Pelepko says pressure can also be a factor in inducing earthquakes. Pelepko says this technique enlarges the pressure zone near the wells during hydraulic fracturing, stimulating the release of oil and gas by injecting millions of gallons of water, sand and chemicals into rock formations. “ The greater the vertical separation between this basement rock and the activity, the less likely that an induced event will occur,” Pelepko says.Īt the time of the quakes, Hilcorp was conducting a “zipper” fracture, a technique where two parallel, horizontal wells are fracked in tandem. The DEP’s Seth Pelepko says the wells were drilled about 8,000 feet below the surface and were much closer to the region’s ‘basement’ rock than a typical shale gas well. In a statement, company spokesman Justin Furnace said the company is reviewing the DEP’s report and has no immediate plans to resume work on the well. Hilcorp immediately shut down the well, known as the North Beaver NC Development well, when DEP alerted the company to the seismic activity. In Ohio, a study found that 77 small earthquakes were linked to natural gas drilling around Poland Township in 2014, just over the state line from Lawrence County. In those cases, fracking waste disposal - not the fracking process itself - is usually the cause. In addition, Pelepko says ther were “ no faults identified along portions of the well bore where these seismic events were detected.”Įarthquakes in Pennsylvania are relatively uncommon, though oil and gas-related earthquakes have been observed in Ohio and Oklahoma. “At least within Pennsylvania, this is the first time that we have seen that sort of spatial and temporal correlation with operator activity,” says Seth Pelepko, chief of well-plugging and subsurface activities for DEP’s oil and gas management program. But they were significant, if only because fracking-induced earthquakes had never been recorded in the state. Quakes that small are too faint to be felt on the surface. In April 2016, Texas-based Hilcorp Energy Company was fracking a pair of wells in the Utica Shale near New Castle, Pennsylvania when seismic monitors nearby detected five tremors, measuring between 1.8 and 2.3 on the Richter scale. As a result, the Department of Environmental Protection (DEP) is stepping up its requirements for drilling in that part of the state, which is known for seismic activity. ![]() ![]() Pennsylvania officials say they’ve confirmed the state’s first fracking-related earthquakes took place last year in Lawrence County, northwest of Pittsburgh.
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