A magnitude 4.7 earthquake struck the south San Francisco Bay area early Thursday morning, but there were no reports of injuries or damage, authorities said.

The quake struck at 5:24 a.m. PDT about 6 miles east of San Martin, a town of 4,200 people in a rural part of southern Santa Clara county, and was followed by seven smaller aftershocks, according to the U.S. Geological Survey.

Click here for FOXNews.com's Natural Disaster section.

The quake could be felt in San Francisco, about 70 miles north of the epicenter.

No one was hurt and there were no reports of damage, according to the Santa Clara County sheriff's department and police in Gilroy, about 8 miles from where the quake struck.