HR: 1340h
AN: S43B-1070    [Abstracts]
TI: Improvement of the SCEC-3D Model of the Los Angeles Basin Using Teleseismic Receiver Functions
AU: * Chu, R
EM: chur@slu.edu
AF: Saint Louis University, 3507 Laclede Ave., Saint Louis, MO 63103 United States
AU: ZHU, L
EM: lupei@eas.slu.edu
AF: Saint Louis University, 3507 Laclede Ave., Saint Louis, MO 63103 United States
AB: A three-dimensional velocity model of the Los Angeles Basin has been developed by the Southern California Earthquake Center (SCEC) for simulating strong ground motion, site effects, and locating earthquakes. P-wave velocities in the model are derived from oil logs, stratigraphic surfaces, and seismic tomography. S-wave velocities and densities are determined by empirical rules. To verify and refine the SCEC model, we obtained 509 teleseismic receiver functions of five broadband stations in the LA basin. Receiver functions of all five stations show strong azimuthal variations related to basin geometry. We modeled those variations using the generalized ray theory and the finite-difference method. Preliminary results show that the SCEC-3D model is inadequate in predicting the observed receiver function waveforms. Certain modifications of basin thicknesses, Vp/Vs ratios, and the geometry of the bottom interface in the model need to be made.
DE: 7299 General or miscellaneous
SC: Seismology [S]
MN: Fall Meeting 2005