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The type of source organic matter of West Siberian oils localized at depths of 1425 to 3950 m in Cretaceous, Jurassic, and Paleozoic deposits is determined based on the composition of bio- and geomarkers. The individual and group compositions of alkylnaphthalenes of these oils are studied. The geochemical parameters of oil transformation are calculated from the composition of methyl-, dimethyl-, and trimethylnaphthalenes. Data on the individual composition of alkylnaphthalenes are processed by the method of principal components of factor analysis. The matrix is compiled of 44 oils and 22 characteristics (contents of individual alkylnaphthalenes). The molecular-mass distributions of alkylnaphthalenes in oils of different genesis served as a basis for the separation of the latter into families according to the compositional similarity of biarenes and the degree of transformation.

Experimental data on the distribution and composition of sulfur and nitrogen compounds in oils of Paleozoic and Jurassic deposits of southeastern West Siberia have been summarized. Benzo–, dibenzo–, and naphthobenzothiophene, quinolines and benzoquinolines, thiopheno– and benzothiophenoquinolines, and benzo– and dibenzoquinolines are shown to be the main heteroorganic compounds in all the oils. It has been established that the distribution of these compounds depends on the formation conditions of natural hydrocarbon systems and on the degree of their catagenesis.

The distribution of biomarkers in bitumens of source rocks of different ages in the southern Siberian Platform is studied to elucidate the correlation between oils and their sources. It is shown that the bitumens of Riphean, Vendian, and Lower-Middle Cambrian source rocks are different in some parameters reflecting the type of primary biogenic material, first of all, in the distribution of n-alkanes and acyclic isoprenoids and in the portions of steranes and triterpanes in polycyclic naphthenes. The revealed difference in the composition and distribution of biomarkers in bitumens of source rocks of different ages can be used to identify the sources of hydrocarbons in dissolved pools.

Electromagnetic soundings with controlled and natural sources (TEM and MT, respectively) integrated with IP and geochemical surveys have been tested for petroleum exploration in West Siberia. The TEM method, with loop sizes smaller than the depth to the target, provide high resolution, sufficient penetration depth, and data locality. The MT method sounds deeper earth and can place constraints on the Paleozoic basement structure and its electrical properties. The petroleum implications of IP and geochemical data are associated with secondary alteration (mineralization) of rocks over oil traps.

Coupled geomechanic and fluid flow analysis is applied to develop theoretical and experimental background for geosteering and well logging to diagnose a state of near-wellbore formation and oil reservoir. The suggested methods of processing EM induction (VIKIZ) and Russian laterolog (RLL) resistivity responses account for effects of stress-dependent fluid flow changes. The geomechanic and fluid-flow effects on resistivity well logs are investigated for the case of asymmetric invasion and related irreversible deformation. Ways of taking into account stress-dependent effects on resistivity logs are developed on the basis of 3D modeling of geomechanic and electromagnetic fields.

We analyze the results of measurements of the thermal conductivity, porosity, and permeability of Mesozoic sedimentary rocks from wells drilled in the northeast of the West Siberian Plate and in the Cis-Yenisei basin. The thermal conductivity was measured by “Thermal-conductivity comparator”, and the porosity and permeability were determined using standard techniques. A total of 135 samples of dry rocks were studied for thermal conductivity (λ_d). Ninety-two of them were then saturated with water, and their thermal conductivity was measured again. The average thermal conductivity of dry and water-saturated (λ_w) sedimentary rocks is 1.8–2.0 W/(m·K) and 2.4–2.8 W/(m·K), respectively. Porosity factor (Kpor) was measured for 95 samples, and permeability (K_perm), for 44 samples. Comparison of the results of measurements revealed stable linear correlations between the thermal conductivity of dry samples and λ_w, Kpor, and K_perm. The established dependences are proposed for the express evaluation of the thermal (λ_w from λ_d and Kpor values) and structural (Kpor and K_perm from λ_d values) properties of sedimentary rocks, though the revealed correlations need further refinement.

Algorithms and software have been designed for petrophysical 2D forward simulation and inversion of induction logs from oil wells drilled in shaly sandstone using conductivity models for different clay types. As comparative analysis of relative amplitudes and phases of tool responses has demonstrated, it is possible to estimate reliably and accurately fluid saturation and porosity from induction logs. The applied 2D numerical inversion of both theoretical and well logs yielded quantitative estimates of petrophysical parameters of reservoirs, with clay volume fraction assumed according to the chosen conductivity model. Correction for the presence of clay improves inversion quality if clay content as well as type are taken into account.

Acid catalytic condensation of 1,3-butadiene with para -quinones and the oxidation of resulting adducts can be performed in one technological stage in the presence of the aqueous solutions of Мо–V–P heteropolyacids (HPA) of general composition H_aP_zMo_yV_xO_b. These solutions possess bifunctional catalytic properties being strong Brønsted acids and rather strong reversibly acting oxidizers at the same time. The condensation of 1,4-naphthoquinone with 1,3-butadiene in HPA solutions leads to obtaining 9,10-anthraquinone (AQ) in mixture with tetrahydroanthraquinone (THA) and dihydroanthraquinone (DHA). In the course of a single-stage process without organic solvents, the HPA solution is reduced and poorly soluble mixture of THA, DHA and AQ (up to 50 %) precipitates almost quantitatively from the solution. The yield and purity of AQ can be improved substantially due to the use of organic solvents miscible with water (for example, acetone, 1,4-dioxane), as well as high-vanadium HPA of the composition H₁₅P₄Mo₁₈V₇O₈₉ and H₁₇P₃Mo₁₆V₁₀O₈₉. Optimization of the process allowed us to obtain the product containing not less than 90 % AQ. Results achieved in the work open outlooks for the development of low-waste process for the production of AQ from 1,3-butadiene and 1,4-naphthoquinone.

Atmospheric aerosols inherent in two areas of the Far East cities such as the Vladivostok and Ussuriysk were studied. Three of the 21 pairs of the samples of fresh snow and dry air suspensions taken in different parts of these cities exhibited the presence of iron, chromium, lead and zinc nano- and microparticles. Therewith, the nanoparticles were registered for the samples taken near the electroplating production enterprises, whereas the microparticles were observed near the roads with an intense traffic.

Studies were performed concerning the process of obtaining noble metals (gold, silver, platinum, palladium) and tellurium, involving the following process stages: dissolving the gold and silver alloy in nitric acid solutions in the presence of ammonium nitrate under the gas phase pressure; purifying the leaching solutions via sorption (from platinum and palladium) and via hydrolytic precipitation (from copper and tellurium); electrochemical extraction of silver-containing solutions to produce cathode silver; conditioning and refining the gold sludge; an electrochemical extraction of eluates containing platinum group metals; obtaining tellurium concentrate. The number and type of linearly independent reactions have been found out for the dissolution of the parent alloy, key components for the stoichiometric description of chemical reactions in the system have been identified. A mathematical evaluation of quantitative changes in the complicated heterogeneous system with polyvalent nitrogen is presented.