The plane wave propagation in an inhomogeneous anisotropic thermally conducting elastic solid is studied with two thermal relaxation times. Three types of plane waves—quasi-P, quasi-S, and thermal waves—are shown to exist. The analytical expressions for their velocities of propagation are obtained. The inhomogeneity drastically affects the velocity of these waves and also depends on the angle of propagation and frequency. The effects of these parameters are shown graphically.

Dispersion of Rayleigh-type surface waves is studied in a sandy layer under a uniform layer of homogeneous liquid lying over liquid-saturated porous solid half-space. The frequency equation in the form of a ninth-order determinant is obtained and evaluated. Special cases have been deduced and dispersion curves for the phase velocity and wave number have been plotted for a particular model.

The present study deals with reflection and transmission of plane waves between two different fluid-saturated porous half-spaces, where longitudinal and transversal waves impinge obliquely onto the interface. Amplitude ratios of various reflected and transmitted waves are obtained. Variations of amplitude ratios with the angle of incidence are depicted graphically. A particular case of reflection at the free surface of the fluid-saturated porous half-spaces is discussed.