Active Characteristics Of Strike-slip Faults In Tahe Area Of Tarim Basin And Its Petroleum Geological Significance

The Tahe area is located in the middle-south of Akekule Uplift in Tabei Rise of the Tarim Basin.It is widely developed with strike-slip fault-related structures and is an important oil and gas exploration block in the Tarim Basin.In this paper,mainly using high-precision 3D seismic data and single well cumulative production well group data in the study area,the method of fine structural analysis of strike-slip fault system and analysis of single well cumulative productivity well group data for 1057 single wells are studied.The geometry,kinematics and dynamics of strike-slip faults,and the controlling effect of main and secondary strike-slip faults on oil and gas accumulation is discussed.The study shows that:(1)the development of the strike-slip fault system in the Tahe area has deep and shallow layering characteristics on both the coherent plane and the seismic profile;(2)the deep layers mainly develop NNE trend and NNW trend high-steep or near vertical main strike-slip faults,and NNE trend,NNN trend and near EW trend high-steep or near vertical secondary strike-slip faults;the shallow layers develop a large number of a single NNW trend and NE trend,the overall NNE trend distribution and a single NNE trend and NW trend,the overall NNW strike distribution of echelon normal faults,indicating the strike-slip direction of the underlying main strike-slip fault in different periods.(3)The strike-slip fault system in the eastern Tahe area has experienced at least three stages of the Caledonian-middle and late Heixi period,the end of the Hexi period activities,while the strike-slip fault system in the western Tahe area has experienced at least three stages of the Caledonian-Hercynian period,Indosinian period and Himalayan period activities.(4)The distribution of high-efficiency wells is closely related to the main and secondary strike-slip faults.The activity of the main strike-slip fault in the Himalayas has an important impact on the migration of oil and gas,and the secondary strike-slip fault has an important impact on the transformation of the Ordovician carbonate reservoirs.That is,the main strike slip fault and the secondary strike slip fault both play an important role in controlling the hydrocarbon accumulation.