An earthquake centered in the Malibu area produced shaking Thursday morning in widespread parts of Southern California from the coast to inland communities.
The quake's initial magnitude of 5.1 was soon downgraded to 4.7. It was followed by more than two dozen aftershocks, including two of magnitude-3.4, with more aftershocks possible in the hours and days ahead.
Centered just north of Malibu, shaking from the 7:28 a.m. quake at a depth of about seven miles was reported in Malibu, Hermosa Beach, La Mirada, Anaheim, Santa Monica, the Hollywood Hills and parts of the San Fernando Valley. Shaking is more likely to be felt from shallow earthquakes, which are those between 0 and about 40 miles deep.
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There were no immediate reports of injuries or significant damage.
Trains will be slowed on Los Angeles' Metro system to check for damage, which is standard procedure following an earthquake.
In February, a magnitude-4.6 earthquake centered northwest of Malibu rattled the region. The afternoon quake in the Santa Monica Mountains also had an active aftershock sequence.
Resident Mark Little said the shaking was different this time around.
"It lasted longer, and the shudder and the shake was more severe," Little said. "And, we had we had nothing broken, but more things moved around."
Scott Richter, owner of Scott’s Malibu Market, said he felt shaking on his way to work. Security camera video from inside the store captured shaking.
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"We were loading our showcases and our baker, Anton, he was putting in our fresh products that we make daily every morning," Richter said. "You could just see him kind of like grasping to the to the showcase there."
Southern California has felt shaking from several earthquakes in recent weeks, including a magnitude-5.2 quake located south of Bakersfield.
"We are having earthquakes. None of them have been damaging. They've all been small," said seismologist Dr. Lucy Jones. "This is a really good reminder that the quiet of the last couple of decades is not our long-term picture."
Phones in the areas received notifications via the state’s MyShake app, which sent 425,217 alerts, according to the governor's office.