Study Of Sedimentary Characteristics And Reservoir Evaluation Of Shahejie Formation In The Western Depression Of Liaohe Basin

Looking for the favorable reservoir is one of the key problems facing in oil and gas explor-ation of the northern Xinglongtai Oilfield in the western depression of Liaohe basin. Based on the division and correlation about formation, we study sedimentary characteristics and evaluate-physical property of the reservoir of the lower part of Member 1 of Shahejie Formation system-atically to provide important geological basis for finding out the oil and gas reservoir in study area with Xing 20 area of Xinglongtai oilfield as the objecet of the research. The result shows that the lower part of Member 1 of Shahejie Formation of Xing 20 area is a set of coarse clastic sediments which is mainly composed of glutenite, conglomeratic sandstone and whose composition and structure maturity is low and it could be divided into 12 sandstone groups.44 small layers. It. The distribution characteristics of each thin layer sandstone is similar, irregular fan. becoming thinner from the northeast to the southwest.The sedimentary is from of the northeast of the depression. The lower part of Member 1 of Shahejie Formation of Xing 20 area is fan delta front subfacies which contains four types of microfacies:distributary channel microfacies, river mouth sandbank microfacies, frontal sheet sand microfacies and interdistribut-arybay microfacies.The distributary channel microfacies is main sedimentary type, river mouth sandbank microfacies and the frontal sheet sand microfacies is the second one. The study about evaluation of reservoir shows that the physical properties of small layers are mainly affected by sedimentary, and the physical properties of sand of distributary channel microfacies are relatively well. The distribution of the physical properties of each small layer is similar and the northeast is better than the southwest mostly.