Geologic Trips, Bay Area Faults
San Andreas Lake
The trace of the 1906 San Francisco earthquake passes through this point on the abutment San Andreas Dam and then northwest through the San Andreas Lake toward the small peninsula (distant center). The San Andreas Dam is an earthfill embankment that is 720 feet long and was built across the valley that was formed by the San Andreas fault zone. The dam was displaced nine feet to the northwest during the earthquake, but did not fail.
It is this lake that gave its name to the San Andreas fault. In 1991 this monument was placed at the spot where the fault cut through the abutment for the dam.