Imaging a Fault Zone as a Potential Pathway for Radioactive Waste Migration using Semi-Airborne Electromagnetic Methods

Summary The safe long-term management of high-level radioactive waste is a major global challenge. Airborne geophysical methods were developed for mineral and petroleum exploration. They also recently applied to study environmental risks where large areas must be characterized. In 2024, a helicopter-based semi-airborne electromagnetic (SAEM) survey carried out at Saxony, Germany, to conduct research on a radioactive waste repository close to a faut zone where the radioactive waste could escape. We aim to image a conductive fault system whose electrical conductivity is connected to hydrothermal activities, which leads to mineralization inside or in the vicinity of the fault. For this purpose, we installed two individually grounded bipole transmitters in the study region. Since EM methods are sensitive to conductive material, SAEM methods have the capability to image this fault. Although man-made infrastructure in the study area introduces signal interference that distorts responses from subsurface anomalies, the inversion results confirm the feasibility of SAEM for imaging the conductive fault zone.