Aftershock sequence simulations using synthetic earthquakes and rate-state seismicity formulation
Heming Xu1,2, Yifeng Cui1, James H. Dieterich2, Keith Richards-Dinger2, Efecan Poyr1, Dong Ju Choi1
1 San Diego Supercomputer Center, University of California, San Diego, CA, USA 2 Department of Earth Sciences, University of California, Riverside, CA, USA
Aftershock sequence simulations using synthetic earthquakes and rate-state seismicity formulation
Heming Xu1,2, Yifeng Cui1, James H. Dieterich2, Keith Richards-Dinger2, Efecan Poyr1, Dong Ju Choi1
1 San Diego Supercomputer Center, University of California, San Diego, CA, USA 2 Department of Earth Sciences, University of California, Riverside, CA, USA
摘要We use an efficient earthquake simulator that incorporates rate-state constitutive properties and uses boundary element method to discretize the fault surfaces, to generate the synthetic earthquakes in the fault system. Rate-and-state seismicity equation is subsequently employed to calculate the seismicity rate in a region of
interest using the Coulomb stress transfer from the main shocks in the fault system. The Coulomb stress transfer is obtained by resolving the induced stresses due to the fault patch slips onto the optimal-oriented fault planes. The example results show that immediately after a main shock the aftershocks are concentrated in the vicinity of the rupture area due to positive stress transfers and then disperse away into the surrounding region toward the background rate distribution. The number of aftershocks near the rupture region is found to decay with time as Omori aftershock decay law predicts. The example results demonstrate that the rate-and-state fault system earthquake simulator and the seismicity equations based on the ratestate friction nucleation of earthquake are well posited to characterize the aftershock distribution in regional assessments of earthquake probabilities.
Abstract：We use an efficient earthquake simulator that incorporates rate-state constitutive properties and uses boundary element method to discretize the fault surfaces, to generate the synthetic earthquakes in the fault system. Rate-and-state seismicity equation is subsequently employed to calculate the seismicity rate in a region of
interest using the Coulomb stress transfer from the main shocks in the fault system. The Coulomb stress transfer is obtained by resolving the induced stresses due to the fault patch slips onto the optimal-oriented fault planes. The example results show that immediately after a main shock the aftershocks are concentrated in the vicinity of the rupture area due to positive stress transfers and then disperse away into the surrounding region toward the background rate distribution. The number of aftershocks near the rupture region is found to decay with time as Omori aftershock decay law predicts. The example results demonstrate that the rate-and-state fault system earthquake simulator and the seismicity equations based on the ratestate friction nucleation of earthquake are well posited to characterize the aftershock distribution in regional assessments of earthquake probabilities.
基金资助:The NSF Frontiers in Earth-SystemDynamics (EAR-1135455), The computational work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Natural Science Foundation grant No. OCI-1053575. This research is part of the Blue Waters sustained-petascale computing project, which is supported by the National Natural Science Foundation (award No. OCI 07-25070) and the state of Illinois.
通讯作者:
Heming Xu
E-mail: h1xu@ucsd.edu
引用本文:
Heming Xu, Yifeng Cui, James H. Dieterich, Keith Richards-Dinger, Efecan Poyr, Dong Ju Choi. Aftershock sequence simulations using synthetic earthquakes and rate-state seismicity formulation[J]. 《地震学报》英文版, 2014, 27(4): 401-410.
Heming Xu, Yifeng Cui, James H. Dieterich, Keith Richards-Dinger, Efecan Poyr, Dong Ju Choi. Aftershock sequence simulations using synthetic earthquakes and rate-state seismicity formulation. Earthquake Science, 2014, 27(4): 401-410.
