EcoWatch: Two earthquakes registering at a 4.5 and a 4.4 magnitude shook frack-happy Oklahoma on Saturday, some of the strongest felt in the state this year. The stronger quake occurred just a few miles from the city of Cushing, which holds one of the largest crude oil storage facilities in the world. The recent quakes struck only a handful of weeks after the Oklahoma Corporation Commission (OCC), the states public utilities commission, shut down several disposal wells around Cushing and issued new regulations...