The Tight Oil Accumulation Model and Geological Characteristics in Continental Sedimentary Basins of China
The exploration practices in recent years confirmed that tight oil is widely distributed in continental sedimentary basins of China. Some significant discoveries have been obtained in Ordos basin, Junggar basin and Songliao basin, etc. At present the cognition degree about tight oils in China is still relatively low. This paper divided tight oil into four accumulation models, three matching relationships of source and reservoir and two reservoir types of sandstone and carbonate rock, according to the lake-level fluctuation and sediment supply, saline lacustrine basin depositional feature, development and disposition relationship of source rock and reservoir as well as tight reservoir lithology, etc. Also, this paper analyzed the geological characteristics of scale and physical properties of tight reservoirs, and discussed their significances for petroleum exploration for the purpose of providing references for China's continental tight oil exploration.