For land producing minerals, there is a special tax rule called “percentage depletion” available to some taxpayers. With percentage depletion, the owner can deduct a fixed percentage (15%) of gross income every year. This can add up to more than the original amount invested in an oil field.

Normally, the depreciation allowance for capital investment over a period of years can only add up to the amount originally invested.

Spending money on a commodity isn't like buying a mainframe. And these are specific deductions and claims for fossil fuel products.