The Southern California Earthquake Center (
link), an international research collaborative headquartered at the Univ. of Southern California (
link), has developed advanced simulation models of how the ground will shake in a magnitude 8.0 earthquake on the southern San Andreas Fault.
Evidence pulled from sediment in three deep trenches suggests the south end of the San Andreas Fault is likely overdue for a massive quake based on historical averages.
This section of the fault has gone perhaps 140 years longer than the average 180 years between quakes, according to the research reported in the February issue of the Bulletin of the Seismological Society of America.
The study also nixes the idea that lake changes in the now-dry region caused past quakes.
However, the findings do not change existing thinking about the threat of a major quake - potentially measuring 7.0 to 8.0 on the Richter scale - for Southern California, including the Los Angeles Basin. Projections of such a quake in recent years led to the nation's largest-ever drill, the Great Southern California ShakeOut, last year. The 2011 ShakeOut is set for Oct. 20. There's even a video projection of the quake's probable route created by the Southern California Earthquake Center. The last earthquake to originate from the area occurred in about 1690.
