Five moderate-to-strong earthquakes strike in California. Could the cluster of quakes be a harbinger of the Big One? Another earthquake-prone area — New Madrid, near Memphis, Tenn. — has had more than its share of impressive quakes. New data based on years of GPS measurements may give scientists more information.
Michael Ellis, professor of geology, Center for Earthquake Research and Information, the University of Memphis; program director, geomorphology and land use dynamics, National Science Foundation
Ross Stein, geophysicist, U.S. Geological Survey