Magnitude 4.9 earthquake near Palm Desert briefly shakes San Diego County

A magnitude 4.9 earthquake occurred at 5:56 p.m. Monday about 17 miles northeast of Palm Desert in Riverside County, producing shaking that was felt throughout San Diego County, the U.S. Geological Survey said.

The shaking spread all the way to the Southern California coastline, drawing notice from San Diego and Chula Vista to Long Beach and Malibu.

A 3.5 after shock followed at 6:50 p.m.

The main quake broke near the San Andreas fault, an 800-mile-long system, part of which extends through the Cajon Pass area and Coachella Valley and into the Salton Sea.

“We periodically have quakes of this size, and they rarely lead to something bigger,” said Tom Rockwell, a seismologist at San Diego State University. “But 5% of the time, they do give us something bigger.

“We haven’t had a big quake on the San Andreas for 300 years. The interval time for one is about 150 years.”