Earthquakes cannot be predicted like the weather but those at the Southern California Earthquake Center are using all the information they can to study the complex fault systems beneath us.
"The San Andreas Fault is very active geologically speaking but its been awhile since we've had a big earthquake on the Southern San Andreas," noted Tom Jordan, SCEC Director.
In 1857, a magnitude 7.8 earthquake ruptured from Central California down to the Cajon Pass, but it was between 1680-1715 that the last major break occurred in the Coachella Valley. That's over 300 years, about 150 years overdue.
Christine Goulet, the Special Projects Director at SCEC commented, "For example, for L.A. we care more about a smaller fault that is right under the city but for you guys where you're at, these big events on [the] San Andreas or San Jacinto faults can have a big impact."
"It [the San Andreas] is one of the great faults of the world. It's a boundary between the North American plate and the Pacific plate and where we in California get our biggest earthquakes," Jordan continued, "the faults are stuck so the ground gets stretched and that stretching stores energy, elastic energy like pulling on a rubber band and eventually you get to the point where the rubber band breaks and that's when you get an earthquake".
One misconception is that when small earthquakes occur, like the swarms that have been occurring near the Salton Sea, they are relieving stress. In reality, they are so small relative to the big one, they don't do much in terms of releasing the energy that's stored up in the fault system. "So basically in order to release that energy we have to have big earthquakes so that's why we say large earthquakes are inevitable here in California," Jordan stated.
"Everything in the Coachella Valley will be lifted up, moved and shaken around in ways that have not been experienced in modern times," explained Mark Benthien, SCEC Director for Communication, Education and Outreach.