Dave N wrote:
[snip]

Nevertheless it is probably indisputable that very significant deposits
of oil shale are to be found beneath Lancashire.

Not just Lancashire. There are probably significant reserves below
Derbyshire. There is evidence in the form of elaterite and the blue
colouring in Blue John of petroleum below the limestone strata. There is
an interesting succession of shale, grit, impermeable basalts and porous
limestone with coal measures at the northern end of the Peak District. The
question there would be permits for extraction in a National Park.