The North American Shale Resource: Characterization of Spatial and Temporal Variation in Productivity

Between 2005 and 2012, U.S. natural gas production from ultra-low permeability hydrocarbon-prone mud rock formations, often referred to as the “shale resource” [1], increased 20-fold to more than \(570\,\mathrm{{Mm}}^{3}\) per day, and now accounts for \({\approx }{33}\,\%\) of total U.S. gas output. These developments have had a profound impact on the U.S. energy sector.