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—A comprehensive study of Domanik deposits of the Timan–Pechora Basin has been carried out. The examined composition of hydrocarbon biomarkers, chemical structure of kerogen, carbon isotope composition, and rock lithology, the Rock-Eval pyrolysis data, and the contents of bitumen and Corg in the rocks give an insight into the geochemical processes in the oil window in the Domanik deposits, which took place at Tmax = 435–450 °C. The bitumen coefficient βCB is maximum in this temperature interval, reaching 30%. The obtained data on the distribution of polycyclic biomarkers in the Domanik rocks and the bitumen and Rock-Eval pyrolysis data allowed determining the boundary values of biomarker maturity coefficients in the study of the maturation of organic matter of the rocks. The carbon isotope composition of bitumen fractions in the Domanik rocks is considered, and the bimodal distribution of the δ13C values of the bitumen is shown.

Oils in Tatarstan were determined to have been generated in at least two source rock formations, whose organic matter (OM) differed in genesis, redox conditions of sedimentation, and maturity. The oils of type 1 are hosted in Devonian terrigenous reservoir rocks, whereas the oils of type 2 occur in overlying reservoirs. Differences between the oils are reliably identified in most compositional parameters of saturated biomarkers, with the values of the two oil groups not overlapping for two parameters: Ts/Tm and t22/t21. The maturity of the group-1 oils is statistically significantly higher than that of the group-2 ones. The source rocks are identical at the macrolevel: the original organic matter was deposited in marine sedimentation environments under reducing conditions, which is consistent with literature data. Comparison of the compositions of the oils and OM of the Domanik Formation indicates that rocks of the Mukhanovo–Erokhov trough were not involved in producing oil accumulations in Tatarstan. Differences were also detected between genetic characteristics of oils from the terrigenous Devonian rocks and Domanik Formation in the arch part of the area. Organic matter in the arch part of the territory could be significantly involved in the generation of oil accumulations hosted in reservoirs in the Semiluk and higher horizons. It is demonstrated that earlier conclusions that the source rocks of certain oil groups differed in lithology are groundless. To estimate the confidence interval for the median values, a criterion of signs was proposed, which has never before been employed in organic geochemistry.

—The composition of compounds employed as markers for anoxia in the photic layer of the sedimentation basin is studied in samples from Upper Devonian domanik-type sediments (Sargaevian, Semilukian, and Mendymian horizons, Famennian stage), which are widespread over the Volga–Urals basin. The studies were carried out along the north-south section spanning the northern and central parts of the Volga–Urals areas. The H2S contamination of photic layer was determined over the most part of the studied territory. During the Semilukian time, the boundary of H2S contamination passed through the middle part of the near-slope zone of the Mukhanovo–Erokhov Trough; the contamination reached the highest thickness in the northern part of the region. The intense H2S contamination also occurred in this part in the Pashiiskian and Sargaevian time. The Mukhanovo–Erokhov Trough during Mendymian and Famennian was characterized by a strong change of setting: from a steady strong contamination to its complete absence. It is shown that changes in the content of anoxia markers in samples from the the Kama–Belsk Basin and South Tatar Arch were caused by variations of thickness of the contaminated layer. It is revealed that the processes of complete hydrogenation of initial polyenes prevail over cyclization for the domanik-type sediments over the entire region. It was found that the ratio of the total content of alkyl benzenes in the fraction of aromatic compounds to the total content of products of complete hydrogenation of initial polyenes in OM from the domanik-type sediments of the studied areas does not depend on the OM maturity. Explanation of this fact is proposed.

It is established that the source rocks for the oils of Tatarstan was formed under similar conditions in the presence of anoxia in the photic layer of the sedimentation basin that existed during the whole time of accumulation of the initial organic matter at a considerable thickness of the layer infected with hydrogen sulphide. It is not excluded that disturbances in the existence of anoxia existed or thickness of the infected layer was reduced that resulted in decreasing of anoxia markers content for some oils. Biocenoses of microflora in the sedimentation layer contaminated by hydrogen sulfide demonstrate high stability. Transformation conditions of the buried organic matter in diagenesis and catagenesis were uniform, which manifests itself in approximately the same ratio between the depth of the complete hydrogenation and cyclization of the initial polyene aromatic carotenoids, the closeness of the molecular mass distributions of the C-C bond destruction products of components C40 and relatively small differences in the total concentration of monoaromatic compounds and the sum of hydrogenated analogs of the initial aromatic carotenoids. Analysis of content of the components – anoxia markers throughout the whole Devonian section is needed to establish the complexes that generated oils of Tatarstan.

The source rocks of the oils in Tatarstan were determined to be formed under similar conditions, at anoxia in the photic layer of the sedimentation basin, with anoxia continuing throughout the whole time when the initial organic matter was accumulated, at a significant thickness of the H2S-infected layer. For some of the oils, disturbances in the anoxia may have occurred, or the thickness of the H2S-infected layer may have been reduced, and this resulted in a decrease in the content of anoxia markers in these oils. Biocenoses of microflora in the sedimentation layer contaminated with H2S show evidence of high stability. Transformation conditions of the buried organic matter in the course of diagenesis and catagenesis were uniform, as follows from the merely insignificantly varying relations between the depth of the complete hydrogenation and cyclization of the initial polyene aromatic carotenoids, the similarity in the molecular mass distributions of the destruction products of the C–C bond in C40 components, and the relatively small differences in ratios of the total concentration of monoaromatic compounds to the totals of hydrogenated analogues of the initial aromatic carotenoids. The source rocks of oils in Tatarstan can be identified based on analysis for concentrations of components that are anoxia markers in all of the Devonian rocks.

The Bazhenov formation is one of the most famous and promising shale formations in Russia. The ambiguity of the ideas about its geological features, which is caused by the complex and heterogeneous structure of the stratum, has been noted many researchers. In this work, the Bazhenov Formation is united with its stratigraphic analogues as the Bazhenov high-carbon formation (BHCF). The main characteristics of its integration and distribution over the area, as well as the geological structure are considered. As an unconventional hydrocarbon reservoir, the BHCF has properties of an oil-source rock, one of the main characteristics of which is organic matter, that is, its type and maturity. The results of studying the organic matter by different methods at the microlevel, as well as their integration with larger-scale studies, are presented. The need for detailed consideration of organic matter in the BHCF is justified by the fact that it has a mixed composition and, as a consequence, a different maturity and spatial distribution in a rock.

Rocks enriched with organic matter (OM) are considered: Baltic combustible shale-kukersites and domanic deposits of the Volga-Ural basin, in which organic matter is one of the rock-forming components. The discrepancy between the volume and weight ratios of organic and mineral matter of rocks is noted. The volume significance of the OM of these rocks in the thickness of shale formations and domanic sediments is shown. The high content of OM determines the reduced strength of such rocks. The variability of OM concentrations and other irregularities of shale formations and Domanic rocks (texture, nodule bodies, etc.) are factors of mosaic distribution of areas with different density-strength properties and, as a result, non-uniform reduction of layers and their deformation in case of loss (full or partial) of organic matter.

Oil-geological work in the Pripyat oil and gas basin has been going on for over 70 years; to date, more then 80 oil and gas fields have been discovered there, but due to the ever-growing need for energy consumption, work on the identification of new resources is constantly continuing. Geochemical studies of oil deposits, as well as 3D modeling of the processes of generation, emigration and accumulation of hydrocarbons, taking into account all risk factors, made it possible to identify promising objects for oil and gas exploration in the subsalt and intersalt carbonate complexes. The calculated scales of generation, emigration and accumulation of hydrocarbons, carried out as a result of geochemical and basin modeling, turned out to be comparable and showed that the oil and gas source potential of the Devonian sediments of the Pripyat trough was realized by no more than one third.

Use of infrared spectrometry method for examination of bituminous components of dispersed organic matter in Mesozoic and Cenozoic deposits of the Azov-Kuban petroleum basin gave very important information about conditions of formation of source rocks containing organic matter and the degree of its diagenetic or catagenetic transformation level. Character of infrared spectrums represented by 15 genetic types of chloroform bitumen allows to subdivide the zones with the source beds absence, zones of oil generation and zones where this processes have come to the end.

This study presents data on concentrations of n-alkylbenzenes, n-alkylnaphthalenes, phytanylnaphthalene, and methylphytanylnaphthalene in representative crude oils of Tatarstan. The results of the study reveal the elevated concentrations of C19, C21, and C23 homologues of n-alkylbenzenes and n-alkylnaphthalenes, which can be considered as biomarkers. The proposed procedure for comprehensive quantification of this group of biomarkers can be used as an efficient tool to study oils from the major petroleum basins of Russia. Based on the results of the study, four genetic groups of oils in Tatarstan have been distinguished: (1) oils from the north and northwest (Bir saddle, Lower Kama system of linear faults, and Saraily saddle), (2) oils from Devonian terrigenous reservoirs within the South Tatar arch and Melekes depression, (3) oils from Carboniferous reservoirs, and (4) oils from Devonian carbonate reservoirs. All these oils belong to the same genetic macrotype. Based on the results of this study, the sedimentary sections of the Melekes depression cannot be regarded as potential source rocks. It is assumed that oil has migrated to the northern part of the region from the north or east. Some of the possible migration routes for oils from the remaining part of Tatarstan are from the southeast and/or south.

The composition of saturated biomarkers (alkanes, steranes, and triterpanes) in the Upper Devonian sediments (the Sargaev, Semiluk, and Mendym horizons, the Famennian stage) that belong to the Domanik formation, which is widespread on the territory of the Volga-Ural basin, was studied. The section elongated from N to S that covers the northern and central regions of the Volga-Ural basin was observed. A set of 21 parameters was used to characterize saturated hydrocarbons, including those rarely used in geochemical studies. For each parameter a set of mean values for the considered region as a whole and its individual parts was calculated and distribution-density plots were built. It was established that the most representative parameter for characterizing the Domanik-type deposits as a whole is a highly specific parameter, that is, the ratio of 29,30-bisnorhopane C28 to hopane C29. Most of the characteristics of the genetic composition demonstrate the difference between the organic matter (OM) of the vault part of the region and the Mukhanov- Erokhovsky trough. There are large differences in the parameters that characterize the maturity of OM. The characteristic values of the parameters for both the vault and the depression zone are given; two to three genetic groups of OM were determined for the majority of the parameters in both regions. A method for constructing the distribution-density graphs of the parameters is proposed that makes it possible to take their features fully into account.

In response to the wide variety of external and internal signals, mammalian cells undergo apoptosis, programmed cell death. Dysregulation of apoptosis is involved in multiple human diseases, including cancer, autoimmunity, and ischemic injuries. Two types of apoptosis have been described: the caspase-dependent one, leading to digestion of cellular proteins, and caspase-independent apoptosis, resulting in DNA fragmentation. The latter type of apoptosis is executed by AIF protein and is believed to have appeared first during evolution. The key step in the caspase-independent apoptosis program is the dissociation of AIF from the outer mitochondrial membrane (OMM). However, the molecular mechanism of interaction between AIF and OMM remains poorly understood. In this study, we demonstrated that AIF can bind to OMM via mortalin protein. We confirmed interaction between AIF and mortalin both in vitro and in vivo and mapped the amino acid sequences that are important for the binding of these proteins. Next, we showed that apoptosis induction by chemotherapy leads to downregulation of AIF-mortalin interaction and dissociation of AIF from the OMM. Finally, a bioinformatic analysis demonstrated that a high level of mortalin expression correlates with a worse survival prognosis for glioma patients. Altogether, our data revealed that mortalin plays an important role in the regulation of the caspase-independent apoptotic pathway and allowed us to speculate that inhibition of AIF-mortalin interaction may induce a dissociation of AIF from the OMM and subsequent apoptosis of cancer cells.

Samples of carbonate and siliceous-carbonate deposits of Semiluk—Sargaev horizons of the N‒NE slope of the South Tatar uplift, Volga-Ural petroliferous basin, have been studied. Specific feature of the source rocks—high concentration of compounds—anoxia testifiers in the photic layer has been identified. That is, organic matter has been deposited under the conditions of the constant presence of anoxia in the photic layer of the sedimentation basin at sufficiently high thickness of the water column contaminated with hydrogen sulfide. Since by the composition of saturated hydrocarbons the studied samples are typical for deposits of the Semiluk horizon of the central part of the Volga-Ural basin, we can assume a fairly wide prevalence of such conditions within the South-Tatar arch. Changes in the concentrations of the components—anoxia markers—show cyclical changes in output layer contaminated with hydrogen sulfide or its bioproduction within the studied time.

Petrophysical, geochemical and lithological features of the Domanik formation rock structure are considered. Particular attention is paid to the formation of the pore space in the pelitic carbon-enriched deposits within the depressions. The latter are characterized by low reservoir properties, heightened content of organic matter and siliceous-carbonate composition. Sedimentation and post-sedimentation factors affecting formation of pores filled with micro-oil are identified. High generation potential of rocks capable of generating and giving off liquid hydrocarbons at early stages of catagenesis is singled out. The pore space in carbonate complexes of shallow-marine origin overlapping carbon-enriched deposits is described. In spite of oil and bitumen saturation of these rocks, the predominant migratory character of hydrocarbons was noted.

The international interest in shale oil has recently provoked special attention to the Russian unconventional oil-source formations, including the Bazhenov Formation of West Siberia, domanik deposits in the Volga–Ural region, and the lower Maikop Group of the Cis-Caucasus. High contents of para-autochthonous soluble organic matter (bitumen) in clayey–carbonate, clayey–siliceous, carbonate–clayey–siliceous rocks with low filtration–capacity properties results in significant uncertainties in the identification of the generation potential of organic matter (OM). Examination of a large database on the OM of the Bazhenov Formation allowed us to propose an optimum complex technique for study of the source rock potential and assessment of the amount of produced hydrocarbons in the kerogen-rich sediments. The investigations include a combination of Rock Eval pyrolysis prior to and after extraction with different solvents, the comparison of bituminological and pyrolytic characteristics, and the determination of the group composition of soluble organic matter, as well as chromatography and chromato-mass spectrometry.

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.

Synthesis, analysis, and interpretation of the data on the distribution of organic material in the Cenozoic sediments of the Azov-Kuban Petroleum Basin have shown that this distribution is caused by transgressive-regressive sedimentation cycles. Within the Cenozoic sedimentation megacycle, several transgressive-regressive sedimentation cycles and subcycles can be distinguished. Transgressive subcycles are associated with the expansion and deepening of the basin. Based on the geochemical data, the beginning of a new transgressive-regressive subcycle is associated with an increase in the organic matter content of the rocks, suggesting the good petroleum potential of the region.

Bathylaimus anatolii sp. n. is described and illustrated. The new species resembles B. capacosus Hopper, 1962 but differs from the latter by shorter setae, body and by the c-index and has three onchs in the buccal cavity. The seasonal dynamics of abundance, proportion of adults and larvae, as well as the gravid and nongravid females and males were studied. An elongated breeding season from April to November and a long spring-summer peak of population density with a winter minimum at low temperatures for B. anatolii are characteristic in Peter the Great Bay.

The composition and structure of principal key-sections for the Tira (Late Vendian) and Danilovo (Late Vendian-Early Cambrian) Horizons were characterized on the basis of deep-drilling data and studies of natural outcrops along the peripheries of the Kureika syneclise. The typical sedimentary formations/associations were recognized, their vertical and lateral successions were distinguished, and their deposition environments were interpreted. A distribution pattern scheme of thicknesses and depositional environments of Upper Vendian-Lower Cambrian deposits was compiled at the 1: 1000000 scale. The reservoir characteristics of the formations are discussed and forecasted for poorly studied areas of the northwestern Siberian platform.

Source rocks are present in all the stratigraphic units of the Mesozoic-Cenozoic deposits of the Turkmen shelf in the Caspian Sea. The highest source rock potential is characteristic of I terrigenous and carbonate-terrigenous rocks of Middle Jurassic age, and the Aptian, Paleogene, Neogene and Apsheron stages of the Quaternary system. To reveal the formation conditions of hydrocarbon deposits within Southwestern Turkmenistan, the principle of chemical thermodynamics is primarily used via the calculation of the free energy of gaseous hydrocarbons. This showed that hydrocarbon deposits within the topmost depositional complex (the red-colored strata of the Middle Miocene at the Akchagyl and Apsheron stages) are syngenetic; their formation was due to lateral migration from even-aged deposits from depression zones neighboring the uplifts.

The paper summarizes data on the geology, lithology, and geochemistry of petroliferous Riphean, Vendian, and Lower Cambrian rocks in the central parts of the Siberian Craton. The petrological-geological properties of these sediments have been assessed based on results of paleogeographic analysis of these rocks, discrimination of oil reservoirs and oil-source successions, determination of secondary alterations of the rocks, and sources of oil generation and regional migration of hydrocarbons into various traps in zones of possible oiland-gas accumulation.

Data on heavy metal contents in polychaetes and free-living nematodes inhabiting the bottom sed- iments of Zolotoi Rog Bay near the port of Vladivostok are reported. Chronically high contents of heavy metals (Fe, Cu, Zn, and Cd) were found in the bottom sediments and in the infauna. The levels of some toxic elements in tissues of the polychaete Dorvillea (Schistomeringos) japonica inhabiting polluted sediments of Zolotoi Rog Bay were higher than in worms of this species from relatively clean areas of the Sea of Japan. Similar high con- centrations of Fe were found in the polychaete Capitella capitata and the nematode Oncholaimium ramosum. The highest concentrations of Fe, Zn, Cu, and Cd were found in tissues of the free-living nematode O. ramosum. Chronic heavy pollution of the bottom sediments leads to a decrease in the biodiversity of the infauna and to specific metal-tolerant communities.

The result of general geochemical investigations and biomarker analyses are present in this paper. Bazhenov Formation is organic matter – enriched formation of Late Jurassic- Early Cretaceous age. It is located within the West Siberian petroliferous basin. The most of authors recognize that the Bazhenov formation is the main source rock of West Siberian basin. Moreover, since the 70s of the last century own oil and gas potential of the Bazhenov formation is known. The detailed biomaker investigations of organic matter of Bazhenov formation allow to suggest pattern of distribution of hydrocarbon accumulations; to ascertain paleofacies depositional environment of Bazhenov formation and characteristics of bioproduce; to clarify the variability of microfacies. The last one allows to predict own oil and gas potential of the Bazhenov formation.

The Maikop Series widely distributed in the Caucasus-Skythian region consists of clayey rocks with abundant organic matter (OM). Sequences of similar geological age accumulated in marginal basins are characterized by high petroleum potential and in certain cases contain petroleum accumulations. Marine sedimentation environments, clayey composition, sapropelic OM type and presence of petroleum accumulations make MS a classical example of an oil-producing sequence. It is the main oil source present in Cenozoic and, most probably, Upper Cretaceous strata in the Caucasus-Skythian region. However, oil reserves pooled in the Cenozoic reservoirs of the region are incomparably lower than that which could be expected in view of the above conditions.

Authors have identified a complex Paleozoic petroleum system represented by 5 major source rocks with good up to excellent characteristics from the point of petroleum potential, reservoirs of porous and fractured types, regional and local seals. Processes of generation, migration, accumulation and conservation of HCs occurred within the limits of this system. Moreover, 2 potential hydrocarbon systems were formed: Mezo-Cenozoic oil system which source rocks within the main part of the area have not entered conditions favorable for HC generation; Ordovician-Silurian petroleum system which source rocks have mostly worked out their petroleum potential and have possibly carried out significant input in petroleum potential of the area. Main source rocks reached oil window zone, and Devonian rocks partially reached gas zone. Main critical moment for Paleozoic rocks – Early Permian time at maximal rock submergence at high geothermal gradient. Subsequently Paleozoic deposits did not reach the same temperatures, i.e. secondary activation of HC generation processes did not occur.

P258 Oil-Gas-Bearing Capacity of Anadyr Basin E.N. Poludetkina* (Lomonosov Moscow State University) O.K. Bazhenova (Lomonosov Moscow State University) & N.P. Fadeeva (Lomonosov Moscow State University) SUMMARY Source rocks within Anadyr basin are present throughout the whole Paleogene-Neogene sedimentary sequence. Peculiarities of Anadyr basin as in the other Cenozoic sedimentary basins of the Far East is absence of good petroleogenetic deposits that is determined by the initial type of kerogen – influence of hymic OM is becoming apparent to a greater or lesser extent in all petroleogenetic rocks of the Anadyr basin. Considerable facial-genetic heterogeneity of OM and intensive multi-phase migration

Wide occurrence of Pre-Cambrian sedimentary formations, regional association of commercial oil-gas deposits and oil-shows let to consider Upper Proterozoic deposits of ancient platforms as promising object in respect of oil-gas content itself and as a source of oil in Paleozoic as well. Commercial oil-gas bearing established in South Oman, China and mainly Siberian Platform with main oilbering regions Nepsko-Botuobinsk and Bajkits anticlines. Small oil deposits were discovered in the East-European platform in Vendian and Riphean deposits.