Geochemical characteristics of oil and correlation of oil to source rock in ramp region of Wunan depression of Hailaer basin

The physical properties of ramp region of the Wunan depression oil are low density,low viscosity,high wax content and high freezing point;and its geochemical characteristics are high content of saturated hydrocarbons and low value of carbon isotope.It is mainly mature oil formed in the fresh water-brackish water environment.There is a high content of land-based plants and a certain content of aquatic plankton and algae in the parent materials of the oil. According to the group composition,carbon isotope and the biomarker data comparison of the oil and source rocks in the study area,draw the conclusion that the crude oil of the Tongbomiao group are mainly comes from the dark claystone of the Tongbomiao group;and the mother rocks of the Nantun crude oil are the dark claystone of the Nantun group and the Damoguaihe group;and the crude oil of the Damoguaiheer sector is a mixture of the mature oil which comes from the Nantun and Tongbomiao groups and the immature oil generated from the Damoguaihe group.