A thrust fault that does not rupture all the way up to the surface so there is no evidence of it on the ground. It is buried under the uppermost layers of rock in the crust.
How do I find the nearest fault to a property or specific location?
If you are looking for faults in California use: How Close to a Fault Do You Live? (Bay Area Earthquake Alliance)
The Quaternary Fault and Fold Database has an interactive map for viewing faults within the United States. Click on a fault segment or area to bring up information.
To see faults in California and the rest of the United States (as well as the latest earthquakes) use the Latest Earthquakes Map:
- click on the "Basemaps and Overlays" icon in the upper right corner of the map
- check the box for "U.S. Faults"
The Information by Region section of the Earthquake Hazards Program website has links to many resources for faults and earthquakes for each state in the United States.
Related
What is a fault and what are the different types? What is a fault and what are the different types?
A fault is a fracture or zone of fractures between two blocks of rock. Faults allow the blocks to move relative to each other. This movement may occur rapidly, in the form of an earthquake - or may occur slowly, in the form of creep. Faults may range in length from a few millimeters to thousands of kilometers. Most faults produce repeated displacements over geologic time. During an earthquake, the...
What is the relationship between faults and earthquakes? What happens to a fault when an earthquake occurs? What is the relationship between faults and earthquakes? What happens to a fault when an earthquake occurs?
Earthquakes occur on faults - strike-slip earthquakes occur on strike-slip faults, normal earthquakes occur on normal faults, and thrust earthquakes occur on reverse or thrust faults. When an earthquake occurs on one of these faults, the rock on one side of the fault slips with respect to the other. The fault surface can be vertical, horizontal, or at some angle to the surface of the earth. The...
What is a "Quaternary" fault? What is a "Quaternary" fault?
A Quaternary fault is one that has been recognized at the surface and that has moved in the past 1,600,000 years (1.6 million years). That places fault movement within the Quaternary Period, which covers the last 2.6 million years.
Where can I find a fault map of the United States? Is one available in GIS format? Where can I find a fault map of the United States? Is one available in GIS format?
An online map of United States Quaternary faults (faults active in the last 1.6 million years which places them within the Quaternary Period) is available via the Quaternary Fault and Fold Database. There is an interactive map application to view the faults online. KML (Google Earth-type) files and GIS shape files are also available for download from the site. The interactive map provides detailed...
How do I find fault or hazard maps for California? How do I find fault or hazard maps for California?
An online map of faults ( Quaternary Fault and Fold Database of the United States) that includes California is in the Faults section of the Earthquake Hazards Program website. Choose the Interactive Fault Map, or download KML files and GIS shapefiles from the links on the page. USGS hazard maps, data, and tools for California and other parts of the United States are in the Seismic Hazard Maps and...
Why are there no faults in the Great Valley of central California? Why are there no faults in the Great Valley of central California?
The Great Valley is a basin, initially forming ~100 million years ago as a low area between the subducting ocean plate on the west (diving down under the North American plate) and the volcanoes to the east (now the Sierra Nevada mountains). Since its formation, the Great Valley has continued to be low in elevation. Starting about 20 million years ago the tectonics changed in California and instead...
Why are there so many earthquakes and faults in the Western United States? Why are there so many earthquakes and faults in the Western United States?
This region of the United States has been tectonically active since the supercontinent Pangea broke up roughly 200 million years ago, and in large part because it is close to the western boundary of the North American plate. Since the formation of the San Andreas Fault system 25-30 million years ago, the juxtaposition of the Pacific and North American plates has formed many faults in California...
Why are there so many faults in the Quaternary Faults Database with the same name? Why are there so many faults in the Quaternary Faults Database with the same name?
Many faults are mapped as individual segments across an area. These fault segments are given a different value for name, number, code, or dip direction and so in the database each segment occurs as its own unique entity. For example, the San Andreas Fault has several fault segments, from letters a to h, and fault segment 1h has segments with age of last fault movement from historic (<150 years) to...
Blind Thrust Fault
A thrust fault that does not rupture all the way up to the surface so there is no evidence of it on the ground. It is buried under the uppermost layers of rock in the crust.
Normal Fault
Normal, or Dip-slip, faults are inclined fractures where the blocks have mostly shifted vertically. If the rock mass above an inclined fault moves down, the fault is termed normal, whereas if the rock above the fault moves up, the fault is termed a Reverse fault.
Normal, or Dip-slip, faults are inclined fractures where the blocks have mostly shifted vertically. If the rock mass above an inclined fault moves down, the fault is termed normal, whereas if the rock above the fault moves up, the fault is termed a Reverse fault.
Strike-Slip Fault
Strike-slip faults are vertical (or nearly vertical) fractures where the blocks have mostly moved horizontally. If the block opposite an observer looking across the fault moves to the right, the slip style is termed right-lateral; if the block moves to the left, the motion is termed left-lateral.
Strike-slip faults are vertical (or nearly vertical) fractures where the blocks have mostly moved horizontally. If the block opposite an observer looking across the fault moves to the right, the slip style is termed right-lateral; if the block moves to the left, the motion is termed left-lateral.
Thrust Fault
A thrust fault is a reverse fault with a dip of 45° or less, a very low angle. This animation shows a reverse fault which is a steeper-angle fault, but it moves the same way.
A thrust fault is a reverse fault with a dip of 45° or less, a very low angle. This animation shows a reverse fault which is a steeper-angle fault, but it moves the same way.
Brawley Fault Zone Surface Fractures Across Road
Fresh surface fractures (black arrows) along Brawley Fault Zone and across Ralph Road in response to the 2010 El Mayor-Cucapah earthquake; view to the north. Slight vertical component of slip (2 mm, up on east [right] side) more noticeable at white arrow.
Fresh surface fractures (black arrows) along Brawley Fault Zone and across Ralph Road in response to the 2010 El Mayor-Cucapah earthquake; view to the north. Slight vertical component of slip (2 mm, up on east [right] side) more noticeable at white arrow.
Using bare-earth LiDAR imagery to reveal the Tahoe - Sierra frontal fault zone Lake Tahoe, California.
Using bare-earth LiDAR imagery to reveal the Tahoe - Sierra frontal fault zone Lake Tahoe, California.This video provides a visual example of how airborne LiDAR (Light D
etection And Ranging) imagery penetrates dense forest cover to reveal
an active fault line not detectable with conventional aerial
photography. The video shows an aerial perspective of the range front
Mt. Tallac fault, which is one of five active faults that traverse
Using bare-earth LiDAR imagery to reveal the Tahoe - Sierra frontal fault zone Lake Tahoe, California.
Using bare-earth LiDAR imagery to reveal the Tahoe - Sierra frontal fault zone Lake Tahoe, California.This video provides a visual example of how airborne LiDAR (Light D
etection And Ranging) imagery penetrates dense forest cover to reveal
an active fault line not detectable with conventional aerial
photography. The video shows an aerial perspective of the range front
Mt. Tallac fault, which is one of five active faults that traverse
Denali Fault: Canwell Glacier
Right steps in the Denali fault trace on the Canwell Glacier caused large rhombehedral chasms to form. Patty Craw in background. This photo was on the front page of the Anchorage Daily News.
Right steps in the Denali fault trace on the Canwell Glacier caused large rhombehedral chasms to form. Patty Craw in background. This photo was on the front page of the Anchorage Daily News.
Denali Fault: Fault Trace
Fault trace in trees west of the Mentasta Road. Tallest trees are perhaps 40 feet tall.
Fault trace in trees west of the Mentasta Road. Tallest trees are perhaps 40 feet tall.
San Andreas Fault in SE Coachella Valley
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.
Related
What is a fault and what are the different types? What is a fault and what are the different types?
A fault is a fracture or zone of fractures between two blocks of rock. Faults allow the blocks to move relative to each other. This movement may occur rapidly, in the form of an earthquake - or may occur slowly, in the form of creep. Faults may range in length from a few millimeters to thousands of kilometers. Most faults produce repeated displacements over geologic time. During an earthquake, the...
What is the relationship between faults and earthquakes? What happens to a fault when an earthquake occurs? What is the relationship between faults and earthquakes? What happens to a fault when an earthquake occurs?
Earthquakes occur on faults - strike-slip earthquakes occur on strike-slip faults, normal earthquakes occur on normal faults, and thrust earthquakes occur on reverse or thrust faults. When an earthquake occurs on one of these faults, the rock on one side of the fault slips with respect to the other. The fault surface can be vertical, horizontal, or at some angle to the surface of the earth. The...
What is a "Quaternary" fault? What is a "Quaternary" fault?
A Quaternary fault is one that has been recognized at the surface and that has moved in the past 1,600,000 years (1.6 million years). That places fault movement within the Quaternary Period, which covers the last 2.6 million years.
Where can I find a fault map of the United States? Is one available in GIS format? Where can I find a fault map of the United States? Is one available in GIS format?
An online map of United States Quaternary faults (faults active in the last 1.6 million years which places them within the Quaternary Period) is available via the Quaternary Fault and Fold Database. There is an interactive map application to view the faults online. KML (Google Earth-type) files and GIS shape files are also available for download from the site. The interactive map provides detailed...
How do I find fault or hazard maps for California? How do I find fault or hazard maps for California?
An online map of faults ( Quaternary Fault and Fold Database of the United States) that includes California is in the Faults section of the Earthquake Hazards Program website. Choose the Interactive Fault Map, or download KML files and GIS shapefiles from the links on the page. USGS hazard maps, data, and tools for California and other parts of the United States are in the Seismic Hazard Maps and...
Why are there no faults in the Great Valley of central California? Why are there no faults in the Great Valley of central California?
The Great Valley is a basin, initially forming ~100 million years ago as a low area between the subducting ocean plate on the west (diving down under the North American plate) and the volcanoes to the east (now the Sierra Nevada mountains). Since its formation, the Great Valley has continued to be low in elevation. Starting about 20 million years ago the tectonics changed in California and instead...
Why are there so many earthquakes and faults in the Western United States? Why are there so many earthquakes and faults in the Western United States?
This region of the United States has been tectonically active since the supercontinent Pangea broke up roughly 200 million years ago, and in large part because it is close to the western boundary of the North American plate. Since the formation of the San Andreas Fault system 25-30 million years ago, the juxtaposition of the Pacific and North American plates has formed many faults in California...
Why are there so many faults in the Quaternary Faults Database with the same name? Why are there so many faults in the Quaternary Faults Database with the same name?
Many faults are mapped as individual segments across an area. These fault segments are given a different value for name, number, code, or dip direction and so in the database each segment occurs as its own unique entity. For example, the San Andreas Fault has several fault segments, from letters a to h, and fault segment 1h has segments with age of last fault movement from historic (<150 years) to...
Blind Thrust Fault
A thrust fault that does not rupture all the way up to the surface so there is no evidence of it on the ground. It is buried under the uppermost layers of rock in the crust.
A thrust fault that does not rupture all the way up to the surface so there is no evidence of it on the ground. It is buried under the uppermost layers of rock in the crust.
Normal Fault
Normal, or Dip-slip, faults are inclined fractures where the blocks have mostly shifted vertically. If the rock mass above an inclined fault moves down, the fault is termed normal, whereas if the rock above the fault moves up, the fault is termed a Reverse fault.
Normal, or Dip-slip, faults are inclined fractures where the blocks have mostly shifted vertically. If the rock mass above an inclined fault moves down, the fault is termed normal, whereas if the rock above the fault moves up, the fault is termed a Reverse fault.
Strike-Slip Fault
Strike-slip faults are vertical (or nearly vertical) fractures where the blocks have mostly moved horizontally. If the block opposite an observer looking across the fault moves to the right, the slip style is termed right-lateral; if the block moves to the left, the motion is termed left-lateral.
Strike-slip faults are vertical (or nearly vertical) fractures where the blocks have mostly moved horizontally. If the block opposite an observer looking across the fault moves to the right, the slip style is termed right-lateral; if the block moves to the left, the motion is termed left-lateral.
Thrust Fault
A thrust fault is a reverse fault with a dip of 45° or less, a very low angle. This animation shows a reverse fault which is a steeper-angle fault, but it moves the same way.
A thrust fault is a reverse fault with a dip of 45° or less, a very low angle. This animation shows a reverse fault which is a steeper-angle fault, but it moves the same way.
Brawley Fault Zone Surface Fractures Across Road
Fresh surface fractures (black arrows) along Brawley Fault Zone and across Ralph Road in response to the 2010 El Mayor-Cucapah earthquake; view to the north. Slight vertical component of slip (2 mm, up on east [right] side) more noticeable at white arrow.
Fresh surface fractures (black arrows) along Brawley Fault Zone and across Ralph Road in response to the 2010 El Mayor-Cucapah earthquake; view to the north. Slight vertical component of slip (2 mm, up on east [right] side) more noticeable at white arrow.
Using bare-earth LiDAR imagery to reveal the Tahoe - Sierra frontal fault zone Lake Tahoe, California.
Using bare-earth LiDAR imagery to reveal the Tahoe - Sierra frontal fault zone Lake Tahoe, California.This video provides a visual example of how airborne LiDAR (Light D
etection And Ranging) imagery penetrates dense forest cover to reveal
an active fault line not detectable with conventional aerial
photography. The video shows an aerial perspective of the range front
Mt. Tallac fault, which is one of five active faults that traverse
Using bare-earth LiDAR imagery to reveal the Tahoe - Sierra frontal fault zone Lake Tahoe, California.
Using bare-earth LiDAR imagery to reveal the Tahoe - Sierra frontal fault zone Lake Tahoe, California.This video provides a visual example of how airborne LiDAR (Light D
etection And Ranging) imagery penetrates dense forest cover to reveal
an active fault line not detectable with conventional aerial
photography. The video shows an aerial perspective of the range front
Mt. Tallac fault, which is one of five active faults that traverse
Denali Fault: Canwell Glacier
Right steps in the Denali fault trace on the Canwell Glacier caused large rhombehedral chasms to form. Patty Craw in background. This photo was on the front page of the Anchorage Daily News.
Right steps in the Denali fault trace on the Canwell Glacier caused large rhombehedral chasms to form. Patty Craw in background. This photo was on the front page of the Anchorage Daily News.
Denali Fault: Fault Trace
Fault trace in trees west of the Mentasta Road. Tallest trees are perhaps 40 feet tall.
Fault trace in trees west of the Mentasta Road. Tallest trees are perhaps 40 feet tall.
San Andreas Fault in SE Coachella Valley
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.
Updated Date: August 11, 2026