Spectral Analysis of Surface Waves
Description of the Method
Searches can be done using surface arrays, cross-borehole techniques or a combination of surface and borehole (Vertical Seismic Profiling). Vertical seismic profiling (VSP) is a seismic technique that measures acoustic waves between a well bore and the surface. It differs from surface seismic by being both higher resolution and by giving the geoscientist the ability to analyze the wave fields in situ. Additionally, due to its high resolution, VSP can image objects within the vicinity of the borehole that could not otherwise be defined by surface techniques. Surface arrays are the least intrusive seismic method and are capable of identifying meter-dimension targets at depths of 10s of meters if the local geology is not too complex.