SCEC Award Number 18035 View PDF
Proposal Category Collaborative Proposal (Data Gathering and Products)
Proposal Title Implementing rapid, probabilistic association of earthquakes with source faults in the CFM for southern California
Name Organization
John Shaw Harvard University Egill Hauksson California Institute of Technology
Other Participants Andreas Plesch, Senior Research Scientist
Men-Andrin Meier, Postdoc
SCEC Priorities 3a, 2a, 3e SCEC Groups Seismology, EFP, CXM
Report Due Date 03/15/2019 Date Report Submitted 02/12/2019
Project Abstract
This project has developed a new, statistically robust way to identify the fault (or sets of candidate faults) in the Community Fault Model (CFM) that generated an earthquake using information typically provided soon after these events occur (Evans, 2016; Evans et al., 2019). During 2018, we have made progress on implementation of the earthquake association to a CFM fault (Eq2CFM) method through the SCEDC, and developed a series of enhancements to the data products that are provided (common fault name associations, fault maps, links to fault attributes [e.g., though USGS Qfault database]). The SCEDC will host this catalog locally and plans to submit this new catalog attribute to the ANSS ComCat national catalog. The SCEDC will also submit this product near-real time via email and post it to websites and NEIC to make it part of their web pages and part of the ANSS ComCat.
Intellectual Merit This project relates to many key SCEC objectives and will improve our understanding of earthquake activity across southern California. Specifically, objective earthquake-to-fault associations are of value in providing an important measure of the activity of faults within the southern California plate boundary, as well as objectively assessing the completeness of the SCEC fault models. Moreover, as the method is implemented in near real-time, it will prove helpful in identifying clusters of small earthquakes that may be foreshocks of larger events on a major fault, which may be of value in regional hazards assessment.
Broader Impacts The earthquake-to-fault associations will assist in communicating objective information about the faults that source earthquakes to the scientific community and general public. Ultimately, more accurate identification of source faults for large earthquakes may help responders know which planned scenario is most like the situation they are facing. Such guidance should lead to more effective responses.
Exemplary Figure Figure 3: Primary association of the M>=3 catalog using the historical statistical model. Over 60% of events are associated. Colors refer to an internal fault ID for both events and fault representations.