Fault characteristics and its control on hydrocarbon accumulation in Xianbazha area of Markit Slope, Tarim Basin

Based on the interpretation of 3D seismic sections, strike-slip faults were widely developed in Xianbazha area besides thrust faults. The faults appeared in different layers and overlapped in the space. The evolution of the faults experienced three stages including the middle Caledonian, the late Hercynian and the Himalayan. The faults played an important controlling role in oil and gas accumulation. The small thrust faults in the middle Caledonian were conducive to karst reservoirs as passageways of meteoric fresh water, and the strike-slip faults in the late Hercynian were favorable to reservoir reconstruction for deep thermal fluid. The Xianbazha fault controlled the development of trap in the upper Paleozoic. The strike-slip faults were favorable to oil and gas aggregation in the upper Paleozoic and restricted oil and gas accumulation in the Ordovician as vertical migration pathways.