The faults that drive the country’s earthquake hazard, each traced from the USGS Quaternary Fault and Fold Database. Click a fault on the map or in the list for its full map, how it moves, its great earthquakes, and the odds of the next one.
These are the named faults with their own pages. The full fault line map draws all of the more than 2,000 mapped fault systems in the country, or check the faults near any address. Buying a home in California? See what the state’s fault-line law (the Alquist-Priolo Act) actually requires.