A moderate 4.6-magnitude earthquake struck just northwest of Malibu on Friday afternoon, causing light to moderate shaking across a widespread part of Southern California. The quake occurred at around 1:55 pm local time about 7 miles northwest of Malibu in the Santa Monica Mountains, according to the United States Geological Survey (USGS).
While the earthquake was centered in a sparsely populated area, shaking was felt over a large region from the coast to inland valleys and cities. Areas reporting light to moderate shaking included Malibu, Santa Monica, Pacific Palisades, Beverly Hills, Westwood, Brentwood, Venice, Marina Del Rey, Playa Del Rey, Los Angeles, Hollywood, Northridge, Reseda, Encino, Sherman Oaks, Studio City, Glendale, Pasadena, Alhambra, Long Beach, Irvine, Anaheim, and parts of Orange and San Diego counties. No major damage or injuries have been reported so far.
The quake triggered a series of small aftershocks in the same region, with at least 16 felt tremors of magnitude 2.5 or less recorded within 90 minutes of the main shock. Seismologists say there is a small chance the quake was a foreshock preceding a larger event, but this risk diminishes rapidly over time.
“It’s got a very robust aftershock sequence,” said prominent seismologist Dr. Lucy Jones. “Aftershocks may continue over the next days to weeks, mostly unfelt but some of which may be felt strongly. The number of aftershocks will drop off over time.”
Residents across the greater Los Angeles metro area reported feeling light to moderate shaking lasting 5-10 seconds. The quake was felt as a sharp jolt or roll, causing light house rattling and shaking of hanging objects. Many Angelenos took to social media to report their experiences.
“It was a major jolt. We all figured out what was going on. The patients were fine, and they continued on with the dentistry. It’s always a little nerve-racking,” said Marla Dailey, who was working in a dental office in Thousand Oaks when the quake struck.
The Los Angeles Fire Department said it was conducting routine post-earthquake surveys to check for any possible damage in the city. So far there are no reports of significant damage or disruption, though minor cosmetic damage is possible. The U.S. National Tsunami Warning Center confirmed no tsunami threat from the quake.
Seismologist Lucy Jones said the quake likely occurred on the Malibu Coast Fault, which runs along the coastline of the Santa Monica Mountains through Pacific Palisades, Santa Monica, Malibu and other beach cities. It is one of several active faults crisscrossing the Los Angeles metro.
Friday’s quake happened on the same calendar date as the deadly 1971 San Fernando Earthquake, a magnitude 6.5 temblor that killed over 60 people and caused widespread damage in the San Fernando Valley. However, today’s Malibu quake is not related to the San Fernando fault system and the timing is coincidental, experts say.
The shaking serves as an important reminder for Southern California residents to be prepared. “We live in earthquake country and need to be ready,” said Jones. She advises having an earthquake kit with at least a 7 day supply of essentials and securing furniture that could topple over and cause injury.
Small to moderate earthquakes frequently rattle Southern California, which sits along the volatile San Andreas fault system. While most cause little or no damage, scientists warn that a very large quake – magnitude 7 or greater – is expected in the coming decades on one of California’s major fault lines.
Friday’s quake follows a magnitude 5.7 temblor that shook Hawaii’s Big Island earlier in the day. Despite occurring on the same day, the two quakes were unrelated geologically. The Hawaii quake was centered on the southern flank of Kilauea volcano and caused strong shaking on the Big Island. Light shaking was felt widely across the other Hawaiian islands including Oahu and Maui.
In summary, a light but widely felt earthquake centered near Malibu provided a short shake for Southern Californians on Friday afternoon. The quake caused no major damage but was an important reminder to check emergency preparedness kits and secure items that could injure someone or cause property damage in a larger quake. While small quakes are common in the seismically active region, residents are urged to take steps to protect themselves for the possibility of a damaging earthquake. Seismologists monitor dozens of faults capable of producing large, destructive temblors in the future.
