Study on reservoir heterogeneity of clastic rock of Shahejie formation in Dongying sag

Seven kinds of sandbodies from different genetic types have been developed in Shahejie formation of Dongy- ing depression and the reservoir heterogeneity of them is obvious.Through the research on physical parameters of core analysis and log interpretation,the reservoir hetero- geneity in Shahejie formation is found to be mainly con- trolled by sedimentary microfacies and diagenesis.The distribution of porosity and permeability is varied both at different intervals and different structure positions of the same interval.Vertically,preferable reservoirs are dis- tributed in Es2,middle Es3 and upper Es4.Horizontally, several sets of superposed reservoir assemblage are dis- tributed in Bamianhe oilfield situated on gentle slope in the south,and Shengtuo oilfield,Binnan oilfield,Dongxin oilfield and Yong'anzhen oilfield which are situated on steep slope in the north.