About The Project
The DESMEX joint project and the follow-up project DESMEX II have been funded since 2015 as part of the BMBF (now BMFTR) program r4 – Innovative Technologies for Resource Efficiency, Research on the Provision of Economically Strategic Raw Materials in the field of “Extraction of Primary Raw Materials – Development of Concepts for the Exploration of Primary Raw Materials.”
With the DESMEX-REAL joint project, a real-world laboratory for raw material exploration was established in 2021 in the former mining region of Oberharz as part of the BMBF framework program Research for Sustainable Development (FONA3). In the next stage (DESMEX-MinD, 2026-2029), exploration is to be extended to several locations in the Ore Mountains and the conductivity models obtained are to be converted into geological and deposit models.
The main objective of the DESMEX projects is to develop ground-airborne electromagnetic (EM) methods for exploring deposits at depths of up to 1 km. The focus in DESMEX was on implementing the semi-airborne EM method. For this purpose, high-voltage power sources are installed on the ground and the induced magnetic fields are measured during a flight. In DESMEX II, the results are to be transferred to purely passive measurements based on the AFMAG principle and to drone-based measurement systems. Demonstration measurements and the development of workflows for data analysis and inversion are essential components of DESMEX II and important steps towards the exploitation of the developed methods. Other aspects of DESMEX II include airborne mapping of gravity anomalies and the use of technical infrastructure as signal sources. The real-world laboratory tested new exploration technologies on an industry-relevant scale, taking regional geological, mining, and social conditions into account.
The main objectives at TU Bergakademie Freiberg, in collaboration with the LIAG Institute for Applied Geophysics, are the methodological developments of the evaluation procedures (3D inversion), see the network page and project pages DESMEX I, DESMEX II, and DESMEX-REAL.
Publications
- Rochlitz, R., Günther, T., Kotowski, P.O. & Becken, M. (2025): Semi-airborne electromagnetic exploration of deep sulfide deposits with UAV-towed magnetometers - Part 2: Inversion & Resolution analysis, Geophysics, doi:10.1190/geo2024-0448.1.
- Kotowski, P. O., Becken, M., Rochlitz, R., Schmalzl, J., Ueding, S., Tolksdorf, P., Wilhelm, A., & Symons, G. (2025). Semi-airborne electromagnetic exploration of deep sulfide deposits with UAV-towed magnetometers — Part 1: Processing and modeling. Geophysics, 90(3), WA261–WA274. doi:10.1190/geo2024-0453.1
- Mörbe, W., Yogeshwar, P., Tezkan, B., Kotowski, P., Thiede, A., Steuer, A., Rochlitz, R., Günther, T., Brauch, K. & Becken, M. (2024): Large-scale 3D inversion of semi-airborne electromagnetic data - topography and induced polarization effects in a graphite exploration scenario. Geophysics 89(5), B339-B352, doi:10.1190/geo2023-0471.1.
- Nazari, S., Walther, C., Thiede, A., Schiffler, M., Rochlitz, R., Becken, M., & Günther, T. (2024). Large-Scale Mineral Exploration using Semi-Airborne EM in Harz Mountains, Germany. NSG 2024 5th Conference on Geophysics for Mineral Exploration and Mining, 1–5. doi:10.3997/2214-4609.202420173
- Rochlitz, R., Becken, M. & Günther, T. (2023): Three-dimensional inversion of semi-airborne electromagnetic data with a second-order finite-element forward solver. Geophys. J. Int. 234(1), 528-545, doi:10.1093/gji/ggad056.
- Rochlitz, R., Seidel, M., & Börner, R.-U. (2021). Evaluation of three approaches for simulating 3-D time-domain electromagnetic data. Geophysical Journal International, 227(3), 1980–1995. doi:10.1093/gji/ggab302
- Rochlitz, R., Skibbe, N. & Günther, T. (2019): custEM: customizable finite element simulation of complex controlled-source electromagnetic models. Geophysics 84(2), F17-F33, doi:10.1190/geo2018-0208.1.
