Uh-oh. Is your earthquake kit up-to-date? Stories like this can be panic-inducing, but in this case, that's not such a bad thing. We're overdue for the Big One here -- the earthquake that will make the Northridge quake look like a few minor shakes. The last major San Andreas quake was long before Southern California's population explosion, so who knows the ultimate impact when it hits. But stories like this will at least serve to remind us all: Get ready. From the L.A. Times:
The San Andreas fault is one of California’s most dangerous, and is the state’s longest fault. Yet for Southern California, the last big earthquake to strike the southern San Andreas was in 1857, when a magnitude 7.9 earthquake ruptured an astonishing 185 miles between Monterey County and the San Gabriel Mountains near Los Angeles. It has been quiet since then — too quiet, said Thomas Jordan, director of the Southern California Earthquake Center. “The springs on the San Andreas system have been wound very, very tight. And the southern San Andreas fault, in particular, looks like it’s locked, loaded and ready to go,” Jordan said in the opening keynote talk. Other sections of the San Andreas fault also are far overdue for a big quake. Further southeast of the Cajon Pass, such as in San Bernardino County, the fault has not moved substantially since an earthquake in 1812, and further southeast toward the Salton Sea, it has been relatively quiet since about 1680 to 1690.
Here's a simulation of how the Big One might hit Southern California, from a 2014 ShakeOut scenario: