TIME: Sizing Up the Quakes That Come from Hydraulic Fracturing

We already know that hydraulic fracturing—the process of injecting millions of gallons of water and chemicals deep into the earth to exploit the natural gas trapped inside rock—can likely help cause earthquakes.

The British energy company Cuadrilla Resources admitted earlier this year that fracking operations caused a series of small quakes in Lancashire, and scientists have raised concerns about an unusual number and strength of quakes that hit this fall in Oklahoma, a state that has long embraced fracking.

Environmentalists are already worried about the risk of water contamination and air pollution from fracking and shale gas drilling—do we need to fear quakes as well?  HERE