Ridgecrest temblors increase chance of San Andreas earthquake


The greater Los Angeles area lies near the San Andreas Fault, which researchers said Monday is at greater risk for an earthquake following two tremblors last year. Photo courtesy of Temblo

July 13 (UPI) -- The Ridgecrest temblors that hit California last year could make a San Andreas earthquake more likely, a new study found.

The likelihood is higher because the 2019 temblors in Ridgecrest, Calif., "stressed the Garlock Fault," and the Garlock Fault links the Ridgecrest faults with the San Andreas fault, researchers said in the study, published Monday in the Bulletin of the Seismological Society of America.

The 6.4-magnitude and 7.1-magnitude Ridgecrest earthquakes caused no deaths and modest damage because they were in a remote desert area of Southern California, but they "could have far-reaching effects," according to researchers.

If another big earthquake ruptures the Garlock, it could cause a chain reaction that triggers a San Andreas earthquake north of Los Angeles, researchers said. The probability of such a rupture in the next year remains low at a 2.3 percent chance, but that's still 100 times higher than previous models have found.

"So, the sky is not falling, co-author Ross Stein, CEO of Temblor, which assesses the risks of earthquakes, told National Geographic. "But it is significantly higher, in our judgment, than what it would have been had the Ridgecrest earthquake not occurred."