Pennsylvania environmental regulators want to determine whether a series of minor earthquakes in the state this week were caused by nearby fracking operations by an oil and gas company. Five tiny temblors, all too weak to be felt by humans, took place in a 22-hour span in Lawrence County, about 50 miles north of Pittsburgh and three-quarters of a mile from a natural gas well owned by Houston-based Hilcorp Energy Co. No damage was reported. Hydraulic fracking, a type of drilling method to extract gas or oil from underground shale, has been tied to earthquakes in neighboring Ohio and other states, but never in Pennsylvania, the nation’s No. 2 natural gas-producing state. The state Department of Environmental Protection is consulting with seismologists and plans to meet with Hilcorp “for them to present geologic data they have collected in the area during and prior to drilling and stimulation,” DEP spokesman […]