Just IMO, but the two canonical books for this subject are "Cadillac Desert" and "The Prize". The "gas in the water" stories are significantly contaminated by

Just IMO, but the two canonical books for this subject are "Cadillac Desert" and "The Prize". The "gas in the water" stories are significantly contaminated by very bad propaganda. It's possible that they are true - that they are caused by fracking - but it's not likely. The depths are pretty radically different. Pennsylvania in particular is where Drake found oil oozing to the surface, so ... who knows what's down there, close to the surface? I know I am no geologist and even a good geologist may not have good understanding of that region.