On viscosity and the inelastic nature of waves in geological media

abstract An asymptotic solution for spherical wave propagation in linear viscoelastic solids is compared with particle velocity measurements from underground explosive tests in tuff; the magnitudes of these experimental data are of the order of 5 ×102 cm/sec. The qualitative nature of the theoretical solution is similar to that of the measured velocity time histories. When material and kinematic parameters in the model are specified, good quantitative agreement is obtained with respect to radial attenuation of the magnitudes and radial growth of the wavelengths. Both the phenomenological character of the viscoelastic model and limitations on its applicability are discussed.