From Max Schulz’s Running Out of Oil? History, Technology and Abundance:
Almost since the first discoveries of oil in the U.S. in 1859, people have been saying we’re running out. In 1874, the state geologist of the nation’s leading oil producer, Pennsylvania, warned the U.S. had enough oil to last just four years. In 1914, the federal government said we had a ten-year supply. The government announced in 1940 that reserves would be depleted within a decade and a half. The Club of Rome made similar claims in the 1970s. President Carter famously predicted in 1977 that unless we made drastic cuts in our oil consumption, ‘Within ten years we would not be able to import enough oil — from any country, at any acceptable price.’ And so it goes today, where a slew of books and Web sites make fantastic claims about dwindling supplies of crude.The chief problem with those who say the world is running out is that they have always looked at the issue the wrong way. Questions about energy supply shouldn’t be thought of in terms of how much is available, but in terms of how good mankind is at finding and extracting it.
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In 1970, experts believed the world had 612 billion barrels of proved reserves. Over the next three decades, more than 767 billion barrels would be pumped. Did we use up all the world’s oil and then some? Hardly. Conservative estimates today place the world’s provable oil reserves at 1.2 trillion barrels. New deposits of oil haven’t been created. It’s just that human ingenuity has come up with ways to get hard-to-reach deposits.