Could the torrents of rain that have recently soaked California trigger an earthquake? The science is mixed. Heavy rainfall can spark earthquakes, according to one scientist, and with a winter marked by moisture-packed storms, California should be prepared. “If water enters a fault, especially under high pressure, it lubricates the fault and can push it open and make it easier for it to move, causing an earthquake,” said Gillian Foulger, a professor of geophysics at Durham University in the United Kingdom.