BBC: Shale gas estimate in North West 'bigger' than previously thought
Estimates of Cuadrilla's shale gas resource in the North West of England may have to be increased significantly upwards.
A geologist with the company said there is 330 trillion cubic feet (tcf) of gas in place in its licence area, 50% more than previous estimates.
Cuadrilla is the only company in the UK to have used hydraulic fracturing (fracking) in its test wells. But it could take two years to see if the gas is commercially viable.
Last summer the British Geological Survey (BGS) reported that there could be around 1,300 tcf of gas in the Bowland basin in North West England.