The process involves pumping water containing small percentages of other materials into the porous shale under pressure to hydraulically fracture it and release the trapped oil and gas.
Increasing external pressure this year could fracture the Iranian leadership on this issue, but no one has adduced any convincing evidence that is happening.
This year he completed what is believed to be the first ever fracture stimulation procedure in Turkey: injecting a mixture of water and sand at high pressure down the wells to break up rock and release gas.
Fracking involves the injection of water containing a surfactant and various other chemicals under high pressure into a source rock e.g. shale, causing the latter to fracture and release natural gas (principally methane).