The 1906 earthquake and a century of progress in understanding earthquakes and their hazards

Our knowledge of the earliest historic earthquakes in the San Francisco Bay area comes from Spanish mission records, dating back to the founding of Mission Dolores in San Francisco in 1776. The Padres reported on earthquakes damaging their missions, but this record becomes spotty with secularization beginning in the 1830s. After the Gold Rush, numerous newspapers around the region provided excellent coverage. The historical records indicate that the latter two-thirds of the nineteenth century was a period of intense seismic activity throughout the greater San Francisco Bay area (Fig. 1). In fact, 18 magnitude 6.0 or larger earthquakes occurred in the