Residents around Eagle Mountain Lake outside of Fort Worth have had a shaky few months. Dozens of small earthquakes have struck the area out of the blue. The Dallas-Fort Worth area is not known as a place that’s prone to earthquakes. In fact, before 2007, there were no recorded earthquakes in the area. Since then, there have been hundreds. Studies of other swarms of earthquakes to the south in Johnson County and around the Dallas-Fort Worth airport have shown disposal wells to be the culprit, where wastewater from oil and gas drilling is injected deep underground. Inject enough wastewater, at the right pressure, and it can cause quiet faults to slip, resulting in earthquakes.