Identification of Dominant Seepage Channels in Water-flooded Reservoirs and Analysis of Their Effects
The existence and distribution of dominant seepage channels in reservoirs significantly affect reservoir development countermeasures and development effects.This paper uses multiphase seepage and reservoir geolo-gy theory to establish a method to characterize the connectivity of sub-layers between injection and production wells and identify the existence of dominant seepage channels.Based on the sub-layer comparison method,geo-logical modeling method and tracer method,the sand body connectivity and the development characteristics of dominant seepage channels of a representative well group in an oil field are dissected in detail.The research re-sults show that among the injection-production wells in the example well group in the study area,the reservoir connectivity rates obtained by the three methods are quite different.Among them,the connectivity rate deter-mined by the tracer method with higher accuracy is 40％,and three dominant seepage channels are identified in the key anatomical layers.The development degrees of the three dominant seepage channels are graded accord-ing to the tracer seepage rate and recovery rate.Compared with the actual monitoring results,the connectivity rate obtained by the comparative analysis of the sub-layer is obviously high,and the connectivity rate obtained by the geological modeling method and the tracer method is relatively close,and the connectivity rate obtained by the two methods is affected by the reservoir sedimentation and facies transformation law,heterogeneity and the fineness of the measured data of the developed sub-layer.The tracer method has the best effect in identifying the dominant seepage channel,and the identification accuracy is 25％higher than that of the geological model-ing method.
万方数据
维普
