GEOMETRY OF THE GARLOCK FAULT ZONE BASED ON SEISMIC-REFLECTION DATA

Detailed examination of shot gathers from line 3 of the Consortium for Continental Reflection Profiling Mojave experiment indicates a low-velocity, high-amplitude seismic event that may originate from a south dipping portion of the Garlock fault zone. Part of this event was previously interpreted as a subhorizontal surface located in the midcrust. Our analysis indicates, however, that the distance to this event varies consistently with the distance of the shot and receivers from the fault zone and that the velocities are too low for seismic waves traveling through predominantly crystalline rocks. These characteristics are more consistent with the presence of a subvertical reflector located near the Garlock fault zone than with the previously inferred subhorizontal reflector beneath the seismic line.