Hayward Fault Zone - San Francisco

The Hayward Fault Zone is a geologic fault zone capable of generating significantly destructive earthquakes. About 60 kilometers long, it lies mainly along the western base of the hills on the east side of San Francisco Bay. It runs through densely-populated areas, including the cities of Richmond, El Cerrito, Berkeley, Oakland, San Leandro, Hayward, Fremont, and San Jose.
The Hayward Fault is parallel to its more famous (and much longer) westerly neighbor, the San Andreas Fault, which lies offshore and through the San Francisco peninsula. To the east of the Hayward lies the Calaveras Fault. The Hayward Fault merges with these two fault systems south of San Francisco Bay.
North of San Pablo Bay, and somewhat offset from the Hayward Fault is the Rodgers Creek Fault, considered by many to be an extension of the Hayward Fault Zone. Another fault further north, the Maacama Fault, is also considered to be part of the "Hayward Fault subsystem".
While the San Andreas Fault is the principal transform boundary between the Pacific Plate and the North American Plate, the Hayward Fault takes up a share of the overall motion between the plates.