Research Press Release | June 12, 2015
|Key Points||* Nanodiamonds have been discovered in carbonaceous material in serpentinite.
* Nanodiamonds are formed in the earth’s crust at low temperatures and pressures of less than 300 ºC and 1,000 atmospheric pressure (or atm).
* It is expected that nanodiamonds will also be discovered in sedimentary rock and crude oil.
|Overview||Diamonds found previously have all been formed deep in the earth at high temperatures and pressures. On the other hand, while it was understood that diamonds can be formed experimentally at the low temperatures and pressures associated with the earth’s crust, none had been found in crustal rock.
A joint research team from the Russian Academy of Sciences, Hokkaido University, and the University of Catania has used a variety of methods to analyze carbonaceous material in serpentinite produced by reacting peridotite with water and carbon dioxide at the low temperatures and pressures associated with the earth’s crust. Results show nanodiamonds of a few nm in size.
Furthermore, it is now understood that nanodiamonds are formed in the earth’s crust at temperatures and pressures of less than 300 ºC and 1,000 atmospheric pressure (or atm), and at depths of less than 5 km. This is the first discovery of diamonds produced naturally on the earth at low temperatures and pressures outside the stability region.
Akira KOUCHI, Professor, Astrophysical Chemistry/ Ice & Planetary Science Group, Institute of Low Temperature Science, Hokkaido University
|Publications||Nanodiamond Finding in the Hyblean Shallow Mantle Xenoliths, Scientific Reports (Nature Publishing Group）(2015.6.1)|