Correlation And Sedimentary Facies Analysis Of The First And Second Member Of Shahejie Formation In Gubei Sag Stratigraphic

In this paper,through collecting and analyzing a large number of drilling data,core data and logging data,according to the theory of high-resolution sequence stratigraphy and sedimentology theory as a guide,establish high-resolution sequence stratigraphic framework,the solitary northern sub-sag,has carried on the first and second section stratigraphic correlation,the types of sedimentary facies,sedimentary system characteristics,the types of sand body.The first and second members of the Shahe Formation are divided into one medium and long term base-level rising semi-cycles and two medium term base-level rising semi-cycles.Regional stratigraphic correlation is carried out under the control of datum cycle.Solitary northern sub-sag,sand area,two period sedimentary basin development system,multiple source by logging data,and draw the sandstone thickness,ratio of sand,and carbonate rock thickness isoline maps,think in two sedimentary period,solitary double provenance areas in northern sub-sag of supply,mainly composed of buried hill and long beach,on the east side of the island in the south of bump,pile in the north of west buried hill with a small amount of material sources.During the sedimentary period of the first member of Shahejie,the provenance was mainly provided by the island uplift in the south.A solitary northern sub-sag,sand,second time various types of sedimentary facies,and given priority to with traction current deposits,a small amount of gravity flow,the main development of the delta(delta)()of fan delta front,fan delta,lake,shore and shallow lake and deep lake-half deep lake),beach dam dam(sandy beach,carbonate bank dam)as well as the slump turbidite fan and so on five types of sedimentary facies.Delta and fan delta were the main sedimentary facies types in the second member of the Shahejie Formation,and the slump turbidite fan developed in the front segment of fan delta front in the north of the eastern subsag.In the sedimentary period of the first member of Shahe1,the supply of provenance was less,and the sedimentary facies of shore-shallow lake,carbonate beach bar and sandy beach bar were mainly developed.There are various types of sedimentary systems and reservoir sand bodies in the first and second member of Shahejie Formation in Gubei Sag.According to their origin,the reservoir sand bodies can be divided into three types: delta sand body,fan delta sand body and beach bar sand body.According to the well logging curve,the structure can be divided into six types: ?type and normal type.The favorable reservoirs are mainly controlled by sedimentary facies,and delta front and fan-delta front sand bodies are considered as favorable reservoirs,followed by carbonate beach bar sand bodies.Sandbodies of delta front and fan delta front are mainly developed in the second member of Shahe Formation,and carbonate beach bar and sandy beach bar are more developed in the first member of Shahe Formation.