A 4.3 magnitude earthquake shook part of the San Francisco Bay area yesterday. No reports of damage have been reported. The quake epicenter was 9 miles south or Brentwood, a part of the aftershocks from the swarm of earthquakes that have been centered in the Mojave Desert on the San Aranedas Fault.A The question all officials have is: a Is this the big one?a This is a busy time for earthquakes, an all media rea monitoring!