​Earthquake Swarm Rattles California's Salton Sea

CALIPATRIA, CA— A preliminary magnitude 5.3 earthquake struck near the Salton Sea on Saturday morning following a swarm of smaller quakes, according to the United States Geological Survey. The quakes were reported seven miles from Calipatria.

"Quakes in the Imperial Valley often come in swarms. Which continue until they stop," tweeted seismologist Lucy Jones.

Preceding the larger 10:55 a.m. quake was a series of tremblors ranging from 3.0 to 3.9, all reported just before 11 a.m. An earlier quake was reported at 8 a.m., hours before the earthquake swarm.

A clerk at a Calipatria truck stop said everything is up and running, although some products in the store fell off shelves.

The earthquakes were felt in Imperial County and as far as San Diego County.

"Alright, who felt the quake? We sure did here in Rancho Bernardo - felt a quick jolt," National Weather Service officials tweeted.

In 2016, a series of earthquakes in the region prompted the U.S. Geological Survey to issue a warning of the increased risk of a large quake in Southern California because more than 200 temblors epicentered less than four miles from the San Andreas Fault near the Salton Sea.

"Past swarms have remained active for 1 to 20 days, with an average duration of about a week," the USGS previously reported.

No injuries or structural damage were immediately reported.

The American Red Cross has recommended the following earthquake safety tips:

• Become aware of fire evacuation and earthquake safety plans for all of the buildings you occupy.
• Pick safe places in each room of your home, workplace and/or school. A safe place could be under a piece of furniture or against an interior wall away from windows, bookcases or tall furniture that could fall on you.
• Practice "drop, cover and hold on" in each safe place. If you do not have sturdy furniture to hold on to, sit on the floor next to an interior wall and cover your head and neck with your arms.
• Keep a flashlight and sturdy shoes by each person's bed in case the earthquake strikes in the middle of the night.
• Make sure your home is securely anchored to its foundation.
• Bolt and brace water heaters and gas appliances to wall studs.
• Bolt bookcases, china cabinets and other tall furniture to wall studs.
• Hang heavy items, such as pictures and mirrors, away from beds, couches and anywhere people sleep or sit.
• Brace overhead light fixtures.
• Install strong latches or bolts on cabinets. Large or heavy items should be closest to the floor.
• Learn how to shut off the gas valves in your home and keep a wrench handy for that purpose.
• Learn about your area's seismic building standards and land use codes before you begin new construction Keep and maintain an emergency supplies kit in an easy-to-access location.

See Also:

• Earthquake Preparedness: Must-Have List
• Earthquake Preparedness For CA Pet Owners

The City News Service and Patch staffers Kat Schuster and Paige Austin contributed to this report.