List of Figures

The figures referenced in the document have been reduced in size to permit viewing on smaller screens.
The figures below are viewable and/or printable full size in GIF and PDF format.

Figure 1. Map showing attenuation boundary between WUS and CEUS. GIF, 13 kb; PDF, 284 kb

Figure 2. Mean hazard curves used in the June 1996 maps for selected cities (using June 1996 values). GIF, 21 kb; PDF, 201 kb

Figure 3. Scheme for producing hazard maps for the CEUS. GIF, 6 kb; PDF, 6 kb

Figure 4. M$$_max zones used in the CEUS (for models 1-4 only). Values are for moment magnitude. See text for description of magnitudes of large events used in model 5 for New Madrid and Charleston areas. GIF, 28 kb; PDF, 309 kb

Figure 5. a) Cumulative number of earthquakes versus time for the CEUS for magnitudes 3.0-3.5. Latitude and longitude ranges are shown to right. GIF, 6 kb; PDF, 80 kb b) Plot for area around New Madrid for same magnitude range. GIF, 5 kb; PDF, 18 kb

Figure 6. b-value plot for CEUS events (24.6-50 degrees N latitude; 65-105 degrees W longitude), excluding Charlevoix events. ML stands for fit from maximum likelihood method. LS denotes fit from least-squares method. b-values determined from each method are shown to right. GIF, 7 kb; PDF, 135 kb

Figure 7. Fictitious faults used to calculate hazard from large earthquakes in the New Madrid area (see text). Also shown are earthquakes from the Seeber and Armbruster (1992) catalog. GIF, 13 kb; PDF, 135 kb

Figure 8. Area source zone for New Madrid. GIF, 21 kb; PDF, 147 kb

Figure 9. Area source zone used for M7.3 events in the Charleston area. Seismicity is from Seeber and Armbruster (1992)catalog. GIF, 14 kb; PDF, 52 kb

Figure 10. Source zone used for the Eastern Tennessee area, based on the linear trend of the microseismicty (Martin Chapman, written comm., 1995). GIF, 9 kb; PDF, 60 kb

Figure 11. Background zones used for model 4 for the CEUS. GIF, 14 kb; PDF, 305 kb

Figure 12. Seismic hazard map (2% PE in 50 years) for CEUS made without background zone model. Weights are 0.5,0.25,0.25,0.,1.0 for models 1-5, respectively. GIF, 61 kb; PDF, 666 kb;

Figure 13. Seismic hazard map (PGA; 2% PE in 50 years) constructed from model 4 only (background zones in Figure 11). GIF, 43 kb; PDF, 446 kb

Figure 14. Seismic hazard map (PGA; 2% PE in 50 years) constructed from models 1-5 (including background zone). Weights are 0.4,0.2,0.2,0.2,1.0 for models 1-5, respectively. GIF, 62 kb; PDF, 649 kb

Figure 15. Mean hazard curves for selected CEUS cities, for cases without background zones (solid lines) and for cases with background zones (dashed lines). Symbols are keyed to cities. Weighting schemes are given in captions to Figures 14 and 15. GIF, 24 kb; PDF, 458 kb

Figure 16. Seismic hazard map (PGA; 2% PE in 50 years) constructed from adaptive weighting scheme using the historic seismicity, background zones, and model 5 (see text). GIF, 63 kb; PDF, 655 kb

Figure 17. Scheme used to make hazard calculations for WUS. GIF, 9 kb

Figure 18. Background zones used for model 2 for the WUS. GIF, 13 kb; PDF, 397 kb

Figure 19. Seismic hazard map constructed from model 1, not including faults (see left side of Figure 17) and without background zones. This map shows the ground motion values in only a limited portion of the WUS. GIF, 49 kb; PDF, 549 kb

Figure 20. Seismic hazard map made from only the background zones (model 2; see Figure 18). Note the lower values in northeastern California caused by the lower M$$_max values (see Figure 27 and text). This map shows the ground motion values in only a limited portion of the WUS. GIF, 42 kb; PDF, 343 kb

Figure 21. Seismic hazard map made from model 1 (gridded seismicity; weight 0.67) and model 2 (background zones, weight 0.33), not including faults. This map shows the ground motion values in only a limited portion of the WUS. GIF, 49 kb; PDF, 488 kb

Figure 22. Mean hazard curves for selected WUS cities, keyed by symbols. Solid lines are for case without background zones (gridded seismicity plus faults). Dashed lines are for case with background zones, (weight 0.33) gridded seismicity (weight 0.67), and faults. GIF, 95 kb; PDF, 393 kb

Figure 23. Seismic hazard map using adaptive weighting scheme (see text), not including faults. This map shows the ground motion values in only a limited portion of the WUS. GIF, 50 kb; PDF, 876 kb

Figure 24. Faults used in hazard maps. GIF, 14 kb; PDF, 393 kb

Figure 25. Faults used in hazard maps, California and Nevada region. GIF, 15 kb; PDF, 26 kb

Figure 26. Areal source zones used in WUS (see text). a-values in each zone were determined from shear rates. GIF, 10 kb; PDF, 11 kb

Figure 27. Outline of fault plane used for Cascadia subduction zone. Maximum depth of plane is 20 km. GIF, 9 kb; PDF, 9 kb

Figure A1. Shallow shear-wave velocity profiles used for CEUS: 1) site with 760 m/sec average shear-wave velocity for top 30m (B-C boundary; solid line) and 2) hard-rock site (dashed line). GIF, 7 kb; PDF, 11 kb