More Earthquakes Rattle SoCal After Strong Quake In Imperial County

IMPERIAL COUNTY, CA — A magnitude 4.1 earthquake struck late Tuesday night in Imperial County, east of San Diego.

The quake was recorded at 11:53 p.m. about 6.2 miles north of Westmorland, which is part of the El Centro Metropolitan Area, according to the United States Geological Survey. The epicenter of the quake was roughly 6.7 miles deep.

A few smaller quakes were recorded within minutes in the same area. A magnitude 2.5 quake struck first at 11:49 p.m. about 6.2 miles west of Calipatria in Imperial County, according to the USGS. A 2.6-magnitude quake was recorded at 11:55 p.m., followed by a 2.5-magnitude quake at 11:56 p.m.

Residents reported feeling the largest quake in Imperial, Riverside and San Diego counties, according to the USGS’s “Did You Feel It?” map.

The quakes came after a magnitude 4.8 earthquake struck early Monday morning near El Centro and was followed by a series of smaller quakes. The earthquake swarm was one of the strongest to hit Southern California in years.

As of 12:35 p.m. Tuesday, the Southern California Seismic Network had recorded 232 “events” in the swarm, with the smallest being a 0.8-magnitude quake.

“More activity is expected in the next few days, swarm activity in Southern California can continue for hours, days, weeks, months or years,” Southern California Seismic Network wrote.

Monday’s earthquake activated the USGS ShakeAlert Earthquake Early Warning System, which detects significant quakes early enough so that alerts can be delivered to residents and automated systems potentially seconds before shaking arrives. The early warning system estimated the quake above magnitude 5.0, so alerts were sent to cell phones through apps such as MyShake and ShakeReadySD, according to the USGS.

The California Governor’s Office of Emergency Services issued a statement Monday that it was closely monitoring the impacts of the earthquake and aftershocks and continues to work with partners to assess any damage.