The magnitude 4.0 temblor was centered near Alamo, Calif., about 10 miles underground, and was felt in Contra Costa and Alameda counties, the San Francisco Chronicle reported.

David Oppenheimer, a seismologist with the U.S. Geological Survey, told the newspaper the quake happened in an unnamed fault more than two miles from the larger Calaveras fault. The last time a quake was centered there was in 1990, when a cluster of quakes caused minor structural damage to some homes, he said.