Imaging subsurface structures using electromagnetic induction measurements

Electromagnetic Induction (EMI) is a geophysical method that measures the soil apparent electrical conductivity (ECa) which is then related to various soil characteristics such as water content and texture. Compared to direct current methodologies, the advantage of the EMI technique lies in its mobility, allowing high resolution measurements of various hectares per day. The drawback of this technique is that multiple factors affect EMI measurements, and that these factors are variable in time and space.

In this joint project within the TR32 project (Transregional Collaborative Research Center TR32), we aim to break the boundary between field scale and large scale EMI studies. We focus on the characterization of a 1 by 1 km area using multi-configuration EMI that allows for the collection of ECa values at different depth of investigation (DOI). Generalization methodologies assisted by direct soil sampling are implemented and tested to obtain high resolution maps of homogeneous subsurface structures in terms of layering and texture. The final aim is to produce large-scale high-resolution soil maps than can prove essential for hydrological modelling applications, precision agriculture, and environmental studies.