Landers 1992 “Reloaded”: Integrative Dynamic Earthquake Rupture Modeling
KAUST DepartmentComputational Earthquake Seismology (CES) Research Group
Earth Science and Engineering
Earth Science and Engineering Program
Physical Science and Engineering (PSE) Division
Embargo End Date2019-10-30
Permanent link to this recordhttp://hdl.handle.net/10754/656204
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AbstractThe 1992 Mw 7.3 Landers earthquake is perhaps one of the best studied seismic events. However, many aspects of the dynamics of the rupture process are still puzzling, for example, the rupture transfer between fault segments. We present 3-D spontaneous dynamic rupture simulations, incorporating the interplay of fault geometry, topography, 3-D rheology, off-fault plasticity, and viscoelastic attenuation. Our preferred scenario reproduces a broad range of observations, including final slip distribution, shallow slip deficits, and mapped off-fault deformation patterns. We demonstrate good agreement between synthetic and observed waveform characteristics and associated peak ground velocities. Despite very complex rupture evolution, ground motion variability is close to what is commonly assumed in Ground Motion Prediction Equations. We examine the effects of variations in modeling parameterization within a suite of scenarios including purely elastic setups and models neglecting viscoelastic attenuation. Source dynamics of all models include dynamic triggering over large distances and direct branching; rupture terminates spontaneously on most of the principal fault segments. Sustained dynamic rupture of all fault segments in general, and rupture transfers in particular, constrain amplitude and orientation of initial fault stresses and friction. We conclude that physically consistent in-scale earthquake rupture simulations can augment earthquake source observations toward improving the understanding of earthquake source physics of complex, segmented fault systems.
CitationWollherr, S., Gabriel, A., & Mai, P. M. (2019). Landers 1992 “Reloaded”: Integrative Dynamic Earthquake Rupture Modeling. Journal of Geophysical Research: Solid Earth, 124(7), 6666–6702. doi:10.1029/2018jb016355
SponsorsWe thank Christopher Milliner for providing the left part of Figure 10 which is similar to Figure 7 in Milliner et al. (2015). All data used are listed in the paper. Simulation results were obtained using the open-source software package SeisSol, freely available at github.com/SeisSol/SeisSol. All initial conditions and results generated by our simulations are available upon request. Computing resources were provided by the Leibniz Supercomputing Centre (LRZ, projects pr45fi and pr63qo on SuperMUC). The work presented in this paper was supported by the German Research Foundation (DFG) (projects KA 2281/4-1, GA 2465/2-1, BA 3529/6-1), by the Bavarian Competence Network for Technical and Scientific High Performance Computing (KONWIHR), project GeoPF (Geophysics for PetaFlop Computing), by the Volkswagen Foundation (project ASCETE—Advanced Simulation of Coupled Earthquake-Tsunami Events, grant 88479), by the European Union's Horizon 2020 research and innovation program under grant agreement 671698 and 823844 as well as by King Abdullah University of Science and Technology (KAUST) in Thuwal, Saudi Arabia, under grant ORS-2016-CRG5-3027-04 and OSR-CRG2017-3389. P. M. Mai is sponsored through KAUST research fund BAS/1339-01-01.
PublisherAmerican Geophysical Union (AGU)