The Russian sector of the Caspian Sea is one of the promising regions for the search for hydrocarbon deposits. The results obtained from the processing of seismic facies, lithological, geophysical, petrophysical and other researches indicate that the main prospects are connected with the carbonate Upper Jurassic-Lower Cretaceous complex of deposits. The development predicted at the initial stage of research in this (previously considered to be Tithonian) complex of rifogenic type traps has not been confirmed. Along with this, materials are accumulating that indicate the possible presence in this region of a significant number of non-structural oil and gas traps of lithological, stratigraphic and combined types. Search and exploration of deposits of this type dictate the need for a well-developed stratification scheme. The territory of the Northern Caspian Sea is of great scientific interest from the perspective of paleogeographic events that took place at the turn of the Jurassic and Cretaceous: it is through this region that water masses and marine biota were exchanged between the Boreal and Tethyan basins. The joint analysis of stratigraphic and paleogeographic data on the Northern Caspian Sea can provide key information for the Boreal-Tethys correlation and justification of the Jurassic-Cretaceous boundary in the boreal sections. In this regard, the initial figures about the structure of the Jurassic-Cretaceous sequence of the region that were obtained by drilling are of particular interest. It is established that the carbonate complex previously attributed to the formations of the titon tier should be considered as a transitional Tithon-Berriass, and the productive I layer, represented by fractured-cavernous dolomites, should be attributed to the Berriasian. Inter-well correlation of the refined roof of Jurassic system sediments was executed using three independent methods. The one-dimensional modeling performed taking into account the VSP and drilling data, made it possible to correctly stratigraphically link the reference horizons to the borehole data and unambiguously correlate the target horizons. The seismic facies analysis showed that in the upper part of the Upper Jurassic deposits there is a zone of the release of individual phases under the roof of the Upper Jurassic deposits. The obtained geological results confirm the assumption about the possible development of stratigraphic screening traps in this region.
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