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Map Layer Info

Seismic Hazard Map for the United States

What this map layer shows:

Areas of equal seismic hazard, and indicates the minimum peak horizontal ground acceleration value for each area.
opens the U.S. Geological Survey home page
Background Information
Sample map Sample Map
Earthquakes can affect the normal activities of people through ground motion, such as surface faulting, ground shaking, landslides, liquefaction, or tectonic deformation, or through tsunamis and seiches. The potential for these effects is known as seismic hazard. This map represents a model showing the probability that ground motion will reach a certain level during an earthquake. The data show peak horizontal ground acceleration (the fastest measured change in speed, for a particle at ground level that is moving horizontally because of an earthquake) with a 10 percent probability of exceedance in 50 years. This map was compiled by the U.S. Geological Survey (USGS) Geologic Hazards Team, which conducts global investigations of earthquake, geomagnetic, and landslide hazards. These scientists study the physical and mechanical properties of the Earth's crust and structure to aid in understanding earthquakes, and they work to educate the public and the scientific community to lessen the human impact of future earthquakes.

The Seismic Hazard Map for the United States shows areas of equal seismic hazard and indicates the minimum peak horizontal ground acceleration value for each area. Further information on earthquakes is available from the USGS Earthquake Hazards Program page, and information on earthquake terms is available from the Earthquake Image Glossary. Additional map images can be found on the National Seismic Hazard Mapping Project page.


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Seismic Hazard
Geologic Hazards

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Seismic Hazard