Remaining Oil Distribution Regularity Of Multilayer Edge Water Reservoir In L Oil Field

At present,most of the reservoirs in China are in the stage of high water cut,facing such problems as the remaining oil is dispersed,and the remaining oil is hard to tap,However,the remaining oil recoverable reserves are still considerable,the study of the remaining oil distribution law,to enhance oil recovery is the primary theme.L reservoir is a stratiform edge water reservoir,which is divided into two layers L1 and L2.The contradiction between the two layers is prominent,resulting in large differences in the degree of utilization and the remaining oil is dispersed.In this paper,according to the development status and geological characteristics of L reservoir,the remaining oil is quantitatively described by reservoir engineering method and numerical simulation method,and the remaining oil-rich area.According to the core wash level table and the displacement efficiency formula,the oil saturation of the remaining oil saturation area corresponding to the rich area,the weakly enriched area,the flooded area and the strong flooded area is obtained.When the water cut is 90%,the remaining oil area of each area is calculated by the octuple principle,and the proportion of remaining oil area in each area is calculated as the quantitative indicator,The distribution law of remaining oil in plane and its influencing factors were analyzed.The conceptual model was established using the L field as a prototype and the residual oil saturation calculated at 20% flooding efficiency was taken as the boundary of remaining oil enrichment,When the water cut is 90%,the dimensionless well spacing between oil and water wells is abscissa and the thickness of remaining oil-rich area accounts for reservoir thickness ratio as ordinate,which is used as quantitative indicator,Analysis of the remaining oil distribution patterns and influencing factors,Based on this,a two-layer model was established to analyze the distribution of remaining oil between layers and the influencing factors.Based on the history fitting of L oilfield,the research results applied to the actual block,oilfield production has practical significance.