U.S. Geological Survey seismologist Susan Hough accompanied The Associated Press to an advance screening of the film. Despite the implausible plot, she said the San Andreas will indeed break again, and without warning. "We are at some point going to face a big earthquake," she said. The San Andreas is notorious for producing big ones, but a magnitude-9 or larger is virtually impossible because the fault is not long or deep enough, Hough noted. The most powerful temblors in recorded history have struck along offshore subduction zones where one massive tectonic plate dives beneath another. The 1960 magnitude-9.5 quake off...