ABSTRACT
Qingzang Plateau lies on the east part of Tethys tectonic-sedimentary domain. Four major evolutionary phases that have undergone since late Proterozoic, namely, Proterozoic Ocean, paleoTethys, neoTethys, and Indian Ocean, resulted in the formation of polyphasical basin and the composite and superposition of different prototype basins in different tectonic position within the plateau, and thus many potential oil-bearing regions were developed. Intense compression and complex basin deformation initiated from Pliocene complicated the generation and preservation of hydrocarbons. An important exploration question is whether hydrocarbons previously generated are efficiently preserved or not,and hydrocarbon accumulations are valid or not, where to identify the relatively stable tectonic units. Served as the examples, Lunpola Tertiary terrestrial basin and Qiangtang Mesozoic residual marine basin are two important oil-gas exploration regions in Qingzang plateau. Qingzang plateau is an important part of paleoTethys domain which was located between paleoEurasia and Gondwana. Explortion activities to date have discovered many significant hydrocarbon accumulations in the sedimentary basins of Tethys tectonic belt in varying degree( 1 ). Compared with the basic geology conditions and oil-gas-forming geology conditions of other basins in Tethys, Qingzang plateau is quite different and exhibits unique styles. However, the success in the exploration of petroleum conducted in the adjacent basins illuminates the prospects of hydrocarbon exploration in Qingzang region, and gives many examples and models for comparative study of basins.
