5.1 Earthquake Rattles Northern California Coast

A magnitude 5.1 earthquake struck off the coast of Northern California early Wednesday morning, according to the U.S. Geological Survey (USGS).

The quake occurred at approximately 5:45 a.m., about 40 miles west of Petrolia, and was followed by a magnitude 4.5 aftershock at 6:11 a.m. off the coast of Ferndale.

A third tremor, a magnitude 3.8, was recorded around 8:50 a.m. The Redwood Coast Tsunami Work Group reported a busy morning for North Coast earthquakes, noting that some residents in Del Norte County received a ShakeAlert notification before 4 a.m.

for a magnitude 5.7 earthquake offshore of the California-Oregon border. The main 5.1 quake was felt lightly from Westport in Mendocino County to Blue Lake, with early reports coming from Arcata and Ferndale.

The USGS ShakeAlert system issued warnings urging residents to "Drop, cover and hold on" if shaking intensified. No tsunami warnings were issued, and no significant damage has been reported.