Abstract: The mid-segment of foreland thrust belt in southern Junggar basin is the key area of interest for exploration of the whole basin. Comprehensive study shows that oil and gas in this area is characterized by proximal and near-faulting distribution as well as late accumulation. The main factors for controlling the petroleum accumulation are source-communicated faults and reservoir rocks. It is suggested that there exist two models of petroleum accumulation such as above source rocks-anticline-faulting-facies control and proximal distribu-tion-faulted anticline-faulting control. The related comparison indicates that in the second and third rows of anticline structural zones, thefavorable area of interest for further petroleum exploration would be the middle reservoir combination, which is of significance to guide the petroleum prospecting efforts in southem margin of Junggar basin.

Key words: Junggar basin, south, foreland basin, petroleum distri bution, petroleum accumulation, reservoir forming, model