The Analysis Of Sedimentary Facies And Architecture Of Moliqing Fault Depression Of Yitong Basin

Located in southern Yitong graben,Moliqng fault depression is the southernmost second-order fault basin.Owing to a rapid accumulation of near source as well as complicated fault system,it's difficult to conduct stratigraphic correlation,sedimentary facies recognition and sedimentary architecture of dense well network.Under the guidance of the sedimentary petrology,seismic sedimentary,logging geology,reservoir geology and development geology,taking Shuangyang Formation Moliqing fault depression for example: Making extreme use of logging,seismic data in the well region to bring about stratigraphic correlation and building up fine isochronous frameworks;By means of core facies,log facies and seismic facies to determine the main source direction of the research area and realize the planar spreading of sedimentary facies;Architecture analysis of Moliqing fault depression,especially on single channel level,should be carried out by core data,logging data and connecting-well profiles.Shuangyang formation can be divided into three groups,one of which can be subdivided into 10 members.Moreover,member can be divided into top member and bottom member.On the base of isochronal stratigraphic framework,analyzing the core facies and logging facies of each well can ensure the sedimentary type and characteristics of Shuangyang formation as the research area,which develops three main types of sedimentary facies.Three main type of sedimentary can be called fan delta,near-shore underwater fan and deepwater turbidite fan.Their scale and syntagmatic relation are not as same as each other in different periods.In dense well network,the architecture analysis of S2-IV of deep-water turbidite fan determines four microfacies,which are braided channel,leafy sandbody,lateral margin of leaf sandbody and interchannel mud.The scale and syntagmatic relations of microfacies on well section can be further established.