Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

The origin of spinifex texture in komatiites

Nature volume 397, pages 691–694 (1999)Cite this article

Abstract

Komatiites are high-temperature, fluid, magnesium-rich lavas typically of Archaean age. A striking characteristic feature of such lavas is ‘spinifex’ texture—plate-like crystals of olivine ((Mg,Fe)2SiO4), millimetres to decimetres long, in a fine-grained matrix of spherulitic clinopyroxene (Ca(Mg,Fe,Al)(Si,Al)2O6), dendritic chromite ((Mg,Fe)(Cr,Al,Fe)2O4) and altered glass1,2,3,4. Sheaves of olivine crystals can reach lengths exceeding one metre, even in komatiite flows less than 10 metres thick, in sharp contrast to the millimetre-scale post-eruption growth of crystals in more common volcanic rocks. Crystal growth of this magnitude might be a consequence of the high content of the constituent elements of olivine in komatiitic liquid, combined with the low viscosity and high chemical diffusivity of the lavas. But flows lacking spinifex texture are not uncommon, and those with such texture often contain substantial amounts of submillimetre olivine crystals of unremarkable appearance, so chemical considerations alone do not appear to provide a sufficient explanation. Here we present evidence that spinifex texture develops as a result of large thermal gradients, coupled with conductive and radiative heat transfer within olivine crystals fixed in the cool upper layers of the lava flows. This mode of growth has features in common with the high-temperature techniques used to grow large synthetic single crystals, but is rarely considered in geological contexts.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Fractures within a komatiite lava tube, Pyke hill, Ontario.
Figure 2: Well-developed spinifex texture in a komatiite flow at Pyke hill.
Figure 3: Cross-section of plate-like olivine crystals (largely replaced by serpentine and magnetite) in a spinifex-textured komatiite.

Similar content being viewed by others

References

  1. Pyke, D. R., Naldrett, A. J. & Eckstrand, O. R. Archean ultramafic flows in Munro Township, Ontario. Bull. Geol. Soc. Am. 84, 955–978 (1973).

    Article  CAS  Google Scholar 

  2. Donaldson, C. H. in Komatiites (eds Arndt, N. T. &Nisbet, E. G.) 213–244 (Allen &Unwin, London, (1982).

    Google Scholar 

  3. Arndt, N. T. in Archean Crustal Evolution(ed. Condie, K. C.) 11–44 (Elsevier, Amsterdam, (1994).

    Book  Google Scholar 

  4. Shore, M. Cooling and Crystallization of Komatiite FlowsThesis, Univ. Ottawa (1996).

    Google Scholar 

  5. Huppert, H. E. & Sparks, R. S. J. Komatiites I: Eruption and flow. J. Petrol. 26, 694–725 (1985).

    Article  ADS  CAS  Google Scholar 

  6. Turner, J. S., Huppert, H. E. & Sparks, R. S. J. Komatiites II: Experimental and theoretical investigations of post-emplacement cooling and crystallization. J. Petrol. 27, 397–437 (1986).

    Article  ADS  CAS  Google Scholar 

  7. Nehlig, P. Fracture and permeability analysis in magma-hydrothermal transition zones in the Samail ophiolite (Oman). J. Geophys. Res. 99, 589–601 (1994).

    Article  ADS  Google Scholar 

  8. Davis, E. E., Chapman, D. S. & Forster, C. B. Observations concerning the vigor of hydrothermal circulation in young oceanic crust. J. Geophys. Res. 101, 2927–2942 (1996).

    Article  ADS  Google Scholar 

  9. Björnsson, H., Björnsson, S. & Sigurgeirsson, Th. Penetration of water into hot rock boundaries of magma at Grímsvötn. Nature 295, 580–581 (1982).

    Article  ADS  Google Scholar 

  10. Hardee, H. C., Dunn, J. C. & Hills, R. G. Probing the melt zone of Kilauea Iki lava lake, Kilauea volcano, Hawaii. Geophys. Res. Lett. 8, 1211–1214 (1981).

    Article  ADS  Google Scholar 

  11. Gudmundsson, M. T., Sigmundsson, F. & Björnsson, H. Ice–volcano interaction of the 1996 Gjálp subglacial eruption, Vatnajökull, Iceland. Nature 389, 954–957 (1997).

    Article  ADS  CAS  Google Scholar 

  12. Lowell, R. P. & Germanovich, L. N. On the temporal evolution of high-temperature hydrothermal systems at ocean ridge crests. J. Geophys. Res. 99, 565–575 (1994).

    Article  ADS  Google Scholar 

  13. Kinzler, R. T. & Grove, T. L. Crystallization and differentiation of Archean komatiite lavas from northeast Ontario: phase equilibrium and kinetic studies. Am. Mineral. 70, 40–51 (1985).

    CAS  Google Scholar 

  14. Parman, S. W., Dann, J. C., Grove, T. L. & de Wit, M. J. Emplacement conditions of komatiite magmas from the 3.49 Ga Komati Formation, Barberton Greenstone Belt, South Africa. Earth Planet. Science Lett. 150, 303–323 (1997).

    Article  ADS  CAS  Google Scholar 

  15. Donaldson, C. H. An experimental investigation of olivine morphology. Contrib. Mineral. Petrol. 57, 187–213 (1976).

    Article  ADS  CAS  Google Scholar 

  16. Donaldson, C. H. An experimental investigation of the delay in nucleation of olivine in mafic magmas. Contrib. Mineral. Petrol. 69, 21–32 (1979).

    Article  ADS  CAS  Google Scholar 

  17. Kanamori, H., Fujii, N. & Mizutani, H. Thermal diffusivity measurement of rock-forming minerals from 300° to 1100 °K. J. Geophys. Res. 73, 595–605 (1968).

    Article  ADS  CAS  Google Scholar 

  18. Fujisawa, H. et al. Thermal diffusivity of Mg2SiO4, Fe2SiO4, and NaCl at high pressures and temperatures. J. Geophys. Res. 73, 4727–4733 (1968).

    Article  ADS  CAS  Google Scholar 

  19. Schatz, J. F. & Simmons, G. Thermal conductivity of earth materials at high temperatures. J. Geophys. Res. 77, 6966–6983 (1972).

    Article  ADS  CAS  Google Scholar 

  20. Katsura, T. Thermal diffusivity of olivine under upper mantle conditions. Geophys. J. Int. 122, 63–69 (1995).

    Article  ADS  Google Scholar 

  21. Shankland, T. J., Nitsan, U. & Duba, A. G. Optical absorption and radiative heat transport in olivine at high temperature. J. Geophys. Res. 84, 1603–1610 (1979).

    Article  ADS  CAS  Google Scholar 

  22. Murase, T. & McBirney, A. R. Properties of some common igneous rocks and their melts at high temperatures. Bull. Geol. Soc. Am. 84, 3563–3592 (1973).

    Article  CAS  Google Scholar 

  23. Büttner, R., Zimanowski, B., Blumm, J. & Hagemann, L. Thermal conductivity of a volcanic rock material (olivine-melilitite) in the temperature range between 288 and 1470 K. J. Volcanol. Geotherm. Res. 80, 293–302 (1998).

    Article  ADS  Google Scholar 

  24. Shore, M. Comment on “Experimental determination of the thermal conductivity of molten CaMgSi2O6and the transport of heat through magmas”. J. Geophys. Res. 100, 22401–22402 (1995).

    Article  ADS  Google Scholar 

  25. Tiller, W. A. The Science of Crystallization: Macroscopic Phenomena and Defect Generation(Cambridge Univ. Press, (1991).

    Book  Google Scholar 

  26. Cockayne, B., Chesswas, M. & Gasson, D. B. Facetting and optical perfection in Czochralski grown garnets and rubies. J. Mater. Sci. 4, 450–456 (1969).

    Article  ADS  CAS  Google Scholar 

  27. Brandon, S. & Derby, J. J. Heat transfer in vertical Bridgman growth of oxides: effects of conduction, convection, and internal radiation. J. Cryst. Growth 121, 473–494 (1992).

    Article  ADS  CAS  Google Scholar 

  28. Tsukada, T., Kakinoki, K. & Hozawa, M. Effect of internal radiation within crystal and melt on Czochralski crystal growth of oxide. Int. J. Heat Mass Transfer 38, 2707–2714 (1995).

    Article  CAS  Google Scholar 

  29. Chai, M., Brown, J. M. & Slutsky, L. J. Thermal diffusivity of mantle minerals. Phys. Chem. Miner. 23, 470–475 (1996).

    Article  ADS  CAS  Google Scholar 

  30. Burns, R. G. Mineralogical Applications of Crystal Field Theory 2nd edn (Cambridge Univ. Press, (1993).

    Book  Google Scholar 

  31. Donaldson, C. H. Laboratory duplication of comb layering in the Rhum pluton. Mineral. Mag. 41, 323–336 (1977).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank A. M. Hofmeister for comments on the manuscript. This work was supported by NSERC.

Author information

Authors and Affiliations

  1. Ottawa-Carleton Geoscience Centre and Department of Earth Sciences, University of Ottawa, 140 Louis Pasteur, PO Box 450, Station A, Ottawa, K1N 6N5, Ontario, Canada

    Mark Shore & Anthony D. Fowler

Authors
  1. Mark Shore
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Anthony D. Fowler
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Anthony D. Fowler.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Shore, M., Fowler, A. The origin of spinifex texture in komatiites. Nature 397, 691–694 (1999). https://doi.org/10.1038/17794

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/17794

This article is cited by

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.

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing