For the past two centuries, the majority of global oil supply has come from conventional petroleum reservoirs. These easy-to-harvest reserves are trapped beneath the Earth’s surface by an impermeable layer of rock. Pricking that layer with drill and pipe releases pent-up pressure, generating the (in)famous ‘gusher.’ Soon, however, that pressure ebbs and the oil must be forced to the surface.
Enter the nodding donkey, a sort of mechanical lifting apparatus. The “donkey” forces water into the formation, and then pumps oil-laced water out. The oil is removed for sale, and the water makes another trip down the well to seek out yet more petroleum.
A stubborn fixture of the oil industry since shortly after its foundation, the nodding donkeys face may soon face extinction.
As conventional oil reserves wane and international energy demand surges, unconventional reserves have provoked an elemental shift in what constitutes exploitable petroleum. Unconventional sources, like shale oil and gas, are trapped in impermeable, hard-to-reach rock deep beneath the Earth’s surface. Technological advances, including horizontal drilling and hydraulic fracturing, have made these sources not simply accessible and economically viable, but more accessible and more viable than the nodding donkeys.
Far from being a marginal technology, the new shale sector has already replaced the nodding donkeys as the United States’ top source of petroleum. As of 2014, it has even enabled the United States to become the leading energy producer globally – surpassing Saudi Arabia in oil production and Russia in natural gas production.
For more on how shale is revolutionizing not “just” the American energy industry, but also the global system, see Chapter 7 of The Accidental Superpower as well as my upcoming book, Shale New World.