Propagation of inhomogeneous plane waves in dissipative anisotropic poroelastic solids

A method is presented to decompose the complex slowness vector for the propagation of inhomogeneous plane harmonic waves in a general anisotropic medium. Phase velocity and attenuation coefficient are obtained along the arbitrary directions of propagation and attenuation, in 3-D space. The method is applied to study the propagation of inhomogeneous waves in an anisotropic poroelastic solid saturated with a viscous fluid. The variations of phase velocities and attenuation factors with the directions of propagation and attenuations are computed, for a realistic numerical model. Effects of these directions are discussed for low- and high-frequency propagation regimes of Biot's theory. The attenuations are found to be much more sensitive to the change in angle between the directions of propagation and attenuation, as compared to propagation velocities.