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.

Sanidine spherules at the Cretaceous–Tertiary boundary indicate a large impact event

Abstract

The hypothesis that a catastrophic impact of an extraterrestrial body caused the terminal Cretaceous mass extinctions of dinosaurs, planktonic foraminfera and other species is now accepted as respectable following the discovery of a worldwide iridium enrichment in the Cretaceous–Tertiary (K–T) boundary clay1–5. In the basal lamina of the K–T boundary clay of Caravaca (Spain)7 numerous spherules were discovered composed of finely crystallized, almost pure K-feldspar in the structural state of high sanidine. It is concluded here that these spherules solidified from a melt and were probably derived from the impacting body. This poses problems as high K-values are not reported from bulk analyses of meteorites6. The K-feldspar phenocrysts reported in some iron meteorites23 suggest the body may have been a metal–sulphide–silicate planetesimal. A cometary body is suggested as an alternative.

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

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

References

  1. Alvarez, L. W. et al. Science 208, 367–371 (1980).

    Article  Google Scholar 

  2. Smit, J. & Hertogen, J. Nature 285, 198–200 (1980).

    Article  CAS  ADS  Google Scholar 

  3. Ganapathy, R. Science 209, 921–923 (1980).

    Article  CAS  ADS  Google Scholar 

  4. Kyte, F. T. et al. Nature 288, 651–656 (1980).

    Article  CAS  ADS  Google Scholar 

  5. Hsü, K. J. Nature 285, 201–203 (1980).

    Article  ADS  Google Scholar 

  6. Mason, B. Handbook of Elemental Abundances in Meteorites (Gordon and Breach, New York, 1973).

    Google Scholar 

  7. Smit, J. Proc. Kon. Ned. Akad. Wet. 80, B, 280–301 (1977).

    Google Scholar 

  8. Borg, I. Y. & Smith, D. K. Geol. Soc. Am. Mem. 122 (1969).

  9. Palme, H. et al. Proc. 10th Lunar Sci. Conf. 2465–2492 (1979).

  10. Lambert, P. Impact and Explosion Cratering, 449–460 (Pergamon, Oxford, 1977).

    Google Scholar 

  11. Smith, J. V. Feldspar Minerals (Springer, New York, 1974).

    Google Scholar 

  12. Van Hinte, J. E. Bull. Am. Ass. petrol. Geol. 60, 498–516 (1976).

    Google Scholar 

  13. Lofgren, G. in Physics of Magmatic Processes, 487–551 (Princeton University Press, 1980).

    Google Scholar 

  14. Kastner, M. Am. Miner. 56, 7–8, 1403–1442 (1971).

    Google Scholar 

  15. Baskin, Y. J. Geol. 64, 132–155 (1956).

    Article  CAS  ADS  Google Scholar 

  16. Woodard, H. H. J. Geol. 80, 323–332 (1972).

    Article  CAS  ADS  Google Scholar 

  17. Brus, Z. & Rieder, M. Acta univ. carol. 1, 37–45 (1975).

    Google Scholar 

  18. Lancelot et al. Init. Rep. DSDP Leg 11, 901–950 (1972).

    Google Scholar 

  19. Wright, T. L. Am. Miner. 53, 88–104 (1968).

    CAS  Google Scholar 

  20. O'Keefe, J. A. (ed.) Tektites (University of Chicago Press, 1963).

  21. Parfenova, O. V. & Yakovlev, O. I. Impact and Explosion Cratering, 843–859 (Pergamon Oxford, 1977).

    Google Scholar 

  22. Blanchard, M. B. et al. Earth planet. Sci. Lett. 46, 178–190 (1980).

    Article  CAS  ADS  Google Scholar 

  23. Wasserburg, G. J. et al. Science 161, 684–687 (1968).

    Article  CAS  ADS  Google Scholar 

  24. Bandhari, N. & Shah, V. G. Proc. Ind. nat. Sci. Acad. A 45/3, 199–200 (1977).

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Smit, J., Klaver, G. Sanidine spherules at the Cretaceous–Tertiary boundary indicate a large impact event. Nature 292, 47–49 (1981). https://doi.org/10.1038/292047a0

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/292047a0

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

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