The 2014 United States National Seismic Hazard Model

Abstract

New seismic hazard maps have been developed for the conterminous United States using the latest data, models, and methods available for assessing earthquake hazard. The hazard models incorporate new information on earthquake rupture behavior observed in recent earthquakes; fault studies that use both geologic and geodetic strain rate data; earthquake catalogs through 2012 that include new assessments of locations and magnitudes; earthquake adaptive smoothing models that more fully account for the spatial clustering of earthquakes; and 22 ground motion models, some of which consider more than double the shaking data applied previously. Alternative input models account for larger earthquakes, more complicated ruptures, and more varied ground shaking estimates than assumed in earlier models. The ground motions, for levels applied in building codes, differ from the previous version by less than ±10% over 60% of the country, but can differ by ±50% in localized areas. The models are incorporated in insurance rates, risk assessments, and as input into the U.S. building code provisions for earthquake ground shaking.

A Machine Learning Approach to Developing Ground Motion Models From Simulated Ground Motions

“…Figure also plots the standard deviations of the residuals of the predicted ground motions subtracted from the target ground motions (in log space) compared with leading GMMs (as used in Petersen et al (): Boore et al (); Abrahamson et al (); Campbell and Bozorgnia (); and Chiou and Youngs (), abbreviated as BSSA, ASK, CB, and CY, respectively, throughout the rest of this article) as a function of period (the median residuals are within 0.01 logarithm units of 0 here, so we omit plotting them). Since the empirical and synthetic models are derived from different data sets, the GMMs' residual values are shown simply for comparison.…”

A new paradigm for large earthquakes in stable continental plate interiors

“…Because SCR earthquakes are infrequent, occur in regions where present‐day strain rates are very low, and rupture faults that are difficult to identify geologically, quantifying the associated hazard is a challenge [ Ellsworth et al , ; Petersen et al , ]. Yet accurate hazard estimates in SCRs are important for engineering design, in particular, in the “post‐Fukushima” era [ Joskow and Parsons , ] for nuclear infrastructure that are designed for safety on a 10,000 year timescale.…”

What can strike‐slip fault spacing tell us about the plate boundary of western North America?

“…Furthermore, estimates of fault characteristics can improve physicsbased models of the earthquake cycle and hazards (e.g. Console, Carluccio, Papadimitriou, & Karakostas, 2015;Pagani et al, 2014;Petersen et al, 2015).…”