Allowances are given under CAA01/S394 (1) to a person "who
carries on a trade of mineral extraction in respect of qualifying
expenditure incurred by him for the purposes of that trade".
"Trade of mineral extraction" is defined in CAA01/S394 (2) as
a trade that consists of or includes the working of a source of
mineral deposits.
CAA01/S394 (3) defines "mineral deposits" to include:
It therefore includes mines, oil wells and geothermal energy sources (CAA01/S394 (5)).