A note on 'running out'
        The main reason why the 'running out of minerals (including oil)' scenarios in The Limits to Growth (1972) have not materialised is that they were based on a confusion about categories of resources  -  admirably cleared up in Ehrlich, Ehrlich & Holdren 'Ecoscience' (Freeman 1977).  The Meadowses (and the Ehrlichs in their 1st edn, 1972) had not grasped that mining companies do not bother to prove  -  by drilling 2 or more holes thru lodes  -  resources corresponding to more than a couple decades of projected sales.  Thus, Proven Reserves are in general much smaller than Probable Reserves.  The latter can be pretty confident just from seismic mapping but cannot qualify as Proven. 
        Failure to accelerate consumption of oil as fast as projected in 1972 is not hugely due to increased efficiency of use; much of the conserved oil is due to switching to other energy sources, failure of GNPs to accelerate as projected, and of course some deterrence of consumption by the OPEC price-hikes just after these pioneering 1972 books.
Finally, I wish people would face up to the astronomical lodes of primeval (not fossil) gas pointed out by the formidable Prof Gold in his book The Hot Deep Biosphere  - and perhaps Cornell has kept available his <http://www.people.cornell.edu/pages/tg21/ > .   Given 8-10km holes, many centuries' worth of natural gas can almost certainly be brought up almost anywhere.    Lubricants, no; but fuel  -  you better believe it.
R