Researchers have discovered evidence of massive diamond deposits at depths of over 150 kilometers. While diamonds are rare near the Earth’s surface and are considered the most expensive gemstones, scientists from MIT in Cambridge and the University of California (Berkeley) have found that they are abundant in the Earth’s interior. Using sound waves, the researchers have determined that diamonds are likely more common than previously thought. The trillion-tonne diamond deposits are located in ancient rock formations called Kratons, which are found in the core areas of pre-Cambrian continents and are typically made up of metamorphic rock. The diamonds are located in the centers of the old tectonic plates and can reach depths of up to 320 kilometers.
The scientists’ measurements suggest that the deepest parts of the Kratons contain up to two percent diamonds. Extrapolating this to the total mass of the Kratons, the researchers estimate that there could be several quadrillion tonnes of diamonds at depths of 150 to 250 kilometers. The researchers discovered the massive diamond deposits due to an anomaly in the speed of sound waves at the end of the Kratons. After conducting extensive experiments in the laboratory and developing complex 3D models, the researchers concluded that the only explanation for the anomaly was the presence of diamonds in the Kraton rock.
While the discovery is exciting, the researchers note that the diamonds are currently unreachable with today’s technology. However, the discovery could lead to new methods for diamond mining in the future. The researchers have published their findings in the journal Geochemistry, Geophysics, Geosystems. Ulrich Faul from MIT explains that “a massive diamond deposit is the only reasonable explanation” for the anomaly in the sound waves. The discovery challenges previous assumptions about the rarity of diamonds and highlights the potential for new discoveries in the Earth’s interior.
