On the scale dependence in the dynamics of frictional rupture: Constant fracture energy versus size-dependent breakdown work

Potential energy stored during the inter-seismic period by tectonic loading around faults is released earthquakes as radiated energy, frictional dissipation and fracture energy. The latter of first importance since it expected to control nucleation, propagation arrest seismic rupture. On one side, seismological estimated for natural (commonly called breakdown work) ranges between 1 J/m2 tens MJ/m2 largest events, shows a clear slip dependence. other recent experimental studies highlighted that, concerning rupture experiments, material property (energy required break fault interface) independently size event, i.e. slip. To reconcile these contradictory observations definitions, we performed stick-slip analog earthquakes, in bi-axial shear configuration. We through both Linear Elastic Fracture Mechanics (LEFM) Cohesive Zone Model (CZM) integration near-fault stress-slip evolution. show at scale our weakening divided into near-tip weakening, corresponding an few J/m2, consistent with LEFM CZM, long-tailed larger not localized tip, increasing Through numerical simulations, demonstrate that only controls initiation can enhance allow overcome stress heterogeneity along fault. conclude origin estimates work could be related dissipated rather than near tip.