A Simple Calculation Method for Water Oil Contact in Heterogeneous Reservoir: A Case Study of Nanpu 1–1 Block in Jidong Oilfield

The oil-water interface in a single reservoir is a fluctuating surface, and accurate calculation of the depth of the oil-water interface is of great significance for finely developing the reservoir. Based on the existing methods for determining oil-water interfaces, multiple methods are used in combination to determine the oil-water contact. Wells where the oil-water contact has already been determined in the reservoir are selected as reference wells. Based on the stress balance equation, expression for the relative depth of the oil-water contact is established between the computed well and the reference well. Using the relationship between capillary pressure and reservoir properties, the calculated parameters are converted into commonly used logging interpreted porosity and permeability in oil field development. This method requires fewer calculated parameters, and practical applications have proven the high calculation accuracy of the method, which is a convenient method for calculating the depth of the oil-water contact in heterogeneous reservoirs.