The dielectric characteristics of many dielectrics deviate from the debye theory, which assumes the existence of one single relaxation time and ignores the conductive loss. These results are in agreement with experimental observations. ] shows a qualitative agreement with the measured data of the current study. The higher the reflection coefficient, the higher the possibility for the detection of the contaminant [. Estimation of penetration depth from soil effective temperature in microwave radiometry.
The detection of oil contamination in soils, by mean of the gpr, depends on the contrast of reflection coefficient between the dielectric permittivities of the clean and contaminated soil [. This phenomenon has a significant effect in determining the permittivity of the material. This is attributed to the fact that diesel oil replaces air contained within the pore spaces of the soil samples and changes the path of electric current conduction.