The effect of boundaries on wave propagation in a liquid-filled porous solid: IV. Surface waves in a half-space

Abstract

Dispersion and dissipation of Rayleigh-type surface waves in a porous, elastic half-space filled with a viscous liquid are studied within the framework of Biot's field equations. The algebraic secular equation turns out to be of the seventh degree, its (complex) coefficients being functions of a dimensionless frequency parameter. It is shown that for small and for large values of this parameter the wave is essentially non-dissipative. A numerical analysis of the secular equation pertaining to a kerosene-saturated sandstone reveals the existence of several extremal values of the phase velocity, a skewed bell-shaped variation of the dissipation per cycle, and a high-frequency cutoff for the surface wave for certain values of the dynamical coefficients.