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Molecular simulations of CH4/CO2 competitive adsorption in moisture coals are carried out. The synergistic effect of micropore walls has a significant impact on the spatial distribution of adsorbates. Water molecules in micropores can prevent CO2 and CH4 from smoothly diffusing and adsorbing in the pore. The micropore is more favorable to the advantage of CO2 in the competitive adsorption. The variation of excess adsorption capacity is related to the density difference between adsorbed phase and free phase. Relative to CH4 density, CO2 density is easier to affect the variation trend of adsorption capacity in the competitive adsorption.

Detailed geologic information can be priceless for oil- and gas- oriented geologic exploration in Arctic aquatic basins. Exploration reports on coal basins and deposits located along the Arctic coast are highly detailed and can be used for reconstruction of facies and thermobaric conditions of the poorly explored offshore areas. The article summarizes information on the Russian Arctic coal basins geology: geological structure, tectonic settings, coalforming environments and coal quality parameters. Coal basins of the region contain not only brown and bituminous coals for energetics, but include valuable coking coal (Pechorskiy, Tungusskiy, Beringovskiy basins), anthracite, thermoanthracite and graphite (Taimyrskiy, Tungusskiy basins, Dolgozhdannoye deposit), related coal methane (Pechorskiy basin, coal deposits of Spitzbergen) and trace elements (Lenskiy basin, coal basins and deposits of Chukotka and Frantz Josef Land). It is also can be used for production of advanced materials (adsorbents, sunthetic graphites, etc).

The research results of rare and valuable metals and estimations of resources of these metals in the coal deposits of the Russian Arctic zone are presented. In coal deposits in the Arctic zone of Russia (Pechora, Lensky, Tungusky, Taimyrsky, Zyryansky coal basins, coal deposits of Chukotka, Kamchatka, Franz Josef Land) anomalous concentrations of trace elements (Sc, Ti, V, Ga, Ge, Sr, Y, Zr, Nb. Mo, Pd, REE, etc.) have been established. The metal contents in the coals of the Lensky and Zyryansky basins, the deposits of Kamchatka, and the Franz Josef Land are given. The results of electron microscopic studies of mineral inclusions (with local microanalysis for their diagnosis) of coals of the Russian Arctic are presented. The results of calculating the prognostic resources of TiO2, V2O5, Th, Y2O3, REE 2O3, Sc, Mo, Ga, and other metals in the studied deposits are given. It is shown that coal deposits of the Russian Arctic zone should be considered as an unconventional and promising source of valuable metals. It is necessary to conduct extensive studies of the metal content of coal basins and deposits in the Arctic zone of Russia and assess the geological resources of the valuable metals contained in them.

Based on the chemical model of coal, slit micropores with different pore sizes are established and structures are optimized in the software of materials studio. As the temperature rises, absolute adsorption capacities of H2O are slightly affected, while absolute adsorption capacities of CO2 and CH4 gradually decrease. As the fugacity rises, excess adsorption curves of CO2 experience increase-decrease-gentle three stages, while the curves of CH4 gradually decrease. With the increase of pore size, adsorption capacities of H2O increase, while adsorption capacities of CO2 and CH4 gradually decrease. H2O firstly adsorbs on the oxygen-containing functional group, so the walls of pore are the preferential area for H2O, while CO2 and CH4 choose to adsorb on–C–C–, therefore the walls are the primary area for CO2 and CH4. Strong potential in micropores and hydrogen bond among water molecules will promote the water adsorption, while the adsorptions of CO2 and CH4 are only induced by the Van der Waals interaction, but the difference between adsorption density and bulk density of CO2 and CH4 decides the change of excess adsorption capacity.

The main features of the transformation of organic matter (OM) in the greenschist, amphibolite, and granulite facies of metamorphism are considered based on the example of the Ukrainian crystal shield. The occurrence area and OM content in highly carbonaceous ancient rocks are characterized. The composition of primary sedimentary rocks and the processes of accumulation of biophile elements under the OM transformation are reconstructed.

Most coalbed methane (CBM) reservoirs contain moisture that can have an impact on adsorption and diffusion of CBM, so moisture content is an important factor that affects CBM production. CO2 can be used to improve CBM production on site. Combined with these two points, regulations of CH4 adsorption and diffusion are sought under different conditions when CO2 is injected into coal seams with moisture. Slit pores with different moisture contents (1%, 2%, 4%, and 6%) and random models are established. Molecular simulations are carried out, respectively, from 0 MPa to 10 MPa at 293.15, 303.15, and 313.15 K. Relative to CO2, the interaction of CH4 and −C–C– is weaker, indicating that CO2 can adsorb more steadily on the surface of coal. Water molecules preferentially adsorb on the oxygen functional groups, and then water molecules adsorb each other with hydrogen bonding to form clusters that can interfere with the adsorption and diffusion of CO2 and CH4. Because of the influence of functional groups, hydrogen b...

This paper reports the data on the uranium content in Dictyonema shale and phosphate rock in the Kaibolovo–Gostilitsy Area of the Baltic Basin (Leningrad Region). Specific features of the uranium ore in the studied area and stratigraphic rock sequence of the Early Ordovician Pakerort horizon are considered. A high uranium concentration in the Dictyonema shale layer has been determined, the correlation of uranium with other elements was defined, probable conditions of uranium ore genesis are described, and predicted uranium resources within the studied area are estimated.

The Pechora coal basin is considered to be one of the promising targets for the extraction of unconventional hydrocarbon raw materials – coalbed methane. Korotaikha depression is a structural subdivision of two basins – the Timano-Pechora oil and gas basin and Pechora coal basin. Currently, there is a favorable situation for the development of coalbed methane resources: on the one hand, the construction of new coal enterprises is postponed indefinitely, on the other hand, oil producing companies come with technologies close to the technologies for self-extracting methane from coal seams.The issue of perspective methane-coal fields of the Korotaikha depression in the Pechora coal basin is considered in the article. Favorable conditions and significant (about 900 billion cubic meters) methane resources predetermine the prospects of this territory for its independent production. The geological characteristics of the fields are considered and their ranking is carried out taking into account the preliminary selection of the most promising methane-coal objects. Due to the different degree of exploration of fields and the lack of (complete or partial) necessary data, some of the geological indicators served as evaluation criteria, and the preliminary assessment carried out. The prospects of four fields for the experimental work on the methane extraction opportunities are justified.

At present, the proven oil reserves from traditional Russian reservoirs are decreasing, leading to a steady fall in oil production. One of the possible ways to maintain the oil production at the present level is to produce tight oil, which is regarded as the category of oil from the Bazhenov Formation in the Kanty-Mansiysk region of Western Siberia, Domanik deposits in the Volga–Ural province, and Maikop deposits in the Fore-Caucasus.

The results from studying the rare, trace, non-ferrous, and precious metals in coals and carbonaceous rocks of Korf and Echvayam brown coal deposits (Kamchatka Krai) are given. It was established that brown coals contain economic cut-off grades of Sc, V, Cu, REEs, and platinum group metals that are typical of the known types of ores. The data on the contents of a number of metals in coals of the Korf and Echvayam deposits (Kamchatka Krai) are published for the first time.

This study presents new ICP spectroscopy data on lanthanide concentrations in early Carboniferous coal deposits in the Volga-Ural region. The results confirmed an overall LREE over HREE enrichment and emphasized the role of carbonate host strata as a major factor that is responsible for REE enrichment and geochemical anomalies. The results of this study were also used to identify the modes of REE occurrences in the organic and inorganic constituents of coal.

This study presents the results of SEM-EDX analysis of the mineral components of coals from the Kama (Volga-Ural region) and Donets basins and discusses the characteristics of the depositional environments and conditions of coalification. The results reveal differences in the mineral composition of coals from these two basins.

The data on the Re-bearing Dictyonema shale in the Baltic basin within the Leningrad Region are reported. The material and petrographic black-shale composition is studied to establish rhenium identification features, Dictyonema shale formation conditions, and the effect of volcanism on the development of rhenium mineralization. The relationship of rhenium with other metals, especially, uranium, is investigated.