EVOLUTION OF OIL-GAS BEARING BASINS IN CHINA

Considering the crustal movements in various geologic periods and the deposition ancient geography in China, this paper comprehensively analyses the features of the evolution of continental oil-gas bearing basins in China since late-Palaeozoic era. It is concluded that the lake basins formed in the Permian period are placed in North Xinjiang; the lake basins formed in the late-Triassic period are placed in Shaan-Gan-Ning (Shaanxi-Gansu-Ningxia) area; in the Jurassic period the west part of China were subsided over an large area and therefore a lot of the large lake-basins with the greater water area were formed, and so, the lake basins of western China are more than of eastern China. After the early late-Cretaceous period, the west part of China was raising and the east part of China was subsiding. In the early late-Cretaceous peried the Song-Liao (Songhuajiang and Liohe rivers) basins were formed. In the early-Tertiary peried, the lake-basins such as Bohaiwan (Bohai Bay), Subei (Northern Jiangsu) Jianghan (Changjiang and Hanshui rivers) and continental slelvies in seas were formed.Above-mentioned large-scale ancient lake-basins all are favorable sites generating the petroleum oil and natural gas.