The inner workings of the earthquake cycle: New insight from microstructural & textural analysis of natural fault rocks I

Identification of the mechanochemical processes occurring during fault slip is of fundamental importance to understand earthquake nucleation and propagation. We will use textural analysis to explore the micromechanical processes occurring during and after slip at seismic rates utilizing an unique sample set of active fault samples from the Central Apennines, Italy, which has been subject to devastating earthquakes. These slip zones are characterized by extreme grain size reduction necessitating the textural analysis capabilities available at ISIS. Preliminary microstructural and GPS data show that brittle, seismic failure is followed by interseismic periods where crystal plasticity i.e. ductile flow may occur. Outcomes will allow us to evaluate the significance of ductile flow during the earthquake cycle and therefore advance our understanding of fault dynamics and seismic hazard.