Quantitative Identification Method of Injection Production Dominant Channel in a Marine Sandstone Reservoir

Good sweep improvement in waterflooding reservoirs requires an understanding of the dominant channel between injector and producer during tertiary recovery process. In this context, marine reservoirs present unique challenges. The insulating layer of a marine sandstone reservoir is very poor, which leads to interlayer channeling and fast water-cut rising. The complex relation between oil movement and water movement contributes to profile modification challenges. In this study, a quantitative method using an ensemble of static data such as logging interpretation data, characterization data of sedimentary lithofacies and interbeds between wells, and dynamic data like production data, perforation data, waterflooded layer interpretation data, and testing data was first established to understand the predominant connection relationship between injector and producer. The proposed method was used to identify the injection production dominant channels of seven well groups in a marine sandstone reservoir. The results showed that the channel development mode can be classified into two types of development in the same layer and development across the layer, and the ratios were 53.57 and 46.43%, respectively. The development depth of injection production dominant channel could be identified to 1–2 m inside layer. The identification results could provide a practical guidance during profile modification in the tertiary recovery process.