Groundwater
A well in the Western Desert of Egypt. The team from the ANL used radio-krypton dating to determine that the water has been underground for half a million years (image credit: ANL)
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A website from the Institute of Physics
A website from the Institute of Physics
A well in the Western Desert of Egypt. The team from the ANL used radio-krypton dating to determine that the water has been underground for half a million years (image credit: ANL)