TECH

Huge diamond reserve is detected below the Earth's surface
There is a huge treasure trove of diamonds buried beneath the earth. More than a quadrillion tons of diamonds - a thousand times more than a trillion - have announced US researchers at the Massachusetts Institute of Technology (MIT) this week.But do not expect a race for diamonds. These precious minerals are located much more deeply than any drilling expedition has ever reached, some 145 to 240 kilometers below the surface of the planet."We can not pick them up, but there are still a lot more diamonds than we've ever imagined before," said Ulrich Faul, a researcher at MIT's Department of Earth, Atmospheric and Planetary Sciences."This shows that the diamond may not be this exotic mineral, but, on the scale of things, relatively common."Using seismic technology to analyze how sound waves pass through Earth, scientists have detected the treasure in rocks called cratonic roots, which are in the form of inverted mountains that extend from the earth's crust to the mantle.
These are "the oldest and most immobile parts of the rocks, which lie below the center of most continental tectonic plates," MIT said in a statement.The project to discover the Earth's deep diamonds began because scientists were intrigued by the observations that sound waves accelerated significantly as they passed through the roots of ancient kratons.So they set up virtual stones, made from various combinations of minerals, to calculate how quickly the sound waves would travel through them."The diamond is special in many ways," said Faul. "One of its special properties is that the speed of sound in the diamond is twice as fast as in the dominant mineral in the rocks of the upper mantle, the olivine."They found that the only type of rock that equated to the speed detected in the craton contained 1% to 2% diamond.Scientists now believe that the Earth's ancient underground rocks contain at least a thousand times more diamonds than previously expected.
Still, very few of these gems should reach the jewelry stores.



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