GEOMECHANICZNA OCENA MASYWU SKALNEGO DLA POTRZEB BEZZBIORNIKOWEGO MAGAZYNOWANIA GAZU ZIEMNEGO NA PRZYKŁADZIE PMG SWARZÓW

Abstract

GEOMECHANICAL EVALUATION OF ROCK FORMATION FOR DEPLETED GAS RESERVOIRS – EXAMPLE FROM THE SWARZÓW UNDERGROUND GAS STORAGEAbstract. The Swarzów natural gas deposit is located in the Carpathian Foredeep. Its localization and geological structure facilitated the development of underground gas storage with desired parameters within the exhausted Mesozoic natural gas reservoir. The paper presents the results of engineering-geological studies on the rocks, forming the storage horizon, as well as the supra-storage and sub-storage horizons in the Swarzów underground gas storage. The samples for laboratory analyses were collected from the Swarzów-24, Oleśnica-2 and Oleśnica- 3 wells. Evaluation of mechanical properties of rocks necessary for geomechanical characterization of rock formations in the gas deposit included: measurements of uniaxial compressive strength on regular samples and point load methods, and tensile strength with the compression method. These parameters were then used for calculations of fracturing pressures for the storage, supra-storage and sub-storage horizons during injection and withdrawal of gas. The calculations aimed to determine if the exploitation of underground gas storage does not cause the fracturing of rock formations.