Billion-Year-Old Water Preserved in Canadian Mine
The ancient water contains chemicals that could support life without sunlight.
Ker Than
for National Geographic
Published May 18, 2013
Pockets of water trapped in rocks from a Canadian mine are over a billion years old, and the water could contain life forms that can survive independently from the sun, scientists said this week.
The ancient water was collected from boreholes at Timmins Mine beneath Ontario, Canada, at a depth of about 1.5 miles (2.4 kilometers).
"When these rocks formed, this part of Canada was the ocean floor," said study co-author Barbara Sherwood Lollar, an Earth scientist at Canada's University of Toronto.
"When we go down [into the mine] with students, we like to say imagine you're walking on the seafloor 2.6 billion years ago."
Working with U.K. colleagues Chris Ballentine and Greg Holland, Sherwood Lollar and her team found that the water was rich in dissolved gases such as hydrogen and methane, which could provide energy for microbes like those found around hydrothermal vents in the deep ocean.
In addition, the water contained different rare gases that include the elements helium, neon, argon, and xenon, which were created through interactions with the surrounding radioactive rock. By measuring the concentrations of isotopes of these "noble gases"—so called because they rarely interact with other elements—the team could estimate how long the water had been trapped underground and whether it had been isolated.
Depending on the noble gas analyzed, the age estimates for the water varied between 1.1 billion years old and 2.6 billion years old—or as old as the rocks in the mine itself.
"It shows us that there's been very little mixing between this water and the surface water," Sherwood Lollar said. "What we want to do with further work is see if we can narrow that [age range] down."
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The ancient water contains chemicals that could support life without sunlight.
Ker Than
for National Geographic
Published May 18, 2013
Pockets of water trapped in rocks from a Canadian mine are over a billion years old, and the water could contain life forms that can survive independently from the sun, scientists said this week.
The ancient water was collected from boreholes at Timmins Mine beneath Ontario, Canada, at a depth of about 1.5 miles (2.4 kilometers).
"When these rocks formed, this part of Canada was the ocean floor," said study co-author Barbara Sherwood Lollar, an Earth scientist at Canada's University of Toronto.
"When we go down [into the mine] with students, we like to say imagine you're walking on the seafloor 2.6 billion years ago."
Working with U.K. colleagues Chris Ballentine and Greg Holland, Sherwood Lollar and her team found that the water was rich in dissolved gases such as hydrogen and methane, which could provide energy for microbes like those found around hydrothermal vents in the deep ocean.
In addition, the water contained different rare gases that include the elements helium, neon, argon, and xenon, which were created through interactions with the surrounding radioactive rock. By measuring the concentrations of isotopes of these "noble gases"—so called because they rarely interact with other elements—the team could estimate how long the water had been trapped underground and whether it had been isolated.
Depending on the noble gas analyzed, the age estimates for the water varied between 1.1 billion years old and 2.6 billion years old—or as old as the rocks in the mine itself.
"It shows us that there's been very little mixing between this water and the surface water," Sherwood Lollar said. "What we want to do with further work is see if we can narrow that [age range] down."
Read More :
http://
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