Hazards

The USGS is currently preparing updated seismic hazard maps for the conterminous U.S. These maps will be released and available for access at this site once the maps have received USGS Director's Approval. This approval is expected during the fall of 2014.

Seismic Hazard Maps and Data

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Probabilistic and scenario ground-motion hazard maps, input and output data, and documentation. More…

  • Lower 48
    Ground-motion hazard maps originally created in 1996 and updated in 2002 and 2008.
  • Alaska
    Ground-motion hazard maps originally created in 1999 and updated in 2007.
  • Hawaii
    Ground-motion hazard map (1998).
  • Puerto Rico & U.S. Virgin Islands
    Ground motion hazard map (2003).
  • Guam & Marianas
    Seismic Hazard Assessment for Guam and the Northern Mariana Islands.
  • Samoa & Pacific Islands
    Seismic Hazard Assessment for Samoa/Pacific Islands.
  • Urban & Regional
    Probabilistic and deterministic hazard maps for urban areas using local geologic site effects.
  • Scenarios
    Expected ground motions and effects of specific hypothetical large earthquakes using Shakemap.
  • Time-Dependent
    Ground-motion hazard maps assuming faults are less likely to rupture after recent large events.
  • Foreign
    Probabilistic and deterministic ground motion hazard maps for SE Asia, Afghanistan, and Gujarat (India).

Seismic Design Maps, Data, and Tools for Engineers

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Ground motion parameter values for building and bridge design. More…

Seismic Hazard Analysis Tools

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Create customized hazard and probability maps with additional options to assess individual source-contributions to overall hazard. More…

  • Create Custom Hazard Maps
    Replot local portions of national hazard maps. You define center and span.
  • Interactive Hazard Maps
    On-line SA or PGA maps for 2% or 10% in 50 year PE for conterminous US with features you can turn on and off. Zoom in or pan out.
  • Earthquake Probability
    Map and table of probability that an earthquake with magnitude > M and distance < R will occur in the next k years. Uses the 2009 or 2002 model. Centered on user-supplied location.
  • Hazard Curve Application
    Displays hazard curves and uniform hazard response spectra, and provides details on programmatic access to USGS hazard data.
  • Interactive Deaggregations
    Tables and plots of source contributions to hazard exceedance by magnitude, distance, ε and ε0 in the conterminous US, Alaska, and Hawaii.
  • Vs30
    Generates map and grid of Vs30 derived from topographic slope for anywhere in the world.
  • Banded Deaggregation
    For a given location, generates a plot of ground motion in bands versus rate as well as an ascii text file of the hazard matrices for each ground motion band.

About the NSHM Project

Learn who we are, and what we do. Gain a better understanding of what these maps and data mean. Information for beginners and experts alike. More…

Quaternary Faults

Where are the faults in my area, and when did they last have a large earthquake? Find maps and comprehensive geologically based information on known or suspected active faults and folds in the United States. More…