Study On Sedimentary Microfacies Of Lower Segment Of Minghuazhen In BZ25-1S Oilfield

Based on core,well logging,seismic,heavy mineral etc datum of lower segment of minghuazhen of BZ25-1S oilfield,taking sedimentlogy,lithology,Logging study,sequence stratigraphy,structural geology,petroleum geology etc theories as its instrument,and adopting sublayer comparison method of"cycle comparison, grading control",this thesis carried out research on the sedimentary microfacies characteristic,and summarized sedimentary evolution pattern of this area.We held this area as delta plain deposition system and the source direction westsouth.Slight calcic claystone with color changing from reddish brown,yellow brown to grey green are developed;rock particles are medium sand to fine sand,moderate to well sorted,mainly subrounded-subangular,lineation,unitary rock type;deposition developed trough cross stratification,tabular cross stratification,wegde cross stratification,obique stratification,parallel stratification,wavy bedding,massive bedding,downwash,top caliche nodule ect;four microfacies including branch channel,natural levee,crevasse splay and interchannel ; the channels displayed two forms of banding and lensing separately corresponding to different microfacies array;indicate the influence of the microfacies on the physical property of the reservoir,offer an definite foudation for the forecast of the lower segment of minghuazhen reservoir.Microfacies Types and their distribution are in control of producing liquid water from the oil wells and in control of water movement underground, Therefore to use the research results of Sedimentary microfacies to pinpoint the oil-rich region and enhanced oil recovery could play better results.