EGU25-17710, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-17710
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Nanostructures as indicator for deformation dynamics
Sarah Incel1, Markus Ohl2, Frans Aben3, Oliver Plümper2, and Nicolas Brantut1,4
Sarah Incel et al.
  • 1GFZ Helmholtz-Zentrum für Geoforschung, Potsdam, Germany
  • 2Utrecht University, Utrecht, The Netherlands
  • 3TNO, Utrecht, The Netherlands
  • 4University College London, London, United Kingdom

We aim to determine the feedback between fault dynamics and fault gouge structures by examining gouge structures that formed during rupture and slip of initially intact granite under upper crustal conditions. Experiments were conducted under quasi-static (3·10-5 mm/s), weakly dynamic (0.27 mm/s) and fully dynamic (≫1.5 mm/s) conditions, with or without fluids, and limited slip displacement (max. 4 mm). The extent in gouge amorphisation positively correlates with deformation rate, and we detected evidence of melting, e.g., magnetite nanograins, associated with the highest deformation rates. Gouge nanostructure is directly correlated to power dissipation rather than total energy input. The presence of amorphous material is shown to have no detectable impact on the strength evolution during rupture. We highlight that gouge textures, generally associated with large displacements and/or elevated pressure and temperature conditions, can form during small slip events (Mw <2) in the upper crust from initially intact materials.

How to cite: Incel, S., Ohl, M., Aben, F., Plümper, O., and Brantut, N.: Nanostructures as indicator for deformation dynamics, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17710, https://doi.org/10.5194/egusphere-egu25-17710, 2025.