GPR case histories and known physical principles

The physics and technology of ground penetrating radar [GPR] and its ability to detect buried targets are well understood and proven even though the underlying physics and engineering are not simple. Its performance can be predicted with some accuracy given information on the characteristics of the soil and target. Where new developments in GPR can demonstrate proven outcomes within a framework of statistically based evidence and procedures, as well as known science and engineering methodology, then prospective end users can be confident in their use. However, some performance claims that need very careful scrutiny are proposed by certain operators. These claims are usually quickly discounted by the well informed, but appear plausible to the less knowledgeable and it is the aim of this paper to help end-users ask the right questions. The promise of “new” scientific breakthroughs, even where these remain unproven using the normal scientific procedures and in some cases transcend known physics, can mislead those unfamiliar with the proven science and technology underlying GPR. This paper very briefly reviews the fundamental physics of ground penetrating radar and methods of establishing whether or not it will accomplish a given goal. Several examples of claims regarding ground penetrating radar are described as well as the criteria against which new techniques are normally assessed. The paper concludes with a simple check list that could be applied by those about to consider the acquisition or use of ground penetrating services or equipment.