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Preliminary 2018 national seismic hazard model for the conterminous United States

December 31, 2018

The 2014 U.S. Geological Survey national seismic hazard model for the conterminous U.S. will be updated in 2018 and 2020 to coincide with the Building Seismic Safety Council’s Project 17 timeline for development of new building code design criteria. The two closely timed updates are planned to allow more time for the Provisions Update Committee to analyze the consequences of the hazard model changes in the design criteria. To prepare the 2018 update we held a workshop (March 7-8, 2018) with scientists and engineers to solicit feedback on the model. The 2018 model will be available for public comment during the summer of 2018. The purpose of this paper is to solicit feedback on the modeling choices and results. The 2018 NSHM considers an updated seismicity catalog and certain key changes in the way ground motions are calculated. First, we implemented new Next Generation Attenuation Relationships for the Central and Eastern North America Region and other published models that allow for the calculation of ground motions at additional periods and site classes in the central and eastern U.S. (CEUS). Second, basin depth terms were implemented in the ground motion models in select regions of the western U.S. (WUS) to account for enhanced long-period ground motions at softer soil sites overlying sedimentary basins. Preliminary results indicate higher ground motions for all periods in parts of the CEUS and for long-periods and soft soils in urban areas overlying sedimentary basins in the WUS.

Publication Year 2018
Title Preliminary 2018 national seismic hazard model for the conterminous United States
Authors Mark D. Petersen, Allison Shumway, Peter M. Powers, Charles Mueller, Sanaz Rezaeian, Morgan P. Moschetti, Daniel E. McNamara, Eric M. Thompson, Oliver S. Boyd, Nicolas Luco, Susan M. Hoover, Kenneth S. Rukstales
Publication Type Conference Paper
Publication Subtype Conference Paper
Index ID 70197879
Record Source USGS Publications Warehouse
USGS Organization Earthquake Science Center; Geologic Hazards Science Center