The quake was reported at 4:26 a.m., according to the US Geological Survey.
The agency reported that the quake was recorded two miles east southeast of The Geysers, four miles southwest of Cobb and four miles west of Anderson Springs at a depth of 2.7 miles.
The US Geological Survey received 76 shake reports from around California and one from Carson City, Nev.
Kelseyville, Middletown and Hidden Valley Lake residents reported feeling the quake, as did people in Humboldt and Napa counties. The most responses came from Healdsburg, in Sonoma County.
Reports also came from the Bay Area, including San Francisco, and as far away as Turlock and McKinleyville.
The 3.8-quake was followed by 12 smaller quakes – ranging in size from 1.0 to 2.0 in magnitude – in The Geysers and Cobb areas over the rest of the day.
A 3.7-magnitude earthquake was reported in The Geysers area on Nov. 24, as Lake County News has reported.
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