Tuesday, April 15th, 2008 — California has more than a 99 percent chance of having a magnitude 6.7 or larger earthquake within the next 30 years, according scientists with the U.S. Geological Survey. The scientists came to their conclusion after using a new model that comprehensively combines information from seismology, earthquake geology, and geodesy (measuring precise locations on the Earth’s surface) to determine the probability of big quakes.