Magnitude 3.8 earthquake shakes Malibu, LA's Westside

LOS ANGELES — A magnitude 3.8 earthquake brought weak shaking to Malibu and Los Angeles’ Westside Friday.

The epicenter was about 4.6 miles north of Point Dume, in the mountains above Malibu’s city limits. It’s the seventh earthquake so far this year to rumble in this area.

According to the U.S. Geological Survey, “weak” shaking — or Level 3 as defined by the Modified Mercalli Intensity Scale — may have been felt in Malibu, Thousand Oaks, Calabasas, Woodland Hills, Canoga Park, Winnetka and Reseda.

Shaking of that intensity is generally quite noticeable indoors, especially on upper floors, and can cause idled vehicles to rock slightly.

Weak shaking considered Level 2 on the Modified Mercalli Intensity Scale may have been felt across the rest of the San Fernando Valley, Santa Monica and across the Los Angeles Basin. That intensity of shaking is felt by only a few people at rest, especially on an upper floor of a building.

In Mar Vista, shaking could be felt for 10 to 15 seconds on the second floor of a building, feeling as if someone had kicked a desk and made it wobble.

Friday’s epicenter was about three-fifths of a mile northeast of a considerably larger, magnitude 4.7 earthquake that struck on Sept. 12. That quake was powerful enough to send Malibu’s mayor and his wife diving under their kitchen table, and startled anchors broadcasting live at KABC-TV and KTTV-TV.

Friday’s epicenter was also about six miles northeast of a magnitude 4.6 earthquake that struck on Feb. 9, with an epicenter within Malibu’s city limits. That earthquake reportedly was strong enough to toss items off a counter and cause a wall to crack.

By seismologist Lucy Jones’ count, Southern California has experienced 15 independent seismic sequences so far this year in which there have been at least one magnitude 4 or higher earthquake. That’s the highest annual total in the last 65 years, surpassing the 13 seen in 1988.

The active seismic year, however, doesn’t provide a clue as to when Los Angeles County’s next major, damaging earthquake will strike. L.A. County’s last such quake was 30 years ago, when a magnitude 6.7 earthquake centered in the San Fernando Valley caused at least 57 deaths and left more than 7,000 injured, about 20,000 homeless and more than 40,000 buildings damaged.

Southern California’s last megaquake occurred in 1857, when an earthquake with a magnitude of around 7.8 ruptured about 225 miles of the San Andreas fault between Monterey County and San Bernardino County.