关键词: 库车坳陷, 秋里塔格褶皱带, 断层相关褶皱, 断坡, 油气圈闭, 变形序列

Abstract: The Qiulitag anticline zone is the thrust front of the Kuqa thrust-and-fold belt along the southern piedmont of Tianshan Mountain. The data of surface geology, two-dimensional seismic reflection profiles and stereoscopic remote-sensing measurements were integrated and used to construct the balanced geologic cross sections and define the subsurface fault and fold geometry. These approaches provide insights into fold-and-thrust belts, where subsurface data are limited. The shape of the thrust faults underlying Qiulitag anticline was controlled by the architecture of the rift basin. The ramp height of the deep fault system was declined from three kilometers in the east regional cross section to one kilometer westward, where an imbricate fault was developed. A three-dimensional geometrical and kinematical model was constructed, and the deformational mechanism was analyzed. The different structures in eastern and western Qiulitag anticline zone resulted in the different types of traps, which controls the hydrocarbon accumulation in the Qiulitag anticlinge zone.

Key words: Kuqa area, Qiulitag anticline zone, fault-related folds, fault ramp, hydrocarbon trap, deformational sequences