Kansas officials have been reluctant to link the mysterious earthquakes in south central Kansas to fracking, but last week they said for the first time the temblors are likely caused by disposal of the waste water that is a byproduct of the oil and gas extraction process. “We can say there is a strong correlation between the disposal of saltwater and the earthquakes,” Rick Miller, geophysicist and senior scientist for the Kansas Geological Survey, told the Journal-World. It’s the first time state officials have so clearly stated the likely cause of the earthquakes, which are afflicting a region where fracking is widely used.