Earthquake scenario development in the 2023 USGS NSHM update

Earthquake scenarios are generally selected to serve a wide variety of local and regional needs ranging from testing a community’s ability to respond to earthquakes to developing proactive targeted mitigation strategies for minimizing impending risk. These deterministic scenarios can also be used to communicate seismic hazard and risk to audiences who are not well versed in more complex methods like probabilistic seismic hazard assessment (PSHA). Accordingly, the U.S. Geological Survey plans to produce a suite of scenarios to accompany the release of the 2023 update to the National Seismic Hazard Model (NSHM). The manuscript describes a preliminary framework for scenario development from hazard and risk/consequence perspectives. Historical seismicity-, hazard-, and consequence-based scenario selection techniques as well as other factors in scenario selection are discussed. The 2023 NSHM scenario development efforts aim to incorporate both hazard and risk considerations while working in close collaboration with local experts and stakeholders.