Ground Penetrating Radar

Ground Penetrating Radar is a geophysical method that uses radar pulses to image the subsurface. This non conductive method uses electromagnetic radiation in the microwave band (UHF/VHF frequencies) of the radio spectrum, and detects the reflected signals from subsurface structures.   
 
GPR uses high-frequency radio  waves and emits electromagnetic  energy into the ground. When the  energy encounters a buried object  or a boundary between materials  having different Permittivity's, it  may be reflected or refracted back  to the surface. A receiving antenna  can then record the variations in  the return signal.

Ground Penetrating Radar