The thermal signatures of surface and buried land mines vary widely with time of day, weather, soil type, soil moisture content, and mine burial depth. There have been recent advances in modeling these effects, but until these models are fully developed and validated we will continue to rely on measured data. This paper witll present signatures in the medium-and long-wavelength infrared (MWIR and LWIR) spectral bands for surface and buried M19, M15 and VS1.6 anti-tank mines at two locations, a temperate site and an arid site. We will show that the apparent contrast of these landmines is substantial throughout the diurnal cycle except during thermal crossover periods after sunrise and sunset. Our results show that the mine signatures are well above sensor noise and that further improvements in sensitivity or resolution are not required. The paper will also present LWIR images of landmines buried in dirt and gravel road environments taken on a cold winter day and discuss the intriguing and unexpected differences observed between the images of landmines buried in dirt and gravel.
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