Parametrizing Physics-Based Earthquake Simulations
- 153 Downloads
Utilizing earthquake source parameter scaling relations, we formulate an extensible slip weakening friction law for quasi-static earthquake simulations. This algorithm is based on the method used to generate fault strengths for a recent earthquake simulator comparison study of the California fault system. Here we focus on the application of this algorithm in the Virtual Quake earthquake simulator. As a case study we probe the effects of the friction law’s parameters on simulated earthquake rates for the UCERF3 California fault model, and present the resulting conditional probabilities for California earthquake scenarios. The new friction model significantly extends the moment magnitude range over which simulated earthquake rates match observed rates in California, as well as substantially improving the agreement between simulated and observed scaling relations for mean slip and total rupture area.
KeywordsVirtual Quake Virtual California earthquake simulations
We would like to thank Prof. Steven N. Ward for his initial version of this stress drop algorithm, and for his advice guiding the development of this study. This research was supported by National Aeronautics and Space Administration (NASA) Earth and Space Science fellowship number NNX11AL92H. Virtual Quake is hosted by the NSF-supported Computational Infrastructure for Geodynamics (CIG). Virtual Quake is open source scientific software, is available for download and comes with a user manual (Schultz et al. 2016). URL:http://geodynamics.org/cig/software/vq/.
- ANSS. 2016. UC Berkeley Seismological Laboratory. http://www.quake.geo.berkeley.edu/anss/catalog-search.html. Accessed 25 January 2016.
- Kanamori, H., & Anderson, D. L. (1975). Theoretical basis of some empirical relations in seismology. Bulletin of the Seismological Society of America, 65(5), 1073–1095.Google Scholar
- Okada, Y. (1992). Internal deformation due to shear and tensile faults in a half-space. Bulletin of the Seismological Society of America, 82(2), 1018–1040.Google Scholar
- Rundle, J. B. (1988a). A physical model for earthquakes: 1. Fluctuations and interactions. Journal of Geophysical Research: Solid. Earth, 93(B6), 6237–6254.Google Scholar
- Rundle, J. B. (1988b). A physical model for earthquakes: 2. Application to southern California. Journal of Geophysical Research: Solid. Earth, 93(B6), 6255–6274.Google Scholar
- Rundle, J. B., Rundle, P. B., Donnellan, A., Turcotte, D. L., Shcherbakov, R., Li, P., et al. (2005). A simulation-based approach to forecasting the next great san francisco earthquake. Proceedings of the National Academy of Sciences of the United States of America, 102(43), 15363–15367.CrossRefGoogle Scholar
- Rundle, P., Rundle, J., Tiampo, K., Donnellan, A., & Turcotte, D. (2006b). Virtual california: Fault model, frictional parameters, applications. In Computational Earthquake Physics: Simulations, Analysis and Infrastructure, Part I, Pageoph Topical Volumes (pp. 1819–1846). Birkhäuser, Basel.Google Scholar
- Scholz, C. H. (1990). The Mechanics of Earthquakes and Faulting. Cambridge: Cambridge University Press.Google Scholar
- Schultz, K. W., Sachs, M. K., Heien, E. M., Rundle, J. B., Turcotte, D. L., & Donnellan, A. (2014). Simulating gravity changes in topologically realistic driven earthquake fault systems: First results. Pure and Applied Geophysics (in press). doi: 10.1007/s00024-014-0926-4.
- Schultz, K. W., Sachs, M. K., Yoder, M. R., Rundle, J. B., Turcotte, D. L., Heien, E. M., et al. (2015). Virtual quake: Statistics, co-seismic deformations and gravity changes for driven earthquake fault systems. International Association of Geodesy Symposia, 1–9, doi: 10.1007/1345_2015_134.
- Schultz, K. W., Heien, E. M., Sachs, M. K., Wilson, J. M., Yoder, M. R., Rundle, J. B., & Turcotte, D. L. (2016). Virtual Quake User Manual, Version 2.1.2. Davis, California: Computational Infrastructure for Geodynamics. https://geodynamics.org/cig/software/vq/vq_manual_2.1.2.pdf.
- Wells, D. L., & Coppersmith, K. J. (1994). New empirical relationships among magnitude, rupture length, rupture width, rupture area, and surface displacement. Bulletin of the Seismological Society of America, 84(4), 974–1002.Google Scholar
- Yikilmaz, M. B., Turcotte, D. L., Yakovlev, G., Rundle, J. B., & Kellogg, L. H. (2010). Virtual california earthquake simulations: simple models and their application to an observed sequence of earthquakes. Geophysical Journal International, 180(2), 734–742. doi: 10.1111/j.1365-246X.2009.04435.x.
- Yoder, M. R., Schultz, K. W., Heien, E. M., Rundle, J. B., Turcotte, D. L., Parker, J. W., et al. (2015). The Virtual Quake earthquake simulator: a simulation-based forecast of the El Mayor-Cucapah region and evidence of predictability in simulated earthquake sequences. Geophysical Journal International, 203(3), 1587–1604. doi: 10.1093/gji/ggv320.CrossRefGoogle Scholar