Lianxing Wen -> Research -> Seismology -> Los Angeles Basin


Map of southern California, displaying major faults, Los Angeles basin with seismic stations, two aftershocks, and the Landers fault rupture. The dashed light contours indicate the isosurface of the Los Angeles basin (from Yerkes, et al., 1965). OBG and DOW were triggered by the mainshock of 1992 Lander's Earthquake.

The best-fitting model and associated ray paths are shown at the top of the figure followed by two collumns of synthetics. Aftershock synthetics (left) start with a prediction at PAS (Pasadena, hard rock site). Peak amplitudes in cm are given above each trace. Simulations of the mainshock are given on the right starting with the observation at Pasadena. The synthetic at PAS for event 940801 fits the observation very well for this one-dimensional model.

The basin responses at OBG and DOW due to the different types of incident energy. The top traces are the observed displacements. The basin responses due to incident sSmS (reflected from surface and turned back to surface by the Moho discontinuity), SmS (downdoing and turned back by the Moho), sS8.5S (reflected from surface and turned back by an interface at 8.5 km depth) and direct upgoing wave are labeled as sSmS, SmS, sS8.5S and Upgoing. Those responses are generated by convolving the transfer functions related to each incident group of rays with moment rate function, obtained by deconvolving the PAS aftershock from mainshock.