The 1868 Hayward earthquake occurred in the

San Francisco Bay Area The San Francisco Bay Area, often referred to as simply the Bay Area, is a populous region surrounding the San Francisco, San Pablo, and Suisun Bay estuaries in Northern California. The Bay Area is defined by the Association of Bay Area Go ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, United States on October 21. With an estimated moment magnitude of 6.3–6.7 and a maximum Mercalli intensity of IX (''Violent''), it was the most recent large

earthquake An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...

to occur on the

Hayward Fault Zone The Hayward Fault Zone is a right-lateral strike-slip geologic fault zone capable of generating destructive earthquakes. This fault is about long, situated mainly along the western base of the hills on the east side of San Francisco Bay. It runs ...

. It caused significant damage and a number of deaths throughout the region, and was known as the "Great San Francisco earthquake" prior to the 1906 San Francisco earthquake and fire.

Earthquake

The earthquake occurred at 7:53 a.m. on October 21, 1868. Its

epicenter The epicenter, epicentre () or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates. Surface damage Before the instrumental pe ...

was likely located near

Hayward, California Hayward () is a city located in Alameda County, California in the East Bay subregion of the San Francisco Bay Area. With a population of 162,954 as of 2020, Hayward is the sixth largest city in the Bay Area and the third largest in Alameda Coun ...

, and its magnitude has been estimated to have been 6.3–6.7 on the

moment magnitude scale The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. It was defined in a 1979 pape ...

. At the surface,

ground rupture In seismology, surface rupture (or ground rupture, or ground displacement) is the visible offset of the ground surface when an earthquake rupture along a fault affects the Earth's surface. Surface rupture is opposed by buried rupture, where the ...

was traced for , from

San Leandro San Leandro (Spanish for " St. Leander") is a city in Alameda County, California, United States. It is located in the East Bay of the San Francisco Bay Area; between Oakland to the northwest, and Ashland, Castro Valley, and Hayward to the sout ...

to what is now the Warm Springs District in Fremont.

Damage

The town of Hayward experienced the most damage, with nearly every building destroyed or significantly damaged in the earthquake. The Alameda County Courthouse in San Leandro was destroyed, which resulted in the re-location of the County Seat to Oakland, its current site. The

adobe Adobe ( ; ) is a building material made from earth and organic materials. is Spanish for ''mudbrick''. In some English-speaking regions of Spanish heritage, such as the Southwestern United States, the term is used to refer to any kind of e ...

chapel of

Mission San José Mission San José may refer to: *Mission San José (California), a Spanish mission in Fremont, California * Mission San Jose, Fremont, California, a neighborhood * Mission San Jose High School, a high school in Fremont, California *Mission San José ...

in what is now Fremont was also destroyed, as were several buildings in San Jose, San Francisco and throughout

Alameda County Alameda County ( ) is a List of counties in California, county located in the U.S. state of California. As of the 2020 United States Census, 2020 census, the population was 1,682,353, making it the 7th-most populous county in the state and List ...

. Damage was reported from

Santa Rosa Santa Rosa is the Italian, Portuguese and Spanish name for Saint Rose. Santa Rosa may also refer to: Places Argentina *Santa Rosa, Mendoza, a city * Santa Rosa, Tinogasta, Catamarca * Santa Rosa, Valle Viejo, Catamarca *Santa Rosa, La Pampa * Sa ...

in the north to Gilroy and Santa Cruz in the south. Thirty deaths were attributed to the earthquake.

Intensity

The

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

estimates that Hayward experienced shaking measuring IX (''Violent'') on the

modified Mercalli scale The Modified Mercalli intensity scale (MM, MMI, or MCS), developed from Giuseppe Mercalli's Mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. It measures the eff ...

. San Leandro experienced shaking measuring VIII (''Severe''), while

San Francisco San Francisco (; Spanish language, Spanish for "Francis of Assisi, Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the List of Ca ...

and

Oakland Oakland is the largest city and the county seat of Alameda County, California, United States. A major West Coast port, Oakland is the largest city in the East Bay region of the San Francisco Bay Area, the third largest city overall in the Bay A ...

experienced shaking measuring VII (''Very strong'').

References

External links

1868 Hayward Earthquake AllianceImages from the 1868 earthquake aftermath
–

The Bancroft Library The Bancroft Library in the center of the campus of the University of California, Berkeley, is the university's primary special-collections library. It was acquired from its founder, Hubert Howe Bancroft, in 1905, with the proviso that it retai ...

Photos of damage in San Francisco following the 1868 earthquake
–

San Francisco Public Library The San Francisco Public Library is the public library system of the city and county of San Francisco. The Main Library is located at Civic Center, at 100 Larkin Street. The library system has won several awards, such as ''Library Journals L ...

Prepare for big ruptures on Hayward fault, scientists say
–

Stanford University Stanford University, officially Leland Stanford Junior University, is a private research university in Stanford, California. The campus occupies , among the largest in the United States, and enrolls over 17,000 students. Stanford is consider ...

The 150th Anniversary of the Damaging 1868 Hayward Earthquake: Why It Matters and How We Can Prepare for Its Repeat
– Tom Brocher (USGS) {{Hayward, California

1868 Events January–March * January 2 – British Expedition to Abyssinia: Robert Napier leads an expedition to free captive British officials and missionaries. * January 3 – The 15-year-old Mutsuhito, Emperor Meiji of Jap ...

Hayward earthquake History of the San Francisco Bay Area Hayward earthquake History of Hayward, California October 1868 events 1868 natural disasters in the United States

Earthquake

Damage

Intensity

See also

References

Further reading

External links