Elastic Wave Velocity Versus Saturation and Pore Fluid Distribution Relationship

Continuous imbibition and dehydrating experiments were carried out with six kinds of sandstone in laboratory. Compressional wave velocity (VP) and shear wave velocity (VS), rate changes of imbibition and dehydrating with water saturation were measured during these two processes. The purpose is to analyze influence of pore fluid and pore fluid distribution on rock elastic properties at low saturation. The experiments show that the imbibition and dehydrating process have different velocity‐saturation relationships. Velocities are not only related to water saturation, but also related to pore fluid distribution during different saturation stages. The velocities are also associated with the physical and chemical interaction between water and rock skeleton.