Characteristics Of Untabulated Reservoirs And Its Influence On Remaining Oil Distribution Of S,P And G Reservoirs In Xingliu Area,Daqing Placanticline

Conventional sandstone reservoirs of continental facies have generally entered the stage of high water cut development.It is an urgent problem to find favorable blocks and stabilize oil and control production in major oil fields.Untabulated reservoir is widely developed in Daqing placanticline.Laboratory experiments and mineral practice show that untabulated reservoir have potential for development.Therefore,untabulated reservoir have gradually become the focus of petroleum workers.In this paper,the independent untabulated reservoir in Xingliu area of Daqing placanticline is taken as the research object.By using core data,logging data and development data,the principles of sedimentology,geostatistics and reservoir engineering are applied to describe the petrological,physical and sedimentary characteristics of the independent untabulated reservoirs in the study area.On this basis,the control effect of different geological characteristics on the remaining oil is analyzed,and the factors with strong control effect on the remaining oil are selected as the classification parameters of independent untabulated reservoirs in the study area,so as to classify and evaluate the independent untabulated reservoirs.According to the remaining oil types and distribution characteristics of different types of independent untabulated reservoirs,the potential of different types of independent untabulated reservoirs is analyzed.The higher the oil displacement efficiency,the stronger the water flooded degree.The higher the water flooded ratio,the stronger the utilization degree.The results show that the key factor affecting the oil displacement efficiency of independent untabulated reservoirs in the study area is permeability,while other factors have weak control on oil displacement efficiency.According to the permeability,the independent untabulated reservoirs in the study area are divided into two types.Type I with the permeability higher than 40×10^-3?m²and type II independent untabulated surface reservoir with permeability not higher than 40×10^-3?m².The remaining oil in independent untabulated reservoirs has the characteristics of small area and scattered distribution,and its production situation is generally poor.