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More than 1500 measurements of vitrinite reflectance ( R 0Vt), along with mathematical modeling and computing, have been used to map the uppermost Middle Jurassic sediments of the West Siberian basin according to thermal maturity (catagenesis). The thermal maturity varies within the grades PC3 to AC2. Sediments are the least mature along the margins of the basin, and the maturity grade increases progressively toward its central and northern parts (grades MC21-MC2). It reaches a maximum in the north (AC2), where the sediments which subsided to large depths became exposed to high temperatures and pressures. The maturity zones of Jurassic sediments in the West Siberian basin form a typical pattern of regional catagenesis.

The structure of the junction between the Turukhan zone of deformation and the Kureika Basin was studied using regional reflection profiling data acquired along the Lower Tunguska River, with reference to well logs and land-based geological surveys. The western flank of the line comprises four large blocks separated by faults, which produce different patterns in seismic sections. The eastern part of the line covers the margin of the Kureika Basin filled with plane-bedded sediments and its border with the Turukhan Uplift and the Turukhan tectonic zone with thrust sheets.

We analyze geologic and geophysical factors enhancing the prerequisites for the high petroleum potential of East Siberia that were formulated by A.A. Trofimuk in 1960. The main updates concern the northern Siberian Platform, where it is indeed possible to significantly increase its petroleum potential and to refine the localization of large and giant, mostly oil accumulations.

We present results of lithological and geochemical studies of Paleozoic deposits stripped by drilling within the Ledyanskaya area in the north of the Tunguska syneclise. The studied section has a terrigenous sulfate-carbonate composition and is complicated by trap intrusions. We have established that the Ordovician-Devonian sedimentation proceeded within an epicontinental basin, with its depth varying from supralittoral to lower sublittoral zones. In the Carboniferous and Permian, coastal-continental sedimentation was predominant; in the Late Permian it was accompanied by volcanic activity. Analysis of the poroperm properties of rocks has distinguished three potential oil reservoirs: Silurian reef carbonate deposits and Ordovician and Carboniferous sand horizons. The Lower Silurian argillaceous-carbonate rocks and Devonian carbonate-sulfate-clay members, halite beds, dolerite bodies, and tuffaceous rocks are probably confining beds of these reservoirs. Geochemical study of organic matter has shown several possible sources of hydrocarbons: Upper Proterozoic deposits, Lower and Middle Cambrian Kuonamka complex, Middle Devonian Yukta Formation, and Upper Paleozoic coal-bearing deposits.

The Yurubchen-Kuyumba petroleum production center is being formed in the central part of Krasnoyarsk Territory, in the middle reaches of the Podkamennaya Tunguska River. It comprises the Kamo arch, the most elevated area of the Baikit anteclise, and its slopes. The main hydrocarbon (HC) resources (app. 820 mln tons) occur in the unique Riphean petroleum fields (Yurubchen and Kuyumba) of the Yurubchen-Tokhomo petroleum accumulation zone (YuT PAZ). The first commercial gas inflow was obtained from the Kuyumbinskaya-1 well in 1973, and that of oil, from the Kuyumbinskaya-2 and 9 wells in 1976. The Yurubchen-Tokhomo petropeum accumulation zone was originally established in 1986 under the ‘Complex Plan for Optimization of Regional, Prospecting, and Exploration Works in the Yurubchen-Tokhomo Petroleum Accumulation Zone’. Nowadays the main resources and reserves of oil, gas, and condensate are located in two petroliferous complexes, Riphean (main) and Vendian (supplementary). The extension, structure, and petroleum potential of the reservoirs of these complexes are discussed in the paper. To facilitate continuation of the prospecting and exploration works of the new oil fields and reservoirs, it is proposed to include the adjacent territories of the YuT PAZ (Omoro PAZ, Vaivida and Taimba petroleum prospects, Turama and Mutorai underexplored prospects) into the Yurubchen-Kuyumba petroleum production center. We propose support of stable annual oil production in the Yurubchen-Kuyumba petroleum production center as the main purpose of the petroleum exploration works.

Riphean and Vendian terrigenous complexes are not affected by trap injections within the South-Tunguska petroliferous region and thus can be considered a priority for further prospecting for hydrocarbon accumulations. Although these strata are not exposed with wells and are not characterized by core samples, their wide distribution is proved by seismic data. The obtained data and previous paleogeographic reconstructions show similar depositional environments of terrigenous sediments for the South-Tunguska and Baikit petroliferous regions. These facts substantiate criteria for the prediction of sand reservoirs within the study area. Taking into account the complex geologic structure of the South-Tunguska petroliferous region, ambiguity of seismic-data interpretation, and problems of deep-drilling technology, we provide recommendations for the geological exploration.

Large gas reserves have been discovered in the Vendian terrigenous rock complex of the Angara-Lena step in the southern Siberian Platform. In recent years, regional and areal exploration has yielded substantial data on the structure of gas-promising sedimentary strata and their reservoir properties. The author has analyzed the main structural features of Vendian gas-producing deposits and has made deterministic and probabilistic evaluation of initial hydrocarbon resources with regard to the discovered-field reserves.

Organic matter (OM) and rocks of the upper member of the Mesoproterozoic Malgin Formation in the southeastern Siberian Platform have been studied by modern research methods. Analysis has revealed homologous series of alkanes, tricyclanes, and hopanes in the bitumens. Leiosphaeridia crassa, L. Minutissima, cf. Leiosphaeridia tenuissima, cf. Glomovertella, and Oscillatoriopsis sp. have been identified among the rare microfossils preserved in mudstones. Geochemical, lithological, and paleontological studies have shown that bacterial microcommunities and, to a lesser extent, eukaryotic microorganisms were the main source of OM. Based on results of sedimentological analysis and study of biomarkers, the depositional environment has been reconstructed. A model for the accumulation of black shales and carbonate rocks of the Malgin Formation is considered. The hypothesis that the highly carbonaceous rocks formed in uncompensated depressions of shallow epicontinental marine suboxidation environments is substantiated. The petroleum potential and degree of OM catagenesis of the Malgin Formation rocks are evaluated. Pyrolysis, bitumen analysis, and hydrocarbon composition study have revealed autochthonous and parautochthonous bitumens in the oil shales, mudstones, and carbonate rocks. The obtained data show that the Malgin Formation rocks might have participated in petroleum generation in the Uchur-Maya region.

The Vendian-Riphean section of the Ust’-Maiskaya-366 parametric well was studied. The well is the first deep well drilled in the central part of the Aldan-Maya depression, in the southeast of the Siberian Platform. New probable oil source rocks within the Upper and Middle Riphean deposits have been identified based on core analysis supported by geological-survey data. We make a geochemical description of organic matter from these deposits and report the composition of abundant migrated bitumens discovered in the Ust’-Maiskaya-366 well section. The petroleum content in the Aldan-Maya depression has been predicted with regard to the new geological and geochemical data.

A computer simulation of complexes of (6,6) open carbon nanotubes (CNTs) with neutral molecules, zwitterions and glycine, alanine, and phenylalanine amino acid anions is performed. In starting structures amino acids are arranged in three types: on the external side face, the open end, and inside CNT. The structure is optimized within the density functional theory with regard to the GD3 dispersion correction with and without taking into account solvation effects. It is found that the greatest CNT-amino acid interaction occurs in the neutral aqueous medium at dissociative chemisorption of the zwitterion (adsorption energy 80-90 kcal/mol) and in the basic medium at anion chemisorption (energy ~48-50 kcal/mol) on the open CNT end.