Domanic deposits as an integral part of the reservoir of the Astrakhan carbonate massif

Abstract

The object of the study of this article is the high-carbon domanic deposits of the Astrakhan carbonate massif (Caspian oil and gas province), which are assigned the role of a zonal tire isolating the reservoir of the Lower Devonian-Fransk complex. The authors study the properties of these rocks that affect the insulating ability of the deposits under consideration: multilayer structure, the effect of complex stratification, the appearance of epigenetic clay material. The results of the analysis indicate that uneven concentrations of organic matter in the domanic tire predetermine the mosaic in the manifestation of the strength properties of these rocks. The peculiarity of the domanic strata is emphasized – its enrichment with solid organic matter, which is one of the rock-forming components. The opinion on the important oil and gas-mother functions of domanic deposits is supported. The ideas of the geological role of domanic rocks as (1) the oil and gas mother strata, (2) a reservoir for autochthonous hydrocarbons, (3) a regional tire for underlying sediments are expanding, which emphasizes the importance of the formation of hydrocarbon accumulations within the considered strata by the in situ mechanism. Suggestions are made on the directions of further research detailing the possibilities of domanic deposits in oil and gas formation and oil and gas accumulation. Keywords: domanic rocks; tire; reservoir; organic matter; hydrocarbons; Caspian oil and gas basin.