Hayward Fault Zone

The Hayward Fault Zone is a right-lateral strike-slip fault roughly 74 miles long, capable of generating destructive earthquakes, running mainly along the base of the hills on the east side of San Francisco Bay through Richmond, Berkeley, Oakland, San Leandro, Hayward, Fremont and San Jose. It functions as a secondary strand within the diffuse transform boundary that also includes the offshore San Andreas Fault and the Calaveras Fault to its east, and in 2016 researchers confirmed it connects beneath San Pablo Bay with the Rodgers Creek Fault, forming a combined Hayward-Rodgers Creek system about 120 miles long. The fault's largest recorded earthquake struck in 1868 at an estimated magnitude of 7.0, causing significant damage across a Bay Area that was then still sparsely populated. This entity documents the Hayward Fault Zone specifically as a geological formation.