库车褶皱冲断带断裂、构造对油气藏的控制作用

充分认识库车褶皱冲断带断裂、构造在油气成藏过程中的作用，将有助于该区和中国西部相似地区的油气预测和勘探。依据断裂的力学性质，分类探讨了该区的断裂及其伴生构造对油气藏的控制作用。在强烈活动时期，断裂均具有疏导功能；在相对稳定时期，断裂的控藏作用随断裂力学性质变化。挤压型断裂以封闭作用为主，相关的圈闭构造有逆断层下盘背斜、逆断层上盘伴生背斜和滑脱层下盘风化壳等；走滑型断裂以垂向疏导和侧向阻隔的双重作用为主，相关的圈闭构造有花状构造和雁列背斜，其中最利于油气聚集的位置是雁列背斜远离断裂的一端和弧形断裂内侧；伸展型断裂以疏导作用和改善储集性能为主，相关的正牵引背斜和反向抬斜断块是钻探成功率最高（接近100%）的圈闭构造。库车褶皱冲断带“封存箱”的实质是断裂构造封存，挤压型和走滑型断裂作为封存箱的顶底板和侧板。

CONTROL OF FAULTS AND ASSOCIATED STRUCTURES ON RESERVOIRING IN KUQA FOLDED THRUST BELT

A thorough understanding of the functions of faults and their associated structures in oil and gas reservoiring in Kuqa folded thrust belt is helpful to prediction and exploration of oil and gas in the study area as well as similar areas in East China. The control of the faults and their associated structures on oil and gas reservoiring in the study area is discussed based on their mechanical properties. All of the faults acted as pathways during intensive faulting, while the control of faults on reservoiring depended on their mechanical properties. The compressional faults mainly acted as seals, and the relevant structural traps include footwall anticline of reverse fault, hanging wall associated anticline of reverse fault, and footwall weathering crust in detachment fault. The strike slip faults acted vertically as pathways and laterally as seals, and the relevant structural traps are flower structure and en echelon anticline, with the distal ends of the en echelon anticlines from faults and the inner side of arc faults being most favorable for hydrocarbon accumulation. The extensional faults mainly acted as pathways and improved reservoir properties, and the relevant normal drag faults and reverse tilt fault blocks have the highest drilling success rate of almost 100%. The compartment in Kuqa folded thrust belt is interpreted to be fault seals and the compressional and strike slip faults act as the top and bottom panels and lateral panels, respectively.