Ground Water Survey with a New Capacitance Probe

Abstract

Original in-situ HF technique of material dielectric characterization in the 1-20 MHz have been developed and validated in order to estimate the moisture content of soils. The 1-20 MHz device is based on 2 electrodes put into the soil and separated from a distance of up to 30 cm. As the probe system is able to investigate several layers constituting a stacking of electrodes, a moisture profile of the soil can be obtained. The system is based on the determination of the complex impedance (ratio voltage/current through the soil impedance) in a variable frequency from 1 to 20 MHz. The measurement requires a calibration on several soil types to reach acceptable accuracy for water content. The design and data processing as well as preliminary results obtained from laboratory experiments are presented.