Remarkably, the tests also uncovered that there was once life present in the water.
Speaking to BBC News, professor Sherwood Lollar said: “When people think about this water they assume it must be some tiny amount of water trapped within the rock.
“But in fact it’s very much bubbling right up out at you. These things are flowing at rates of litres per minute – the volume of the water is much larger than anyone anticipated.”
Discussing the presence of life in the water, Sherwood Lollar added: “By looking at the sulphate in the water, we were able to see a fingerprint that’s indicative of the presence of life. And we were able to indicate that the signal we are seeing in the fluids has to have been produced by microbiology - and most importantly has to have been produced over a very long time scale.
“The microbes that produced this signature couldn’t have done it overnight. This has to be an indication that organisms have been present in these fluids on a geological timescale.”
The professor also revealed that she tried the water for herself – but how did it taste?
“If you’re a geologist who works with rocks, you’ve probably licked a lot of rocks,” Sherwood Lollar told CNN.
She revealed that the water was "very salty and bitter" and "much saltier than seawater."
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