Presentation by Dr. Alexis Saez Uribe from Caltech.
Earthquake nucleation, arrest, and the interactions between aseismic and seismic slips: integrating theory, experiments, and observations.
How do earthquakes start and stop? What controls whether faults slip slowly or rapidly, and how do these modes of slip interact? These questions lie at the core of earthquake physics and directly shape seismic hazard by governing when, where, and how large earthquakes occur. In this talk, I will present recent advances in our understanding of the physical processes underlying these fundamental questions. First, I will focus on subsurface borehole fluid injections—widely used in the geo-energy sector for hydrocarbon production and geothermal energy—as a natural laboratory to investigate earthquake nucleation under controlled forcing. I will discuss mechanical controls on earthquake timing and highlight recent efforts to test theoretical predictions through laboratory experiments of analog earthquake ruptures. Second, I will examine the mechanics of earthquake barriers—regions that promote earthquake arrest—and explore how stress changes imparted by past earthquakes may shape fault segmentation patterns observed in historical and paleoseismic records. Lastly, after briefly reviewing recent findings on the controls governing the interaction between aseismic and seismic slip, I will conclude by highlighting key open questions and future research directions in this area. I will emphasize opportunities to integrate theory and laboratory experiments using rock analog materials to develop physics-based models that advance our understanding of earthquake physics in both natural and anthropogenic settings.
