A perspective on the theory and simulation of non-planar fault networks
The modelling of earthquake cycle, including stress build-up during inter-seismic stage, the nucleation of earthquakes or slow slip events, their propagation and their arrest before building up again the stress, has undergone rapid improvement over the last decade. Networks of non-planar faults are a key ingredient to better understand earthquake mechanics, yet there is a lack of theoretical framework describing the effect of fault geometry, as well as efficient numerical approaches for modelling complex fault networks.
In this work, I will present you a way to isolate theoretically the effect of non-planarity of fault on the tractions. It relies on the expansion of the traction around a non-planar fault, using the boundary element method, when assuming that the slope of the fault is small. This assumption allows to derive a scaling between the slip distribution along the fault and the fault geometry itself. These theoretical predictions have recently been validated by slip measurement of laboratory earthquakes on PMMA interfaces, which opens new opportunities to understand slip distribution in paleoseismology or to invert fault geometry from the the inversion of slip after an earthquake.
More generally, the boundary element method provides a particularly well-suited framework for modelling interacting non-planar fault networks. In this perspective, I will briefly discuss recent advanced based on boundary element method to investigate fluid diffusion across fault networks and to simulate fully-dynamic earthquake cycle on network of fauts at regional scale. Thanks to efficient numerical implementations, these approaches are extremely fast and enable simulations of complex fault networks to be performed on standard laptop computers.
Overall, this perspective highlights how combining theoretical developments with efficient boundary-element simulations opens new possibilities for exploring earthquake mechanics in geometrically complex fault systems, and paves the way for fast, physics-based modelling of large-scale non-planar fault networks.
Short Bio: I am originally from Auvergne, a country-side region in central France known for its volcanoes, the water “Volvic”, and the company “Michelin”. I pursued my studies in Clermont-Ferrand, Nancy, and Paris, beginning in geotechnical engineering before developing a strong interest in sismology. My curiosity for seismic phenomena then took me to Japan, where I spent five years working first at the University of Tokyo and later at the National Research Institute for Earth Science and Disaster Resilience (NIED).
My research has focused on efficient ways of running earthquake simulations, with a focus on non-planar fault geometry and interaction of fault networks, the understanding of fluid-injection–induced, and finally the detection of distinctive seismic signals called tremors.
Outside of work, you’ll most likely find me hanging out with my family, climbing rock cliffs or hiking in the mountains, always happy to trade computer for outdoor fresh air and good views.
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