Drilling for oil and gas brings up a lot of water. If operators don’t reuse it for something else, they often pump it back down into the ground. The water goes down in what are called injection wells-- and new research shows they can definitely cause earthquakes, at least in Oklahoma. Geology Professor Shemin Ge is with the University of Colorado at Boulder. She worked on the study, and spoke with APR’s Elise Thatcher. Ge says it took different kinds of scientists working together to figure out what’s going on.