南堡1-5油藏改建储气库断层承压能力评价OA

The primary risk associated with repurposing complex fault-block oil reservoirs into gas storage facilities lies in the potential loss of fault seal integrity under alternating high and low pressure conditions during cyclic injection and production.Therefore,a quantitative assessment of the pressure-bearing capacity of faults is critical to ensuring the safe operation of such gas storage sites.This study,based on seismic data,drilling records,and production dynamics from the Nanpu 1-5 Reservoir,conducts a graded and staged evaluation of faults.Through four-dimensional geomechanical simulations covering the entire lifecycle of reservoir development and gas storage injection-production operations,the safe pressure-bearing capacity of faults is quantitatively evaluated.The results indicate that faults F1 to F6 generally exhibit large throws,characterized by sealing inter-faces between gas-bearing layers and tight formations,demonstrating excellent sealing performance.The Nanpu 1-5 Reservoir is divided into four fault blocks:NP1-7,NP105X1,NP1-5X1090,and NP105X5.Critical weak points in these fault blocks are identified as boundary faults F2(NP1-7),F2(NP105X1),F5,and F6,with safe pressure-bearing capacities of 27.4,28.9,28.9,and 27.5 MPa,respectively.These findings provide a scientific basis for optimizing the maximum operating pressure of the NP1-5 gas storage facility.The methodology can be extended to enhance the operational efficiency of existing gas storage facilities through pressure optimization.