January/February 2004, Volume 60, No. 1, pp. 20-22, 70
Oil: The illusion of plenty
By Alfred Cavallo
One hundred and twelve billion of anything sounds like a limitless quantity. But in terms of barrels of oil, it's just a drop in the gas tank. The world uses about 27 billion barrels of oil per year, meaning that 112 billion barrels--the proven oil reserves of Iraq, the second largest proven oil reserves in the world--would last a little more than four years at today's usage rates.
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