The 3.7-magnitude earthquake was reported at 3:59 a.m., according to the US Geological Survey.
The quake, which occurred at a depth of 1.7 miles, was centered two miles northeast of The Geysers, four miles west southwest of Cobb and six miles west northwest of Anderson Springs, the US Geological Survey reported.
Ten smaller earthquakes followed within the hour – most of them at or near the epicenter of the 3.7-magnitude quake – with the largest measuring 2.5 on the Richter scale, according to monitoring records.
Shake reports were made to the US Geological Survey from Hidden Valley Lake, Middletown and Sebastopol, as well as more faraway locales including Sacramento, Martinez, San Francisco and Menlo Lake.
The Geysers area last experienced a quake measuring 3.0 or above on Oct. 30, when a 3.6-magnitude quake occurred there, as Lake County News has reported.
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