New article on Nature: CaSiO3 perovskite in diamond indicates the recycling of oceanic crust into the lower mantle
F. Nestola, N. Korolev, M. Kopylova, N. Rotiroti, D. G. Pearson, M. G. Pamato, M. Alvaro, Luca Peruzzo*, J. J. Gurney, A. E. Moore & J. Davidson
A CaSiO3 perovskite-structured crystal enclosed in a South African natural diamond has been discovered and studied for the first time. The titanium rich composition of this inclusion indicates a bulk composition consistent with derivation from basaltic oceanic crust subducted to pressures equivalent to those present at the depths of the uppermost lower mantle (780 km). The relatively ‘heavy’ carbon isotopic composition of the surrounding diamond, together with the pristine high-pressure CaSiO3 structure, provides evidence for the recycling of oceanic crust and surficial carbon to lower-mantle depths.
* CNR – Institute of Geosciences and Earth Resources (IGG) – Padua territorial Unit
Nature volume 555, pages 237–241 (08 March 2018)