Presentation by Dr Eric Beauce from SGT, Lamont-Doherty Earth Observatory.
How, where and when do large earthquakes develop? Building the future of large-scale rock physics
Large earthquakes are among the most devastating geohazards, often triggering cascading events such as tsunamis, landslides, and soil liquefaction. More than a century of observational seismology and geodesy has taught us that large earthquakes result from a cycle of accumulation and release of deformation along major plate boundaries. Despite this general understanding of the “seismic cycle,” we are not yet capable of making useful predictions regarding the timing, location, or magnitude of future large events.
This stands in stark contrast to laboratory analogs of earthquakes, which are consistently preceded by observable precursory phenomena. If rock failure involves a “preparation phase” in the laboratory, why can’t we observe it in the field? Improving our ability to forecast large earthquakes is inherently a matter of upscaling rock physics from the millimeter scale of laboratory samples to the hundred-kilometer scale of natural faults.
In this talk, I present a research program based on cutting-edge observational techniques that address fundamental questions in earthquake physics and fault mechanics. These tools enable us to detect the preparation phase of large earthquakes and better understand fault behavior throughout the seismic cycle. I demonstrate how the subtle response of faults to small, non-tectonic stress perturbations offers new constraints on fault physics and provides a window into their physical state. The success of this approach extends beyond earthquakes to other geosystems, such as volcanoes. To reinforce our comprehension of the complex physics of crustal deformation, I study the effects of a wide range of stress perturbations on faults, as well as the patterns and mechanisms of earthquake interactions. Finally, I discuss how to complement these seismicity-based analyses with novel approaches enabled by fiber-optic data and advances in artificial intelligence. Altogether, my work aims to advance our fundamental understanding of the Earth and our capacity to anticipate major geohazards.
Zoom Link:
https://columbiauniversity.zoom.us/j/6578604763
