Up and down the West Coast, the ShakeOut drill was scheduled to begin at 10:19 a.m. PDT with a cellphone-rattling test alert from the region's ShakeAlert earthquake warning system.
The U.S. Geological Survey said it was likely due to a mix-up in time zones set in the test alert system.
Political Cartoons View All 1211 ImagesThe ShakeOut earthquake drills are coordinated by the Southern California Earthquake Center at the University of Southern California.
The ShakeOut drill originated in California in 2008.
The first one was based on a scenario of a magnitude 7.8 earthquake on the southern section of California’s mighty San Andreas Fault.
Organizations:
—, Geological Survey, Southern California Earthquake, University of Southern, Schools
Locations:
SACRAMENTO, Calif, California, West Coast, U.S, California's, Sacramento, San Joaquin, Delta, University of Southern California