Block Model for Growth of Steam-Heated Zone in Oil-Bearing Naturally Fractured Carbonate Reservoirs

A model for steam injection into naturally fractured carbonate reservoirs provides a method of calculating the volume of heated formation for a given amount of steam, provided that the assumptions of the model are satisfied. The model represents the fractured reservoir by a system of blocks, dependent on fracture spacing and dimensions. The amount of oil mobilized can be estimated from prior measurements of oil saturation and laboratory tests of oil-displacement efficiency. Results comparable to observations are obtained. In addition, the temperature distribution along the direction of propagation in the reservoir may also be estimated, providing a guide to variation in the local oil mobility. These results can assist in evaluating the effectiveness of steam injection in the recovery of oil from naturally fractured formations.