This article presents an approach to assessing the potential of Jurassic complex deposits in a subsurface area within the Krasnoleninsky oil and gas region, taking into account the specific geological structures of this region. An analysis of regional paleogeographic environments during the time of sediment formation and local mechanisms of sedimentation is provided. By analyzing core material from adjacent territories, secondary processes controlling reservoir properties in Jurassic reservoirs were identified. The patterns and features of hydrothermal influence on primary reservoir rocks in the contact zone with the pre-Jurassic complex and in distal zones are described. The impact of these secondary changes on the pore structure and hydrocarbon potential was determined. It was found that the sediments most promising for hydrocarbon exploration predominantly have colluvial-deluvial genesis, as they accumulated directly on slopes and at their bases, forming the basal horizon. Based on this research, combined with comprehensive analysis of seismic data, geophysical surveys, well tests, and the analysis of geological history of the area, a conceptual model of the subsurface structure and prospective targets has been developed. Their key exploration criteria and methods for resource base assessment are also discussed. The results of the work were used in the geological and economic assessment when selecting a development system, calculating predicted production profiles, forming a program of geological exploration work and as a result assessing the expected value of the asset and making a decision on the acquisition of the asset.
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