Simulation Based Earthquake Forecasting with RSQSim

Jacquelyn J. Gilchrist, Thomas H. Jordan, James H. Dieterich, & Keith B. Richards-Dinger

Published July 29, 2016, SCEC Contribution #6404, 2016 SCEC Annual Meeting Poster #316

We are developing a physics-based forecasting model for earthquake ruptures in California. We employ the 3D boundary element code RSQSim to generate synthetic catalogs with millions of events that span up to a million years. The simulations incorporate rate-state fault constitutive properties in complex, fully interacting fault systems. The Unified California Earthquake Rupture Forecast Version 3 (UCERF3) model and data sets are used for calibration of the catalogs and specification of fault geometry. Fault slip rates match the UCERF3 geologic slip rates and catalogs are tuned such that earthquake recurrence matches the UCERF3 model. Utilizing the Blue Waters Supercomputer, we produce a suite of million-year catalogs to investigate the epistemic uncertainty in the physical parameters used in the simulations. In particular, values of the rate- and state-friction parameters a and b, the initial shear and normal stress, as well as the earthquake slip speed, are varied over several simulations. In addition to testing multiple models with homogeneous values of the physical parameters, the parameters a, b, and the normal stress are varied with depth as well as in heterogeneous patterns across the faults. Cross validation of UCERF3 and RSQSim is performed within the SCEC Collaboratory for Interseismic Simulation and Modeling (CISM) to determine the affect of the uncertainties in physical parameters observed in the field and measured in the lab, on the uncertainties in probabilistic forecasting. We are particularly interested in the short-term hazards of multi-event sequences due to complex faulting and multi-fault ruptures.

Key Words
Earthquake Simulators, Earthquake Forecasting

Citation
Gilchrist, J. J., Jordan, T. H., Dieterich, J. H., & Richards-Dinger, K. B. (2016, 07). Simulation Based Earthquake Forecasting with RSQSim. Poster Presentation at 2016 SCEC Annual Meeting.

Related Projects & Working Groups
Collaboratory for Interseismic Simulation and Modeling (CISM)