Dept. of Geosciences Colloquium: Thermal weakening leads to unconventional singularities during laboratory earthquakes
Francois Passelègue, GeoAzur, Université Côte d’Azur, Nice
The analogy between earthquakes (i.e. frictional ruptures) and shear crack motions is commonly used to better investigate and understand the mechanics and occurrence of such natural phenomena. However, if on one side experimental works showed how classical shear cracks, obeying to a square root singularity, describe the onset of frictional ruptures, on the other side discrepancies related to the definition of the breakdown work are not yet fully solved. Here, we present the results of experiments highlighting evidence of frictional rupture driven by enhanced thermal weakening. In such conditions, rupture fronts present unconventional singularity order and a slip dependent energy release rate. This work shows, from an experimental point of view, the presumable unconventional nature of earthquakes, and solves the discrepancies between breakdown work and fracture energy.
Event Organizers: Dr. Roy Barkan and Dr. Asaf Inbal