On the role of geothermal feedback mechanisms on tunnel valley genesis above salt domes ...

• Main Author: Bodenburg, Sascha Barbara
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: RWTH Aachen University 2023
• Subjects: Hochschulschrift; tunnel valley genesis; subglacial feedback mechanisms; Gorleben salt dome; southern North Sea; apparent heat capacity methods; heat conduction and hydrothermal flow; Ice Sheet
• Online Access: https://dx.doi.org/10.18154/rwth-2023-09361; https://publications.rwth-aachen.de/record/969814

Dissertation, RWTH Aachen University, 2023; Aachen : RWTH Aachen University 1 Online-Ressource : Illustrationen, Diagramme, Karten (2023). = Dissertation, RWTH Aachen University, 2023 ... : Physical feedback mechanisms between the subsurface and an overlying ice sheet are manifold. They lead to the development of special landforms, e.g. tunnel valleys. Tunnel valleys are widespread in (formerly) glaciated areas. They are eroded by subglacially flowing water. To investigate their genesis, it is necessary to model feedback mechanisms between the ice sheet and the subsurface. In the North German Basin, a possible spatial correlation between tunnel valleys and underlying salt domes was often observed. Partly, this was explained mechanically with the presence of faults. We want to investigate a different hypothesis for tunnel valley genesis based on the following geothermal argumentation: As salt better conducts heat than the surrounding rocks, the geothermal heat flux is augmented above. Hydrothermal groundwater flows through crestal faults enhance this effect. The resulting subglacial melting leads to subglacial rivers eroding the tunnel valleys. In order to determine the subglacial melting rate, ...