The North York Moors, the Peak District and the Yorkshire Dales are all suitable for fracking according to a new report.
Scientists from Durham University's Department of Earth Sciences have reviewed existing data for each of our 15 national parks and found only four where it could be considered.
The briefing document found the four parks with geology to interest companies looking to exploit shale gas, shale oil or coalbed methane were the North York Moors, the Peak District, the South Downs and the Yorkshire Dales.
Fracking was considered "unlikely" in the Brecon Beacons, Exmoor, New Forest and Northumberland. They have shales or coals present but other aspects of their geology make fracking unfavourable.
The remaining seven national parks - the Broads, Cairngorms, Dartmoor, Lake District, Loch Lomond and the Trossachs, Pembrokeshire Coast and Snowdonia - have geology which rules out fracking, the report found.
Those behind the study, published today, said they produced the report as, they claimed, there remained uncertainty about the policy on fracking in national parks.
Dr Liam Herringshaw, of Durham University's Department of Earth Sciences, said: "The geology of the UK is well-known, so we can examine which national parks are potential targets for fracking, and which national parks can be ruled out.
"Some national parks have no shales or coal within them or adjacent to them, so are of no interest to fracking companies. Many other national parks do contain shales or coal, but their nature means that they are unlikely to yield economic quantities of oil or gas.
"We hope that this review of existing information about the geology of the UK's national parks will help provide all sides involved in the fracking debate with some clarity about the potential for fracking in these areas, which currently appears to be lacking."
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