Skip to main content

Magnitude 5.2 Earthquake Hits Anza-Borrego Area

Magnitude 5.2 Earthquake Hits Anza-Borrego Area


Thomas Rockwell, earthquake geologist, San Diego State University


A strong and very shallow earthquake struck early Friday in the Anza-Borrego Desert State Park in northern San Diego County, followed by several aftershocks, the U.S. Geological Survey reported.

The temblor struck at 1:04 a.m. at a depth of 0.6 of a mile with a magnitude of 5.2, according to the USGS.

A quake of such strength can generate considerable damage, but there were no immediate reports of injuries or damage in San Diego or Riverside counties, and no threat of a tsunami, authorities said.

"We did not have any reports of damage or injuries from earthquake," San Diego Police Chief Shelley Zimmerman said, adding: "This is a good reminder to have a plan in place."

However, the earthquake triggered a minor rockslide on Montezuma Valley Road, about 14 miles southeast of Borrego Springs. California Highway Patrol officers worked to clear the road, the CHP reported.

The quake's epicenter was 13 miles north-northwest of Borrego Springs in San Diego County and 16 miles south-southwest of La Quinta in Riverside County. It was strong enough to be felt in Los Angeles, as well as in San Bernardino and Orange counties and in parts of Mexico.

Location of earthquake

The earthquake occurred along the San Jacinto Fault, historically the most active fault in Southern California, said seismologist Lucy Jones. It was near a magnitude 6 earthquake in 1937 and a magnitude 5.3 earthquake in 1980, Jones reported.

"We have never seen a San Andreas earthquake triggered by a San Jacinto earthquake," Jones wrote on Twitter, referring to the state's most famous fault, the one along which the so-called "big one" is expected to hit someday.

"Every earthquake has a 5 percent of triggering an aftershock that is bigger than itself — always within a few miles of location of the first earthquake," Jones wrote.

There were at least eight aftershocks in the same general area within 3 hours and 10 minutes. The strongest were magnitude 3.5 shakers at 1:06 a.m., 1:33 a.m. and 4.14 a.m. — all at a depth of slightly more than 6 miles.

Cathy Gaffney, manager of the Hacienda del Sol inn in Borrego Springs, said she woke up when the quake hit.

"It's definitely something that starts your heart up at one in the morning," she said. Gaffney said the quake felt similar to the one centered in Mexicali that hit on Easter Sunday 2010.

She said there was no damage at the inn, but a few things did fall off the shelves.

Want more KPBS news?
Find us on Twitter and Facebook, or sign up for our newsletters.

To view PDF documents, Download Acrobat Reader.