Trove Of Water 400Km Beneath Earth's Surface

Seventy percent of the Earth’s surface is water. But that’s what just meets the eye. A trove of water – in fact as much water as all the oceans on the planet’s surface combined – is hiding 400km beneath our feet. Geoscientists had earlier thought that below the transition zone where the Earth’s mantle meets the crust (at 410km), a water filled mineral called brucite was unstable and decomposed. As they decomposed; they released the water, which was recycled back to surface via volcanic activity. But this discovery of a new high-pressure phase of brucite indicates that water could be efficiently transported to far deeper realms without decomposition, reports LiveScience.com. But new research suggests that before brucite which is 50% magnesium oxide and 50% water – decomposes, it transforms into another, more stable 3D structure. The finding, which was detailed in the journal Proceedings of the National Academy of Sciences, means there’s a stash of water located deeper in the Earth than was previously thought. Unable to probe the deep Earth directly, researchers used quantum mechanical calculations, analyzing various possible structures for brucite in deep Earth conditions. After months of running various structure through their computer programme, the researchers found a previously unknown phase of brucite that would be able to withstand the high pressures found in the lower mantle. Current estimates suggest that the deep Earth may hold as much water as all the oceans on the planet. This water and the additional trove brucite may also hold, are vitally important to the movement of materials through the Earth. As water containing minerals travel down through the Earth’s layers, the materials decompose, releasing the water that makes its way back to the surface, often through volcanic activity.