Exploring the sensitivity of multiscale seismic cycle simulations to material heterogeneities.

Christodoulos Kyriakopoulos, Keith B. Richards-Dinger, & James H. Dieterich

Published August 15, 2016, SCEC Contribution #6996, 2016 SCEC Annual Meeting Poster #322

We are presenting preliminary results on the estimation of the effects of variable material properties in the earthquake simulator RSQSim (Richards-Dinger and Dieterich, 2012). In order to do that we are calculating elastostatic solutions (Green’s functions) in a heterogeneous medium using the Finite Element (FE) code Defmod (Ali, 2014) instead of the analytical solutions of Okada (1992). The investigated region is a ~400 x 400 km area centered on the Anza zone in southern California. The fault geometry is extracted from the UCERF3 database, which we then implement in a finite element mesh using Trelis 15. The structure of the earth’s crust is based on available tomographic data for the specific region. The Green’s functions are collected into the “heterogeneous” stiffness matrix Khet and used in RSQSim instead of the ones generated with Okada. Our sensitivity test is based on the comparison between RSQSim results dependent on the “heterogeneous” Khet and RSQSim results dependent on Khom (FE model with homogeneous material properties). Our preliminary simulations, although spatially centered in the San Jacinto fault zone, will provide significant insights in order to, first, quantify how much multiscale earthquake simulators are affected by material heterogeneities, and second, design future simulations based on FE methods and that will cover a larger domain.

Citation
Kyriakopoulos, C., Richards-Dinger, K. B., & Dieterich, J. H. (2016, 08). Exploring the sensitivity of multiscale seismic cycle simulations to material heterogeneities.. Poster Presentation at 2016 SCEC Annual Meeting.

Related Projects & Working Groups
Earthquake Simulators