Metal detectors are the most common technique used to search for landmines, many of which reside in the tropics where intensively weathered soils have properties that can limit the performance of metal detectors. To examine the problem, geoscientists at the Leibniz Institute for Applied Geosciences and the Federal Institute for Geosciences and Natural Resources in Hannover, Germany analyzed the magnetic susceptibility of more than 500 soil samples from the entire tropical belt.
The study found that more than one-third of the measured soil samples may generate severe limitations when using metal detectors. While on average the susceptibility of soils with basaltic origin was higher than those of other origin, the variability within the different groups is high. This provides evidence that additional influences on soil susceptibility, such as soil development, likely exist.
The scientists hope to clarify whether residual enrichment of magnetic minerals is the dominant processes for increasing soil susceptibility during soil development. They hope to gain insight on whether it is more reasonable to use a soil map, a geological map, or both, to predict soil susceptibility. Such knowledge will allow detectors to be adapted to meet local conditions.