Joint inversion of airborne TEM data and surface geoelectrical data. The Egebjerg case

In modern hydrogeological investigations with dense data coverage, the aim is to combine several different sources of information about subsurface structures to enable the best possible geological and hydrogeological interpretations from which a dynamic hydraulic model can be constructed. In this paper, the Egebjerg area in Denmark is used as an example of the process of combining airborne transient electromagnetic data with groundbased galvanic geoelectrical data in a joint inversion to produce a better resolution of the subsurface resistivity structure than would be possible using each of the methods alone. The joint inversion is realised by mutually constraining the inversion models of one data set with the inversion models of the other, overcoming the differences in scale and resolution power that are inherent in this type of effort.