One year ago, sitting at my desk in Philadelphia, I looked up to see the lights above me swinging from the drop ceiling. A low rumble seemed to sound, like thunder. But looking out the window, the sky was cloudless. Was it raining? It took a while before people realized it was an earthquake. Something unheard of on the East Coast. This was my first earthquake. And, jokingly, I said, it must be fracking.
Turns out that the 5.8 magnitude earthquake that shook the eastern seaboard last August 23, was not caused by natural gas and oil production practices. But in the past year, more evidence has emerged to link the two in other areas of the country. Fracking itself, which can create seismic activity, is not the direct culprit. (Although fracking in Blackpool, England was halted after causing small tremors.)
The connection between fracking and earthquakes has to do with the disposal of wastewater. Fracking wastewater is shot at high pressure down a well and deep into the earth. On New Year’s Eve, a deep injection well in Youngstown, Ohio caused a 4.0 magnitude earthquake. Studies in Arkansas and Texas have also linked a spate of quakes to deep injection wells. None of Pennsylvania’s deep injection wells have caused earthquakes. To see a map of where Pennsylvania’s deep injection wells are located, click here.