Abstract:

The middle-upper Proterozoic in Hebei-Liaoning depression covers an area of about 70,000 km²,and is composed mainly of carbonates.A lot of oil shows have been found within the depression.According to the type and abundance of organic matters there,it is sugges-ted that the Gaoyuzhuang,Wumishan,Hongshuizhuang,Tieling and Xiama-ling Formations are all capable of generating hydrocarbons,but the most favour-able source-reservoir-cap assemblage are the Hongshuizhuang,Tieling,Xiama-ling Formations.The maturity of organic matters vary with places.At pre-sent,organic matters in Jibei,Liaoxi and Xuanlong depression are in a status of matured stage,those in Jizhong depression have reached highly matured to wet gas stage,while others in the other basins are in over-matured stage.According to the study of Shuangdong anticline,it is believed that oil was formed mainly in the periods of Indo-China and Yenshan movements.Finally,oil promising areas in the middle-upper Proterozoic are suggested in this paper.