The Sedimentary System Of Es₄-Es_3x Member Of Shahejie Formation On The Southern Slope Of Dongying Sag

During Eleventh Five-Year period, oil and gas proved reserves can reach to186milliontons and214million tons of controlled reserves as well as168million tons of controlledreserves in the southern slope of Dongying Sag recently, even in the near future the mainincreasing reserves and favorable reservoir still develop in Es₄-Es_3x。We can divide the formation by using group and segment to establish the stratigraphicframework,analyzing the summary logging,seismic data,and summarizing the identifiedcharacteristics of the formation interface. Stratigraphic division based in the theory under theguidance of the sedimentology,logging geology and other disciplines,in terms of lithology,rock type, rock color,grain size characteristics,sedimentary structures,logging features,seismiccharacteristics,the study District relative to sign a systematical summary,and investigates thetype of depositional system in the study area. alluvial fan,delta,fan delta, beach bar,turbiditefan,semi-deep lake-deep lake sedimentary system are the main development in the southernslope of Es₄-Es_3x in Dongying Sag.Based on types of the sedimentary facies and characteristics,using the point-line–planeidea and the analysis of the key core established wells combined with glutenite thickness,percentage content,we can depict planar distribution range,the distribution characteristics ofthe depositional system in Southslope of Dongying Depression. That alluvial fan depositionalsystem developed in Es4,together with beach bar deposition systems of shallow lake in Es4cxand Es4cs as well as Delta and turbidite deposition system in Es3x. At the same time, weexplore the evolution of depositional systems in the longitudinal direction.In addition, the combination of previous research results, analysis of the controllingfactors of the deposition system, the distribution and evolution of depositional systems ofEs₄-Es_3x in the southern slope of Dongying Depression are mainly controlled by tectonics,climate, the ancient geomorphologicalinfluence and control of other factors, especially the ancient geomorphological played a very important role in aspects of the beach bar systemdevelopment, distribution and scale.