Colorado State University geologist John Ridley is searching the globe for oil – but not the 200- million-year-old oil that energy companies pump out of the ground and into your gas tank.
Ridley is looking for really ancient, billion-year-old oil to serve not as fuel but rather as a key to reveal the story of the creation of life on Earth.
Trapped within these oil droplets – so small they are only a few billionths of a gram – are bits of organic material from life’s earliest days.
“It’s a tiny window into the past,” said Ridley, 49, who came to CSU from Australia two years ago to become the university’s first Edward Warner professor of economic geology.
Ridley and a team that includes researchers at the University of Washington and Australia’s Macquarie University and University of Sydney have gathered ancient rocks, with their tiny oil bubbles, from Canada, Australia and Africa.
A piece of quartz from Elliot Lake, Ontario, has offered up what looks to be a documented peek at life before oxygen blanketed the planet.
One theory of the origins of life is that after the Earth was created about 4.5 billion years ago it took about a billion years for the first one-cell organisms and bacteria to emerge. It was another 2 billion years before bacteria filled the atmosphere with oxygen.
“What we are trying to do is create a timeline to see when life changed,” Ridley said.
After carefully washing the Ontario quartz to remove traces of recent life that could contaminate the sample – a 30-step process – a little bubble of oil, hardly a billionth of an ounce, was extracted.
What the researchers gleaned from this drop was that complex cells and oxygen-generating cynobacteria existed about 2.45 billion years ago. That is about 700 million years earlier than previously thought and 150 million years before an oxygen atmosphere.
The findings help buttress the theory that the bacteria were responsible for changing the atmosphere’s oxygen levels, the researchers say.
The Ridley team findings were published in the journal Geology this summer.
The goal of the timeline is to better understand the interplay between evolution and the environment, Ridley said.
“Life was actually pretty static for a billion years,” he said. “There wasn’t much evolution. When we see change in life, we have to go back and see what was happening on the Earth.”
And is this economic geology?
“My specialty is fluids,” Ridley said, noting that a lot of geology focuses on fluids like petroleum and water deep in the Earth’s crust, which is key in producing gold ore.
The ancient-oil research, Ridley said, “is valuable in another way.”
Staff writer Mark Jaffe can be reached at 303-954-1912 or mjaffe@denverpost.com.
