Nanostructures as indicator for deformation dynamics.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41360815.
- Also identified by DOI 10.1038/s41467-025-67150-4 and PMC identifier 12686469.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
We determine the feedback between fault dynamics and fault gouge structures by examining gouge structures that form during rupture and slip of initially intact granite under upper crustal conditions. Experiments were conducted under quasi-static (3 × 10<sup>-5</sup> mm/s), weakly dynamic (0.27 mm/s) and fully dynamic (≫1.5 mm/s) slip conditions, with or without fluids, and limited slip displacement (max. 4 mm). The extent in gouge amorphization positively correlates with deformation rate, and we detect 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 has 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.