Реконструирована палеогеография Западной Сибири в мелу. Приведены и детально описаны па-леогеографические карты для отдельных веков мелового периода, которые отражают основные этапы формирования Западно-Сибирского осадочного бассейна. Представленный авторами набор карт пост-роен исходя из модели лавинного бокового заполнения в волжско-барремское время относительно глу-боководного морского бассейна в регрессивный этап крупного седиментационного цикла. Реконструи-рован рельеф и распределение внешних источников сноса терригенного материала. Палеогеография, мел, клиноформы, лавинная седиментация, Западно-Сибирский осадочный бассейн. For paleogeographic reconstruction of the West Siberian basin during the Cretaceous we used a set of pa-leogeographic maps, which were compiled for the main epochs of the Cretaceous period. The paleogeographic maps presented in this study suggest progradational fi lling of the deep basin with avalanche-type sedimentation during Volgian-Barremian regression. The paleorelief and provenance of terrigenous sediments were reconstructed. Paleogeography, Cretaceous, clinoforms, avalanch-type sedimentation, West Siberian sedimentary basin ВВЕДЕНИЕ Ранее была рассмотрена палеогеография юры [Конторович и др., 2013]. Юрский комплекс отло-жений Западной Сибири уникально обогащен, особенно породы волжского века (баженовская свита) органическим веществом и являлся главным генератором нефти и газа в Западно-Сибирском бассейне. В перекрывающем его меловом осадочном комплексе сформированы основные резервуары, содержа-щие значительную часть ресурсов нефти и газа этого уникального осадочного бассейна. При формиро-вании залежей углеводородов в меловом комплексе решающую роль играли процессы вертикальной миграции. Палеогеография мелового периода предопределила распределение в разрезе мела проницае-мых комплексов и флюидоупоров и в значительной степени их качество. Настоящая работа посвящена палеогеографии мелового периода. Юрский период в истории Земли закончился крупной (глобальной) трансгрессией. К концу волж-ского века на территории Западно-Сибирского осадочного бассейна сформировался глубоководный эпиконтинентальный морской бассейн. Максимальные глубины этого моря, по разным оценкам, дости-гали от 400 до 800 м

Numerical models are developed to predict the generation, accumulation, and escape of hydrocarbons at the time of sediment accumulation (basin modeling) in the West Siberian geosyneclise during the Jurassic, Cretaceous, and Cenozoic. A theoretical framework for such computer models is presented with a special emphasis on modeling of gas generation during early catagenesis. The study provides a description of the algorithm used for interpretation of simulation results and considers the stages of formation of a shale cap rock during lithogenesis. Peak oil generation began in the Aptian and continued for about 80 Myr until Eocene–Miocene times; gas generation in the late catagenetic window took place from the Valanginian to the Maastrichtian. Numerical simulations show that the major oil-prone source rocks in the South Kara kitchen area were, in the decreasing order of potential, the Bazhenovo (Yanov Stan), Kiterbyut, and Malyshevka Formations. The Upper Jurassic regional rock unit generated over 60% of liquid hydrocarbons and heterocyclic compounds (oils). The major gas-prone source rocks in the area were, in the decreasing order of potential, the Kiterbyut, Malyshevka, Alym, and Bazhenovo (Yanov Stan) Formations. The Lower and Middle Jurassic regional rock units generated about 65% of hydrocarbon gases. Results are presented to quantify the amount of hydrocarbons dissipated due to either the absence or poor effectiveness of confining seals and to explore the role of Cenozoic tectonic processes in the formation of petroleum accumulations in the basin.

Much work at A.A. Trofimuk Institute of Petroleum Geology and Geophysics (Novosibirsk) has been done to synthesize geological and geophysical data from the Siberian Arctic and Arctic shelf. Namely, seismic-geological modeling and petroleum potential assessment have been performed for the Neoproterozoic–Phanerozoic section of the Anabar–Lena province in the northern Sakha Republic (Yakutia). The results include seismic-geological division, a set of structural maps, and structural, paleotectonic, and facies analysis. The study shows that Riphean, Vendian, Cambrian, and Permian sequences are of interest in terms of petroleum potential; oil and gas may accumulate in traps of different types.

The Borehole Vostok 3 drilled in the east of the West Siberian Plate (Tomsk Region) revealed a Vendian section in the depth range 5002–3870 m, which was subdivided into the Poiga, Kotodzha, and Raiga Formations based on geological, geophysical, and paleontological data. In the Kotodzha and Raiga Formations, typical Upper Vendian fossils of Cloudina hartmanae and Namacalathus sp. were found along with diverse Platysolenites, which are commonly considered to be of zonal significance in Lower Cambrian strata. Hence, the stratigraphic interval with abundant diverse Platysolenites has a wider stratigraphic range than it was believed earlier and seems to cover the Upper Vendian and Lower Cambrian deposits. The Borehole Vostok 3 is the first Siberian occurrence of the fossils Namacalathus, the world’s fourth occurrence of the Cloudina-Namacalathus association, and the first site where coexisting Platysolenites and typical Vendian organisms have been found. Therefore, the borehole provides one of the most informative (in paleontological context) Upper Vendian sections.

Paleogeographic reconstruction of the West Siberian basin during the Jurassic is based on a variety of criteria used to evaluate the depositional environments (paleontological, sedimentological, geochemical, etc.). Extensive geochemical data on the hydrocarbon biomarkers in bitumen from organic matter are first used to constrain the depositional setting of this large region over a span of about 45 Myr. The study provides a detailed description of paleogeographic maps compiled for the main epochs of the Jurassic period with the reconstruction of paleorelief and differentiation of potential external and internal sources of terrigenous material. The paleogeographic reconstructions of the basin are considered with implications for the formation of regional seals and reservoir units. A special emphasis is given to interpretation of organic matter type and depositional setting of the major oil and gas source rocks. The study infers a paleogeographic control on the stratigraphic and areal distribution of hydrocarbon accumulations in the basin.

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Russia experienced a severe health crisis in the 1990s, as reflected by a drop in life expectancy. It has been suggested in literature that this poor state of health is likely to endure and will significantly retard economic growth in the country. This paper uses evidence from other former Communist countries and studies of income–health relationship across economies to evaluate these claims. It concludes that the mortality increases of 1988–94 and 1999–2000 were the effects, rather than causes, of the economic recession. The state of health is unlikely to put a brake on future economic growth.

The western part of the Yenisei–Khatanga trough is one of the least explored regions, which are thought to possess an excellent hydrocarbon resource potential. This region is geographically located in the southern part of the Taimyr Peninsula, within the Krasnoyarsk Territory. Utilizing regional seismic data, structure and thickness maps for seismic sequences allowed the reconstruction of the structural framework and tectonic evolution of the region. The study reveals a number of tectonic processes in the region that took place in the Paleozoic, Mesozoic, and Cenozoic and establishes the main evolutionary stages of a series of large structures of different ranks. The study also provides some insights into the structural features and depositional environments of Paleozoic, Triassic–Jurassic, Neocomian, Aptian–Albian–Cenomanian, and Turonian–Cenozoic sedimentary sequences. Based on the relationship between tectonic activity and hydrocarbon generation, the conclusion was made about a high hydrocarbon resource potential of the Neocomian clinoform sequence in the Yenisei–Khatanga regional trough.