Methodologies and Observations of Shear-Wave Splitting for Seismic Anisotropy Analysis in Sorthern Caspian

This study analyzes seismic anisotropy in northern Iran using local earthquake data recorded by stations of the Institute of Geophysics, University of Tehran, and the International Institute of Earthquake Engineering and Seismology, from January ۲۰۱۸ to January ۲۰۲۰. Events with magnitudes greater than ۳.۵ were selected. Shear-wave splitting parameters, including pand St, were estimated using automatically selected analysis windows, and shear-wave velocities beneath each station were obtained through inversion modeling. Temporary stations were also used to improve data coverage. The results show a noticeable increase in velocity from the Caspian Sea margin toward the Alborz Mountains, and some differences from previous studies, likely due to local sedimentary conditions, recent large earthquakes, and the inclusion of additional stations.

کلیدواژه ها:

Body waves ، Local earthquakes ، Caspian Sea ، Anisotropy parameters