This project follows two the preceding two projects, DESMEX and DESMEX II. In the first phase, a new semi-airborne (i.e. transmitter on the ground and receiver in the air) exploration methodology for ore deposits was developed (Becken et al. 2020) and tested on demonstration cases in Schleiz, Germany, and Kiruna, Sweden (Steuer et al. 2020; Smirnova et al. 2020). The second phase focused on the application of the method to several deposits in Germany, Namibia (Becken et al. 2023) and Spain in rather local scales. Additionally to helicopters, drones have been used as alternatives to helicopters. Morover, alternative methods like AFMAG (audio-frequency magnetotellurics) have been added (Stolz et al. 2022). The third phase of the project, DESMEX real, is a so-called real laboratory with the aim of investigating deposits in the district scale, by using the former mining are of the upper Harz mountains.

Apart from the joint measuring campaigns, the focus of the work at LIAG is on the software development. While in DESMEX the finite-element modelling package custEM was created (Rochlitz et al. 2019), it was extended to inversion (Rochlitz et al. 2023) in DESMEX II in order to be able to generate three-dimensional conductivity models based on the measured data. With that, an extended synthetic study was done to optimize survey design (Nazari et al. 2023). In DESMEX-real, the inversion algorithms are further developed towards large-scale inversion of extended areas of different resolution using hierarchical approaches aiming at geological models for the Harz mining region.

Additional to mineral deposits, groundwater questions are coming into the focus to demonstrate the transferability of the methods into other fields of interest.