Dept. of Geosciences Colloquium: The physics of earthquake nucleation and faulting: From slip-pulses to frictional rupture

Abstract:

The onset of rapid/violent slip along frictional faults, the process of "earthquake nucleation'', and the subsequent spatiotemporal faulting dynamics, play important roles in earthquake physics. In this talk, I will provide an overview of our recent progress in relation to these topics. First, the existence and stability of slip-pulses, i.e. of spatially compact propagating frictional rupture, will be discussed. Second, the idea that unstable slip-pulses may serve as "critical nuclei" for earthquakes along initially quiescent faults, in a non-equilibrium analogy to equilibrium first-order phase transitions, will be discussed. Finally, the origin of stress drops – one of the few remotely observable parameters in earthquake physics – in the post-nucleation faulting dynamics will be elucidated in light of the relations between frictional rupture and ordinary cracks.

References:

Unstable slip pulses and earthquake nucleation as a non-equilibrium first-order phase transition

Physical Review Letters 121, 234302 (2018)

The emergence of crack-like behavior of frictional rupture: The origin of stress drops

Physical Review X, in press (2019). Available at: arXiv:1906.11533

Event Organizers: Dr. Roy Barkan and Dr. Asaf Inbal