Pa. officials trying to determine if small earthquakes are linked to hydraulic fracturing

The Pennsylvania Department of Environmental Protection and the Department of Conservation and Natural Resources are conducting a study to see if a series of small earthquakes recorded Monday in Western Pennsylvania are linked to a nearby natural gas hydraulic fracturing operation, Laura Legere reports for the Pittsburgh Post-Gazette.

"The U.S. Geological Survey says five minor earthquakes originated in an area just west of New Castle in a 22-hour period on Monday, all small tremors between magnitude 1.7 and 1.9, which is below what humans can feel," Legere writes. "The timing and proximity of the Lawrence County earthquakes—originally the geological survey had identified just two—suggest a link to a nearby natural-gas fracking operation, but seismologists were being cautious Thursday, saying it is too early to tell definitively if fracking triggered the quakes." (Post graphic)

"A DEP spokeswoman said Wednesday that the wells that were being fracked have horizontal wellbores headed northwest from the pad, which is the general direction of the closest earthquake," Legere writes. Michael Brudzinski, a geology professor at Miami University in Ohio, told Legere, "I think anyone looking at the situation would say there are earthquakes very close to where the well is at the time the well is being stimulated with hydraulic fracturing. That’s suggestive that there is a link. But I don’t think any of us are ready to say anything more conclusive than that.” Injection wells for disposal of fracking fluids have caused quakes in Oklahoma, officials there say.