential. The original in-place resources of the Sayan-Yenisei potential petroleum area are estimated to be 3 billion 231 million tons of hydrocarbon equivalent, including 3 trillion 39 billion m³ of gas and 192.7 million tons of condensate. It is shown that over next 15-20 years, up to 1 trillion m³ gas reserves can be explored in the Sayan-Yenisei potential petroleum area. It is proposed to consider the Boguchany village as a large gas conversion and helium production center.

In bottom sediments of the New Siberian sedimentary basin and adjacent geostructures of the East Siberian Sea, we identified СН₄, as well as its limit and unsaturated homologues (up to and including C₅H₁₂), CO₂, CO, H₂, He, H₂S, O₂, N₂, and Ar. Isotope-gas-geochemical parameters δ¹³С СО₂, СН₄ and С₂Н₆, of the molecular mass of hydrocarbon fraction and genetic coefficients indicate the presence of both syngenetic and epigenetic gases of various gas sources in sediments, including recent sediments, peatlands, coal-bearing and gas-bearing formations, solid bitumen, igneous formations, accumulations of gas hydrates and prognostic condensate-gas, condensate, oil-and-gas and gas-and-oil reservoirs. Concentrations of CO₂ and CO reach 29.25 and 0.06 cm³/kg, CH₄ and the sum of its homologues - 5.93 and 0.031, Н₂ and He - 0.78 and 0.318, H₂S - 0.092 cm³/kg; this indicates that gas-geochemical anomalies, exceeding the anomaly criteria by 6-124 times, form in bottom sediments. The formation and distribution of abnormal concentrations of natural gases depend on the complex influence of gas-controlling factors - geological structure, fold and fault tectonics, magmatism, coal-oil-gas content, bituminous content, organic saturation, lithological composition, water-physical and reservoir properties of sediments, hydrogeological, geocryological and other conditions for accumulation of natural gases or their degassing.

Investigating Early Eocene and Paleocene deposits within the Punjab Platform, Pakistan, involved comprehensive analysis using advanced geochemical and petrophysical techniques. This study evaluates the source potential of three formations: Nammal and Sakesar of Early Eocene age and Dungan and Ranikot of Palaeocene age. The Sakesar Formation, a reservoir rock, was evaluated through interpretation of wireline logs to estimate key petrophysical properties-porosity, water saturation, and hydrocarbon saturation. Geochemical investigations focused on total organic carbon content and Rock-Eval pyrolysis of twenty-one cutting samples from a well. These samples displayed TOC values ranging from 0.21 to 2.04 wt.% and S2 values ranging from 0.09 to 2.14 mg HC/g rock. Analysis positioned all samples within the immature window zone with Type II/III and Type III kerogen, suggesting limited generative potential. Findings suggest limited hydrocarbon generation from these formations. Petrophysical analysis indicated average porosity of 11.2%, water saturation of 32.58%, and hydrocarbon saturation of 67.42% for the Sakesar Formation, categorizing it as average to good reservoir potential. This study highlights complex geochemical and petrophysical characteristics of these formations. While Sakesar shows promising reservoir qualities, significant hydrocarbon generation potential from Nammal, Dungan, and Ranikot formations is constrained. Informed decision-making is crucial when considering these formations as hydrocarbon sources.

The kinetics and mechanism of hydrogen evolution on the MoSi₂ electrode in x M H₂SO₄ + (0.5-x ) M Na₂SO₄ ( x = 0.50; 0.35; 0.20) solutions have been studied. The cathodic polarization curves of MoSi₂ in the studied solutions are characterized by Tafel region with a slope of (-0.070)±0.002 V. The reaction order of the cathodic process with respect to hydrogen ions at the potentials of Tafel region is ~1.0; the derivative of the electrode potential with a change in electrolyte acidity is ~0.072 V. The impedance spectra of the MoSi₂ electrode in the studied potential range have the shape of a semicircle located in the capacitive half-plane, with the centre in the region of positive values of the imaginary impedance component; in the region of the highest frequencies, a short straight section is recorded on the impedance plots, indicating the presence of pores in the surface layer of the electrode. To describe the hydrogen evolution reaction on MoSi₂, we used an equivalent electrical circuit, the Faraday impedance of which consists of series-connected charge transfer resistance ( R₁) and a parallel R₂C₂Z_d-chain responsible for the adsorption of atomic hydrogen on the surface and its diffusion into the depth of the electrode material. The equivalent circuit also includes the solution resistance (R_s) and the double layer capacitance impedance, which is modeled by the constant phase element CPE₁. It is shown that the hydrogen evolution reaction on molybdenum disilicide in a sulphuric acid electrolyte proceeds along the discharge - recombination route with a quasi-equilibrium discharge stage when the Temkin logarithmic isotherm for adsorbed atomic hydrogen is fulfilled. The hydrogen evolution reaction is complicated by hydrogen absorption proceeding in the mode of solid-phase diffusion kinetics.

Physicochemical foundations for the technology of nitrogen acid processing of serpentinite from the Karakalpak deposit with the formation of pure magnesium nitrate and magnesium-containing compound fertiliser are developed. The chemical and mineralogical composition of serpentinite from the Karakalpak deposit is studied. As determined by X-ray diffraction analysis, microscopic and thermogravimetric studies, serpentinite sample contains clinoenstatite, pyrope, spinel, magnetites and other minerals with various crystal structures. Data on the extraction of serpentinite components in nitric acid by decomposition under different conditions (temperature, duration, nitric acid concentration) are presented. The subsequent stages of nitric acid extract processing have been carried out: removal of silica residue, ammonisation of the filtrate in order to precipitate undesirable impurities to obtain magnesium nitrate. The process of evaporation and crystallization of the filtrate to obtain pure magnesium nitrate has been studied.

The content of the main groups of biologically active substances in the flowers, leaves, rhizomes of Iris setosa cultivated under the conditions of the forest-steppe zone of the Novosibirsk Region has been determined. The content of tannins, pectins, protopectins, catechins, flavonoids, carotenoids during the seasonal development of plants was determined. It is found that tannin content in the leaves in all phenophases of I. setosa plant development is 6.3-8.5 times higher than in rhizomes. During the flowering period, flavonoid content in the leaves is 29.7 times higher than in rhizomes, during the stage of blossom fading it is 18.1 times higher, and at the stage of fruiting it is 25.1 times higher. The same accumulation of catechins (0.23-0.24 wt%) was found in underground and aboveground organs during the period of blossom fading. Pectin content in leaves during fruiting was detected to be 2.4-2.7 times higher than during flowering and blossom fading. Pectin content in rhizomes is 2.2-2.4 times higher during blossom fading and fruiting than during flowering. The content of carotenoids in flowers during flowering is 2 times higher than in rhizomes, but 2.6 times lower than in leaves. It is noted that the quantitative content of biologically active substances in the organs of I. setosa is determined by the peculiarities of growth and development during the seasonal period.

Pilot-scale tests results and laboratory studies of fire-resistant hydraulic fluid based on the developed hydraulic concentrate Hydrotol-ITCh HFAE are presented. Stable operation and operating parameters preservation of the developed hydraulic fluid physicochemical properties under the real conditions on a contaminated hydraulic system of a mining industry enterprise are shown. It was found that during six months of operation, the range of pH values, electrical conductivity, concentration and bacteriological purity did not change significantly, while the concentrate refilling, as well as the use of special disinfectants and cleansers, was not required. For the first time, the microbial composition of hydraulic fluid exposed to operation in the powered supports of the enterprise was studied using the method of metagenomic sequencing. Molecular genetic methods revealed a wide range of bacterial associates with various types of metabolism, including anaerobic sulphate-reducing bacteria involved in the biological corrosion of metals.