Highly saline fluids from a subducting slab as the source for fluid-rich diamonds

Yaakov Weiss; John McNeill; D. Graham Pearson; Geoff M. Nowell; Chris J. Ottley

doi:10.1038/nature14857

Highly saline fluids from a subducting slab as the source for fluid-rich diamonds

Yaakov Weiss^*, John McNeill, D. Graham Pearson, Geoff M. Nowell, Chris J. Ottley

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

130 Scopus citations

Abstract

The infiltration of fluids into continental lithospheric mantle is a key mechanism for controlling abrupt changes in the chemical and physical properties of the lithospheric root, as well as diamond formation, yet the origin and composition of the fluids involved are still poorly constrained. Such fluids are trapped within diamonds when they form and so diamonds provide a unique means of directly characterizing the fluids that percolate through the deep continental lithospheric mantle. Here we show a clear chemical evolutionary trend, identifying saline fluids as parental to silicic and carbonatitic deep mantle melts, in diamonds from the Northwest Territories, Canada. Fluid-rock interaction along with in situ melting cause compositional transitions, as the saline fluids traverse mixed peridotite-eclogite lithosphere. Moreover, the chemistry of the parental saline fluids - especially their strontium isotopic compositions - and the timing of host diamond formation suggest that a subducting Mesozoic plate under western North America is the source of the fluids. Our results imply a strong association between subduction, mantle metasomatism and fluid-rich diamond formation, emphasizing the importance of subduction-derived fluids in affecting the composition of the deep lithospheric mantle.

Original language	American English
Pages (from-to)	339-342
Number of pages	4
Journal	Nature
Volume	524
Issue number	7565
DOIs	https://doi.org/10.1038/nature14857
State	Published - 19 Aug 2015
Externally published	Yes

Bibliographical note

Funding Information:
Acknowledgements Y.W. acknowledges his Lamont postdoctoral fellowship and National Science Foundation grant no. 1348045. We thank T. Stachel and D. Walker for discussions and J. J. Gurney, J. Carlson, T. Nowicki and BHP Minerals/Dominion Diamonds for access to diamonds from the Ekati mine. J.M. was funded by a scholarship from the Diamond Trading Company at Durham University. D.G.P. completed this work under tenure of a Canada Excellence Research Chair, with support from the Deep Carbon Observatory (Sloan Foundation). Y.W. thanks Israel Science Foundation grant number 435/12 for funding the EPMA and Fourier transform infrared (FTIR) analyses at the Hebrew University. D. E. Jacob, M. Santosh and M. Walter made excellent suggestions that greatly improved this paper. This is Lamont–Doherty Earth Observatory contribution number 7908.

Publisher Copyright:
© 2015 Macmillan Publishers Limited. All rights reserved.

Access to Document

10.1038/nature14857

Cite this

@article{5f205b24316649e792cb3dcc4187f01a,

title = "Highly saline fluids from a subducting slab as the source for fluid-rich diamonds",

abstract = "The infiltration of fluids into continental lithospheric mantle is a key mechanism for controlling abrupt changes in the chemical and physical properties of the lithospheric root, as well as diamond formation, yet the origin and composition of the fluids involved are still poorly constrained. Such fluids are trapped within diamonds when they form and so diamonds provide a unique means of directly characterizing the fluids that percolate through the deep continental lithospheric mantle. Here we show a clear chemical evolutionary trend, identifying saline fluids as parental to silicic and carbonatitic deep mantle melts, in diamonds from the Northwest Territories, Canada. Fluid-rock interaction along with in situ melting cause compositional transitions, as the saline fluids traverse mixed peridotite-eclogite lithosphere. Moreover, the chemistry of the parental saline fluids - especially their strontium isotopic compositions - and the timing of host diamond formation suggest that a subducting Mesozoic plate under western North America is the source of the fluids. Our results imply a strong association between subduction, mantle metasomatism and fluid-rich diamond formation, emphasizing the importance of subduction-derived fluids in affecting the composition of the deep lithospheric mantle.",

author = "Yaakov Weiss and John McNeill and Pearson, {D. Graham} and Nowell, {Geoff M.} and Ottley, {Chris J.}",

note = "Funding Information: Acknowledgements Y.W. acknowledges his Lamont postdoctoral fellowship and National Science Foundation grant no. 1348045. We thank T. Stachel and D. Walker for discussions and J. J. Gurney, J. Carlson, T. Nowicki and BHP Minerals/Dominion Diamonds for access to diamonds from the Ekati mine. J.M. was funded by a scholarship from the Diamond Trading Company at Durham University. D.G.P. completed this work under tenure of a Canada Excellence Research Chair, with support from the Deep Carbon Observatory (Sloan Foundation). Y.W. thanks Israel Science Foundation grant number 435/12 for funding the EPMA and Fourier transform infrared (FTIR) analyses at the Hebrew University. D. E. Jacob, M. Santosh and M. Walter made excellent suggestions that greatly improved this paper. This is Lamont–Doherty Earth Observatory contribution number 7908. Publisher Copyright: {\textcopyright} 2015 Macmillan Publishers Limited. All rights reserved.",

year = "2015",

month = aug,

day = "19",

doi = "10.1038/nature14857",

language = "American English",

volume = "524",

pages = "339--342",

journal = "Nature",

issn = "0028-0836",

publisher = "Nature Publishing Group",

number = "7565",

}

TY - JOUR

T1 - Highly saline fluids from a subducting slab as the source for fluid-rich diamonds

AU - Weiss, Yaakov

AU - McNeill, John

AU - Pearson, D. Graham

AU - Nowell, Geoff M.

AU - Ottley, Chris J.

N1 - Funding Information: Acknowledgements Y.W. acknowledges his Lamont postdoctoral fellowship and National Science Foundation grant no. 1348045. We thank T. Stachel and D. Walker for discussions and J. J. Gurney, J. Carlson, T. Nowicki and BHP Minerals/Dominion Diamonds for access to diamonds from the Ekati mine. J.M. was funded by a scholarship from the Diamond Trading Company at Durham University. D.G.P. completed this work under tenure of a Canada Excellence Research Chair, with support from the Deep Carbon Observatory (Sloan Foundation). Y.W. thanks Israel Science Foundation grant number 435/12 for funding the EPMA and Fourier transform infrared (FTIR) analyses at the Hebrew University. D. E. Jacob, M. Santosh and M. Walter made excellent suggestions that greatly improved this paper. This is Lamont–Doherty Earth Observatory contribution number 7908. Publisher Copyright: © 2015 Macmillan Publishers Limited. All rights reserved.

PY - 2015/8/19

Y1 - 2015/8/19

N2 - The infiltration of fluids into continental lithospheric mantle is a key mechanism for controlling abrupt changes in the chemical and physical properties of the lithospheric root, as well as diamond formation, yet the origin and composition of the fluids involved are still poorly constrained. Such fluids are trapped within diamonds when they form and so diamonds provide a unique means of directly characterizing the fluids that percolate through the deep continental lithospheric mantle. Here we show a clear chemical evolutionary trend, identifying saline fluids as parental to silicic and carbonatitic deep mantle melts, in diamonds from the Northwest Territories, Canada. Fluid-rock interaction along with in situ melting cause compositional transitions, as the saline fluids traverse mixed peridotite-eclogite lithosphere. Moreover, the chemistry of the parental saline fluids - especially their strontium isotopic compositions - and the timing of host diamond formation suggest that a subducting Mesozoic plate under western North America is the source of the fluids. Our results imply a strong association between subduction, mantle metasomatism and fluid-rich diamond formation, emphasizing the importance of subduction-derived fluids in affecting the composition of the deep lithospheric mantle.

AB - The infiltration of fluids into continental lithospheric mantle is a key mechanism for controlling abrupt changes in the chemical and physical properties of the lithospheric root, as well as diamond formation, yet the origin and composition of the fluids involved are still poorly constrained. Such fluids are trapped within diamonds when they form and so diamonds provide a unique means of directly characterizing the fluids that percolate through the deep continental lithospheric mantle. Here we show a clear chemical evolutionary trend, identifying saline fluids as parental to silicic and carbonatitic deep mantle melts, in diamonds from the Northwest Territories, Canada. Fluid-rock interaction along with in situ melting cause compositional transitions, as the saline fluids traverse mixed peridotite-eclogite lithosphere. Moreover, the chemistry of the parental saline fluids - especially their strontium isotopic compositions - and the timing of host diamond formation suggest that a subducting Mesozoic plate under western North America is the source of the fluids. Our results imply a strong association between subduction, mantle metasomatism and fluid-rich diamond formation, emphasizing the importance of subduction-derived fluids in affecting the composition of the deep lithospheric mantle.

UR - http://www.scopus.com/inward/record.url?scp=84939824545&partnerID=8YFLogxK

U2 - 10.1038/nature14857

DO - 10.1038/nature14857

M3 - Article

AN - SCOPUS:84939824545

SN - 0028-0836

VL - 524

SP - 339

EP - 342

JO - Nature

JF - Nature

IS - 7565

ER -

Highly saline fluids from a subducting slab as the source for fluid-rich diamonds

Abstract

Bibliographical note

Access to Document

Other files and links

Fingerprint

Cite this