Study On Distribution And Connectivity Characteristics Of Glutenite Reservoir In Es3-es4 Member Of Yong920-921 Area

Yong 920-921 area is the key development block of glutenite reservoir in Yanjia oil field in Dongxin area of Dongying depression.The proven oil-bearing area of glutenite of Es3-Es4 member in Dongxin area is 25.81km~2,and the area to be proved is 128.97km~2,which has broad exploration and development potential.The recognition of reservoir distribution and connectivity characteristics is the geological problem to be solved for efficient exploration and development of oil and gas.In this paper,the glutenite reservoir of Es3-Es4 member in yong920-921 area is taken as the research object.In view of the research status of glutenite reservoir with strong concealment,fast reservoir change,difficult reservoir identification and description,and unclear connectivity,the research on glutenite stage division and spatial distribution,glutenite reservoir distribution and connection body identification and description is carried out under the guidance of sequence stratigraphic division.It provides a theoretical basis for the optimization of favorable zones in the process of development.Guided by the theory of high-resolution sequence stratigraphy,using the core,drilling,logging and 3D seismic data,the sequence framework is established and the periods are divided.Through the identification of cycle conversion surface,the fine stratigraphic division and correlation of glutenite are carried out in the way of point,line and surface research.The lower Es3 sub member and the upper Es4 sub member of glutenite in the study area are divided into 7 periods and 6 periods.The spatial distribution of glutenite in different stages is characterized by vertical retrogradation.Combined with seismic facies and lithofacies,established the seismic facies model to guide the description and analysis method of glutenite reservoir,innovated the use of instantaneous phase sensitive attribute body to improve the accuracy of reservoir interpretation,established the recognition template of glutenite lithofacies,divided the plane lithofacies of glutenite into conglomerate facies,gravel bearing sandstone facies,gravel sandstone facies and mudstone facies,and determined the glutenite of lower Es3in yong920-921 area The main controlling factors of oil and gas accumulation are structural conditions,and the main controlling factors of oil and gas accumulation are reservoir physical properties.It is established that the sedimentary model of glutenite in the study area is mainly nearshore subaqueous fan deposition,and the functional relationship between seismic attributes and physical properties is established to carry out the plane prediction of reservoir physical properties.Based on the development practice,the auxiliary analysis of glutenite connectivity,the combination of reservoir plane distribution and prediction,trace integral inversion and structural conditions,and the comprehensive evaluation have confirmed the plane distribution of glutenite connectivity.There are 5 connectivity bodies of the lower Es3sub member in yong921 well block,and 4 connectivity bodies of the upper Es4 sub member in yong920 well block.According to the different main controlling factors of oil and gas accumulation in the study area,further fine implementation of tectonic conditions,identify lithologic boundaries and determin the favorable facies zones are carried out for structural-lithologic and lithologic-structural reservoirs.Determine the lower limit of physical property threshold,look for high porosity physical property and determine the lithologic boundary are carried out for reservoir controlled by glutenite lithology in the fan margin of the South and physical property difference in the fan root of the north.The micro high trap area in Yong 921-41 well block and the reservoir high porosity area without well control in Yong 920 block are the potential areas.