Southern California Overdue for Big Quake Landmark study expects one along San Andreas fault By John Johnson, Newser Staff Posted Aug 20, 2010 3:50 PM CDT 17 comments Comments Movement along the infamous San Andreas Fault during big earthquakes has turned Wallace Creek into a 'Z' shape. (Getty Images) (Newser) – Is the Big One imminent? A major new study lends weight to the "yes" camp, asserting that Southern California is overdue for a massive earthquake, reports the Los Angeles Times. Researchers studied the San Andreas fault and found that it's produced far more major quakes than previously thought—as often as every 45 to 144 years—over the last 7 centuries. And since the last big one was in 1857 ... "There are storm clouds gathered on the horizon," says one researcher. "Does that mean it's definitely going to rain? No, but when you have that many clouds, you think, 'I'm going to take my umbrella with me today.' That's what this research does: It gives us a chance to prepare."