Azimuthal anisotropy in the lithosphere from observations of long-period S-waves

Abstract

The paper gives a detailed description of the technique for measuring azimuthal anisotropy which was suggested earlier by Vinnik, Kosarev & Makeyeva (1984) and used by Kind et al. (1985). The technique is based on the observations of long-period converted phases like SKS. Additionally, we describe a generalization of this approach which makes use of long-period S-waves of arbitrary polarization. Both modifications were applied to records of the GRF array in southern Germany. The results of this analysis, if combined with the data on Pn velocities (Bamford 1977), suggest that the direction of the fast velocity in the lithosphere of the region varies with depth.