Lake County's Cobb Mountain community was shaken awake early Thursday morning by a magnitude 4.6 earthquake that startled even folks accustomed to seismic activity because of its size.
While shakers around magnitude 2 and 3 are common to the area, Thursday's 2:09 a.m. jolt lasted longer and proved stronger than usual, residents said.
"It lasted a really long time. You could tell" it was larger, said Hardester's Market clerk Alicia Mullin.
"It was pretty significant," said Bonnie Evans at the Texaco station in town, where cigarettes, canned soups and a couple of bottles in the walk-in fridge had been knocked to the ground.
The U.S. Geological Survey reported that the quake was centered about 3 miles southwest of Cobb, in a seismically active area near The Geysers geothermal steamfields.
Residents of Sonoma County felt it, too, including some as far south as Santa Rosa.