Shear-wave splitting of Sichuan Regional Seismic Network

Using seismic data recorded by the Chengdu Digital Seismic Network from May 1, 2000 to December 31, 2006, we obtain the dominant polarization directions of fast shear-waves at eight digital seismic stations adopting the SAM technique. The results show that the dominant directions of polarizations of fast shear-waves at most of stations are mainly in nearly NE-SW or NW-SE direction in Sichuan. The dominant polarization directions of the fast shear-waves at stations located at the active faults or intersection of several active faults are consistent with the strikes of active faults which control the earthquakes used in the analysis, and are basically consistent with the directions of regional compression axis. However, several stations show that the fast shear-waves are not consistent with the strikes of active faults and the directions of regional compression axis, due to the influence of local complicated crustal structure.