A FIELD INVESTIGATION OF SOURCE PARAMETERS FOR THE SLEDGEHAMMER

We examined amplitude and frequency changes in shallow seismic-reflection data associated with simple source-parameter modifications for the sledgehammer. Seismic data acquired at three sites with different near-surface geology show the potential effects of varying the hammer mass, the hammer velocity, the plate mass, and the plate area. At these study sites, seismic amplitudes depend on plate-surface area and on hammer mass but not heavily on hammer velocity or plate mass. Furthermore, although the total bandwidth of the recorded data was independent of source parameter changes, the peak frequency at one site was increased approximately 40 Hz by increasing the area of the plate. The results indicate that the effects of modifying the source parameters for the sledgehammer are site-dependent. The experiments described are quick, cheap, and simple, and can be duplicated by others at prospective sites to answer site-specific questions.