'Your readers will be no doubt be delighted to know I can't think of a more unlikely place than Guernsey,' said petroleum geologist Nigel Smith.
'It's dominated by metamorphic and plutonic rocks of mostly Precambrian age. Your "Jurassic map" goes offshore between the Channel Islands and the southern English coast, but these rocks are too far away to be accessible by drilling from Guernsey.'
The States energy policy adviser, Steve Morris, has also said it happening was uncertain.
He said the process of opening subterranean fissures in rocks to extract oil or gas might be explored one day, but not until the risks were explored fully in other parts of the world.
