The inhomogeneity angle (the angle between the real and imaginary parts of the wave
vector) is seldom taken into account in estimating attenuation coefficients from seismic data.
Wave propagation through the subsurface, however, can result in relatively large
inhomogeneity angles ξ, especially for models with significant attenuation contrasts across
layer boundaries. Here we study the influence of the angle ξ on phase and group
attenuation in arbitrarily anisotropic media using the first-order perturbation theory verified …