Geological Characteristics and Waterflooding Strategy for Yuanshi Low Permeability Sandstone Reservoir

Core test data from 10 wells indicate that the sandstone reservoir in Yuanshi oilfield is characterized by low permeability, thin pore throat, high clay mineral content, and strong sensitivity, which are likely to cause reservoir damage and affect development result. Based on the characteristics of water-sensitive, velocity-sensitive low permeability reservoir as well as non-Darcy flow behavior, the development strategy of high pressure water injection and cyclic water injection has been formulated with the assistance of engineering measures such as fracturing and reducing well spacing.