HOW FRACKING HAS FUELED AMERICA'S INSATIABLE APPETITE FOR OIL AND GAS
With its voracious appetite for energy and a desire to be less reliant on imports, the U.S. became the first country to exploit the potential of fracking.
The process - shorthand for hydraulic fracturing - involves creating little explosions underground, then injecting water and chemicals to release gas and oil trapped in cavities in shale rocks.
In 1996, the U.S. produced just 0.3trillion cubic feet of shale gas.
By 2011, however, that figure had leapt to 7.8trillion, allowing America to transform itself from an importer to a net exporter of gas.
But the abundant supplies of gas have outpaced development of infrastructure around oil plants.
And with gas prices having dropped from their 2008 peak of more than $13 per million British thermal units to just $3.40 it is now uneconomic to build pipelines and storage tanks.
As a result, much of the gas is burned off instead.
Shale gas reserves are plentiful and widespread across much of the world, but until developments in fracking it has been largely inaccessible.
In China, explorable shale reserves are estimated at 86trillion cubic feet, enough to supply the nation's needs for two centuries
Liquid gold: Graphic showing how U.S. oil production outrip that of Saudi Arabia
Adam Brandt, a Stanford academic who studies greenhouse gas emissions from fossil fuels, told the FT: 'The situation in the shale oilfields is similar to the early days of the US oil industry.