How does GPR work?
Ground penetrating radar uses electromagnetic wave propagation and scattering to image, locate and quantitatively identify changes in electrical and magnetic properties in the ground or concrete. It may be performed from the surface of the earth, in a borehole or between boreholes, from aircraft or satellites. It has the highest resolution in subsurface imaging of any geophysical method, approaching centimeters under the right conditions. Depth of Investigation varies from the surface to over 5,400 meters, depending upon material properties. Detect ability of a subsurface feature depends upon contrast in electrical and magnetic properties, and the geometric relationship with the antenna. Quantitative interpretation through modeling can derive from ground penetrating radar data such information as depth, orientation, size and shape of buried objects, density and water content of soils, and much more. GRORADAR? By Gary R. Olhoeft, PhD