Laboratory Tests and Field Surveys to Explore the Optimum Frequency for GPR Surveys in Detecting Qanats

Abstract In this paper, we discuss the results of laboratory tests and field surveys using ground penetrating radar (GPR) method to detect qanats at main campus Shahid Bahonar University Kerman (SBUK), Iran. The purpose experiments was explore optimum frequency GPR for subsoil in study site. We performed a variety with 3 GHz antenna (simulated dielectric empty targets) hosted by sand volumetric water content (VWC) values range 1.5–8%. depth each target progressively increased until either approaching edges sandbox or modelling qanat which data could not anymore. scaling factors were calculated test estimate maximum detecting as function scaled frequency. showed that areas where is dominated sand, medium-frequency antennas can penetrate depths few tens meters, but penetration considerably decreases when soil moisture and/or clay medium increase. Based on simulations, are detectable normalized about 15–17 times wavelengths very dry sands VWC less than 5% while rapidly drops down 4 more humid 8%. also measured 50 MHz 250 frequencies northwestern part area. processed images position compatible previous remote sensing studies detected 13.5 m, little bit beyond limit predicted tests.