The map below shows "spud" (initial drilling) dates for conventional and unconventional oil and gas wells in Pennsylvania from 2000 through August 2016. The somewhat wordy definition of "unconventional" (which includes but is not limited to "fracking") is given at the data source, here.
The time animation format of the map reveals the shift from conventional to unconventional wells around 2008 followed by the drop-off in new drilling with the recent collapse in energy prices in a way that even a series of static maps would fail to capture.