The Free Press, Mankato, MN

Archive

Man Made Earthquake

Warren Hall is imploded on the campus of Cal State East Bay in Hayward, Calif., on Saturday, Aug. 17, 2013. The former administration building has been vacant for two years after it was declared seismically unsafe. The U.S. Geological Survey scientists had placed more than 600 seismographs in concentric circles within a mile (1.6 kilometers) of the building to pick up the vibrations. They hope the unique experiment will help map out where the ground might shake the most when the big one hits. (AP Photo/Bay Area News Group, Dan Honda)