The ‘Hubbert’s Peak’ approach to oil reserves has fostered the notion that resource-limitation has already begun. Contrary to the assumptions of sustainability, this analysis of existing production of 16 resources finds no evidence of such limitation.
Dr James Rustad promptly sent me an excel spreadsheet with the calculations for gold, a mineral not shown in his paper. It is easy to work out the procedure from the spreadsheet. The cumulative productions are divided by the initial production, and the final cumulative production, to make the X and Y axes.
Here are more resources (h/t JRustad).
I particularly like the paper (it’s short), and the procedure (using a transformed model), and the purpose of examining basic assumptions. As he says:
Underpinning the recent focus on sustainability is the assumption that, for many raw materials, resource depletion is imminent.
Several resources often popularly perceived as exhibiting “peak” or logistic behavior, such as the rare earth elements, lithium, and helium show no evidence for a finite Qtot at any point in their production histories.
But of course…
The fact that production of a given resource is growing exponentially does not imply that the resource is inexhaustible.