Under our feet is a huge treasure: more than a million billion tons of diamonds are below the surface, according to researchers from the Massachusetts Institute of Technology (MIT). But do not expect a diamond rush: The vast treasury lies 145 to 240 kilometers below the surface of the planet, far beyond the distances that are reached today by drilling.
"We can not reach them, but there are many more diamonds than we thought," says Ulrich Faul, researcher at the Department of Planetary, Atmospheric and Earth Sciences at MIT. "It shows that this diamond may not be an exotic mineral, it's relatively common on the scale of things," he added.
Using seismology to analyze how sound waves travel through the earth, researchers have found this treasure in rocks called cratons, which extend across the earth's crust and sink into the mantle. The project began when scientists were surprised by observations that sound waves were significantly accelerated by the roots of ancient craters.
They assembled virtual rocks made up of various combinations of ores to calculate how fast the sound waves would cross them. "Diamond is something special in many ways," says Faul. "One of its characteristics is that its speed of sound is more than twice as fast as in the dominant ore in the upper strata, Olivine."
The scientists then discovered that the only type of rock that met the velocities they had attained proved to contain 1
Made from carbon, diamonds are formed under extreme pressure and extreme temperatures in the deepest part of the earth and rarely appear only by volcanic eruptions near the surface.