A 6.5 magnitude quake struck off the coast of Northern California early Thursday, about 100 miles west of Ferndale, the U.S. Geological Survey reported.
No tsunami warning has been issued and no damages have been reported. The quake struck at 6:49 a.m. and at a depth of 7.5 miles.
People in the affected region live in homes that are highly resistant to earthquake shaking, though there are some vulnerable structures, USGS said.