Articles | Volume 16, issue 10
https://doi.org/10.5194/se-16-1205-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-16-1205-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
27 Oct 2025
Research article |
| 27 Oct 2025
| 27 Oct 2025
Dissolution–precipitation creep in polymineralic granitoid shear zones in experiments – Part 2: Rheological parameters
Natalia Nevskaya
CORRESPONDING AUTHOR
Institute of Geological Sciences, University of Bern, Bern, 3012, Switzerland
Department of Earth & Planetary Sciences, Yale University, New Haven, CT 06511, USA
Alfons Berger
Institute of Geological Sciences, University of Bern, Bern, 3012, Switzerland
Holger Stünitz
Department of Geology, Tromsø University, Tromsø, 9037, Norway
Institut des Sciences de la Terre d'Orléans, Université d'Orléans, Orléans, 45100, France
Markus Ohl
Department of Earth Sciences, Utrecht University, Utrecht, 3584 CB, Netherlands
Oliver Plümper
Department of Earth Sciences, Utrecht University, Utrecht, 3584 CB, Netherlands
Faculty of Geosciences, University of Bremen, 28334 Bremen, Germany
Marco Herwegh
Institute of Geological Sciences, University of Bern, Bern, 3012, Switzerland
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Short summary
To date, there remains a deficiency in rheological parameters for polymineralic rocks to be used in models, e.g., for strain localization in the Earth's continental middle crust. We provide a first estimate on grain size and stress sensitivity of experimentally deformed natural fine-grained granitoid rocks. Extrapolation of these parameters predicts a switch in the weakest material as a function of grain size and deformation mechanism from coarse monomineralic quartz to fine polymineralic rocks.
To date, there remains a deficiency in rheological parameters for polymineralic rocks to be used...
