Scientists have been aware of the natural gas in sedimentary rocks of the Appalachian Basin for over 150
years. Fredonia, NY began to run gas-powered streetlights and to power local establishments in town as early as
1825. Geographically, the Marcellus Shale gas basin is the largest in the U.S. However, because of the lower
permeability and porosity of the Marcellus, the natural gas has been impossible to extract in
commercial quantities with conventional technology. For this reason, it was not considered a potential source
for fossil fuel extraction until recently, and is called an “unconventional” resource.