COBB (CBS SF) — A preliminary magnitude 3.3 earthquake struck in the mountains west of Cobb in the North Bay on Monday night, according to the U.S. Geological Service’s earthquake map.

The epicenter of the quake (USGS Interactive Map)

The tremor struck at around 10:33 p.m. The epicenter was about 2.5 miles west of Cobb, between Geyserville and Middletown, in the Mayacama Mountains on the Sonoma and Mendocino County line.

No other details were immediately available.