16:30 〜 16:45
[SCG40-20] Investigating Along-Fault Variability in Slow Earthquake Cycles Through a Numerical Approach Utilizing Combined Viscoelastic and Damage Rheological Models
キーワード：Slow earthquake, Complex modeling, Episodic tremor and slip, FEM
Investigating the dynamic interplay of subduction zone seismo-tectonic cycles remains crucial for understanding the complexities of plate interactions. This research delves into the nuanced variations in plate coupling across depths, particularly focusing on the transition between locked surface interfaces and stable slip zones. In contrast to conventional seismic events, slow earthquakes are characterized by silent slips and correlated tectonic tremors.
Traditional seismic modeling often assumes infinitely thin faults with friction laws, but this research departs from traditional rate and state modeling using a volumetric numerical modeling approach, based on a Maxwell elasto-visco-brittle rheology, hence including a representation of damage, with an associated failure criterion. The study investigates the influence of depth-dependent thermo-mechanical conditions on along-fault changes in the inter-plate coupling, shedding light on fault-zone rheology variations.
The numerical simulations systematically examine the impact of model parameters, including viscosity, yield stress, and healing time, on the manifestation of slow slip and tremors. Noteworthy findings indicate that variations in strength significantly affect recurrence intervals and slow slip amplitude, while changes in healing time and viscosity exhibit distinct influences.
Crucially, the model successfully reproduces observed recurrence times, displacement gradients, and synchronous episodes of slow slip and tremors in the initial stages. This physically grounded exploration contributes valuable insights into the spatial distribution of displacement and tremor activities, enhancing our comprehension of the seismic behavior in subduction zones.
Traditional seismic modeling often assumes infinitely thin faults with friction laws, but this research departs from traditional rate and state modeling using a volumetric numerical modeling approach, based on a Maxwell elasto-visco-brittle rheology, hence including a representation of damage, with an associated failure criterion. The study investigates the influence of depth-dependent thermo-mechanical conditions on along-fault changes in the inter-plate coupling, shedding light on fault-zone rheology variations.
The numerical simulations systematically examine the impact of model parameters, including viscosity, yield stress, and healing time, on the manifestation of slow slip and tremors. Noteworthy findings indicate that variations in strength significantly affect recurrence intervals and slow slip amplitude, while changes in healing time and viscosity exhibit distinct influences.
Crucially, the model successfully reproduces observed recurrence times, displacement gradients, and synchronous episodes of slow slip and tremors in the initial stages. This physically grounded exploration contributes valuable insights into the spatial distribution of displacement and tremor activities, enhancing our comprehension of the seismic behavior in subduction zones.