A magnitude 3.6 earthquake hit near Crockett at lunch time Saturday, according to USGS.
The rumble, which originally registered at 3.7, started at 11:56 a.m. and was reportedly felt in Vallejo, Martinez, Hercules and other areas.
A smaller 2.7 magnitude quake registered at 12:01 p.m. in the same area.
No injures or damage has been reported.
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