EIA is currently in the process of updating maps of major tight oil and shale gas plays , including the Eagle Ford and Marcellus plays, which will help to better characterize the geology of key areas of production in the United States. EIA’s most recent maps focus on shale and tight oil plays, and characterize plays based on geologic characteristics, including rock type and age. Understanding geologic history and processes helps exploration and production companies reduce the risk of drilling dry, nonproducing wells and better understand hydrocarbon resource potentials. Production of crude oil and natural gas occurs in two classes of rock: source rocks and reservoir rocks. Source rocks are sedimentary rocks in which hydrocarbons (organic chemical compounds of hydrogen and carbon) form. Reservoir rocks are both porous, meaning that there are open […]