Fracking is a technique used to release gas and oil from shale rock.
- It involves drilling down before fracturing layers of rock using a pressurised liquid.
- Water, sand and chemicals injected into the rock then allow gas to be released.
- The process enables petroleum, natural gas and other substances to be extracted.
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There will be long clear spells tonight, which will lead to a cold night for all.
Wales midfielder Joe Ledley has angrily denied accusations that he laughed at Seamus Coleman's horror injury in Dublin.
A dry, sunny and warm afternoon.