Subduction earthquake cycles controlled by episodic fluid pressure cycling

In subduction zones, fluids are often invoked to explain slip processes on the megathrust, from great earthquakes slow-slip events and tectonic tremors. However, it is unclear how transient evolution of pore-fluid controlled by depth-dependent variations in hydraulic properties over a broad range timescales concomitant with full spectrum seismic aseismic slip. this study, we leverage newly-developed fully dynamic hydro-mechanical earthquake cycle modeling framework simulate fluid-driven fault By assimilating geological, geophysical, laboratory data physics-based model dynamics, investigate role on-fault controlling predominant mode along megathrust. Results indicate that shear cracks nucleate due competing mechanism between compaction pores self-pressurization inside whereas subsequent propagation ruptures self-sustained solitary pore-pressure waves. While models uniform yield regular cycles complete megathrust ruptures, depth-varying permeability leads emergence complex aperiodic sequences characterized partial aftershocks, Further parameter analysis shows response primarily depends porosity, which turn control poroelastic compaction, storage capacity, diffusion length. Four patterns revealed space, including events, oscillatory decay time, stable creep. Our findings provide new insights into interplay pore-fluid, mechanical, processes, suggest solid-fluid interactions architecture play key megathrusts.