Immiscible two fluids that consist of wetting and nonwetting fluids against minerals are valuable for understanding the subsurface porous reservoirs. The presentation was related to the following topics:
1. The relationship between the P- and S-wave velocity ratio and transport properties of the reservoir sandstones.
2. The behavior and physical mechanisms of the immiscible two-fluid flow in the porous sandstones.
3. The basic framework of Biot’s poroelasticity theory and the essence of the second P-wave.
