LOS ANGELES, Dec. 13 (UPI) -- Seismologists are warning the U.S. West Coast could be hit by a catastrophic tsunami, with waves as high as 100 feet or more.
More than a million people in California live in areas that might be affected by a tsunami, and another million visit the state's beaches on a typical summer day, according to a California Seismic Safety Commission study, the Los Angeles Times reported Tuesday.
There have been 80 tsunamis in California during the past 150 years, and geological records show previous waves reached heights of 60 feet or more.
The indications are simple, said Lucy Jones, scientist-in-charge for the U.S. Geological Survey in Southern California -- a long earthquake after which the water recedes.
Jones says beachgoers seeing the water recede should run far inland and stay away from the beach for at least 12 hours, since tsunamis are actually a series of waves that can last for hours.
"You need to know that if you have a five-minute earthquake, there will be a tsunami," Jones told the Times. "That's inevitable.... The really terror scenario is that it's a summer day and there's a million people on the beach."