The Prediction For Favorable Reservoir Distribution In Tight Reservoir In Es₁^x Of Lixian Slope Of Raoyang Depression

This issue derives from the cooperative project between China University of Petroleum(East China)and Huabei Oilfield of China National Petroleum Corporation.Lixian Slope is the secondary tectonic unit in RaoYang Depression,and is rich in oil and gas resources.But now the characteristics and the main controlling factors of tight reservoir are not clear,which restricts the development in research area.To solve these problems,we carried out the research about reservoir prediction.According to numerous literature,this paper made a conclusion about the research area situation and tight reservoirs at home and abroad.In addition,this issue made a comprehensive analysis and evaluation from three aspects: sedimentary characteristics,diagenetic characteristics and reservoir microscopic characterization.According to core observation,cast sheet,mud logging and well log data,we determined the type of sedimentary facies,diagenesis and pore throat types in the study area.And on this basis,combining with the reservoir physical property,we determined the main controlling factors for the development of density reservoir.Both sedimentary characteristic and diagenetic characteristic played very important roles in the development of reservoir.From a macro perspective,sedimentary characteristic governed reservoir characteristic.While the diagenesis modified the reservoir physical property at the later stage.Among them,compaction and cementation decreased porosity,but corrosion increased the porosity.Based on the throat radius,porosity and permeability,we classified the reservoir into four types: conventional reservoir,dense reservoir type I,density reservoir type II and non-reservoir.The research shows that Lixian Slope developed limited unconventional resource under the background of conventional reservoir.It is hard for us to predict the distribution of different reservoir types exactly.Given this reality,we combined with the reservoir influencing factors,and the distribution of hydrocarbon source rock,overpressure and fault,we predicted the favorable area of the density reservoir in research area.Based on the above research,we concluded that the advantageous area of dense oil main developed in the area near depression and the deeper secondary pore development area,which proved that Xiliu region is exactly the favorable area.