Figure 6

(A) Horizontal and vertical components associated with the October 30^th 2016 M_w 6.5 mainshock (data after⁴). Notice the larger coseismic vertical displacement, in agreement with the vertical maximum stress tensor (σ₁). The fault dip correctly represents the vector sum of the horizontal and vertical components of the displacement. (B) Surface rupture associated with the two seismic events⁶⁸. (C) Numerical modelling of interseismic and coseismic deformation in a simplified brittle upper crust and visco-plastic lower crust. During the interseismic the fault is locked in the upper crust, whereas is shearing in steady state in the lower crust. A dilated volume forms above the brittle-ductile transition to accommodate the strain partitioning. At the coseismic stage, the fault hangingwall collapses and recover the previously formed dilation. See shear stress associated with the two stages (modified after⁵⁰).