200+ earthquakes in SoCal: What's going on?

LOS ANGELES – There have been more than 277 aftershocks to Tuesday's magnitude 5.2 earthquake in Southern California, two with a magnitude 4.0 or greater – but the likelihood of another, larger shock is still low, the U.S. Geological Survey said.

"Seeing a lot of these smaller events that slow over time is very normal," said Ole Kaven, a research geophysicist with USGS.

A magnitude 5.2 earthquake and a swarm of aftershocks in farmland almost 90 miles northwest of downtown Los Angeles didn't do much damage but did send the Los Angeles Fire Department's 106 stations into earthquake mode, triggering a land, sea and air survey .

The first quake struck at 9:09 p.m. PDT Tuesday as the Los Angeles Dodgers' game was in its seventh inning. While many people reported feeling the earthquake there was no panic and no significant concern, despite the initial shake being followed by several dozen smaller aftershocks that rocked the San Joaquin Valley, according to the U.S. Geological Survey .

The swarm of earthquakes was on an unknown fault that's about 20 to 30 miles west of the San Andreas fault, Kaven said. "It's a known area for earthquakes."

The temblor was enough to set off the state's Earthquake Warning system several seconds before the earthquake hit, sending a loud, strident warning tone to people who had installed the MyShake app on their phones.

While a magnitude 5.2 earthquake might sound big, quakes between 2.5 and 5.4 typically result in minor or no damage, as did this one.

Renowned seismologist Dr. Lucy Jones , who changed how people prepare for earthquakes , took to social media late Tuesday and said that the quake's epicenter was near the White Wolf fault that produced the enormous 1952 rattler but that "it did not appear to be on that fault."

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When was the last big earthquake in California?

The most recent significant earthquake in the state – either a magnitude of 6.5 or greater or that caused loss of life or more than $200,000 damage – was the 6.4-magnitude earthquake that occurred in the Pacific Ocean near Ferndale in 2022, according to the state department of conservation , which tracks "big" earthquakes in California.

That earthquake struck in the morning hours multiple miles west of Ferndale on Dec. 20, 2022, USA TODAY reported . It indirectly caused two deaths and damaged homes and roads in Humboldt County.

What have been the biggest earthquakes in recorded California history?

​​California's largest recorded earthquakes since 1800, ranked by magnitude, according to the California Department of Conservation.

• 7.9 : Jan. 9, 1857, in Fort Tejon. Two killed; created a 220-mile surface scar.
• 7.8 : April 18, 1906, in San Francisco. Possibly 3,000 killed; 225,000 displaced.
• 7.4 : March 26, 1872, in Owens Valley. 27 kille​d; three aftershocks of greater than magnitude 6.
• 7.4 : Nov. 8, 1980, just west of Eureka. Injured 6; $2 million in damage.
• 7.3 : July 21, 1952, in Kern County. 12 killed; three magnitude 6-plus aftershocks in five days.
• 7.3 : June 28, 1992, in Landers. One killed; 400 injured; $9.1 million in damage.
• 7.2 : Jan. 22, 1923, in Mendocino. Damaged homes in several towns.
• 7.2 : April 25, 1992, in Cape Mendocino. 356 injuries; $48.3 million in damage.
• 7.1 : Nov. 4, 1927, southwest of Lompoc. No major injuries, slight damage in two counties.
• 7.1 : Oct. 16, 1999, in Ludlow. Minimal damage due to remote location.​

What am I supposed to do during an earthquake?

It depends on where you are during the event.

Here’s what to do in the following situations, according to Ready.gov :

• Turn your face down and cover your head and neck with a pillow if you’re in bed.
• If you are outside, stay outdoors and away from buildings.
• If you are inside, stay. Avoid doorways and do not run outside.

To protect yourself during an earthquake, drop down to your hands and knees and hold onto something sturdy. Cover your head and neck with your arms and crawl underneath a sturdy table or desk to shelter.

If that’s not available to you, crawl next to an interior wall to get away from windows. If you are under a table or desk, hold onto it with one hand so that if it moves, you can move with it.

Earthquakes happen all the time: You just can't feel them. A guide to how they're measured.

What if I’m driving during an earthquake?

Slow down and pull over as soon as it’s safe, according to the California Highway Patrol. Remain in the vehicle with your seat belt fastened, engine off, and parking brake set. Once the shaking stops, check your vehicle for damage and its occupants for injuries. Only begin driving when it is safe to do so. Once you can start moving again, do so slowly and cautiously, avoiding any areas of the road that appear to be damaged or obstructed, and continue to avoid bridges and ramps.

Contributing: Olivia Munson and Paris Barraza, USA TODAY

This article originally appeared on USA TODAY: 200+ earthquakes in SoCal: What's going on?