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The energy released in earthquakes can produce five different types of hazards: <br />Fault rupture <br />Ground shaking <br />Liquefaction <br />Earthquake -induced landslides <br />Tsunamis and seiches <br />5.1.2 Historic Bay Area Earthquake Occurrences <br />The Bay Area has experienced significant, well-documented earthquakes. In 1868, a <br />significant earthquake occurred on the Hayward fault with an estimated magnitude of <br />6.8-7.0. The fault ruptured the surface of the earth for more than 20 miles and significant <br />damage was experienced in Hayward and throughout Alameda County, and as far away as <br />San Francisco, Santa Rosa, and Santa Cruz. The M7.8 1906 earthquake on the San Andreas <br />Fault, centered just off the coast of San Francisco, devastated San Francisco and caused <br />extensive damage in Oakland, San Jose, and Santa Rosa. More recently, the M6.9 1989 <br />Loma Prieta earthquake caused severe damage in Santa Cruz and the surrounding <br />mountains, where it was centered, as well as fatal damage 50 miles away in Oakland and <br />San Francisco. Moderate earthquakes are much more common in the Bay Area; twenty- <br />two have occurred in the last 178 years, averaging every eight years.4 The 2014 South <br />Napa earthquake is a reminder of the strong shaking that even a moderate magnitude 6.0 <br />earthquake can produce in a localized area. Figure 2 charts Bay Area earthquakes over <br />the past 165 years. Because the 1906 earthquake released so much energy and stress on <br />regional faults when it ruptured, the last 100 years have been relatively seismically quiet. <br />As faults restore their stress and energy builds <br />1 uses (21 <br />Ellsworth, <br />01 <br />