Earthquake hits San Francisco, shaking Berkeley awake

San Francisco Bay area residents have been shaken awake by a 4.5-magnitude earthquake, which hit the region in the early hours of Thursday.

The US Geological Survey (USGS) said the quake's epicenter was two miles from Berkeley, California. The earthquake had a preliminary depth of eight miles.

No damage or injuries was immediately recorded, but supermarket produce was shaken from its shelves and ceiling panels knocked loose.

The quake hit at 2:39am local time, and the USGS website said that people reported feeling the quake 40 miles south, in San Jose. 

"Felt like a big truck drove into the building or something blew up downstairs. It just rocked the room and bed like two or three times quickly with a decently loud rumble in North Berkeley," Dale Fest wrote on the San Francisco Chronicle's Facebook page .

Jack Boatwright, a geophysicist with the USGS Earthquake Science Center in Menlo Park, said the shaking from the quake "seemed a little weak, about half as strong as what you would expect."

He told the Chronicle that by 4:15 a.m., there had been no aftershocks, which he called "a good sign. It may mean less likelihood of a larger earthquake to follow."

San Francisco sits on the San Andreas Fault, a continental transform fault that extends roughly 750 miles through California. It forms the tectonic boundary between the Pacific Plate and the North American Plate.

The quake was on the Hayward Fault, part of the San Andreas Fault.

The Hayward Fault is capable of producing a 7-magnitude fault, which would have caused significantly more damage.

 Its last major earthquake was a 6.8-magnitude quake, which occurred on October 21st, 1868, destroying downtown Hayward and killing five people, injuring 30.

It was considered the "Great Earthquake" until 1906, when San Francisco was hit by its last major quake, which killed 700 people.

The region is considered overdue for another quake, given they usually occur every 140 years.