Geophysics Seminar - Allan Rubin, "Merging elastic/frictional and stochastic models of slow slip"

Speaker: Allan Rubin
Professor of Geosciences, Princeton University

Abstract:

Slow slip and nonvolcanic tremor were discovered over 20 years ago, but we still don’t
understand how they are generated, or what distinguishes fault zones that produce slow
slip from those that produce “regular” earthquakes. Models of slow slip tend to come in 2
flavors: Continuum elastic/frictional models, designed to reproduce their slow propagation
speeds and faster “tremor reversals”, and stochastic Brownian walk models, which lack basic
physics but which reproduce various statistical properties of slow slip, including a ∼constant
ratio of radiated seismic energy rate to moment rate. We have been exploring a stochastic
elastic/frictional model that simultaneously reproduces many of the statistical properties
of the stochastic models and the migration properties of continuum models. I’ll end by
describing robust observations of tremor and slow slip that our model fails to reproduce, and
what this might tell us about processes acting in the slow slip source region.