Fully Dynamic Earthquake Cycle Modeling to Explore Interactions Between Large Earthquakes and Slow Slip Events on Heterogeneous Faults
Description:
Recent observations show interactions between large earthquakes and slow slip events (SSEs). To understand physics underlying these observations, we need to resort to physics-based models that can capture both spontaneously dynamic rupture during large earthquakes and quasi-static deformation processes (including slow slip events) between earthquakes. These models cross multiple time- and length-scales. In this study, we apply a recently developed method for this type of models, a Finite Element Method (FEM) dynamic earthquake simulator, EQdyna, to perform fully dynamic earthquake cycle modeling on a shallow-dipping subduction plane to investigate interactions between large earthquakes and SSEs. The method distinguishes itself from classical, quasi-dynamic earthquake simulators in the community that do not capture spontaneous rupture propagation. We are particularly interested in how heterogenous frictional properties on the fault plane dictate generation of large earthquakes and SSEs and their interactions over multiple earthquake cycles. In our models, multiple asperities with unstable slip frictional properties are distributed on a subduction plane with conditional stable frictional properties. We vary the asperities’ sizes and locations to explore their effects. Our preliminary results successfully reproduce depth-dependent modes of SSEs observed at the Hikurangi subduction zone in New Zealand that shallower SSEs happen more frequently with shorter durations at low stress. Notably, our findings elucidate distinct loading effects of SSEs associated with small asperities at different depths on large earthquakes. In addition, models with numerous tiny asperities reveal a higher SSE occurrence frequency, suggesting these areas act as barriers for large earthquake rupture propagation.
Session: From Geodynamics to Earthquake Rupture, Models That Cross Time- and Length-Scales - I
Type: Oral
Date: 5/3/2024
Presentation Time: 05:15 PM (local time)
Presenting Author: Zizhuang
Student Presenter: Yes
Invited Presentation:
Authors
Zizhuang Tang Presenting Author Corresponding Author zztang@tamu.edu Texas A&M University |
Benchun Duan bduan@tamu.edu Texas A&M University |
Qingjun Meng qingjun23@g.ucla.edu University of California, Los Angeles |
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Fully Dynamic Earthquake Cycle Modeling to Explore Interactions Between Large Earthquakes and Slow Slip Events on Heterogeneous Faults
Category
From Geodynamics to Earthquake Rupture, Models That Cross Time- and Length-Scales