The thrust fold belt in southern margin of Junggar basin has been still active since the Cenozoic era, and the hydrocarbon exploration in this area must focus in present thrust structural belt rather than ancient one. Based on available surface surveys and 2D/3D seismic data interpretations, the dip angles of thrust faults in this belt most range from 30°±5° to 50°±5°. The stress analysis shows that intersection angle between the principal stress and the fault is about 30°±5°, which means the maximum/the minimum principal stress ratio is the mini- mum, there exists the maximum fluid pressure, at which the fluids around the fault may flow along the maximum principal stress orientation, the faults become the main pathway of fluid migration. When the intersection angle is about 50°±5°, the reactivated faults need higher fluid pressure, resulting in that the sealing of the fault is relatively better. Under the tectonic compression, the thrust fault extends toward the north, in which the detachment layer of fault is mudstone or shale of the Paleocene Anjihaihe formation, which forms much higher tectonic overpres- sures in this layer. The sandstone horizontal permeability of the Ziniquanzi formation underlying Anjihaihe formation is much higher than its vertical permeability, which is helpful to becoming favorable reservoirs, being major target zones for petroleum exploration in this area.%准噶尔盆地南缘逆冲褶皱带为新生代以来一直活动的逆冲构造带，因此该地区的油气勘探必须以此为重点而非古逆冲带。据地面地质、地震和钻井数据分析，准南逆冲带的逆冲断层倾角主要集中在30°±5°和50°±5°．应力分析表明，主压应力与断层为30°±5°夹角，最大主应力与最小主应力比最小，表明存在最大的流体压力，断层周围的流体沿着最大主应力方向发生流动，断层成为流体运移的通道。而为主压应力与断层倾角在50°±5°夹角时，断层重新活动需要更高的流体压力，导致断层封闭性相对较好。准南逆冲褶皱带在构造挤压作用下逆冲断层向北扩展，作为断层滑脱面的古近系安集海河组泥岩形成更高的构造超高压，同时造成安集海河组之下紫泥泉子组砂岩水平渗透性远大于垂直方向渗透性，可以发育有利储集层，成为南缘地区主要勘探目的层。
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