This hazard map is a simplified 2% in 50-year probability of exceedance map for fixed VS30 760 m/s.
What is seismic hazard? What is a seismic hazard map? How are they made? How are they used? Why are there different maps, and which one should I use?
Seismic hazard is the hazard associated with potential earthquakes in a particular area, and a seismic hazard map shows the relative hazards in different areas. The maps are made by considering what we currently know about:
- Past faults and earthquakes
- The behavior of seismic waves as they travel through different parts of the U.S. crust
- The near-surface site conditions at specific locations of interest
Hazard maps can be used for land-use planning, mitigation, and emergency response.
The different maps show different probabilities that are selected to provide an idea of the relative range of hazard across the US. The larger probabilities indicate the level of ground motion likely to cause problems in the western US. The smaller probabilities show how unlikely damaging ground motions are in many places of the eastern US. However, basically the values chosen reflect the more recent history in earthquake engineering.
How does an individual person select a map? Technical users probably have to follow predefined rules. A non-technical person may be interested in avoiding living in a location where significant shaking will cause worry, deciding on whether to carry earthquake insurance, or deciding whether to do some rehabilitation for an existing dwelling. The probability level chosen should reflect how anxious one is to avoid earthquake shaking.
Learn more:
- Earthquake Hazards 101: The Basics provides more details on all of these questions.
- Unified Hazard Tool - For advanced users: earthquake hazard and probability maps, hazard curves, and deaggregation
Related
What is a seismic zone, or seismic hazard zone?
What are the earthquake hazards/risks where I live?
How will my house hold up in an earthquake? Can the USGS send someone out to evaluate my property?
How do I decide whether or not to get earthquake insurance?
How do earthquakes affect buildings?
What is the likelihood of a large earthquake at location X? Is it safe to go to X since they've been having a lot of earthquakes lately?
What is the probability that an earthquake is a foreshock to a larger earthquake?
What is the probability that an earthquake will occur in the Los Angeles Area? In the San Francisco Bay area?
What is the difference between earthquake early warning, earthquake forecasts, earthquake probabilities, and earthquake prediction?
Can the National Seismic Hazard Maps be used as an earthquake forecast tool for the near future?
How do I get earthquake hazard maps for locations outside of the U.S.?
How are engineers working to make roads and buildings safer?

This hazard map is a simplified 2% in 50-year probability of exceedance map for fixed VS30 760 m/s.

Fault sections being used in the creation of the 2023 U.S. Seismic Hazard Maps. Blue lines are normal faults, yellow lines are reverse faults, and red lines are strike-slip faults.
Fault sections being used in the creation of the 2023 U.S. Seismic Hazard Maps. Blue lines are normal faults, yellow lines are reverse faults, and red lines are strike-slip faults.
HayWIred scenario earthquake map.
HayWIred scenario earthquake map.

Warren Hall on California State University East Bay's Hayward campus is scheduled to be demolished Aug. 17, 2013 for seismic safety reasons. The landmark building's implosion will produce energy similar to a small earthquake that can be used to study and map the nearby Hayward Fault. In partnership with the university, U.S.
Warren Hall on California State University East Bay's Hayward campus is scheduled to be demolished Aug. 17, 2013 for seismic safety reasons. The landmark building's implosion will produce energy similar to a small earthquake that can be used to study and map the nearby Hayward Fault. In partnership with the university, U.S.
Oblique aerial view of San Andreas Fault (between white arrows) in southeastern Coachella Valley, near Red Canyon; view to the west.
Oblique aerial view of San Andreas Fault (between white arrows) in southeastern Coachella Valley, near Red Canyon; view to the west.

Seismic hazard across the State of Hawaii, with high seismic hazards depicted with warm colors (red-orange) and relatively low seismic hazards depicted with cool colors (green). Engineers use these types of maps to prescribe building codes known as Seismic Design Codes (SDC) and create earthquake resistant structures.
Seismic hazard across the State of Hawaii, with high seismic hazards depicted with warm colors (red-orange) and relatively low seismic hazards depicted with cool colors (green). Engineers use these types of maps to prescribe building codes known as Seismic Design Codes (SDC) and create earthquake resistant structures.
National earthquake information center strategic plan, 2019–23
The HayWired Earthquake Scenario
Updating the USGS seismic hazard maps for Alaska
United States Geological Survey (USGS) Natural Hazards Response
Earthquake hazards: A national threat
The USGS Earthquake Hazards Program - investing in a safer future
ANSS-Advanced National Seismic System
USGS National Seismic Hazard Maps
Related
What is a seismic zone, or seismic hazard zone?
What are the earthquake hazards/risks where I live?
How will my house hold up in an earthquake? Can the USGS send someone out to evaluate my property?
How do I decide whether or not to get earthquake insurance?
How do earthquakes affect buildings?
What is the likelihood of a large earthquake at location X? Is it safe to go to X since they've been having a lot of earthquakes lately?
What is the probability that an earthquake is a foreshock to a larger earthquake?
What is the probability that an earthquake will occur in the Los Angeles Area? In the San Francisco Bay area?
What is the difference between earthquake early warning, earthquake forecasts, earthquake probabilities, and earthquake prediction?
Can the National Seismic Hazard Maps be used as an earthquake forecast tool for the near future?
How do I get earthquake hazard maps for locations outside of the U.S.?
How are engineers working to make roads and buildings safer?

This hazard map is a simplified 2% in 50-year probability of exceedance map for fixed VS30 760 m/s.
This hazard map is a simplified 2% in 50-year probability of exceedance map for fixed VS30 760 m/s.

Fault sections being used in the creation of the 2023 U.S. Seismic Hazard Maps. Blue lines are normal faults, yellow lines are reverse faults, and red lines are strike-slip faults.
Fault sections being used in the creation of the 2023 U.S. Seismic Hazard Maps. Blue lines are normal faults, yellow lines are reverse faults, and red lines are strike-slip faults.
HayWIred scenario earthquake map.
HayWIred scenario earthquake map.

Warren Hall on California State University East Bay's Hayward campus is scheduled to be demolished Aug. 17, 2013 for seismic safety reasons. The landmark building's implosion will produce energy similar to a small earthquake that can be used to study and map the nearby Hayward Fault. In partnership with the university, U.S.
Warren Hall on California State University East Bay's Hayward campus is scheduled to be demolished Aug. 17, 2013 for seismic safety reasons. The landmark building's implosion will produce energy similar to a small earthquake that can be used to study and map the nearby Hayward Fault. In partnership with the university, U.S.
Oblique aerial view of San Andreas Fault (between white arrows) in southeastern Coachella Valley, near Red Canyon; view to the west.
Oblique aerial view of San Andreas Fault (between white arrows) in southeastern Coachella Valley, near Red Canyon; view to the west.

Seismic hazard across the State of Hawaii, with high seismic hazards depicted with warm colors (red-orange) and relatively low seismic hazards depicted with cool colors (green). Engineers use these types of maps to prescribe building codes known as Seismic Design Codes (SDC) and create earthquake resistant structures.
Seismic hazard across the State of Hawaii, with high seismic hazards depicted with warm colors (red-orange) and relatively low seismic hazards depicted with cool colors (green). Engineers use these types of maps to prescribe building codes known as Seismic Design Codes (SDC) and create earthquake resistant structures.