In recent years, industrial accumulations of hydrocarbons in the domanicoid deposits of the Volga-Ural oil and gas basin have been identified on the territory of the Samara and Orenburg regions. This article discusses the prospects for the search for hydrocarbons in domanicoid deposits on the territory of the Republic of Bashkortostan. One of the main tasks is to determine intervals with capacitive properties and a total thickness sufficient for the forming industrial accumulations of oil and gas. To identify such intervals, the section of the domanicoid organic-rich formation was divided into rock units. Their porosity and permeability properties were studied, and the most favorable types of section for reservoir maintenance were determined by the nature of the interbedding of rock units. Three types of rock units are identified: carbonate-siliceous rocks with a high content of organic matter; frequent interbedding of carbonate-siliceous and siliceous-carbonate rocks; predominantly carbonate rocks. Each individual unit contains reservoir rocks with fractured-porous and porous-fissured void space. Members compose cyclites of different scales, correlate with each other and meet certain conditions of sedimentation. The set of units determines the type of section. Three types of sections are distinguished in domanicoid deposits, corresponding to different paleostructural zones of their accumulation: the intrashelf basin, the slope of the intrashelf basin, and the shelf of the carbonate platform. The analysis of the capacitive properties of the rocks of each unit made it possible to proceed to the prediction of the quality of the reservoir properties based on the data of geophysical well surveys. The nuclear magnetic log data formed the basis of the dependences of porosity values on the neutron log values. The results of the study showed that the second unit type, represented by the interbedding strata of siliceous-carbonate and carbonate-siliceous rocks, contain the largest number of capacious and high-capacity reservoir rocks, the distribution area of which within the domanicoid organic-rich formation is associated with the Frasnian-Famennian section of intrashelf basins. A relatively high flow rate was also recorded from the unit of the second type, which allows us to conclude that the units of this type are the most promising. On the basis of these studies, a general map of forecast zones of development of capacious and high-capacity reservoir rocks within the organic-rich domanikoid formation in the territory of the Republic of Bashkortostan was built.
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