Sedimentary Facies Study for IV Sand Group of the Second Member of Qingshankou Formation in Daqingzijing Area

Sedimentary microfacies of Ⅳ sand group of the second member of Qingshankou formation in Daqingzijing area are interpreted jointly with careful core description, sequence and distribution of sandstone. The area also develops delta. Sedimentary microfacies shows that sand body size is becoming smaller and in the transgression period of Ⅳ sand groups of the second member of Qingshankou formation in the region. Sedimentary center has better properties, and the lateral margin of sand body is easy to form lithologic reservoir.