Sedimentary Characteristics of Tight Sand Reservoirs of Badaowan Formation of Baka Oilfield

In order to analyze clearly the sedimentary characteristics and reservoir variation of Badaowan Formation of main reservoirs of Baka Gas Fields,based on the analyses of the data of core,well logging and seismic,etc.,all kinds of facies markers including rock composition,lithology,argillite color,sedimentary structure characteristics,rock grains,logging curves and seismic facies,etc.) are indentified.Based on the study above,the types of main sedimentary facies,sub-facies and microfacies are determined.It is determined that Badaowan Formation mainly develops sub-facies sedimentary system in braid river delta plain,which can be further divided into 4 microfacies,namely,braided channel,abandoned channel,flood plain and flood plain swamp.Based the study results above,corresponding sedimentary facies mode is established,which sets a foundation for the development of gas reservoirs.