Fig 13-15; Kappa(T) measurements in the frame of a field study in Mozambique

Results and discussion Despite different degrees of weathering of the investigated soils, their magnetic mineral composition is dominated by lithogenic (Ti-) magnetites. Moreover, there are clues for the pedogenic neoformation of ultrafinegrained ferrimagnetic minerals in two of the three topsoils. The deterioration of metal detector performance at the sites results from the high frequency dependence of magnetic susceptibility at two locations and from the distinct spatial variability of topsoil magnetic susceptibility at all locations.

Conclusions To assess soil effects on the performance of modern metal detectors the investigations of frequencydependent susceptibility and of spatial susceptibility distribution are the most meaningful tools. Summarizing, the topsoil magnetic properties of the investigated sites are predominantly influenced by their parentmaterial and to a minor degree by pedogenic neoformation.