A preliminary 4.1 magnitude earthquake struck Thursday morning near Bay Point, according to the United States Geological Survey.
The quake, centered about 3.6 miles northwest of Bay Point and about 6.2 miles northwest of Pittsburg, hit at 5:07 a.m., the USGS said.
Many in the Bay Area felt the shaking, from as far north as Fairfield to as far west as Half Moon Bay to as far south as San Jose.
The quake's origin was on the Concord-Green Valley Fault, and it had a depth of nearly 12 miles, according to USGS data.
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No other information was immediately available. Updates to come.