STANFORD, Calif. - Scientists at Stanford warned of a large earthquake possibly brewing in Silicon Valley.
The new study found that two faults, known together as Foothill Thrust Belt, could produce a quake as big as the Loma Prieta that rattled the Bay Area in 1989.
They said the 6.9 magnitude shake could happen every 250-300 years along this belt.
While it's a cautionary warning, seismologists admit they have no way of predicting exactly when a large quake could strike.
California uses science, state-of-the-art ground motion monitoring, and new and existing alerting methods to deliver warnings to residents' cell phones before the strongest shaking arrives.