Reservoir Evaluation And Prediction Of Chang 3 Member In Zhenbei Area

Based on the comprehensive research and understanding of the reservoir of Chang 3member in Zhenbei area of Ordos basin by predecessors,this paper takes 9 small layers of Chang 3 member reservoir as the research object,and through conventional analysis and testing methods such as field outcrop,core,logging interpretation data,casting thin section,scanning electron microscope and measured physical properties,etc The microscopic pore structure and diagenesis of the reservoir are analyzed in depth.The reservoir of Chang 3member is mainly affected by the southwest provenance,and develops braided river delta sedimentary system.The braided river delta plain subfacies sedimentary system is mainly developed in the west of the study area,and the braided river delta front sedimentary system is developed in the east.The rock type is mainly feldspar lithic sandstone,with residual intergranular pores and feldspar dissolution pores as the main pore types,followed by intergranular dissolution pores.Its pore structure has the characteristics of fine pores and fine throats.The porosity,permeability,and pore structure of the Chang 3 reservoir exhibit a gradual improvement from bottom to top.Constructive diagenesis includes dissolution and early chlorite coating to protect particles.Destructive diagenesis mainly includes early mechanical compaction and later clay minerals cementation.Combined with the distribution of sedimentary facies belt,the development of channel sand bodies,reservoir porosity,permeability physical characteristics,pore structure types,diagenesis,distribution of diagenetic facies belt and other comprehensive factors,the reservoir evaluation and classification of Chang 3 member reservoirs in Zhenbei area were carried out,and the distribution characteristics of different reservoir types in the plane are clarified.