Streamline-Based History Matching Constrained to Reservoir Geostatistics Using Gradual Deformation Technique

Abstract

A new and general procedure for history matching that uses streamline simulation and a gradual deformation technique has been proposed. Streamline trajectories define the major flow paths and help the algorithm to modify the reservoir model only in the regions that cause the mismatch between simulation results and field observations. The use of a gradual deformation technique enables the algorithm to remain constrained to reservoir geostatistics. It also reduces the number of independent variables in the optimization problem. In our algorithm, effective conductivities are defined along each streamline. The effective streamline conductivities are then adjusted using the values of measured and computed breakthrough times of individual streamlines. Then an intermediate objective function is defined to minimize the difference between adjusted (desired) and computed effective streamline conductivities. The algorithm continues until a satisfactory match is obtained. In order to examine the quality of our history matching procedure, it is applied to a synthetic reservoir.