TORONTO -- Life found in ancient water flowing through a northern Ontario mine could eventually help scientists unlock the mystery about whether there was ever life on Mars, according to a scientist at the University of Toronto.
Barbara Sherwood Lollar, a professor of geochemistry, led a team of researchers at the Kidd Creek mine north of Timmins, Ont. that extracted the oldest sample of water ever found – almost 2 billion years old – from 2.4 kilometres underground.
Sherwood Lollar studied water in other mines in northern Europe and southern Africa, finding samples dating back tens of millions to hundreds of millions of years. She then invited a team of scientists to Kidd Creek Mine, a copper and zinc mine that is the “gold standard” for well-preserved ancient rock.
The mine is within the rocks of the Canadian Shield, the exposed part of the continental crust that makes up about half of Canada’s land mass. The Canadian Shield has some of the oldest rocks on Earth, ranging from 2.7 billion to three billion years old.
“These are some of the best-preserved ancient rocks on the planet,” Sherwood Lollar told CTV’s Your Morning on Monday.
Sherwood Lollar says the team was surprised just how old the Kidd Creek water turned out to be and that they’ve been able to isolate microbes living within some of the samples. This is evidence of life deep in the crust of the Earth, entirely hidden from the energy of the sun.
This life – rock-eating microbes – relies instead on the chemistry created by the reaction of water and rock. The reaction over long periods of time creates highly salinized water, about five to 10 times the saltiness of sea water.
Studying the Canadian Shield is a great test run for eventually doing the same work on Mars, said Sherwood Lollar, because the ancient rock is about as close as scientists can get to the red planet’s conditions.
“It’s actually a really fun fact for Canadians to understand, that the Canadian Shield is, in fact, one of the best analogs for Mars.”
If there is any evidence of past life on Mars, dating back three or four billion years, it won’t be found in the desert of the planet’s surface, said Sherwood Lollar. It will be in the subsurface, and quite likely in deep subsurface water.
“Around the time life arose on Earth, Mars was a much happier place. Right now, it’s a cold, dry desert but at that time it may have been warmer and wetter. And it’s at least theoretically possible that around the time that life arose on our planet, it may also have arisen on Mars.”
Sherwood Lollar’s work, over more than 30 years, earned her the Gerhard Herzberg gold medal in 2019, which is Canada’s top honour for non-medical research. The award from the Natural Sciences and Engineering Research Council came with a $1 million in research funding over five years.
A sample of the billion-year-old water is on display at Ottawa’s Ingenium – Canada’s Museums of Science and Innovation. It’s the oldest artifact acquired by Ingenium.
