| Natural gas is a growing segment of American energy demand; accounting for approximately 23% of primary energy generation in 2008 when approximately 273 quadrillion British Thermal Units (BTUs) of energy were developed from natural gas. Unconventional gas reservoirs such as coal bed methane, tight sands and gas shales account for an ever increasing percent of natural gas reserves, with estimates of up to 60% of the current onshore technically recoverable gas coming from these unconventional reservoirs. Shale gas production has grown from approximately 2.4% of the onshore production of natural gas in 1990 to almost 17% of the total onshore natural gas production in 2008 and is predicted to grow to nearly 30% of the total onshore natural gas production by 2025. Development of shale gas plays has been expanding since the development of the Barnett Shale in the 2000s to other plays including the Fayetteville Shale in Arkansas, the Haynesville Shale in Louisiana and Texas, the Eagleford Shale in west Texas, the Woodford Shale in Oklahoma, and the Marcellus Shale in the Appalachians. The potential for shale gas within the U.S. extends far beyond these plays with shales that may have natural gas potential present throughout much of lower 48 states. The widespread occurrence of shales means development could act to supply natural gas resources on a local level with excess gas sold out of the area to supply other markets. While shales have long been known to be source rocks containing large quantities of natural gas, it was not until industry experimented with drilling horizontal wells and high volume hydraulic fracturing (HVHF) techniques in the Barnett Shale in the 1990s that the potential of shales as a production reservoir was realized. While horizontal drilling and HVHF made shale gas development technically possible it was the combination of these two technologies with increasing natural gas prices during the mid-2000s that made the Barnett an economic success and the model for future shale gas development in the U.S. Since the success in the Barnett, these technologies have been adapted to develop shales across the U.S. and Canada, and are growing worldwide. Domestically, the potential shale gas plays to be developed range in geologic age from the Cambrian-aged Conasauga Shale in Alabama to the Eocene-aged Green River Shale in Utah and Colorado. However, most of the shale plays are either from the Devonian to Pennsylvanian Periods or from the Jurassic to Cretaceous Periods. The active shale plays in the U.S. are predominantly formed during the Devonian and Mississippian Periods, with the exception of the Jurassic Haynesville and Upper Cretaceous Eagle Ford shale. Shale gas wells require millions of gallons of water to perform the horizontal drilling and HVHF necessary to produce the natural gas from the formation. The low permeability of shales requires the large wellbore area of a horizontal well and the increased permeability that results from HVHF to produce economic quantities of natural gas. Because of this low-permeability nature of shales, shale gas development is also considered a resource play where large areas need to be developed to generate economic quantities of gas. As such, issues related to water management such as water sourcing and disposal of produced water create challenges that vary from area to area. Where available, a link is provided for additional information on a treatment technology or vendors. The treatment technology link opens up a Fact Sheet and the vendor link is to a page that provides a profile on their technology, as well as the vendor’s website. ![]() Click Here to continue to the Shale Gas Water Treatment Catalog or use the menu on the left. |