9316871 Henyey This research is to reduce and analyze seismic reflection data from the Mojave Desert and San Bernardino Mountains in Southern California. The seismic data were collected using three-channel portable recorders to detect seismic waves generated by aftershocks of the 1992 M=7.5 Landers earthquake. The goal of the experiment is to study the depth of the crust in the region by comparing the travel time differences between waves traveling through the crust and those reflected from the base of the crust. Crustal depths are important to models of the shape of the San Andreas fault surface in the southern California region. This research is a component of the National Earthquake Hazard Reduction Program. ***