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 study presents a seismic and geological characterization of the Meso-Cenozoic sedimentary cover of the Nadym–Pur interfluve area and discusses the morphology of the Jurassic and Aptian–Albian–Cenomanian sedimentary complexes, formation history of structures, and geologic processes responsible for the formation of Cenomanian gas accumulations.

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.

The study presents a description of a new type of Cambrian section penetrated in Vostok 4 well in the southeastern part of the West Siberian geosyneclise (Krasnoyarsk Territory). The drilled succession is well characterized by the fossil evidence and can be considered a key section for the east of the WSG. The section comprises all three divisions of the Cambrian and is subdivided into the Oksym, Tyya, Averin, Kolchum, and Evenki Formations, based on the composite log data for an interval of 2262–5105 m. The Oksym Formation (the age equivalent of the Usol’e Formation) and Kolchum Formation are first identified and described in this study. The section is mostly carbonate, argillaceous–carbonate, sulfate–carbonate, and terrigenous sediments deposited in a back-reef setting of the Yenisei salt-bearing basin.

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