Project Abstract
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Viscoelastic deformation following large earthquakes in Southern California has been studied pervasive-ly (e.g., Pollitz et al., 2003; Freed et al., 2007) providing estimates of lower crustal and upper mantle rheology from these time-dependent data. As a complement to these studies, nominally steady inter-seismic GPS data have been interpreted with both tectonic and earthquake cycle models to similarly provide estimates of lower crustal and upper mantle rheology (e.g., Meade and Hager, 2005, Smith and Sandwell, 2009; Pollitz et al., 2008; Chuang and Johnson, 2011; Hearn et al., 2013). However the links between post- and interseismic deformation have been less thoroughly examined in the context of high-fidelity representations of fault system geometry in southern California (Plesch et al., 2007). Here we propose to apply the that can simultaneously explain rapid postseismic deformation following the 1992 Landers and 1999 Hector Mine earthquakes as well as the longer-term GPS velocity fields developed as the SCEC Crustal Motion Model. Our plan was to utilize a block model geometry based on the Rectilin-ear Community Fault Model and integrating the polyviscous viscoelastic code described by in our proposal from last year. The work for this coming year is focused not only code development but rather on the application of viscoelastic block models with multiple relaxation time scales to high-fidelity represen-tations of the southern California fault system. However, upon starting these calculations we determined that the required CPU time for a complete southern California model would be ~2 million core hours per run, so we pivoted, successfully! |
