Fig. 6

Schematic model of the plate interface at a subduction zone (modified after Dixon and Moore 2007). Fluid supply to the plate interface promotes hydration reactions, forming clay minerals, which influence the frictional properties of the subducting plate. The clay-rich regions of the interface could be weakly coupled and act as non-asperity, whereas the unaltered patches remain strongly coupled and have the potential to generate megathrust earthquakes. Schematic model of the seismic cycle for subduction zone earthquakes, showing co-seismic slip generated by the unhydrated strongly coupled patches and post-seismic slip controlled by the weakly coupled hydrated patches