Computation method for water influx in different layers of natural edge water

To scientifically and objectively evaluate the development effectiveness and separated layer production of favorable natural water edge reservoir and to improve the computation method for volumes of water influx in different layers, this study applies a novel technique to simulate the process of natural water invasion by utilizing various geological and single wells’ data and deploying virtual injection wells at the oil-water interface of arbitrary shape. The denser the virtual injection wells are deployed, the more precise the water invasion process can be. This study calculates water influx direction and intrusion resistance of natural edge water by discriminating connection relationship of separated layer between the virtual injection wells and production wells. Referring to hydropower similarity principle, it calculates intrusion resistance of each layer and total invasion resistance of the reservoir, thus deriving the volume of water influx of each layer. The new method has been implemented in software and applied to over ten blocks in Dagang Oilfield, Liaohe Oilfield, Jidong Oilfield, etc. The results have shown that the method is more accurate for splitting production data to calculate separated layer water influx volume in each unit in natural water edge reservoir.