2008:2002 Figure Ratios

The figues available for download on this page are ratios between the probabilitic ground motions of the 2008 NSHMP update (numerator) and the 2002 NSHMP update (denominator). Vs30 is 760 m/s in all cases. These figures do not reflect actual ground motion values corresponding to the 2008 update, but rather contain ratios between the ground motion values computed for the 2008 update as compared to ground motion values for the 2002 update. High values on these maps to not necessarily indicate high ground motion values, but simply an increase in ground motion values from the 2002 update. Similarly, small values on these maps to not necessarily indicate small ground motion values, but simply a decrease in ground motion values from the 2002 update. You can view static ground motion maps for the 2008 update for figures displaying actual ground motion values corresponding to the 2008 update. Alternatively, all figures (ground motion maps as well as ratio maps) are available for download in this zip file(11Mb).

Click a column header to sort by values in that column. Shift+Click to sort by multiple columns.
Region Name Return Period Spectral Acceleration Download
Western U.S. 2% in 50 Years 0.5Hz (2.0 Seconds) [JPG | PS]
Western U.S. 2% in 50 Years 5Hz (0.2 Seconds) [JPG | PS]
Western U.S. 2% in 50 Years 1Hz (1.0 Second) [JPG | PS]
Western U.S. 2% in 50 Years 2Hz (0.5 Seconds) [JPG | PS]
California-Nevada 2% in 50 Years 1Hz (1.0 Second) [JPG | PS]
California-Nevada 2% in 50 Years 5Hz (0.2 Seconds) [JPG | PS]
New Mexico 2% in 50 Years 5Hz (0.2 Seconds) [JPG | PS]
Central/Eastern U.S. 2% in 50 Years 1Hz (1.0 Second) [JPG | PS]
Central/Eastern U.S. 10% in 50 Years 1Hz (1.0 Second) [JPG | PS]
Central/Eastern U.S. 10% in 50 Years 5Hz (0.2 Seconds) [JPG | PS]
Central/Eastern U.S. 2% in 50 Years 5Hz (0.2 Seconds) [JPG | PS]
Central/Eastern U.S. 2% in 50 Years Peak Ground Acceleration [JPG | PS]
New Madrid Seismic Zone 2% in 50 Years 1Hz (1.0 Second) [JPG | PS]
New Madrid Seismic Zone 10% in 50 Years 5Hz (0.2 Seconds) [JPG | PS]
New Madrid Seismic Zone 2% in 50 Years Peak Ground Acceleration [JPG | PS]
New Madrid Seismic Zone 2% in 50 Years 5Hz (0.2 Seconds) [JPG | PS]
South Carolina 2% in 50 Years 5Hz (0.2 Seconds) [JPG | PS]
South Carolina 2% in 50 Years 1Hz (1.0 Second) [JPG | PS]