Effect of Two Different Protective Surface Materials on Ground Penetrating Radar Signal Characteristics

Minimizing the disturbance caused during ground penetrating radar (GPR) data collection at archaeologic sites with loose surface material, such as at the Wonderwerk Cave, is critically important to archaeologists. We evaluate the potential use of two commercially available materials that could protect the surface from the movement of the GPR antennas. The average time amplitude and average frequency spectrum from GPR data collected on each material indicate differences between the materials, in addition to the difference to GPR data collected directly on the ground surface. Further differences are documented for the velocity estimates from a subsurface reflection. However, the amplitude versus offset from the same reflection is similar between the GPR data collected on the different surface protective materials and the direct contact data.