On the effects of a dipping axis of symmetry on shear wave splitting measurements in a transversely isotropic medium

Abstract

We derive the explicit expressions for the phase velocities and polarizations of quasi-shear waves propagating in a transversely isotropic medium. The normal to the plane defined by the phase normal and the symmetry axis gives the exact polarization of S₁, while the polarization of S₂ also depends on the elastic parameters of the medium and is thus more complicated. Therefore, we propose that the polarization of the slow S₁wave, instead of the fast S₂ wave, as is common practice, should be determined from seismic data.