Summary
A method of relative location using surface waves is developed and tested. It requires a reference event whose signals are cross-correlated with those of another event in the same source area to obtain relative travel times to a given network. The location is computed relative to the reference event with an algorithm similar to body-wave location, except the depth variable is deleted.
The BOXCAR explosion at the Nevada Test Site was located with surface waves using both a distant (FAULTLESS) and a nearby (JORUM) reference event. In both cases the error from the true location was approximately 10km. P-wave location of this same event after applying travel-time residuals from FAULTLESS was in greater error (23 km) and after applying JORUM residuals was in less error (6 km).
The surface-wave location method helped to identify the BENHAM collapse and also provided some information on the mechanism of collapse. The method was also applied to one earthquake to demonstrate the discrimination potential of differences in initial-phase patterns between explosions and earthquakes.
