Highlight 6--
Seismic Hazard Maps Help Save Lives and Property
The latest revision of GD national probabilistic shaking-hazard maps (fig. 6), released in 1996, integrates information about the rate at which earthquakes occur in different areas and the distance that strong shaking extends from earthquake sources. Colors show the levels of horizontal shaking (as a percentage of the Earth's gravitational force) that have a 10 percent chance of being exceeded in a 50-year period. Maps such as this have been used by engineers to help update seismic risk maps and to establish building code provisions. More than 20,000 cities, counties, and local government agencies use these codes to help determine the construction requirements necessary to preserve public health and safety in earthquakes. A separate, more detailed seismic hazard map for California was developed cooperatively with the California Division of Mines and Geology (Frankel and others, 1997).
Figure 6. National probabilistic shaking-hazard map. Shaking is expressed as a percentage of g, where g is the acceleration of a falling object due to gravity. From Brown and others (1996).
<----- Back to Goal 1
This page is <https://pubs.usgs.gov/circular/c1172/h6.html>
Maintained by L. McElroy
Last updated 04.08.98