Micro-scale dependent, time- and space-evolving rheologies: the key for generating strain localization in the Earth

2026-07-22

"RhEoVOLUTION proposes a ""revolution"" in how we define rheology (the equations relating forces to deformation) in geodynamical models. It aims at predicting the onset and evolution of strain localization. Modeling spontaneous ductile strain localization has been impossible so far, because it depends on processes active at the mm scale, which cannot be explicitly simulated in geodynamical models. The tools we designed and propose to develop in RhEoVOLUTION will make it possible. We will bridge scales and model how heterogeneity and anisotropy in the mechanical behavior of rocks control strain localization from the cm to the tens of km scale in the Earth. To do so, we will: 1. describe the heterogeneity of mechanical behavior of rocks deforming by dislocation creep by stochastic parameterizations of the rheology; 2. constrain these parameterizations by experiments with in-situ follow-up of the strain evolution and mesoscale models; 3. accelerate the calculation of the evolution of anisotropy during deformation by using supervised machine-learning; 4. quantify feedbacks between the main processes producing strain localization by comparing the predictions of models parameterized to simulate these processes to observations in natural shear zones. RhEoVOLUTION will empower the geodynamics community with a predictive tool for strain localization. It will provide explanations for localized deformation in intraplate domains and predictions of the evolution of shear zones in extensional and convergent plate margins, enhancing our understanding of the architecture of passive margins and mountain belts. We postulate it will allow modeling the most evident expression of strain localization on Earth: Plate Tectonics, that is still a challenge >50 years after the scientific revolution that established this paradigm. The tools developed in RhEoVOLUTION will also allow predicting ductile strain localization in ice and metals with possible applications in glaciology and metallurgy."

France

2026-02-15