Sunday Times 2
Huge quantities of Earth’s oldest water discovered deep underground
Huge reserves of the oldest water on Earth are locked deep within the planet’s crust and could be home to new forms of life, according to scientists.
Geologists have revealed that they have found water that is up to 2.7 billion years old in sites all over the world.
They now estimate that there could be around 2.5 million cubic miles (11 cubic million km) of this water buried beneath the ground.
This is more than all of the world’s rivers, swamps and lakes put together.
Ancient water rich in hydrogen was found to be bubbling to the surface in a gold mine in South Africa
The scientists have also found tantalising hints that the highly salty water, which is spread out through tiny vein-like networks through the rock, could be home to life.
The water appears to be reacting with the rock to produce large quantities of hydrogen in a similar way to what occurs around deep sea vents.
They claim that this means the water trapped within the Earth’s crust has the potential to support life.
Professor Barbara Sherwood Lollar, a geologist at the University of Toronto, who led the work along with colleagues from Oxford University, said: ‘This represents a quantum change in our understanding of the total volume of the Earth’s crust that may be habitable.’
The researchers took samples of water trapped inside the Precambrian shield rocks – the oldest rocks in the Earth’s crust – from 19 different mines in Canada, South Africa and Scandinavia.
Here they were able to build up estimates for just how much water might be stored down the tiny cracks and pores that have formed in the ancient granite, basalt and quartzite rocks.
Such Precambrian rocks make up around 70 per cent of the Earth’s crust.
In one zinc and copper mine in Timmins, Ontario, the ancient water has been bubbling up to the surface for decades.
Noble gas isotopes, which accumulate in the water over time, have allowed the researchers to estimate the age of this water.
They believe it has been trapped in the rock for more than a billion years and could even be up to 2.7 billion years old, when the rocks first formed.
Speaking to the BBC, Professor Sherwood Lollar said: ‘The rocks are so ancient they contain records of fluid and the atmosphere from the earliest parts of Earth’s history.
‘But simultaneously, they also provide us with information about the chemistry that can support life.’
She said that the huge quantities of hydrogen rich water in the Earth’s crust was a ‘sleeping giant’ that could be a source of possible energy for life.
In 2006 scientists discovered rock and chemical eating bacteria living in Gold mines in South Africa, 1.7 miles (2.8km) under ground.
Here the microbes were found to be using hydrogen and sulfates to survive in the salty water that filled tiny fractures.
Similar types of bacteria have been found living in the hydrothermal vents that form on the sea bed, allowing entire ecosystems to flourish.
Professor Sherwood Lollar and her colleagues believe that there could be entirely new undiscovered forms of life and ancient bacteria living in the viscous salt waters that leak through the oldest rocks in the Earth’s crust.
Their work, which is published in the journal Nature and was also presented at the fall meeting of the American Geophysical Union, could also provide clues about where life on Mars, if it exists, could be found.
Mars surface consists of rocks that are billions of years old and have the potential to produce hydrogen in the same way as those on Earth
Another recent discovery of flourishing colonies of slow growing bacteria in seams of coal, 8000 feet below the sea bed off the coast of Japan.
Professor Sherwood Lollar said: ‘If the ancient rocks of Earth are producing this much hydrogen, it may be that similar processes are taking place on Mars.’
Her colleague, Professor Christ Ballentine, from the University of Oxford, said it was a surprise to find so much water preserved under ground.
He said: ‘When you think about what’s down beneath your feet, it’s more exciting than just some rock.
‘Until our most recent work, the hydrogen production in the continental crust was calculated to be negligible.
‘This was very wrong and our work shows the hydrogen production in the continental crust to be the equal to that produced in the oceanic crust.
‘This doubles the estimate of hydrogen produced on Earth.’
(C) Daily Mail, London