Groundwater that was recently discovered deep underground in a mine in South Africa is estimated to be 1.2 billion years old. Researchers suspect that the groundwater is some of the oldest on the planet, and its chemical interactions with the surrounding rock could offer new insights about energy production and storage in Earth’s crust.
In fact, Oliver Warr, a research associate in the department of Earth sciences at the University of Toronto in Canada and lead author of a new study about the groundwater discovery, described the location in a statement as a “Pandora’s box of helium-and-hydrogen-producing power.”
The South African groundwater was also enriched in the highest concentration of radiogenic products — elements produced by radioactivity — yet discovered in fluids, according to the study, demonstrating that ancient groundwater sites may one day potentially serve as energy sources.
The gold and uranium mine, known as Moab Khotsong, sits about 100 miles (161 kilometers) southwest of Johannesburg and is home to one of the world’s deepest mine shafts, plunging to depths of 1.86 miles (3 km) below the surface at its deepest, according to the mine (opens in new tab).
The new find follows the prior discovery of approximately 1.8 billion-year-old groundwater made during a 2013 research expedition (also led by Warr). That finding occurred at Kidd Creek Mine in Ontario, which lies beneath the Canadian Shield, a geologic structure comprised of igneous