Nico Luco
Arthur D. Frankel
Mark D. Petersen
Brad T. Aagaard
Annemarie S. Baltay Sundstrom
Michael L. 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
Morgan P. Moschetti
2018
<div><p>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.,<span> </span><span class="inline-formula no-formula-id"><span id="MathJax-Element-1-Frame" class="MathJax" data-mathml="<math xmlns="http://www.w3.org/1998/Math/MathML"><mi xmlns="" mathvariant="bold">M</mi></math>"><span id="MathJax-Span-1" class="math"><span><span id="MathJax-Span-2" class="mrow"><span id="MathJax-Span-3" class="mi">M</span></span></span></span><span class="MJX_Assistive_MathML">M</span></span></span> 6.7 Northridge, California,<span> </span><a class="link link-ref link-reveal xref-bibr" data-open="rf14">Gao<span> </span><i>et al.</i>, 1996</a>;<span> </span><span class="inline-formula no-formula-id"><span id="MathJax-Element-2-Frame" class="MathJax" data-mathml="<math xmlns="http://www.w3.org/1998/Math/MathML"><mi xmlns="" mathvariant="bold">M</mi></math>"><span id="MathJax-Span-4" class="math"><span><span id="MathJax-Span-5" class="mrow"><span id="MathJax-Span-6" class="mi">M</span></span></span></span><span class="MJX_Assistive_MathML">M</span></span></span> 6.9 Kobe, Japan,<span> </span><a class="link link-ref link-reveal xref-bibr" data-open="rf18">Kawase, 1996</a>;<span> </span><span class="inline-formula no-formula-id"><span id="MathJax-Element-3-Frame" class="MathJax" data-mathml="<math xmlns="http://www.w3.org/1998/Math/MathML"><mi xmlns="" mathvariant="bold">M</mi></math>"><span id="MathJax-Span-7" class="math"><span><span id="MathJax-Span-8" class="mrow"><span id="MathJax-Span-9" class="mi">M</span></span></span></span><span class="MJX_Assistive_MathML">M</span></span></span> 6.8 Nisqually, Washington,<span> </span><a class="link link-ref link-reveal xref-bibr" data-open="rf9">Frankel, Carver, and Williams, 2002</a>). 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.,<span> </span><a class="link link-ref link-reveal xref-bibr" data-open="rf27">Wong<span> </span><i>et al.</i>, 2002</a>;<span> </span><a class="link link-ref link-reveal xref-bibr" data-open="rf6">Cramer<span> </span><i>et al.</i>, 2006</a>;<span> </span><a class="link link-ref link-reveal xref-bibr" data-open="rf13">Frankel<span> </span><i>et al.</i>, 2007</a>;<span> </span><a class="link link-ref link-reveal xref-bibr" data-open="rf15">Graves<span> </span><i>et al.</i>, 2011</a>). 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.</p></div><div><p>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.</p></div>
application/pdf
10.1785/0220170261
en
Seismological Society of America
Integrate urban‐scale seismic hazard analyses with the U.S. National Seismic Hazard Model
article