Multi-regional sinkhole susceptibility mapping in the Federal Republic of Germany

The Federal Company for Radioactive Waste Disposal (BGE) commissioned us to assess sinkhole susceptibility (1:250 000 scale) in areas relevant to the search for a final nuclear waste repository. In these areas favorable geological conditions for the safe final disposal of high-level radioactive waste can be expected. Each German geological survey contributes to geohazard mitigation within its respective federal states, addressing hazards such as sinkholes. To support this effort they document karst features in regional inventories. Our proposed work will be underpinned by these homogenized state inventories supplemented by data from selected publications with a connection to the geological surveys. Key parameters will be the general geological map of the Federal Republic of Germany (GUEK250), and the geological map of the Federal Republic of Germany (GK1000). These maps are supplemented with information from the borehole map of Germany and the geological 3D model of the deep subsurface in the North German basin (TUNB).
We differentiate between carbonate, sulphate and chloride karst. Each entry in the harmonized inventory is assigned a classification based on its karst type. Using geological maps, borehole information and TUNB we plan to derive binary maps showing the availability of soluble rocks for each karst type. These maps in combination with the karst type specific inventory allow us to delineate karst prone areas in Germany susceptible to sinkhole formation. Regional datasets will be used for validation through comparative analysis. To take into account regional variability we want to engage with local geological professionals from across Germany.