The Hayward Fault Zone is a geologic fault zone capable of generating significantly destructive earthquakes.
This fault is about 74 mi long, situated 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, Union City, Fremont, and San Jose, in order from north-to-south.
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.
In March 2015, the United States Geological Survey released "UCERF3: A New Earthquake Forecast for California's Complex Fault System."
The upshot, for those who live in the San Francisco Bay Area, is that experts say there is a 72% chance of experiencing a magnitude 6.7 or greater earthquake in the next 30 years. Moreover, there have a 51% chance of a M≥7 (threshold to be considered a "major" quake),
https://en.wikipedia...future_activity