Comparison of surface vs. cross-hole seismic methods for void detection in the shallow sub-surface

Detecting near surface voids is a major challenge in the field of near surface geophysics which encompasses many different techniques: electrical methods, gravity, ground penetrating radar (GPR) as well as seismic methods. While multiple methods have been previously examined, as yet none of them provide a reliable tool that would successfully detect voids in diverse geological setting and at variable depths. We examine two near-surface seismic survey configurations for locating and imaging near-surface voids. The first being surface seismic configuration where sources and receivers are deployed solely on the surface; the second, cross hole configuration using receivers and sources from neighboring boreholes located at both sides adjacent to voids.