Southern California rattled by swarm of quakes

LOS ANGELES — A series of earthquakes peaking with a magnitude 5.1 shaker struck Southern California on Friday evening, causing a rock slide, water main breaks and shattered glass throughout northwestern Orange County, but there were no immediate reports of injuries.

The first of a swarm of earthquakes hit the border of La Habra and Brea shortly after 8 p.m. with a 3.6 temblor. About an hour later, at 9:09 p.m., a 5.1 shock hit, followed by at least two more aftershocks in the 3-point range in the next half-hour. At least 20 aftershocks had been recorded by late Friday.

U.S. Geological Survey seismologist Lucy Jones said the 5.1 quake has a 5 percent chance of being a foreshock of a larger temblor.

“There could be even a larger earthquake in the next few hours or the next few days,” Jones said during a media briefing at the California Institute of Technology.

Residents across Orange and Los Angeles counties and the Inland Empire reported swinging chandeliers, fireplaces dislodging from walls and lots of rattled nerves, but damage appeared to be relatively minor. The shake caused a rock slide in Carbon Canyon, causing a car to overturn, according to the Brea Police Department. Fullerton police received reports of water main breaks and windows shattering, but primarily had residents calling about burglar alarms being set off by the quake.

At Disneyland in Anaheim, all rides were halted as a precaution but no damage or injuries were reported — other than ceiling tiles falling in the police station, Sgt. Daron Wyatt said.

Experts said that based on preliminary data, the series of earthquakes appeared to have occurred on the Puente Hills thrust fault, which stretches from the San Gabriel Valley to downtown Los Angeles.

Friday night’s 5.1 quake was relatively shallow, which “means the shaking is very concentrated in a small area,” said Caltech seismologist Egill Hauksson. Hauksson said the quake sequence was unusual in that the 5.1 quake was preceded about an hour earlier by a weaker foreshock.

Scientists are particularly concerned about the Puente Hills thrust fault because it goes directly underneath downtown Los Angeles.

“This is the fault that could eat L.A.,” seismologist Sue Hough told the Los Angeles Times in 2003.

On Friday, though, police and fire departments in Los Angeles reported no damage.

Although the shaking was felt throughout the region, it didn’t rattle the professionalism at Walt Disney Concert Hall. Microphones above the stage swung back and forth and the hall shook, but the orchestra continued playing.

“The L.A. Philharmonic should get combat pay,” said audience member Michael Healy of Studio City.

Distributed by MCT Information Services