A very clever new study concludes that oil and gas exploration, especially fracking and the injection of the liquids used for it back into deep wells, is the cause of an increase in both the frequency and severity of earthquakes in the state of Texas.
To collect seismic reflection data, an artificially generated wave ripples through the ground and reflects back to the surface, like light off a mirror. The result is “a little bit like an ultrasound,” Magnani said, revealing not baby toes but twisted rock.
The scientists compared the Texas earth with Mississippi, another seismically active region that, like Texas, is not close to a turbulent edge of a tectonic plate. Unlike Texas, though, north Mississippi has a much longer history of recorded earthquakes, going back to the early 1800s.An underground ultrasound revealed that, beneath Texas, the most recent signs of active faults were in a geologic layer 300 million years old — 70 million years before the first dinosaur took its first step. All the younger layers above it were stable.
“All the displacement was stopping at a layer that is 300 million years old,” Magnani said. “The fault did not move after that layer was deposited.”
In the Mississippi region, in contrast, the rock told a story of continuous fault activity, unbroken for the last 65 million years.
Given the lack of faults in Texas’s most recent 300 million years of history, there is no known geologic process that could explain its sudden quake outbreak. “There is no other explanation” except that these earthquakes are caused by human activity, Magnani said.
Combine that with the clear correlation between increased earthquake activity in areas where fracking is most heavy and you have a compelling case that fracking is the primary cause of all this new tectonic activity. Then combine that with the routine problems with fracking liquid leaching into ground and surface waters and with the sheer volume of fresh water required — water that can’t be reclaimed or reused — and you have a compelling case for phasing out the practice entirely and moving to renewable energy sources.