SCEC Award Number 24111 View PDF
Proposal Category Individual Research Project (Single Investigator / Institution)
Proposal Title Statewide earthquake simulators: Exploring fault system geometry uncertainties and impacts on behavior and hazard
Investigator(s)
Name Organization
Bruce Shaw Columbia University
SCEC Milestones C1,2,3-1, D1-1, D3-2, D3-3 SCEC Groups FARM, GM, EFP
Report Due Date 03/15/2025 Date Report Submitted 04/04/2025
Project Abstract
 Earthquake simulators have the potential to contribute to our understanding of earthquake hazard in a number of different ways. One way is in directly estimating earthquake rupture forecasts, which, when combined with ground motion models, give hazard estimates which compare very well with traditional statistical model estimates [Shaw, et al, 2018]. A second way is to use the models to help develop and constrain assumptions in the statistical models underlying National Seismic Hazard Models. Using the simulators to improve rupture plausibility filters is an example of this [Milner, Shaw, and Field, 2022]. Using simulators to improve scaling relations is another [Shaw, 2023]. Using simulators to develop segmentation constraints is yet another [Shaw and Dieterich, 2007; Field et al and Shaw, 2024]. These results have been incorporated into the new USGS National Seismic Hazard Model [Field et al and Shaw, 2024; Petersen et al and Shaw, 2024], and the new GNS New Zealand National Seismic Hazard Model [Gerstenberger et al and Shaw, 2024].
A third way is to use the simulators as source models for ground motion studies [Milner, Shaw, et al, 2021; Shaw, Milner, and Goulet, 2025]. All three approaches have shown much promise. This body of work aims to use earthquake simulators to improve our understanding of earthquake physics, and earthquake hazard through a variety of ways.
Intellectual Merit Earthquake physics remains uncertain, but we also have candidate models that we can explore and look for behaviors that emerge, and their potential genericness and sensitivities to details we know we don't know. Earthquake simulators enable us to study emergent behaviors, their sensitivities to a range of features, and their implications for hazard. They provide a setting where algorithms and hypotheses can be further developed.
Broader Impacts This work contributed to improving earthquake hazard estimates. Improving earthquake hazard improves our ability to design, plan for, and mitigate the impacts on society, saving lives and property.
Project Participants Bruce Shaw. Also collaborated with a large group at the USGS, and GNS New Zealand.
Exemplary Figure Figure 2: Aided USGS NSHM 2023 in multiple ways. This figure illustrates three ways the PI’s research contributed to the hazard estimates. One is by developing improved rules for rupture sets used in hazard inversions, which (a) and (b) illustrate from [Milner, Shaw, and Field,, 2022].. A second is from the scaling relations (Shaw, 2023), which (c) also illustrates. A third is from the segmentation formulation, which (c) illustrates From [Field et al and Shaw, 2023]
Linked Publications

Add missing publication or edit citation shown. Enter the SCEC project ID to link publication.