CaSiO3 perovskite in diamond indicates the recycling of oceanic crust into the lower mantle. / Nestola, F.; Korolev, N.; Kopylova, M.; Rotiroti, N.; Pearson, D. G.; Pamato, M. G.; Alvaro, M.; Peruzzo, L.; Gurney, J. J.; Moore, A. E.; Davidson, J.
In: Nature, Vol. 555, No. 7695, 08.03.2018, p. 237-241.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - CaSiO3 perovskite in diamond indicates the recycling of oceanic crust into the lower mantle
AU - Nestola, F.
AU - Korolev, N.
AU - Kopylova, M.
AU - Rotiroti, N.
AU - Pearson, D. G.
AU - Pamato, M. G.
AU - Alvaro, M.
AU - Peruzzo, L.
AU - Gurney, J. J.
AU - Moore, A. E.
AU - Davidson, J.
PY - 2018/3/8
Y1 - 2018/3/8
N2 - Laboratory experiments and seismology data have created a clear theoretical picture of the most abundant minerals that comprise the deeper parts of the Earth's mantle. Discoveries of some of these minerals in super-deep' diamonds - formed between two hundred and about one thousand kilometres into the lower mantle - have confirmed part of this picture. A notable exception is the high-pressure perovskite-structured polymorph of calcium silicate (CaSiO3). This mineral - expected to be the fourth most abundant in the Earth - has not previously been found in nature. Being the dominant host for calcium and, owing to its accommodating crystal structure, the major sink for heat-producing elements (potassium, uranium and thorium) in the transition zone and lower mantle, it is critical to establish its presence. Here we report the discovery of the perovskite-structured polymorph of CaSiO3 in a diamond from South African Cullinan kimberlite. The mineral is intergrown with about six per cent calcium titanate (CaTiO3). 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. 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.
AB - Laboratory experiments and seismology data have created a clear theoretical picture of the most abundant minerals that comprise the deeper parts of the Earth's mantle. Discoveries of some of these minerals in super-deep' diamonds - formed between two hundred and about one thousand kilometres into the lower mantle - have confirmed part of this picture. A notable exception is the high-pressure perovskite-structured polymorph of calcium silicate (CaSiO3). This mineral - expected to be the fourth most abundant in the Earth - has not previously been found in nature. Being the dominant host for calcium and, owing to its accommodating crystal structure, the major sink for heat-producing elements (potassium, uranium and thorium) in the transition zone and lower mantle, it is critical to establish its presence. Here we report the discovery of the perovskite-structured polymorph of CaSiO3 in a diamond from South African Cullinan kimberlite. The mineral is intergrown with about six per cent calcium titanate (CaTiO3). 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. 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.
KW - DEEP MANTLE
KW - SUPERDEEP DIAMONDS
KW - KANKAN DIAMONDS
KW - PHASE-RELATIONS
KW - PRESSURE
KW - GUINEA
KW - CONSTRAINTS
KW - SYSTEMATICS
KW - INCLUSIONS
KW - CARBON
UR - http://www.scopus.com/inward/record.url?scp=85042643579&partnerID=8YFLogxK
UR - http://www.mendeley.com/research/casio3perovskite-diamond-indicates-recycling-oceanic-crust-lower-mantle
U2 - 10.1038/nature25972
DO - 10.1038/nature25972
M3 - Article
AN - SCOPUS:85042643579
VL - 555
SP - 237
EP - 241
JO - Nature
JF - Nature
SN - 0028-0836
IS - 7695
ER -
ID: 36113899