Study: Calif nearly guaranteed major temblor soon
By CBS and Associated Press
LOS ANGELES — The probability California will experience a magnitude 8 or larger earthquake in the next couple of decades has increased, according to the U.S. Geological Survey.
“The new likelihoods are due to the inclusion of possible multi-fault ruptures, where earthquakes are no longer confined to separate, individual faults, but can occasionally rupture multiple faults simultaneously,” said lead author and USGS scientist Ned Field. “This is a significant advancement in terms of representing a broader range of earthquakes throughout California’s complex fault system.”
Compared to the 2008 assessment, earthquakes around magnitude 6.7 — the size of the destructive 1994 Northridge quake — has gone down by 30 percent with a frequency from an average of one per 4.8 years to about one per 6.3 years.
The study also says the likelihood that California will experience a magnitude 8 or larger earthquake in the next 30 years has gone up from about 4.7 percent to about 7 percent.