A rock-centric framework for rupture dynamics and its applications in Southern California

Binhao Wang, Mingqi Liu, Baoning Wu, Sezim E. Guvercin, Lei Zhang, Zekang Yang, Caroline Seyler, John P. Platt, & Sylvain D. Barbot

Submitted September 7, 2025, SCEC Contribution #14367, 2025 SCEC Annual Meeting Poster #TBD

The frictional properties of rocks embedded in fault zones critically influence earthquake nucleation and rupture propagation. Despite detailed knowledge of regional geology and accumulating laboratory constraints on rock friction, we still lack a systematic framework connecting laboratory-derived rock friction properties to kilometer-scale earthquake processes. Here, we present such a framework. We first characterize the frictional behavior of Southern California basement rocks (granodiorite, diorite, anorthosite, gneiss, schist) under brittle-to-flow conditions (100–500°C) using triaxial deformation experiments. These experiments reveal multi-regime frictional behaviors varying systematically with temperature and slip rate, well captured by physics-based constitutive laws allowing extrapolations to natural fault conditions. Through earthquake cycle simulations, we demonstrate how lithology and rheology control diverse fault slip behaviors including slow-to-fast earthquakes, shallow slip deficits without interseismic creep, and crustal embrittlement. Our simulations reproduce first-order behaviors of two significant Southern California earthquakes. This rock-centric framework bridges laboratory and field constraints with crustal-scale ruptures, offering next-generation models for advancing earthquake physics and improving seismic hazard forecasts.

Key Words
rock friction, framework, earthquake cycle, California

Citation
Wang, B., Liu, M., Wu, B., Guvercin, S. E., Zhang, L., Yang, Z., Seyler, C., Platt, J. P., & Barbot, S. D. (2025, 09). A rock-centric framework for rupture dynamics and its applications in Southern California. Poster Presentation at 2025 SCEC Annual Meeting.


Related Projects & Working Groups
Fault and Rupture Mechanics (FARM)