Two decades of shear-wave splitting measurements in southern California

Zefeng Li, & Zhigang Peng

Submitted August 11, 2016, SCEC Contribution #6609, 2016 SCEC Annual Meeting Poster #191

We measure shear-wave splitting parameters (i.e. fast direction and delay time) of local earthquakes recorded by the Southern California Seismic Network from 1995 through 2014. A set of codes is used to automatically download three-component waveform data from the Southern California Earthquake Data Center (SCEDC), pick S-wave arrivals, and measure the splitting parameters without any human interference. We also calculate signal-to-noise ratio and measurement uncertainties and use them as quality control parameters. Initial check on some stations that were frequently studied (e.g. AZ.KNW) shows very good agreement between the new results and the previous ones using relatively short period of data. We are in process of cleaning up and compiling all the results. After that, we plan to analyze spatiotemporal variations of splitting parameters and compare them with regional stress measurements and community fault models to better understand physical mechanisms of crustal anisotropy in southern California. Updated results will be presented in the meeting.

Key Words
Anisotropy; Stress; Fault structures

Citation
Li, Z., & Peng, Z. (2016, 08). Two decades of shear-wave splitting measurements in southern California. Poster Presentation at 2016 SCEC Annual Meeting.


Related Projects & Working Groups
Seismology