The Sedimentary Facies And Reservoir Characteristics And Fine Description Of The Paleogene Dongying Formation,in JinZhou 9-3 Block

The sedimentary study area is JingZhou 9-3 Block LiaoDong sag,Bohai Bay and the study focuses on Paleogene DongYing formation,a delta front sedimentatry deposite system.The fine division of the formation was based on the integration of multiple datasets,which include core,logs data,rocky cuttings and seismic.After incorporating the data from new wells,we got an improved understanding on the exact structure and faults.With the application of the principle of sedimentary,sequence stratigraphy and reservoir description,the distribution of hydrocarbon and geology charcters were defined.With the application of fine correlations method,the target interval was subdivided into 11 sand groups,41 layers.2 major marker beds,2 sub marker beds and 2 minor faults were identified.Based on the correlation of well and seimic data,the exact structure of each main reservoir and 25 faults were identified.Based on the study on the fluid system and the structure evaluation,it is concluded that the distribution of the reservoir is controlled by major faults and associated minor faults.With the constrain of fine stratigraphic framework,we have analized the sedimentary facies,reservoir characteristics and fine description of Dongying Formation.Five sub facies were identified which are submarine distributar channel,mouth bar,distal bar and sheet sand,intermediate clay.The main reservoirs are an amalgamated sand of sub channels and mouth bars.The lithology type,property distribution and heterogeneity were also researched using thin section,SEM,mercury intrusion and so on.The distribution of sand thickness and interbeded claystone within the amalgamated reservoir sandbody were delieneated.The distribution of the main reservoir and the potention opportunities were captured.The key subsurface uncertainties impactting HIIP were identified by Monte Carlo method and sensitivity analysis.After screening out the key uncertainties of the reservoir,detail design on the model low case,base case,high case was decided.The comparison of Hydrocarbon resource volume between probability function modelling calculating method and static modelling method can be used to quantify the uncertainty range on resource volume and support the decision on further development of the feild.