The origin of Earth’s water is a naturalistic enigma. Many scientists used to believe that comets brought it here.
However, new research published in the journal Earth and Planetary Science Letters suggests that chemical reactions in Earth’s mantle may have produced much of our planet’s water.
This conclusion is based on a computer simulation “of reactions in Earth’s upper mantle between liquid hydrogen and quartz, the most common and stable form of silica in this part of the planet,” as New Scientist put it.
The article goes on to explain:
“’This is one way water can form on Earth,’ says team member John Tse at the University of Saskatchewan in Canada. ‘We show it’s possible to have water forming in Earth’s natural environment, rather than being of extraterrestrial origin.’
The simple reaction takes place at about 1400 °C and pressures 20,000 times higher than atmospheric pressure as silica, or silicon dioxide, reacts with liquid hydrogen to form liquid water and silicon hydride.”