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Integrate urban‐scale seismic hazard analyses with the U.S. National Seismic Hazard Model

March 1, 2018

For more than 20 yrs, damage patterns and instrumental recordings have highlighted the influence of the local 3D geologic structure on earthquake ground motions (e.g., M">MM 6.7 Northridge, California, Gao et al., 1996; M">MM 6.9 Kobe, Japan, Kawase, 1996; M">MM 6.8 Nisqually, Washington, Frankel, Carver, and Williams, 2002). Although this and other local‐scale features are critical to improving seismic hazard forecasts, historically they have not been explicitly incorporated into the U.S. National Seismic Hazard Model (NSHM, national model and maps), primarily because the necessary basin maps and methodologies were not available at the national scale. Instead, the U.S. Geological Survey (USGS), its partners, and external groups developed urban seismic hazard maps (urban models and maps) that consider detailed site effects in local areas (e.g., Wong et al., 2002Cramer et al., 2006Frankel et al., 2007Graves et al., 2011). The disconnect between the urban and national hazard models, however, means that the national models, which underlie U.S. building codes and other applications, do not make use of all of the scientific results informing earthquake ground‐shaking hazards.

We recommend that future U.S. national seismic hazard assessment make use of all available regional information, including that in urban models. In this column, we describe the roles of and differences between the urban and national models, and discuss the obstacles to and benefits of integrating the urban models with the national model. Future progress on this issue will require further coordination and implementation efforts between the USGS and external partners.

Publication Year 2018
Title Integrate urban‐scale seismic hazard analyses with the U.S. National Seismic Hazard Model
DOI 10.1785/0220170261
Authors Morgan P. Moschetti, Nicolas Luco, Arthur Frankel, Mark D. Petersen, Brad T. Aagaard, Annemarie S. Baltay, Michael Blanpied, Oliver S. Boyd, Richard W. Briggs, Ryan D. Gold, Robert Graves, Stephen H. Hartzell, Sanaz Rezaeian, William J. Stephenson, David J. Wald, Robert A. Williams, Kyle Withers
Publication Type Article
Publication Subtype Journal Article
Series Title Seismological Research Letters
Index ID 70196334
Record Source USGS Publications Warehouse
USGS Organization Geologic Hazards Science Center