Figure 1. LABPSE seismic stations are red (noncaustic) and yellow (caustic) diamonds. Events used in this study are displayed as focal mechanisms. Those events that had no focal mechanism available are located within clusters of events with focal mechanisms. Event numbering goes as increasing back azimuth from station 11. LAB, Los Angeles basin; SB, Seal Beach; SGB, San Gabriel Basin; SGM, San Gabriel Mountains; WF, Whittier Fault.