Analysis of reservoir physical properties and influencing factors of high water cut sandstone reservoir in Gaoyou sag

After long-term water injection, the physical properties of high water cut sandstone reservoirs will change, which will have an obvious impact on reservoir development. Therefore, by using different cores with different permeability, water erosion experiments were carried out. Based on the experiment results, the effects of clay minerals, pore throat characteristics and rock wettability on reservoir physical properties were analyzed. The experimental results show that the permeability of the sample with high permeability increases with the increased number of injection multiple, and the permeability of the sample with low permeability decreases with the increased number of injection multiple. And different injection rate will affect the final change degree of physical properties. Clay mineral content, pore throat characteristics and rock wettability have influences on reservoir physical properties, among which clay mineral content has the greatest influence on physical properties, while pore throat characteristics and rock wettability have less influence.