Future Directions and Capabilities of Simulators Jim Dieterich

Summary of some advantages of simulators relative to current UCERF methods Integrated self-consistent framework for generating an earthquake rate model Properly captures intrinsic relations between stress and fault slip in 3D systems and avoids the dubious use of point characterizations of spatially varying properties (stress, slip, time since last slip, clock reset) Clustering is modeled deterministically and tied to constitutive parameters and evolving stress conditions Framework for characterizing regional fluctuations of seismicity rates – interpretation of empirical model Non-linear stressing from interactions with deep creeping zone and viscoelasticity in some models Moment balancing issues are eliminated No assumptions are made regarding characteristic earthquakes (pro or con) Rupture jumps and branching occur spontaneously Coupling factor and aseismic creep reduction of moment

Future Directions and Capabilities Cascadia models (Eqs, creep, slow slip events) Integration with deformation models High-performance computing (all California faults at 100m?) Integration with simulations of rupture dynamics and ground motions Off-fault seismicity Triggering by tides and earthquakes SCEC4 special study areas

Modified from McCrory et al. (2006)

Number of elements BIG EVENTS Patchy slip Indistinct initiation Indistinct end

Number of elements Rapid Tremor Reversals (RTRs Houston et al., submitted

Number of elements

Future Directions and Capabilities Cascadia models (Eqs, creep, slow slip events) Integration with deformation models High-performance computing (all California faults at 100m?) Integration with simulations of rupture dynamics and ground motions Off-fault seismicity Triggering by tides and earthquakes SCEC4 special study areas

Future Directions and Capabilities Cascadia models (Eqs, creep, slow slip events) Integration with deformation models High-performance computing (all California faults at 100m?) Integration with simulations of rupture dynamics and ground motions Off-fault seismicity Triggering by tides and earthquakes SCEC4 special study areas

Future Directions and Capabilities Cascadia models (Eqs, creep, slow slip events) Integration with deformation models High-performance computing (all California faults at 100m?) Integration with simulations of rupture dynamics and ground motions Off-fault seismicity Triggering by tides and earthquakes SCEC4 special study areas

Future Directions and Capabilities Cascadia models (Eqs, creep, slow slip events) Integration with deformation models High-performance computing (all California faults at 100m?) Integration with simulations of rupture dynamics and ground motions Off-fault seismicity Triggering by tides and earthquakes SCEC4 special study areas

Off-Fault Aftershock simulations Landers Earthquake (1992, Mw = 7.3) Off-fault earthquake rate , Aftershock rate following a stress step DS Dieterich, JGR (1994) Dieterich, Cayol, Okubo, Nature, (2000) Heterogeneous orientations of fault planes Smith and Dieterich (in Prep)

Background seismicity and focal mechanisms on a population of planes

Future Directions and Capabilities Cascadia models (Eqs, creep, slow slip events) Integration with deformation models High-performance computing (all California faults at 100m?) Integration with simulations of rupture dynamics and ground motions Off-fault seismicity Triggering by tides and earthquakes SCEC4 special study areas