In the study, scientists with Harvard University said they now believe the fault line is interconnected. It was previously thought to be a segmented network of smaller faults deep beneath the Palos Verdes Peninsula.
The fault system runs nearly 70 miles along the Southern California coast from the Santa Monica Bay all the way down to Dana Point. Scientists say it has the potential to produce a quake as big as what the San Andreas Fault can produce.
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In a worst-case scenario, they say it would unleash an earthquake that combines the most destructive qualities of the 1994 Northridge earthquake, a 6.7, and the 7.1 Ridgecrest earthquake that hit in 2019.
The study results may not come as a surprise to Southern Californians, but some said it's a good reminder to always be prepared for an earthquake.
"We need to make sure we have our earthquake insurance up-to-date, we need to make sure we have the... water for three days, the canned goods because no one will be able to help us for that amount of time," one woman told Eyewitness News.
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