LOCATION ANALYSIS

Find your nearest
fault line.

Locate a site. Explore nearby faults.
Measure the distance in between.

LatitudeLongitude

Decimal degrees · WGS 84 · latitude, longitude
Default: Cornerstone Sunnyvale · 1259 Oakmead Parkway (approximate address location)

Fault classesClass AClass BUnits

Preparing your map…

Approximate distances · location accuracy

Fault lines represent mapped interpretations, not surveyed positions. USGS warns that zooming in can exceed the accuracy of the fault data. Accuracy varies with the source mapping and trace type.

This KMZ does not supply numerical positional uncertainty for each trace, so a defensible ± km or mi range cannot be calculated. “Well constrained” and mapped scale are context, not a numeric error bound. Decimal places show calculation precision, not location accuracy. Address or selected-point uncertainty adds further error.

Use these distances for preliminary screening. Consult the original fault report and appropriate site-specific investigation for engineering or regulatory decisions.

USGS fault-map accuracy guidance ↗

⌖A location is all you need.

Enter coordinates or a street address above.
You can also click anywhere on the map.

About the data & measurements

Source: U.S. Geological Survey (USGS) fault data, filtered to include California faults only and supplied as California Faults.kmz. Classes come from its “Fault Class” attribute, not line colors. Unclassified traces are excluded. Distances are horizontal, spherical great-circle distances to the nearest mapped line segment, using all original vertices. They are not driving distances or distances to a fault at depth.

The file contains historical review dates. Results describe this dataset and do not establish current regulatory fault zones or site safety.

Map tiles require internet. As you type, address text is sent to Photon (Komoot) for suggestions. Full address searches are sent to the US Census. Coordinate calculations run in your browser.

Geocoder documentation ↗

CALIFORNIA FAULT NETWORK

Map style

Class A faultClass B faultShortest distance

Click a fault for details · Click elsewhere to analyze