Pennsylvania has seen a boom in natural gas production due to shale gas.

Pennsylvania has experienced a significant boom in natural gas production due to the development of shale gas, particularly from the Marcellus Shale formation. This region, located in the Appalachian Basin, contains vast reserves of natural gas that have become accessible through hydraulic fracturing (fracking) and horizontal drilling technologies. The Marcellus Shale has turned Pennsylvania into one of the top natural gas producers in the U.S., with its output contributing substantially to the nation's energy supply. This boom has led to economic growth in the state, including job creation and lower energy costs, though it has also raised environmental and regulatory concerns.