Abstract
Chinese Cenozoic sedimentary basins are divided into two basin groups by their tectonic feature and the geographical distributions. The divided line lies from Holan Shan (Ningxia Province) to Dashue Shan (Sichuan Province), via Liupan Shan — Longmeng Shan. Western Basins consist of Tarim Basin, Qaidam Basin and Junggar Basin etc. They are compressional basins and relatively vast basins in the area. Eastern basins are extensional (rift) basins, which are subdivided into three basin groups. They are Eastern Sea Coast Basin System, Eastern Basin System and Western Basin System. Eastern Sea Coast Basin System includes East China Sea Basin and Pearl River Mouth Basin etc. Eastern Basin System includes Sungliao Basin and Bohai Gulf Basin etc. Western Basin System includes Ordos Basin and Sichuan Basin etc.
It is estimated that around 90% of crude oil originated from non-marine source rocks.
Biomarker data from Qaidam Basin, Bohai Gulf Basin and Pearl River Mouth Basin have been interpreted. In Qaidam Basin, biomarkers indicate the existence of the hypersaline environment in the era of Oligocene and Miocene. Main source rock of Es3 (3rd member of Shahejie Formation) is abundant of non-marine algae in Bohai Gulf Basin. Biomarker data from Wenchang Formation and Enping Formation, which are main source rocks in Pearl River Mouth Basin, indicate that source material was deposited in the fresh water environment.
