Helmholtz Centre Potsdam
GFZ German Research Centre for Geosciences
Abstract (EDOC: 1064)
Estimates of the parameters of shear-wave splitting in the records of SKS and SKKS of the new German Regional Seismograph Network (GRSN) for one-layer model show large azimuthal variations at some stations of the network. It is found that the variations are compatible with the presence of two anisotropic mantle layers in the region of the South German Triangle (SGT); the fast direction in the upper layer is between N-S and NE-SW, close to the previously reported estimates of the fast direction in the subcrustal lithosphere of the SGT. The fast direction in the lower, presumably asthenospheric layer is close to E-W. The estimates of the effective fast direction for one-layer model at the stations of the GRSN confirm the previously noted tendency of the fast direction of mantle anisotropy in Central Europe to change from 50° - 70 ° in the western part of the region to 100° - 120°! in the eastern part. A correlation of this change with a bending of the present-day direction of maximum horizontal stress in the crust suggests that anisotropy in the asthenosphere of Central Europe can be related to the Alpine orogeny.
(1994): Shear wave splitting in the records of German Regional Seismic Network.. Geophysical Research Letters, 21, 6, 457-460.