Nonrenewables a Finite and Exhaustible Resource

It is important to distinguish between the commonly used terms, resource, reserve base and reserve  

The extraction of nonrenewable materials follows a common pattern, in that the highest-quality reserves are the first to be extracted, and as these are worked out, progressively lower-quality reserves are then processed. As technology advances and the price of the commodity rises, the reserves increase. 

Calculations of this type are very approximate (obtained by dividing the current reserves by the annual production), but although the figures may be criticized in terms of absolute accuracy, the basic principle that the reserves will eventually be depleted cannot be denied. 

Natural processes are distinguished from the material and energy throughputs of economic processes in two main ways  

Of course, natural systems do not operate outside of the laws of thermodynamics. The process of assimilating atoms to form organized structures requires energy, and this energy is derived (with a few exceptions) from the sun, via photosynthetic processes. 

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