Measurements and modeling of soil water distribution around landmines in natural soil

Soil water content, dielectric constant, electrical conductivity, thermal conductivity and heat capacity affect the performance of many sensors (e.g. GPR, TIR) and therefore the detection of landmines. The most important of these is water content since it directly influences the other properties. We measure soil water distribution around an antitank and an antipersonnel mine buried in a sand soil under varying moisture levels. After a period of two days with 38 mm precipitation the water content below the AP-mine increased from 0.07 to 0.12 [m3/m3]. The water content above and below the AT-mine increased from 0.09 to 0.17 [m3/m3] and 0.09 to 0.13 [m3/m3], respectively. Below the AT-mine it was 0.02 to 0.04 [m3/m3] dryer than above the mine. The dielectric constant of the soil was estimated from the soil water content. After a dry period of two weeks the dielectric contrast between the AT-mine was approximately 2 [F/m]. After a period of 38 mm precipitation the contrast between AT-mine and background increased to 6 [F/m]. Differences in soil water distribution around the AT-mine caused a maximum dielectric contrast 4.5 [F/m] between background and mine. This effect was less apparent around the AP-mine (1.3 [F/m]). Differences in measured and simulated soil water distribution around an AT-mine urge for further investigation