关键词: 西藏, 沉积, 构造, 地球化学, 油气生成, (措勤盆地)

Abstract: According to the sedimentation, structure and geochemistry of Cuoqin basin in northern Tibet, an analysis of characteristics of generating oil and gas from varied hydrocarbon source rocks is made. And a comprehensive evaluation permits to believe that it was sedimentary and structural evolution that controlled the development and spatial distribution of its hydrocarbon source rocks. The carbonate source rock with high thermal evolution and usual generation of gas is mostly located in Upper and Lower Paleozoic systems; undeveloped and limited source potential is found in Triassic and Jurassic; whereas in Lower Cretaceous presence of carbonate and muddy source rocks, with moderate thermal evolution and better source potential, provide major hydrocarbon source rocks in Cuoqin basin, the northeaster part of which will be the most favorable prospective area for finding oil and gas.

Key words: Tibet, Sedimentation, Strueture, Geochemistry, Oil and gas origin, (Cuoqin basin)