The earthquake happened at 5:07a.m. in the waters off Wheeler Island in Suisun Bay, according to the National Weather Service.
The quake was centered 3.6 miles north of Bay Point and 6.2 miles northwest of Pittsburg at a depth of 12 miles, according to USGS.
RELATED: VIDEO: What to pack in your earthquake emergency kit
What to pack in your earthquake emergency kit
It was felt in other parts of the Bay Area including the North Bay and San Francisco, and even Sacramento.
BART is telling passengers to expect systemwide delays of about 20 minutes as trains are running at reduced speeds while employees inspect the train tracks.
No injuries have been reported.
Click here for the latest stories and videos about earthquakes here in the Bay Area and around the world, and click here for more information on disaster preparedness.
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