October 21, 1868 Hayward Fault Earthquake

Because of its location in the heart of the Bay Area, then having a total population of about 260,000, and its magnitude, variously estimated as between 6.8 and 7.0, this earthquake was one of the most destructive in California history. Property loss was extensive and 30 people were killed. Read more »

• The Hayward Fault—Is It Due for a Repeat of the Powerful 1868 Earthquake?

  USGS scientists describe this fault as a tectonic time bomb, due anytime for another magnitude 6.8 to 7.0 earthquake. Because such a quake could cause hundreds of deaths, leave thousands homeless, and devastate the region’s economy, the USGS and other organizations are working together with new urgency to help prepare Bay Area communities for this certain future quake.

New Science and Products

• Virtual Tour of the 1868 Hayward Earthquake in Google Earth ^TM

  Interactive self-guided tour of San Francisco Bay Area faults and earthquake history featuring ground-shaking maps, historic photographs, quotes from earthquake survivors, and more.

• Intensity Maps for the 1868 Hayward Earthquake

  Modified Mercalli Intensity maps for the Hayward earthquake plotted in ShakeMap format.

• Active Traces of the Hayward Fault

  Map showing active fault traces within the Hayward Fault Zone, including a virtual tour of the Hayward fault in the east San Francisco Bay Region that can be viewed in Google Earth ^TM.

• Geometry and Evolution of the Hayward Fault

  Geophysical data along the Hayward Fault are used to investigate the nature, spatial relationship, and evolution of the Hayward Fault Zone.

• Three-dimensional geologic map of the Hayward fault, northern California: Correlation of rock units with variations in seismicity, creep rate, and fault dip (15 MB pdf)

  A recent paper on the Hayward Fault Model by Russell Graymer and others.

Field Guides

• Where’s the Hayward Fault? A Green Guide to the Fault

  Self-guided field trips to one of North AmericaÕs most dangerous earthquake faults, the Hayward Fault. Locations were chosen because of their easy access using mass transit and/or their significance relating to the natural and cultural history of the East Bay landscape.

• 2006 Field Guide to the Hayward Fault (13 MB pdf)

  A detailed geologic and architectural field guide to 11 stops along the Hayward Fault, including UC Berkeley Campus and Memorial Stadium, Point Pinole, Cragmont School in Berkeley, Oakland City Hall, and old City Hall in Hayward and it includes discussion of the 1868 earthquake. This guide was published by the Geological Society of America in 2006 as part of the 1906 San Francisco Earthquake Centennial Meeting.

• Field Guide to the Hayward Fault (29 MB pdf)

  Download a 2001 U.S. Geological Survey Field Guide to the Hayward Fault in Downtown Hayward and at the Caldecott Tunnel (between Orinida and Oakland) and to the 1998 Fremont Peak landslide.

• Field Guide to the Hayward Fault, Downtown Hayward

  Explore the Hayward Fault in Hayward using this online field guide prepared for the 2000 U.S. Geological Survey Open House.

See Also

• The Accumulation of Interseismic Strain Along the Hayward Fault

  Interseismic surface deformation along the Hayward Fault monitored with Interferometric Synthetic Aperture Radar (InSAR) and the Global Positioning System (GPS).

• Hayward Fault Earthquake Loss Scenario

  This 1996 report by the Earthquake Engineering Research Institute describes what losses are expected to result from magnitude 7 earthquake on the northern end of the Hayward Fault.

• 1868 Hayward Earthquake Alliance

  This web site was created to help coordinate and promote efforts and activities between organizations throughout the greater San Francisco Bay Area planning to commemorate the earthquake.

• Berkeley Seismological Laboratory

  More information about the earthquake, including location parameters, maps, photos, and seismograms.

• Hayward Fault Subsystem

  More information about the Hayward fault subsystem.