Expect big Calif. quake by 2037

California faces an almost certain risk of being rocked by a strong earthquake by 2037, scientists said Monday in the first statewide temblor forecast.

New calculations reveal there is a 99.7% chance a magnitude 6.7 quake or larger will strike in the next 30 years. The odds of such an event are higher in Southern California than Northern California, 97% versus 93%.

The last time a jolt this size rattled California was the 1994 Northridge disaster, which killed 72 people, injured more than 9,000 and caused $25 billion in damage.

"It basically guarantees it's going to happen," said Ned Field, a seismologist with the U.S. Geological Survey in Pasadena and lead author of the report.

California is one of the most seismically active regions in the world. More than 300 faults crisscross the state, which sits atop two of Earth's major tectonic plates, the Pacific and North American plates. About 10,000 quakes each year rattle Southern California alone, although most of them are too small to be felt.