Moderate earthquakes strike near San Diego over weekend

BRAWLEY, Calif. (AP) AUG 27, 2012 — A series of small to mod­er­ate earth­quakes that shat­tered win­dows and knocked trailer homes off their foun­da­tions is putting this small farm­ing town east of San Diego on edge as they con­tinue to feel jolts that sci­en­tists said could last for days.

The largest quake, reg­is­tered at a mag­ni­tude 5.5, struck at 1:57 p.m. Sun­day and was cen­tered about three miles north­west 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 shook 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 and ren­dered them inhab­it­able, said Maria Peinado, a spokes­woman for the Impe­r­ial County Emer­gency Oper­a­tions Cen­ter. A red-tiled roof appar­ently col­lapsed and landed on a wooden fence.

Spo­radic power out­ages, at one point affect­ing 2,500 Impe­r­ial Irri­ga­tion Dis­trict cus­tomers, also prompted author­i­ties to evac­u­ate 49 patients from one of the county’s two hos­pi­tals, Peinado said. Police also received numer­ous calls about gas leaks and water line breaks.

By late Sun­day, a magnitude-5.1 quake fol­lowed by sev­eral more with mag­ni­tudes of at least 4.0 shook the area.

‘‘It’s not uncom­mon for us to have earth­quakes out here, but at this fre­quency and at this mag­ni­tude it’s fairly unusual,’’ said George Nava, the mayor of Braw­ley, a town of 25,000.

‘‘And the fact that the after­shocks keep com­ing are a lit­tle alarm­ing,’’ he said.

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

‘‘It felt like there was quake every 15 min­utes. One after another. My kids are small and they’re scared and don’t want to come back inside,’’ said Mike Patel, who man­ages Town­house Inn & Suites.

A TV came crash­ing down and a few light fix­tures broke inside the motel, Patel said.

The first quake, with a mag­ni­tude of 3.9, occurred at 10:02 a.m. The USGS said more than 300 after­shocks struck the same approx­i­mate epicenter.

Some shak­ing was felt along the San Diego County coast in Del Mar, some 120 miles from the epi­cen­ter, as well as in south­west­ern Ari­zona 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,’’ Jones said.

The last major swarm was in 2005, fol­low­ing a magnitude-5.1 quake, she said.

Posted by Randa Wagner on Aug 27 2012. You can follow any responses to this entry through the RSS Feed. Both comments and pings are currently closed.