An abundance of natural gas is buried across North America, contained within huge shale deposits spanning thousands of square miles across numerous states. Geologists had long known that this gas was locked away, and now, a combination of new and long-proven technologies has opened the door to extracting and producing this natural gas for the world market.

Though some of these deposits, called shale plays, are located in traditional energy-producing states, such as Texas, new plays have been discovered in other regions throughout the country. The Marcellus Shale Play, for example, stretches across parts of New York, Pennsylvania, Ohio, Maryland, Virginia and West Virginia. While the discussion of shale plays often focuses on 12 major sites, more continue to be discovered.

New Discoveries

Over the past four to five years, new discoveries and increased shale gas development activity – particularly around the Barnett and Eagle Ford gas-fields in Texas, Haynesville in Louisiana, and Marcellus in the mid-Atlantic States – have greatly increased the volume of U.S. natural gas resources that can be produced with known technologies.

The U.S. Department of Energy estimated total U.S. natural gas reserves and resources to be approximately 1,200 TCF in 2000. In less than a decade, this same estimate more than doubled to over 2,500 TCF in 2009. At current consumption levels, this resource base represents over a century of supply. The majority of the increase is due to the increased potential of shale gas. Shale gas resource estimates in 2009 were over 800 TCF, up from only 55 TCF in 2000.

According to the Energy Information Administration, from 2000 to 2005, shale gas production in the United States increased by 13.5 percent annually and by 46 percent annually from 2005 to 2010. By 2025, production is expected to double from today's 14 billion cubic feet per day and will represent nearly half of total U.S. supply by 2035.