Thermally activated static friction can explain earthquake interactions

A team of ISTerre scientists, both in Grenoble and Chambéry, recently proposed a model of earthquakes that incorporates a minimal number of well-established, fundamental physical mechanisms, namely static friction in its simplest form, i.e. without any empirical formulation for time-dependence, elastic stress transfers, and thermal activation. Using this model, they were able to accurately reproduce many aspects of seismicity, including mainshock-aftershock sequences, while precursory signals to large earthquakes are elusive. In addition, introducing temperature in a physically meaningful way enables to interpret the range of mechanical behaviors observed e.g. along subduction faults at increasing depths and so temperatures, from locked faults slipping through a succession of earthquakes, including some very large, in the upper, “cold” part of a subduction slab, to faults creeping steadily and “silently” in the lower, “warm” sections.