Shale gas buried underground is estimated to increase recoverable gas in the world by 50%. Shale oil would allow oil reserves to expand by 10%. The US Energy Information Administration changed its estimates after a new study where it took into account twice as many oil and gas fields than in 2011.
Contrary to popular belief, this is not North America but South America which has the largest shale gas reserves thanks to Argentina (second global potential with 22,700 billion m3 of technically recoverable reserves). Asia is the second richest shale gas continent, thanks to China, the world champion (31 600 billion m3).
Africa is the third continent in terms of reserves, in front of North America and Europe. Algeria is the major player with the third global potential shale gas reserves (20,000 billion m3): Sonatrach plans soon a first well whereas Statoil and Repsol are still at the survey stage. South Africa is thought to have third global potential shale gas reserves (11,000 billion m3). Net importer of gas, Pretoria supports major foreign companies research in the country (Chevron, Chesapeake, Shell and Statoil). Morocco, with much smaller reserves (566 billion m3) has already one drilling project, with help of Irish and Canadian companies. Tunisia also has shale gas resources (651 billion m3), but focuses primarily on conventional hydrocarbons. As for shale oil, the largest player in Africa is Libya with the fifth potential in the world.
In North America, the reserves of shale oil in the United States have been revised upwards.
Finally, Europe has the largest potential shale oil in the world in Russia (75 billion barrels), but it comes last in terms of shale gas potential, despite the Russian (8,000 billion m3), Polish (4200 billion m3), and French reserves (3900 billion m3). Apart from Poland, where drilling is well underway, it is in countries with little potential as Romania (1415 billion m3), Denmark (906 billion m3), the UK (736 billion m3), Sweden (283 billion m3) and Spain (227 billion m3), that research is most advanced.