Grain boundaries as reservoirs of incompatible elements in the Earth's mantle

Abstract

The concentrations and locations of elements that strongly partition into the fluid phase in rocks provide essential constraints on geochemical and geodynamical processes in Earth's interior. A fundamental question remains, however, as to where these incompatible elements reside before formation of the fluid phase. Here we show that partitioning of calcium between the grain interiors and grain boundaries of olivine in natural and synthetic olivine-rich aggregates follows a thermodynamic model for equilibrium grain-boundary segregation. The model predicts that grain boundaries can be the primary storage sites for elements with large ionic radius—that is, incompatible elements in the Earth's mantle. This observation provides a mechanism for the selective extraction of these elements and gives a framework for interpreting geochemical signatures in mantle rocks.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Chemistry and structure of olivine-olivine grain boundaries in a sample of olivine + anorthite annealed at 1,473 K.
Figure 2: Calcium concentrations in olivine grain boundaries versus concentration in olivine grain matrices.
Figure 3: Ratio of solute concentration in a system composed of grain matrices + grain boundaries, CGM+GB, to that of a system composed of grain matrices alone, CGM, versus ionic radius at a temperature of 1,473 K.

References

  1. 1

    Hiraga, T., Anderson, I. M. & Kohlstedt, D. L. Chemistry of grain boundaries in mantle rocks. Am. Mineral. 88, 1015–1019 (2003)

    ADS  CAS  Article  Google Scholar 

  2. 2

    McLean, D. Grain Boundaries in Metals 346 (Clarendon, Oxford, 1957)

    Google Scholar 

  3. 3

    Menzies, M. M. & Murthy, V. R. Strontium isotope geochemistry of alpine tectonite lherzolites: Data compatible with a mantle origin. Earth Planet. Sci. Lett. 38, 346–354 (1978)

    ADS  CAS  Article  Google Scholar 

  4. 4

    Ottonello, G. Rare earth abundances and distribution in some spinel peridotite xenoliths from Assab (Ethiopia). Geochim. Cosmochim. Acta 44, 1885–1901 (1980)

    ADS  CAS  Article  Google Scholar 

  5. 5

    Fraser, D. G., Watt, F., Grime, G. W. & Takacs, J. Direct determination of strontium enrichment on grain boundaries in a garnet lherzolite xenolith by proton microprobe analysis. Nature 312, 352–354 (1984)

    ADS  CAS  Article  Google Scholar 

  6. 6

    Stosch, H.-G., Lugmair, G. W. & Kovalenko, V. I. Spinel peridotite xenoliths from the Tariat Depression, Mongolia. II: Geochemistry and Nd and Sr isotopic composition and their implications for the evolution of the subcontinental lithosphere. Geochim. Cosmochim. Acta 50, 2601–2614 (1986)

    ADS  CAS  Article  Google Scholar 

  7. 7

    Suzuki, K. Grain-boundary enrichment of incompatible elements in some mantle peridotites. Chem. Geol. 63, 319–334 (1987)

    ADS  CAS  Article  Google Scholar 

  8. 8

    Zindler, A. & Jagoutz, E. Mantle cryptology. Geochim. Cosmochim. Acta 52, 319–333 (1988)

    ADS  CAS  Article  Google Scholar 

  9. 9

    Ionov, D. A., Kramm, U. & Stosch, H.-G. Evolution of the upper mantle beneath the southern Baikal rift zone: an Sr-Nd isotope study of xenoliths from the Bartoy volcanoes. Contrib. Mineral. Petrol. 111, 235–247 (1992)

    ADS  CAS  Article  Google Scholar 

  10. 10

    Xu, X., O'Reilly, S. Y., Griffin, W. L. & Zhou, X. Enrichment of upper mantle peridotite: petrological, trace element and isotopic evidence in xenoliths from SE China. Chem. Geol. 198, 163–188 (2003)

    ADS  CAS  Article  Google Scholar 

  11. 11

    Hiraga, T., Anderson, I. M., Zimmerman, M. E., Mei, S. & Kohlstedt, D. L. Structure and chemistry of grain boundaries in deformed, olivine + basalt and partially molten lherzolite aggregates: Evidence of melt-free grain boundaries. Contrib. Mineral. Petrol. 144, 163–175 (2002)

    ADS  CAS  Article  Google Scholar 

  12. 12

    Waff, H. S. & Holdren, G. R. The nature of grain boundaries in dunite and lherzolite xenoliths: Implications for magma transport in refractory upper mantle material. J. Geophys. Res. 86, 3677–3683 (1981)

    ADS  CAS  Article  Google Scholar 

  13. 13

    Tan, B. H., Jackson, I. & Fitz Gerald, J. D. High-temperature viscoelasticity of fine-grained polycrystalline olivine. Phys. Chem. Miner. 28, 641–664 (2001)

    ADS  CAS  Article  Google Scholar 

  14. 14

    Cliff, G. & Lorimer, G. W. The quantitative analysis of thin specimens. J. Microsc. 103, 203–207 (1975)

    Article  Google Scholar 

  15. 15

    Yan, Y., Chisholm, M. F., Duscher, G. & Pennycook, S. J. Atomic structure of a Ca-doped [001] tilt grain boundary in MgO. Electron Microsc. 47, 115–120 (1998)

    Google Scholar 

  16. 16

    Kingery, W. D. Plausible concepts necessary and sufficient for interpretation of ceramic grain-boundary phenomena, II. Solute segregation, grain-boundary diffusion, and general discussion. J. Am. Ceram. Soc. 57, 74–83 (1974)

    CAS  Article  Google Scholar 

  17. 17

    Beattie, P. Systematics and energetics of trace-element partitioning between olivine and silicate melts: Implications for the nature of mineral/melt partitioning. Chem. Geol. 117, 57–71 (1994)

    ADS  CAS  Article  Google Scholar 

  18. 18

    Blundy, J. & Wood, B. Prediction of crystal-melt partition coefficients from elastic moduli. Nature 372, 452–454 (1994)

    ADS  CAS  Article  Google Scholar 

  19. 19

    Brice, J. C. Some thermodynamic aspects of the growth of strained crystals. J. Cryst. Growth 28, 249–253 (1975)

    ADS  CAS  Article  Google Scholar 

  20. 20

    Isaak, D. G. High temperature elasticity of iron-bearing olivines. J. Geophys. Res. 97, 1871–1885 (1992)

    ADS  CAS  Article  Google Scholar 

  21. 21

    Takeuchi, Y., Yamanaka, T., Haga, N. & Hirana, M. in Material Science of the Earth's Interior (ed. Sunagawa, I.) 191–231 (Terra Scientific, Tokyo, 1984)

    Google Scholar 

  22. 22

    Purton, J. A., Allan, N. L., Blundy, J. D. & Wasserman, E. A. Isovalent trace element partitioning between minerals and melts: A computer simulation study. Geochim. Cosmochim. Acta 60, 4977–4987 (1996)

    ADS  CAS  Article  Google Scholar 

  23. 23

    Johnson, W. C. Grain boundary segregation in ceramics. Metall. Trans. A 8A, 1413–1422 (1977)

    ADS  CAS  Article  Google Scholar 

  24. 24

    Shervais, J. Thermal emplacement model for the alpine lherzolite massif at Balmuccia (Italy). J. Petrol. 20, 795–820 (1979)

    ADS  CAS  Article  Google Scholar 

  25. 25

    German, R. M. Formation of necklace microstructures during liquid phase sintering: model calculation. Int. J. Powder Metall. 22, 31–38 (1986)

    CAS  Google Scholar 

  26. 26

    Li, C.-W. & Kingery, W. D. in Advances in Ceramics (ed. Kingery, W. D.) 368–378 (American Ceramic Society, Columbus, 1985)

    Google Scholar 

  27. 27

    Frey, F. A. & Printz, M. Ultramafic inclusions from San Carlos, Arizona: Petrologic and geochemical data bearing on their petrogenesis. Earth Planet. Sci. Lett. 38, 129–176 (1978)

    ADS  CAS  Article  Google Scholar 

  28. 28

    Oxburgh, E. R. Petrological evidence for the presence of amphiboles in the upper mantle and its petrogenetic and geophysical implications. Geol. Mag. 101, 1–11 (1964)

    ADS  Article  Google Scholar 

  29. 29

    Wang, W. & Takahashi, E. J. Subsolidus and melting experiments of K-doped peridotite KLB-1 to 27 GPa: Its geophysical and geochemical implications. Geophys. Res. 105, 2855–2868 (2000)

    ADS  CAS  Article  Google Scholar 

  30. 30

    Watson, E. B., Brenan, J. M. & Baker, D. R. in Continental Mantle (ed. Menzies, M.) 111–125 (Oxford Univ. Press, Oxford, 1991)

    Google Scholar 

  31. 31

    Van Orman, J. A., Grove, T. L. & Shimizu, N. Uranium and thorium diffusion in diopside. Earth Planet. Sci. Lett. 160, 505–519 (1998)

    ADS  CAS  Article  Google Scholar 

  32. 32

    Hauri, E., Wagner, T. P. & Grove, T. L. Experimental and natural partitioning of Th, U, Pb and other trace elements between garnet, clinopyroxene and basaltic melts. Chem. Geol. 117, 149–166 (1994)

    ADS  CAS  Article  Google Scholar 

  33. 33

    Nakamura, M. & Watson, E. B. Experimental study of aqueous fluid infiltration into quartzite: implications for the kinetics of fluid redistribution and grain growth driven by interfacial energy reduction. Geofluids 1, 73–89 (2001)

    CAS  Article  Google Scholar 

  34. 34

    Maury, R. C., Defant, M. J. & Joron, J. L. Metasomatism of the sub-arc mantle inferred from trace elements in Philippine xenoliths. Nature 360, 661–663 (1992)

    ADS  CAS  Article  Google Scholar 

  35. 35

    Zanetti, A., Mazzucchelli, M., Rivalenti, G. & Vannucchi, R. The Finero phlogopite-peridotite massif: an example of subduction-related metasomatism. Contrib. Mineral. Petrol. 134, 107–122 (1999)

    ADS  CAS  Article  Google Scholar 

Download references

Acknowledgements

We thank M. Hirschmann and T. Morishita for discussions and M. Zimmerman for experimental assistance. T.H. acknowledges receipt of a JSPS research fellowship. This collaboration was performed under the ORNL SHaRE User Program and with support from the NSF.

Author information

Affiliations

Authors

Corresponding author

Correspondence to Takehiko Hiraga.

Ethics declarations

Competing interests

The authors declare that they have no competing financial interests.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Hiraga, T., Anderson, I. & Kohlstedt, D. Grain boundaries as reservoirs of incompatible elements in the Earth's mantle. Nature 427, 699–703 (2004). https://doi.org/10.1038/nature02259

Download citation

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.