Shale Gas is methane (natural gas) which is trapped in impermeable shale rock deep underground, unlike conventional natural gas which is trapped in permeable rocks, such as sandstone. The gas cannot flow through the shale, so simply drilling a well, as you would for conventional natural gas, is not enough. The shale rock must be cracked to free the gas, hence the need for hydraulic fracturing (fracking). For the same reason it is necessary to drill large numbers of wells at regular intervals. To produce as much gas as a conventional gas field with a dozen or so wells, would require hundreds or thousands of shale gas wells.
Because of the much more intense nature of the shale gas extraction process it is associated with much more negative impacts than conventional drilling. These include leaking methane, water contamination, air pollution, radioactive contamination, massive industrialisation of the landscape, worsening climate change and earthquakes. Severe health effects in people and animals are beginning to mount areas where shale gas extraction is widespread. Shale gas extraction also leaks large amounts of methane (a very strong greenhouse gas) and makes available fossil fuels that would not otherwise be burnt, both significantly worsening climate change.
Cheshire Shale Potential
Six of the Cheshire licences – PEDLs 147, 185, 186, 187 and 189 have been identified to contain shale potential.
British Geological Survey
This short film that shows how the British Geological Survey have mapped (using computer software) and estimated the amount of Shale in the Northern parts of the UK.