Effect of Fault on in-Situ Stress Perturbation in Deep Carbonate Reservoir
The existence of faults in deep carbonate reservoirs is characterized by the complex stress field near faults, which has a great influence on the extension of induced fractures and the formation of the fracture network. In this paper a numerical procedure is proposed for the regional boundary stress determination. Fault zone properties were defined by measurement of the samples and were further verified by comparing the calculated stress values with the measured values for the fault zone. The change in the principal stress value and orientation and the perturbation area were quantified. The authors analyzed the boundaries of the areas at the ends of the fault where the horizontal principal stress difference increases and decreases symmetrically. The influence range increases with the increase in the fault length. The stress concentration determined by the fault structure increases or decreases markedly in the area near the fault tip.
Keywordsfault in situ stress: local stress destabilization: hydraulic fracturing
This study was supported by National Natural Science Foundation of China (Grant No. 51674044), National Science and Technology Major Project (No. 2017105005-005-004), and Project of the Ministry of Science and Technology of Sinopec (P17004-2). Also, we would like to thank Sinopec Northwest Company for providing the measurement data and geotechnical parameters.
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