The world's oil supply in the long term, consists of conventional oil reserves (light or heavy crude oil) and non-conventional reserves (oil sands, shale which are mined rather than drilled). Reserves are defined as proven deposits of oil which are economically feasible at current or expected prices.
So-called "peaker" deliberation about the so-called end of oil, or the exhausting of conventional oil reserves is discussed at peak oil. More credibly:
Global oil supply will not itself be curtailed by any such events, as the reservers are not the supply: fuel oil and gasoline equivalents can be made from a coal to oil or biodiesel or oil sand or oil shale refining process, none of which are running out in the near term.
The reality is that peak oil, gas supply, energy, energy industry, energy supply, energy demand issues are all short term, simply a question of adaption and price shocks, and that the questions of combustion and sustainable infrastructure are far more important longer term.
Accordingly the issues related to oil supply in the large are somewhat similar to those related to climate and biodiversity:
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