Quantitative Research of Petroleum System of Xujiahe Formation in Southern Sichuan

Xujiahe formation in southern Sichuan consists of three structural units: Weiyuan- Longnusi uplift,artesian well depression and southern Sichuan ruche region with gentle construct,with tight reservoir and strong heterogeneity. From the point of oil and gas exploration,especial from the high- yielding well with the production of100 × 104m3d,it can be seen that lithologic trap of Xujiahe formation in southern Sichuan has great exploration prospect. Combining with reservoir sedimentary petrology,diagenesis and basin modeling technology,quantitative research has been processed for evolutionary process of Xujiahe formation in Southern Sichuan since Yanshan period. The evolution from Weiyuan- Qianwei uplift,to north,to east and to south are flat gradient,which make the hydrocarbon migrates to high position in reservoir dominant pathway. In the high point of structure,lateral sealing and accumulation has been happened for sediment microfacies change position. Sediment microfacies are the main controlling factor for Xujiahe formation. Strenthening the research of sediment microfacies with high resolution could help forecast and identification of oil and gas reservoir.