A pocket of ancient water discovered in the depths of a Canadian goldmine may provide vital clues about the way life evolved on Earth. Scientists from universities in Britain and Canada say that the water is at least 1.5 billion years old – and may in fact be a lot older – and that any microbes detected within it would have evolved on a completely separate path to anything known on the surface.
The water was found seeping from boreholes drilled by miners almost 1.5 miles below Timmins, Ontario, and is far and away the oldest body of water yet discovered. Minute quantities of water which may be even older are sometimes found trapped in mineral rock, but the only other genuine pocket of ancient water known to scientists was found in South Africa’s Witwatersrand Basin several years ago. That water was ‘only’ tens of millions of years old, but it did contain evidence of primordial life.
According to Professor Chris Ballentine from Manchester University, the South African waters have an “almost identical chemistry” to that of the Canadian find, and importantly, “they contain microbes that have adapted to that environment.” Scientists are optimistic that a similar discovery may be made following close analysis of the water from Timmins as it is a potentially viable ecosystem. Although it has long been hidden far from any light, its chemical makeup includes dissolved hydrogen and methane gases which could sustain certain types of micro-organism.
The water has been tested using a complex laboratory procedure which involves studying isotopes of common elements – such as hydrogen and helium – which decay at known intervals. Isotopes of the noble gas, xenon, are also used to gain a rough estimate of when the water was last in contact with the surface atmosphere. This process only gives a broad idea of the water’s age, however, and scientists think it could be anywhere from 1.5 to 2.5 billion years old. These are staggering figures, which pre-date the dinosaurs by 750 million years and offer a glimpse at a time when the Earth was half its present age.
If evidence of life – no matter how simple – is detected, it will open up all sorts of possibilities for something similar to be found on other worlds. Mars, for example, may have been a warmer and wetter place in its distant past, and scientists have not discounted the chances that micro-organic life might have developed there billions of years ago. According to Carol Stoker, a research scientist with NASA, “If you go back to the very early history of Earth and Mars, to the first billion years after the surfaces cooled, Earth and Mars looked very similar.” Mars still has water present at its polar ice caps, and there is the likelihood that pockets of water are also trapped deep beneath its surface.
The ramifications of life being detected in the Canadian water are, therefore, profound. As Carol Stoker says, “The logic is if that happened on Earth, why shouldn’t it have happened on Mars?”
