The state of pore fluid pressure and 3D megathrust earthquake dynamics

Abstract

Very high coseismic pore fluid pressure at 97 % of the lithostatic pressure supported by dynamic rupture modeling.• Very high coseismic pore fluid pressure causes peak slip and peak slip rate at shallower depths, underscoring the importance of characterizing near-trench conditions to characterize megathrust hazard.• Apparent co-seismic principal stress rotations and heterogeneous absolute postseismic stress state are consistent with a variety of aftershock focal mechanisms.