Research on the four-property relation and net pay cutoff thickness of 3rd member of Funing formation in Zhangjiaduo oilfield

The 3rd member of Funing formation in Zhangjiaduooilfield belongs to delta facies and the reservoir is mainly of fine sandstone and secondly of siltstone.Through reservoir lithology,well logging,testing,and a variety of testing data analysis,the research on the four-property relation of thetarget area has been carried out.The results believe that the 3rd member of Funing formation belongs to middle-low porosity and extra-low permeability reservoir,and the hydrocarbon enrichment degree is controlled by lithology and physical properties.Besides that,the reservoir physical property lower limit is determined,namely porosity of 13%,shale content of 22.0%,Interval Transit Time of 254 us/m,resistivity lower limit of 3.2Ω·m.Through the optimization of reservoir parameter quantitative interpretation model,the precision of reservoir parameter calculation is improved,avoiding the leakage of effective thickness.By using the testing method,the lower limit of reservoir oil saturation of the3rd member of Funing formation is 40%and the net pay cut-off thickness is 0.6 m.