San Andreas Fault
...al investigations in which the cores from drill-holes along the bridges across San Francisco Bay are being extensively tested to learn how these soft rocks will respond during an earthquake. This information is especially important along the eastern span of the Bay Bridge, where new construction is planned. The third thing is shallow seismic imaging of Bay Area faults which gives information about the locations, recency of motion, and direction of motion of faults can be gathered from shallow, high-resolution seismic imaging. The final and fourth thing is airbone geophysical surveys. How this work is the magnetic signature from different types of rocks can be measured from the air. This technique allows us to identify fault structures in the offshore region where they are difficult to identify. The 1906 San Francisco earthquake is thought to have originated along the offshore part of the San Andreas fault, west of the Golden Gate. Along the San Andreas Fault, the segment considered most likely to rupture is near Parkfield CA. Earlier this centurey it produced a series of identical earthquakes at regular times. The USGS scientist have correctly predicted several earthquake predictions in the Parkfield area between the years of 1988 to 1992. The segment of the San Andreas fault that broke in the 1...