Huge ocean of water locked in earth's crust
VAST amounts of water - up to three times as much as in all the oceans - are now thought to be trapped under the Earth's crust.
Seventy per cent of the earth's surface is made up of water, but this is only a drop in the ocean, compared with what can be found about 660km underground, said a study in the journal Science.
But it is not sloshing around under our feet. Locked into the molecular structure of minerals that absorb water, it is not liquid, or even ice.
Northwestern University geophysicist Steve Jacobsen, who co-authored the study, said that the finding suggests that our water came from within and helps explains how oceans formed.
"I think we are finally seeing evidence for a whole-earth water cycle, which may help explain the vast amount of liquid water on our planet," he told The Guardian.