A 1972 law requires the state to publish detailed maps of active earthquake fault zones. The California Geological Survey has amended those maps over the years, frequently shrinking the size of the hazard zones. The state has changed 161 maps out of 708, including one that carved a sharp angle around Pescadero High School in coastal San Mateo County. Read more about the altering of California's fault-zone maps.
Drag the green button in the center of the image to see differences between the maps.