Ricardo Taborda

The Big Ten project is generating a hierarchy of simulations for ten of the most probable large (M > 7) ruptures in Southern California, with the objective of understanding how source directivity, rupture complexity, and basin effects control ground motions. The ruptures and moment-magnitudes are selected from events with relatively high probability rates in the UCERF2 model. Feedback on and refinement of the selected event set from the SCEC community is encouraged. The event set is being used to coordinate multiple types of large-scale simulations (requiring high performance computing), as well as multiple groups of researchers around a common set of earthquake scenarios. The geoscience goals of the Big Ten project are to: (1) Understand the roles of source directivity, rupture complexity, and basin effects on ground motions, and evaluate how these factors control the CyberShake hazard curves; (2) Improve PetaSHA simulation capabilities by incorporating new codes that can model geologic complexities including topography, geologic discontinuities, and source complexities such as irregular, dipping, and offset faults; (3) Use dynamic rupture simulations to investigate the effects of realistic friction laws, geologic heterogeneities, and near-fault stress states on seismic radiation and thereby improve pseudo-dynamic rupture models of hazardous earthquakes; and (4) Use realistic earthquake simulations to evaluate static and dynamic stress transfer and assess their effects on strain accumulation, rupture nucleation, and stress release. Examples of some preliminary Big Ten simulations will be displayed.