Geological heterogeneity makes it difficult to assess the reservoir and predict the nature of saturation of the carbonate stratum of the Kashiro-Podolsk deposits, widespread in the Volga-Ural oil and gas province. An integrated approach to assessing heterogeneity and typification of rocks will increase the success of geological and technological measures when involving them in development.
The field in question is the largest in the Republic of Bashkortostan in terms of geological reserves. It is at a late stage of development with high water cut along the main terrigenous layers. Kashirskian-Podolskian deposits are stratigraphically related to the Moscow stage of medium carbon, the total thickness is 100-190m. Previously, before the development of the main reserves, it was an overlying transit object and was drilled by directional wells with a small inclination of the wellbore. Effective thicknesses did not exceed ten meters. Oil launch rates were limited to 5 tons/day. There was a significant water cut in the first months of well development.
Numerous estimates of the reservoir potential of Kashir-Podolsk deposits have revealed a complex structure associated with lithological and structural heterogeneity of rocks.
The purpose of this work is to analyze new field data, the results of core and well logging to clarify the types, quality and characteristics of reservoirs.
Special core studies, lithological and petroelastic modeling were carried out to solve the tasks.
The main results of the study are: typification of the section by type and quality of the reservoir; the conclusion about the confinement of reservoir to pore and cavern-pore dolomite; understanding the influence of microporous rock on filtration processes.
References
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