Study On Sedimentary And Reservoir Characteristics Of Chang2Formation In Gaojiagou-qingyangcha Area

The paper is summarized in many of predecessors’ achievements，and on the basis ofpetroleum geology，tectonic geology，sedimentary petrology，logging geology and relateddiscipline theory as the guide，the comprehensive utilization of the study area logging data，drilling material, oil test material and the core analysis test data of study area，finished thesmall member division and correlation of Chang2，sedimentary facies and sand distribution，reservoir characteristics and reservoir evaluation research， in order to obtain comprehensiveand systematic knowledge of sedimentary and reservoir characteristics of Chang2formation．The results of the study show that Chang2formation can be subdivided into Chang21，Chang22and Chang23．The sedimentary facies of Chang21is meandering river，and themicrofacies include riverway and flood plain.The sedimentary facies of Chang22and Chang23is braided river, and the microfacies include underwater channel bar and flood plain．The mainreservoir rock types are feldspar sandstone，mainly is fine particle size，and fairly well sorted，the pore type is mainly primary intergranular pore，followed is dissolution pore，target area islow-permeability．Reservoir inner of layer and plain heterogeneous is strong， interlayerheterogeneity is relatively weake．Reservoir classification results show that major Ⅱclass isgiven priority to Chang21member，followed is Ⅲ class;major Ⅱclass is given to Chang22member, reservoir evaluation is better; major Ⅲclass is given priority to Chang23member，followed is Ⅱ class，reservoir physicial properties is double controlled by sedimentation anddiagenesis.The study on the sedimentary and reservoir characteristics of Chang2Formation inthis paper provides reasonable geological basis for further exploitation.