Seismic-Hazard Maps for the Conterminous United States, 2008

Scientific Investigations Map 3195
Prepared in cooperation with the California Geological Survey
By: , and 



Probabilistic seismic-hazard maps were prepared for the conterminous United States portraying peak horizontal acceleration and horizontal spectral response acceleration for 0.2- and 1.0-second periods with probabilities of exceedance of 10 percent in 50 years and 2 percent in 50 years. All of the maps were prepared by combining the hazard derived from spatially smoothed historic seismicity with the hazard from fault-specific sources. The acceleration values contoured are the random horizontal component. The reference site condition is firm rock, defined as having an average shear-wave velocity of 760 m/s in the top 30 meters corresponding to the boundary between NEHRP (National Earthquake Hazards Reduction program) site classes B and C. This data set represents the results of calculations of hazard curves for a grid of points with a spacing of 0.05 degrees in latitude and longitude. The grid of points were contoured to produce the final representation of the seismic-hazard. These maps are intended to summarize the available quantitative information about seismic ground motion hazard for the conterminous United States from geologic and geophysical source.

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Seismic-Hazard Maps for the Conterminous United States, 2008
Series title Scientific Investigations Map
Series number 3195
DOI 10.3133/sim3195
Year Published 2011
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) National Earthquake Hazards Reduction Program
Description Sheets 1-6: 31 inches x 24 inches, Map PDF, GIS data zip; Metadata; Geologic map database
Country United States
Projection Albers eaul-area conic
Scale 7000000
Additional Online Files (Y/N) Y
Google Analytic Metrics Metrics page
Additional publication details