Small to moderate quake cluster strikes southeastern California

SAN DIEGO - Dozens of small to moderate earthquakes struck southeastern California on Sunday, knocking trailer homes off their foundations, shattering windows and rattling nerves in a small farming town east of San Diego.

The largest quake, at 1:57 p.m., registered at a magnitude 5.5 and was centered about three miles northwest of the town of Brawley, said Robert Graves, a geophysicist with the U.S. Geological Survey. Another quake about an hour and a half earlier registered at magnitude 5.3.

No injuries were reported.

More than 30 additional earthquakes with magnitudes of at least 3.5 jiggled the same area near the southern end of the Salton Sea, Graves said.

"The type of activity that we're seeing could possibly continue for several hours or even days," Graves said.

The quakes pushed 20 mobile homes at a trailer park off their foundations, displacing the families that lived in them, said Maria Peinado, a spokeswoman for the Imperial County Emergency Operations Center.

Sporadic power outages affecting 2,500 Imperial Irrigation District customers also prompted authorities to evacuate some patients from one of the county's two hospitals.

At the El Sol Market in Brawley, food packages fell from shelves and littered the aisles.

Several glasses and a bottle of wine crashed to the floor and shattered at Assaggio, an Italian restaurant in Brawley, owner Jerry Ma said. The shaking was short-lived but intense, he said.

A Brawley police dispatcher said several downtown buildings sustained minor damage.

The first quake, with a magnitude of 3.9, occurred at 10:02 a.m. The USGS said more than 100 aftershocks struck around the epicenter, about 16 miles north of El Centro.

Some shaking was felt along the San Diego County coast in Del Mar, about 120 miles from the epicenter, as well as in the Coachella Valley, southern Orange County and parts of northern Mexico.

USGS seismologist Lucy Jones said earthquake swarms are characteristic of the region, known as the Brawley Seismic Zone. "The area sees lots of events at once, with many close to the largest magnitude, rather than one main shock with several much smaller aftershocks."