Scientists locate massive underground water reservoir, ‘three times’ the size of Earth’s oceans

June 14, 2014

Researchers have found a massive reservoir of water three times the size of Earth’s oceans located hundreds of miles beneath the surface of the planet. Scientists from Northwestern University and the University of New Mexico provided the first ever evidence for potentially oceans worth of water deep beneath the United States.
Though the water is not in the general liquid form — the elements for water are bound up in rock deep in the planet’s mantle — the discovery may correspond to earth’s biggest water reservoir. It is due to the presence of liquid water on the surface that makes our planet fit for human habitation, and researchers have long been trying to puzzle out just how much water may be cycling between Earth’s surface and internal reservoirs through plate tectonics.
Researchers have discovered deep pockets of magma situated about 400 miles underneath North America, a possible sign of the presence of water at these depths. The discovery indicates that water from the Earth’s surface can reach such great depths by plate tectonics, in due course causing partial melting of the rocks found deep in the mantle. Scientists are considering evidence for a whole-Earth water cycle, which may help explain the huge quantity of liquid water on the surface earth. Researchers have been in quest of this missing deep water for years. They have long conjectured that water is locked in a rocky layer of the Earth’s mantle between the lower mantle and upper mantle, at depths between 250 miles and 410 miles.
Scientists Jacobsen and Schmandt are the first to provide direct proof that there may be water in “Transition Zone” of the mantle on a regional scale. Scientists tried to produce evidence that melting may take place about 400 miles deep in the Earth. H₂O trapped in mantle rocks, such as those comprising the mineral ringwoodite is the fundamental thing to the process. If just 1% of the weight of mantle rock in this zone is H₂O that would be tantamount to around 3 times the amount of water in oceans on Earth’s surface.
The water which has been discovered is not in the form of liquid, ice or vapor. It is water locked inside the molecular composition of the minerals in the mantle rock. The high pressure and temperature produced by the weight of 250 miles of solid rock breaks a water molecule to form a hydroxyl radical (OH), which can bind into a mineral’s crystal structure.
The research rests on a discovery in which researchers found a piece of the mineral ringwoodite inside a diamond spewed from a depth of 400 miles by a volcano in Brazil. That minuscule piece of ringwoodite — the only sample in existence from within the Earth — contained an unexpected quantity of water bound in solid form in the mineral.