SCEC Award Number 14141 View PDF
Proposal Category Individual Proposal (Data Gathering and Products)
Proposal Title Enhancements to the SCEC Unified Structural Representation: CFM, SCFM, & CVMH
Investigator(s)
Name Organization
John Shaw Harvard University
Other Participants Andreas Plesch
SCEC Priorities 4a, 4c, 6a SCEC Groups USR, GMP, Seismology
Report Due Date 03/15/2015 Date Report Submitted N/A
Project Abstract
 We completed a series of enhancements to the Community Fault (CFM) and Velocity (CVMH) models, which together comprise the SCEC Unified Structural Representation (USR). These improvements were intended to facilitate use of the community models in a wide range of SCEC science and hazard assessment efforts.

In addition, we were asked within the grant period by SCEC to co-lead a SCEC-ERI Summer School for Earthquake Science on the topic of “Wave and Rupture Propagation with Realistic Velocity Structures.” The four day program involved activity sessions where participants used SCEC Community Modeling Environment (CME) tools to access the CFM and CVMH. Information gathered from these models was used, in turn, used to support ground motion calculations.

Project results in 2014 include:
1) Release of two new versions of the SCEC CFM: 4.0 as a fully vetted version evaluated by an SCEC working group and 5.0 incorporating the latest model improvements.
2) Initiation of the review process for the northern California fault representations (Statewide CFM version 3.0);
3) Develop and distribute a new set of regularly gridded CFM representations at resolutions that are targeted by SCEC investigators for fault system modeling;
4) Completion and publication of a comprehensive article on the SCEC Unified Structural Representation (USR) framework, co-authored by 17 SCEC investigators.
5) Development of an instructional tutorials on the CFM and CVM using SCEC’s VDO and UCVM software, in conjunction with the SCEC CME group.
6) Co-leadership of the 2014 SCEC-ERI workshop in Oxnard, CA (9/28-10/2).
Intellectual Merit This grant represents the primary effort to support and develop the SCEC Community Fault and Velocity models (CFM, SCFM, and CVMH). A series of improvements to these models will help facilitate their use in probabilistic seismic hazards assessments, fault system modeling, tectonic studies, and earthquake simulators. These efforts directly address SCEC priorities 4 “Structure and evolution of fault zones and systems: relation to earthquake physics” and 6 “Seismic wave generation and scattering: prediction of strong ground motions.”
Broader Impacts This work directly addresses SCEC’s primary mission to improve seismic hazards assessment in southern California by defining the 3D geometry and interaction of active fault systems. In addition, the project has enhanced the description of 3D velocity structure in the SCEC Community Velocity Model, with the goal of improving the accuracy of earthquake wave propagation studies and strong ground motion predictions. Support of the SCEC-ERI Summer School also helped to train students and scientists in the use of these resources, and promoted international cooperation in the field of earthquake hazards assessment.
Exemplary Figure Figure 2: Perspective view of the San Jacinto fault system in CFM 5.0. The San Jacinto and many other fault representations in the model have been made more compatible with detailed surface traces from the USGS Quaternary Fault & Fold Database (red traces) and relocated seismicity (blue) (Lin et al., 2007; Yang et al., 2012; Hauksson et al., 2012). As a result, these fault representations are more precise and – as shown here for the San Jacinto fault – are more highly segmented.