ON THE TYPE OF THE YINING BASIN AND ITS SIGNIFICANCE OF PETROLEUM GEOLOGY

Three stages of tectonic evolution for Yining composite basin are distinguished:Carboniferous early Permian,late Permian and Meso-Cenozoic,correspondingly three prototype basins,i.e.an intra-arc basin,an intra-arc remnant basin and intermontane basin dynamically dominated by distal collision were successively formed.The intra-arc basin is a typical extensional basin,and the intra-arc residual basin is attributed to a depressed basin resulted from the cooling shrinkage of the mantle,both with developed source rock series.The distal-collisional intermontane basin is a compressive basin,with poor developed source rocks.Therefore the former two basins have a promising prospect for oil-gas exploration