SCEC Award Number 12155 View PDF
Proposal Category Collaborative Proposal (Data Gathering and Products)
Proposal Title Continued Development of OpenSHA in Support of Operational Earthquake Forecasting, Hazard Assessment, and Loss Modeling
Investigator(s)
Name Organization
Thomas Jordan University of Southern California Edward Field United States Geological Survey Kevin Milner
Other Participants
SCEC Priorities 2b, 2e, 2a SCEC Groups WGCEP, CSEP, EFP
Report Due Date 03/15/2013 Date Report Submitted N/A
Project Abstract
 Major achievements were made in loss modeling integration with OpenSHA, including calculating expected annualized losses (EALs) for a proxy to the CEA residential catalog and every branch of the UCERF2 logic tree (Figure 1), showing the influence of each logic tree choice to the overall EAL. Interfaces with HAZUS were also improved allowing users to analyze OpenSHA generated hazard and scenario shakemaps with HAZUS. Visualization capabilities were also improved, including a new SCEC-VDO plugin framework and Earthquake Simulator result visualization tools. On the technical side, the UCERF3 inversion framework was finalized and optimized (1000x speedup over original algorithm), and interfaces with high performance computing resources were streamlined. The 2008 NSHMP results were also replicated in OpenSHA as a cross-validation exercise.
Intellectual Merit UCERF3 and other models implemented in OpenSHA have ended up posing some of our most profound and practically important scientific questions. For example, it has been shown that the elastic-rebound methodology used by WGCEP 2003 and 2007 is not self consistent, forcing us to consider the process more deeply. Another example is the implementation of spatiotemporal clustering, which seems to require elastic rebound to work properly (something that was not previously appreciated), and that sub-regions of the state need to more closely adhere to a Gutenberg-Richter distribution (otherwise one gets never-ending aftershock sequences). A final example is the difference between a multi-fault ruptures and a neighboring fault being quickly triggered as a separate event; we don’t presently know the answer.
Broader Impacts The UCERF2 loss calculations and tree trimming exercise is applicable to anyone wanting to use UCERF2, especially loss modeling organizations. OpenSHA is a tool used by the community, and various improvements and bugfixes were in direct response to user reported issues/suggestions. The UCERF3 inversion framework developed will serve as the basis for the UCERF3 hazard model which, upon release, will be high impact and used for 2014 National Seismic Hazard Maps and future building codes.
Exemplary Figure Figure 1
Tornado diagram from Porter et al 2012, Figure 7, showing effect of each UCERF2 logic tree branch on expected annualized loss (EAL) for a proxy to the CEA residential catalog.