The Barnett Shale is a geological formation of economic significance. It consists of sedimentary rocks of Mississippian age in the U.S. State of Texas. The formation is estimated to stretch from the city of Dallas west and south, covering 5,000 square miles (13,000 km²) and at least 17 counties.
Directional drilling (sometimes known as slant drilling outside the oil industry) is the science of drilling non-vertical wells. Directional drilling can be broken down into three main groups: Oilfield Directional Drilling, Utility Installation Directional Drilling (commonly known as H.D.D./Horizontal Directional Drilling/Directional boring) and in-seam directional drilling (Coal-Bed methane).
