叠合盆地凸起区多期复杂断裂特征及形成机制——以准噶尔盆地车排子凸起为例

以高精度三维地震资料为基础,结合构造演化恢复和区域构造背景,系统研究了准噶尔盆地车排子凸起断裂分布和形成机制。结果表明,车排子凸起发育深部和浅部2套断裂体系,深部断裂体系和浅部断裂体系分别发育3种断裂样式。车排子凸起共经历5个构造演化阶段,其中,晚二叠世挤压-逆冲控制了深部断裂体系的初始形成,晚侏罗世逆冲-走滑控制了深部断裂体系的最终定型,新近纪叠加掀斜、局部伸展控制了浅部断裂体系的形成。不同断裂体系在油气成藏过程中均起到了重要作用。其中:深部断裂体系的红车断裂是重要的油源断裂,低序级断层控制形成了石炭系火山岩优质储集体;浅部断裂体系使得油气向浅部层系运移调整,同时形成了断块圈闭、断鼻圈闭和断层-岩性圈闭等丰富的圈闭类型。

Characteristics and formation mechanism of multi-stage complex fault system of uplift in superimposed basin:a case study of Chepaizi Uplift,Junggar Basin,NW China

Based on 3D high-precision seismic and associated with structural evolution and regional structural background,we systematically analyzed the distribution and formation mechanism of fault system in Chepaizi Uplift in Junggar Basin.The results show that two fault systems,deep fault system and shallow fault system,developed in the Uplift,and these two fault systems have three patterns respectively.The Chepaizi Uplift underwent five stages of tectonic evolution,among which three stages were critical:the compression-thrust of late-Permian determined the initial formation of deep fault system;the thrust-stike-slid of late Jurassic determined the final formation of deep fault system;the extention superimposed tilt of Neocene determined the formation of shallow fault system.Different fault systems play an important role in the process of hydrocarbon accumulation.The Hongche Fault of the deep fault system is an important source fault,the low-grade faults in the deep fault system control the formation of high-quality reservoirs of carboniferous volcanic rocks,the shallow fault system makes the migration and adjustment of oil and gas move to the shallow strata,and at the same time,it forms various trap types like fault block trap,fault nose trap,fault lithology trap,etc.