What is the frequency and amplitude of seismic testing?
The surface waves spread outwards cylindrically with typical dominant frequencies and velocities of 5-10Hz and 500-700m/sec. The subsurface compressional waves spread outwards spherically with typical dominant frequencies and velocities of 40-60Hz and 2000-3000m/s. Dominant frequencies are between 5 -10 Hz for surface waves and 40-60Hz for reflected waves. Maximum ground displacement is a fraction of a millimetre – approximately 0.1 millemetres from the source, and down to 4 or 5 magnitudes less at the extent of the detector spread from deep targets.
