RELAX – Crustal relaxation below large impact craters inferred from novel imaging of analogue experiments

• Applicant: Professor Dr. Ulrich Peter Riller
• Subject Area: Palaeontology
• Term: from 2021 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 457039485

Hypervelocity impact is a fundamental geological process of the solar system. An outstanding problem in understanding large-scale impact cratering concerns the effect of viscous relaxation of crust below large impact craters on crustal flow and structural modification of crater floors. By implementing novel experimental techniques of imaging material flow in analogue experiments, the project promises to relate depth, diameter and morphology of model craters as well as thickness of model upper crust to crustal flow and patterns of crater floor fractures. By introducing high-frequency ground penetrating radar in combination with digital image correlation to visualize crustal flow, the capabilities of analogue modelling will be advanced significantly and will broaden the field of experimental tectonics. The study may close important knowledge gaps in planetary geology. For example, knowledge on crater floor fracturing pertains directly to assessing the duration, spatial extent and mechanisms of advective heat transport of post-impact hydrothermal cells below impact craters as well as the formation of the economically most valuable ore deposits on Earth. Moreover, the patterns and types of crater floor fractures resulting from the analogue experiments may well aid in inferring crustal thicknesses of rocky planetary bodies other than Earth.

• DFG Programme: Research Grants