Comparison of pneumatic impact and magnetostrictive vibrator sources for near surface seismic imaging in geotechnical environments

For both test sites, the vibrator source proved to be more suitable to generate body waves than the impact source, which generates strong ground roll noise signals due to its non-controlled signal amplitude spectrum. In fact the control system of the vibrator source enabled improved adaption to varying ground conditions due to a controlled adjustment of the signal amplitude spectrum to optimize resolution and penetration for a given exploration depth.