On October 17, 1989, an earthquake of magnitude 7.1 shook the San Francisco Bay area. With an epicenter in the Santa Cruz mountains, the earthquake killed 67 people, injured 2435, and caused damage of about $6 billion. Earthquakes of this size and greater occur in California at a rate of approximately twelve per century. While catastrophic earthquakes, such as the 1906 San Francisco earthquake, historically have a return period of 250 to 300 years, geologists currently estimate that there is a 50% chance of a great earthquake striking Southern California in the next 30 years. With an estimated Richter magnitude of 8.2, this great Los Angeles earthquake will release almost 1000 times more energy than the 1987 Whittier earthquake or more than 30 times the energy of the Loma Prieta earthquake. The Caliornia Department of Insurance estimates that the economic loss will exceed $50 billion due to such an event. Similar losses are expected from a major earthquake in the San Francisco Bay Area.