SCFM 3.1: Updates, maps and modeling support

Andreas Plesch, John H. Shaw, . SCFM Working Group, & Craig Nicholson

Published August 15, 2018, SCEC Contribution #8725, 2018 SCEC Annual Meeting Poster #144

We present an updated and enhanced version of the northern California Statewide Community Fault Model (SCFM-V.3.1). The updated model includes improved 3d fault representations, a new GIS trace map fully consistent with the 3d model, and a set of triangular meshes of fault surfaces more suitable for numerical modeling applications.

Based on generous feedback resulting from an earlier workshop on evaluating and ranking the SCFM, we could improve on a series of fault models focused on the offshore Hosgri-San Simeon fault zone, the offshore San Gregorio fault zone and parts of the San Andreas fault zone. Notable additions include the offshore eastern Monterey Bay and Gualala faults, both tens of kilometers in length and in close proximity to the coast.

To allow for convenient map access to the 3D model, we extracted the fault surface traces and blind fault tip-lines from the 3d fault representations and made those available in GIS compatible formats. The expected use allows for layering these maps on existing maps for evaluation and comparison purposes, as for example to assess the degree of model generalizations for a given fault, or its proximity to a large urban population.

The native tsurf 3d representations of the fault geometry are based on the availability and resolution of the data used to evaluate and eventually construct a given triangular mesh. Therefore, the native meshes reflect these conditions and are often not directly suitable for numerical modeling applications which have conflicting requirements on the properties of a triangular mesh. It is possible to retriangulate with high fidelity the native tsurf representations using various methods. Thus, in addition to the native 3D fault models and in an effort to support efforts seeking to utilize the SCFM in a variety of numerical modeling environments, we also provide a set of remeshed 3D fault surfaces with higher quality, regular-gridded triangular elements of ~1-km dimension. In further modeling support, we demonstrate use of Extensible Markup Language (XML) to encode fault geometry and fault meta-data into the general purpose, ISO-defined, 3d graphics format X3D.

Key Words
Fault modeling, CFM, statewide, tectonics, CXM, USR

Citation
Plesch, A., Shaw, J. H., SCFM Working Group, .., & Nicholson, C. (2018, 08). SCFM 3.1: Updates, maps and modeling support. Poster Presentation at 2018 SCEC Annual Meeting.

Related Projects & Working Groups
SCEC Community Models (CXM)