Magnitude 4 earthquake near Oxnard shakes up L.A. and Ventura counties

A magnitude 4 earthquake that ruptured in the Pacific Ocean sent weak shaking into Ventura County and across the Westside, San Fernando Valley and South Bay areas of Los Angeles County.

The earthquake hit at 2:13 a.m. Thursday about 19 miles south of Oxnard and about 15 miles southwest of Naval Base Ventura County at Point Mugu.

Malibu’s Point Dume is about 25 miles northeast of the epicenter, and Santa Monica is about 40 miles east of the earthquake’s origin. Downtown L.A. is almost 55 miles away from the epicenter.

There were no reports of damage in Oxnard, the Police Department said, where a dispatcher felt a bit of shaking.

The earthquake occurred in an area of a number of mapped faults, such as the Anacapa-Dume fault, which runs underneath the Pacific Ocean parallel to the coastline of Malibu and eventually heads east into Santa Monica.

The Anacapa-Dume fault is part of the Transverse Ranges Southern Boundary fault system, which stretches for about 125 miles in a west-to-east direction. Other faults in the same system include the Santa Monica, Hollywood, Raymond, Malibu Coast, Santa Cruz Island, and Santa Rosa Island faults, according to the Southern California Earthquake Center.

The magnitude 4 earthquake came three hours after a magnitude 3.9 earthquake ruptured near San Jose, sending light shaking to Morgan Hill and Gilroy, according to the USGS, and weak shaking around the San Francisco Bay Area, as well as the Monterey, Santa Cruz and Salinas areas.

In the last 10 days, there have been three earthquakes of magnitude 3.0 or greater centered near the epicenter of Thursday morning’s earthquake.

An average of 234 earthquakes with magnitudes between 3.0 and 4.0 occur per year in California and Nevada, according to a recent three-year data sample.

The earthquake occurred at a depth of 6.2 miles. Did you feel this earthquake? Consider reporting what you felt to the USGS.

Even if you didn’t feel this small earthquake, you never know when the Big One is going to strike. Ready yourself by following our five-step earthquake preparedness guide and building your own emergency kit.

The first version of this story was automatically generated by Quakebot, a computer application that monitors the latest earthquakes detected by the USGS. A Times editor reviewed the post before it was published. It was subsequently updated by a Times reporter. If you’re interested in learning more about the system, visit our list of frequently asked questions.