A comprehensive approach to developing carbonate reservoir in the fields of the Orenburg region

The oil-and-gas fields of the Volga-Ural basin have been developed for many decades. Nevertheless, the region still contains significant hydrocarbon reserves in carbonate formations. However, the low permeability and thin oil-bearing intervals prevent their cost-effective development. This article presents a comprehensive approach for designing development systems for such reserves, using the Orenburg oil and gas condensate field as an example. Conventional development planning method designed for terrigenous reservoir is often ineffective for complex reservoir, necessitating a revision of the method. This work focuses on identifying reservoir types by using all available data, including core, seismic, well logging, and well testing data, along with modern seismic processing techniques. By gaining a deeper understanding of the reservoir types and their spatial distribution, the author can select the most effective development strategies, including well design and stimulation methods, at the early stages of field development. The proposed comprehensive approach improves the economic performance of developing hard-to-recover reserves by up to 20% through increased production rates during the early stages of field development.

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