If you've ever stood at the petrol pump wondering what you were putting into your car, you're not alone. Scientist and filmmaker Dr Richard Smith was doing likewise just over a year ago when he had a Eureka moment. "I thought, 'Oil!' Here's this stuff that powers our cars and drives our economy; it plays a huge part in so many areas of our lives and is largely responsible for our environmental problems. But if you ask most people, they don't actually know what it is or where it comes from."
Smith set out to remedy this with a feature-length documentary, a remarkably clear-eyed and ambitious film that spans 160 million years of Earth's history to tell the story of oil.
And what a story it is. Simply put, crude oil is a sludgy soup of ancient algae - microscopic plankton that died, fell to the sea floor and were squashed together, layer upon layer over millions of years. Compacted into carbon-rich beds of shale and clay, they were then cooked underground into what the oil executives like to call "light sweet crude".
"What is really amazing is how the prehistoric remains of these tiny brainless creatures have come back to exert such a sway over the most intelligent life form on the planet," Smith says.
As an energy source, oil has no equal: the power stored in the bonds between its carbon and hydrogen atoms can release 100 times more energy than it takes to get it out of the ground. And it has incredible energy density: as Lord Ron Oxburgh, former chairman of Shell UK, points out, a teacup of petroleum can transport a one-tonne car one kilometre up a mountainside.
Not surprisingly, humans quickly became addicted to oil, and have gobbled up half of all available supplies since the start of commercial exploitation, in 1859, in Pennsylvania. Oil now underpins virtually everything in society, powering transport and the economy, with petrochemical derivatives such as plastic, paints, fertiliser and toothpaste playing indispensable roles in our daily lives. "We're born in a sterile room, caught by someone wearing plastic gloves and are swaddled in a polyester blanket," investigative journalist Sonia Shah says. "We spend our lives bathed in oil."
But as Crude makes clear, there's a price to pay. Carbon dioxide, the gas released when oil is burned, acts as Earth's thermostat. Too little in the atmosphere and the planet will freeze; too much, and it will cook. Levels of carbon dioxide have always fluctuated, most notably during the Jurassic period, 160 million years ago, when today's oil fields started forming.
Back then, the levels grew steadily with volcanic activity over thousands of years, until the planet became super-heated, with anoxic, or stagnant, oceans (hence all that dead plankton) and acid rains. Our consumption of oil is replicating this process, only far more quickly - we are expected to reach carbon levels that are double the pre-industrial levels by the middle of the century, pushing us toward a greenhouse future and climate chaos.
"The worrying thing is that all the evidence points to the fact that the change will come suddenly," Smith says. "The atmosphere becomes saturated with carbon dioxide, and suddenly the climate flips into an uncontrollable cycle of super-heating and oceanic anoxia."
Smith's triumph is in making the science so accessible, telling the tale of oil through computer-generated graphics, expert testimony and a roving camera. From Oman to Oklahoma, Greenland to Saudi Arabia, Smith travels the world to see how crude has shaped us, politically and socially. And always there is the sense of Earth's impossibly long climate cycles, played out over millions of years, in which carbon is the central player, and with which man has been absently tinkering.
"At first I thought, 'how am I going make this interesting?' Then I realised that it wasn't that hard. Oil sweeps throughout human history, with consequences for everyone. When you look at the future and what's going on, everyone has a stake in it."
So is he an optimist? "Put it this way: I don't think it helps to throw your hands in the air in despair. I think there is a popular groundswell of support for change but the politics lags behind. To be forewarned is to be forearmed and hopefully this program will be forewarning people."
oceanic anoxic event