Brittany A. Erickson and Steven M. Day poster presentation for the Seismological Society of America 2014 Annual Meeting in Anchorage, Alaska

Session: Diverse Mechanisms of Subduction Zone Fault Slip: Exploring the Relationships Among Seismic Rupture, Transient Slip, and Steady Creep

A Provably Stable Finite-Difference Method for Earthquake Cycle Simulations within Subduction Zones
ERICKSON, B. A., San Diego State University, San Diego, CA, USA,; DAY, S. M., San Diego State University, San Diego, CA, USA,
We are developing a computational method for earthquake cycle simulations within complex geometries.  The method is developed for the classical plane-strain problem that can incorporate non-planar fault geometries and material heterogeneities.  The off-fault volume is discretized using finite-differences and coordinate transforms to handle the curvilinear grid that conforms to the fault. All boundary conditions are imposed weakly, yielding a provably stable method.  As a first step towards developing this method, we consider a planar, vertical strike slip fault governed by rate-and-state friction, and load the system at the remote boundaries at the slow, tectonic plate rate. During the long interseismic period we solve the equations for static-equilibrium.  Once an event nucleates we have the option of simulating quasi-dynamic events within the framework, or use the current numerical solution as initial input into the dynamic rupture code SORD that captures the fine details of wave propagation.  An important application for this computational method will be to fault geometries representative of subduction zones, where the earthquake cycle may be strongly influenced by both fault geometry and material property variations.

Wednesday, April 30th / Poster #40 / Cook/Arteaga