GPR has limitations
where it can be used. It is like other geophysical instruments. A map from the US Dept. of Agriculture NRCS suggests some of the best areas for ground penetrating radar to be use. Other more detailed state maps are available from NRCS showing where ground penetrating radar is suitable.
Where Does Ground Penetrating Radar Work?
Tell us about your GPR experience by posting a response at the bottom of the page.
Areas shaded purple are labeled unsuited and areas shaded dark green are very high on the index, suggesting good record areas. Off white is listed as moderate.
Good ground penetrating radar results
are often spectacular.
Ground penetrating radar results from a bad record area are of little or no value. With a known target at a site to test the ground penetrating radar unit’s response, it is easier to predict if ground penetrating radar is a good choice. Geophysicists, engineers, geologists, military, and underground utility locators need to consider the soil conditions and select antennas accordingly. There are many case histories where ground penetrating radar has succeeded because of good subsurface conditions. Electrically resistive materials (e.g., dry sand and gravel or solid rock) improve the depth of penetration of ground penetrating radar. Typically scattering or absorption of the electromagnetic pulse reduces the quality and strength of the returned GPR signal. While all frequencies can experience scattering, the GPR signal from higher frequency antennas are more often absorbed. The media the GPR signal needs to pass through often dominates the success of a GPR survey. Good soil conditions are necessary for good results. ground penetrating radar instrumentation often plays a much lessor role. If you can not get the ground penetrating radar signal to penetrate the soil to the target of interest and then reflect back to the receiver, you, the client, the engineers, the geologists, and many others will not be happy with the ground penetrating radar results.