Observation of volumetric water content and reflector depth with multichannel ground-penetrating radar in an artificial sand volume

The performance of the multichannel ground-penetrating radar (GPR) method introduced by to simultaneously estimate reflector depth and average volumetric soil water content is tested on an artificial soil volume. The test site consists of several layers of sand which are partly water saturated. Volumetric water content and reflector depth deduced from the GPR measurements are compared with in situ measurements. It is shown that both reflector depth and volumetric water content can be reconstructed with an accuracy of about 0.1 m and 0.03 ... 0.04, respectively. Possibilities for improving the multichannel GPR method are identified in terms of the employed ray path model and the measurement setup.