No.1(45),2026 PP.55-75

Neftyanaya provintsiya No. 1(45), 2026

An Integrated Approach for Dual-Medium Characterization at Carbonate Field Appraisal Stage

A.V. Gavrilov, S.E. Togaev, A.G. Klevitskiy
DOI: https://doi.org/10.25689/NP.2026.1.55-75

Abstract

This paper describes an integrated approach to determining flow and storage properties of naturally fractured reservoirs, applied during the appraisal stage of a gas field in the Surkhandarya region of the Republic of Uzbekistan. Particular attention is given to estimating fracture compressibility, which at the appraisal stage represents one of the most uncertain dual-medium parameters and significantly influences production forecasts, especially for fields with abnormally high initial reservoir pressure. The proposed method is based on integrating the following stages: (1) conducting specialized field studies, including a suite of well logging methods characterizing natural fracture properties, and a special well testing technique – interwell pulse testing; (2) constructing a discrete fracture network model (DFN) and a dual-medium simulation model using the dual-porosity (DP) approach; (3) history matching the hydrodynamic model to pulse test results with quantitative determination of dual-medium parameters: permeability, porosity, and compressibility of both fractures and matrix. The proposed approach enables reduction of uncertainty ranges for properties of fractured reservoirs prior to pilot production, thereby improving the reliability of development forecasts at early stages of field development.

Key words:

naturally fractured reservoir, fracture void compressibility, interference testing, dual porosity, Surkhandarya oil and gas region

References

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Authors

A.V. Gavrilov, Deputy General Director for Geophysics, Geology and Reservoir Engineering, Surhan Gas Chemical Operating Company» LLC
47 Bunyodkor Ave., Tashkent, 100161, Uzbekistan
E-mail: aleksey.gavrilov@sgc-oc.com

S.E. Togaev, Reservoir Simulation Manager, Reservoir Engineering Department, Surhan Gas Chemical Operating Company» LLC
47 Bunyodkor Ave., Tashkent, 100161, Uzbekistan
E-mail: shorekh.togaev@sgc-oc.com

A.G. Klevitskiy, Geology Manager, Geology and Geophysics Department, Surhan Gas Chemical Operating Company» LLC
2 Universitetskaya St., Tashkent, 100161, Uzbekistan
E-mail: aleksandr.klevitskiy@sgc-oc.com

For citation:

A.V. Gavrilov, S.E. Togaev, A.G. Klevitskiy Integrirovannyy podkhod k opredeleniyu parametrov dvoynoy sredy na etape razvedki karbonatnogo mestorozhdeniya [An Integrated Approach for Dual-Medium Characterization at Carbonate Field Appraisal Stage]. Neftyanaya Provintsiya, Neftyanaya Provintsiya, No. 1(45), 2026. pp. 55-75. DOI https://doi.org/10.25689/NP.2026.1.55-75. EDN ZPJUJV (in Russian)

© Non-governmental organization Volga-Kama Regional Division of the Russian Academy of Natural Science, 2015-2026 All the materials of the journal are available under the Creative Commons Attribution 4.0 License (https://creativecommons.org/licenses/by/4.0/)

An Integrated Approach for Dual-Medium Characterization at Carbonate Field Appraisal Stage A.V. Gavrilov, S.E. Togaev, A.G. Klevitskiy DOI: https://doi.org/10.25689/NP.2026.1.55-75

Key words: naturally fractured reservoir, fracture void compressibility, interference testing, dual porosity, Surkhandarya oil and gas region

An Integrated Approach for Dual-Medium Characterization at Carbonate Field Appraisal Stage

A.V. Gavrilov, S.E. Togaev, A.G. Klevitskiy
DOI: https://doi.org/10.25689/NP.2026.1.55-75

Key words:

naturally fractured reservoir, fracture void compressibility, interference testing, dual porosity, Surkhandarya oil and gas region