Natural gas reserves in United States

Underground Reservoirs Hold Oil and Gas

A "reservoir" is a place where large volumes of methane, the major component of natural gas, can be trapped in the subsurface of the Earth at places where the right geological conditions occurred at the right times.

Reservoirs are made up of porous and permeable rocks that can hold significant amounts of oil and gas within their pore spaces.

What Are Proved Reserves?

Proved reserves of natural gas are estimated quantities that analyses of geological and engineering data have demonstrated to be economically recoverable in future years from known reservoirs.

Proved reserves are added each year with successful exploratory wells and as more is learned about fields where current wells are producing. For this reason those reserves constantly change and should not be considered a finite amount of resources available. Application of new technologies can convert categories of previously uneconomic natural gas resources into proved reserves. U.S. proved reserves of natural gas have increased in every year since 1999, a trend accelerated by shale gas drilling.

How Much Natural Gas Reserves Are in the United States?

In 2010, U.S. natural gas proved reserves, estimated as "wet" gas which includes natural gas plant liquids, increased by 12% to 318 trillion cubic feet (Tcf). Major improvements in shale gas exploration and production technologies drove the increase in U.S. natural gas proved reserves.

What Are Undiscovered Technically Recoverable Resources?

In addition to proved natural gas reserves, there are large volumes of natural gas classified as undiscovered technically recoverable resources. Undiscovered technically recoverable resources are expected to exist because the geologic settings are favorable despite the relative uncertainty of their specific location. Undiscovered technically recoverable resources are also assumed to be producible over some time period using existing recovery technology.

Did You Know?

In 1821, William Hart dug the first well specifically to produce natural gas in the United States in the Village of Fredonia on the banks of Canadaway Creek in Chautauqua County, New York. It was 27 feet deep, excavated with shovels by hand, and its gas pipeline was hollowed-out logs sealed with tar and rags.