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.

A new model for Proterozoic ocean chemistry

Abstract

There was a significant oxidation of the Earth's surface around 2 billion years ago (2 Gyr)1,2,3,4. Direct evidence for this oxidation comes, mostly, from geological records of the redox-sensitive elements Fe and U reflecting the conditions prevailing during weathering1,2,3. The oxidation event was probably driven by an increased input of oxygen to the atmosphere arising from an increased sedimentary burial of organic matter between 2.3 and 2.0 Gyr5. This episode was postdated by the final large precipitation of banded iron formations around 1.8 Gyr1,2. It is generally believed that banded iron formations precipitated from an ocean whose bottom waters contained significant concentrations of dissolved ferrous iron, and that this sedimentation process terminated when aerobic bottom waters developed, oxidizing the iron and thus removing it from solution1,2. In contrast, I argue here that anoxic bottom waters probably persisted until well after the deposition of banded iron formations ceased; I also propose that sulphide, rather than oxygen, was responsible for removing iron from deep ocean water. The sulphur-isotope record supports this hypothesis as it indicates increasing concentrations of oceanic sulphate, starting around 2.3 Gyr6, leading to increasing rates of sulphide production by sulphate reduction. The increase in sulphide production became sufficient, around 1.8 Gyr, to precipitate the total flux of iron into the oceans. I suggest that aerobic deep-ocean waters did not develop until the Neoproterozoic era (1.0 to 0.54 Gyr), in association with a second large oxidation of the Earth's surface. This new model is consistent with the emerging view of Precambrian sulphur geochemistry and the chemical events leading to the evolution of animals, and it is fully testable by detailed geochemical analyses of preserved deep-water marine sediments.

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

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: The relationship between deep-water oxygen concentration (O2(d)) and phosphorus availability (represented by [P(d) − P.(f)]) in the oceans.
Figure 2: The isotope composition of sedimentary sulphides of probable biological origin over geological time.

References

  1. Cloud, P. E. J Aworking model of the primitive Earth. Am. J. Sci. 272, 537–548 (1972).

    Google Scholar 

  2. Holland, H. D. The Chemical Evolution of the Atmosphere and Oceans (Princeton Univ. Press, Princeton, (1984)).

    Google Scholar 

  3. Holland, H. D. & Beukes, N. Apaleoweathering profile from Griqualand West, South Africa: evidence for a dramatic rise in atmospheric oxygen between 2.2 and 1.9 bybp. Am. J. Sci. 290-A, 1–34 (1990).

    Google Scholar 

  4. Des Marais, D. J., Strauss, H. Summons, R. E. & Hayes, J. M. Carbon isotope evidence for the stepwise oxidation of the Proterozoic environment. Nature 359, 605–609 (1992).

    Article  ADS  CAS  Google Scholar 

  5. Karhu, J. A. & Holland, H. D. Carbon isotopes and the rise of atmospheric oxygen. Geology 24, 867–870 (1996).

    Google Scholar 

  6. Hayes, J. M., Lambert, I. B. & Strauss, H. in The Proterozoic Biosphere: A Multidisciplinary Study (eds Schoff, J. W. & Klein, C.) 129–134 (Cambridge Univ. Press, (1992)).

    Google Scholar 

  7. Sarmiento, J. L., Herbert, T. D. & Toggweiler, J. R. Causes of anoxia in the world ocean. Glob. Biogeochem. Cycles 2, 115–128 (1988).

    Google Scholar 

  8. Ridge/vents Workshop Group. In Global Impact of Submarine Hydrothermal Processes (eds Kadko, D., Baker, E., Alt, J. & Baross, J. 4–15 (NSF RIDGE Initiative and NOAA Vents Program, (1994)).

  9. Shaffer, G. Biogeochemical cycling in the global ocean 2. New production, Redfield ratios, and remineralization in the organic pump. J. Geophys. Res. 101, 3723–3745 (1996).

    Google Scholar 

  10. Emerson, S., Quay, P. D., Stump, C. & Schudlich, R. Chemical tracers of productivity and respiration in the subtropical Pacific Ocean. J. Geophys. Res. 100, 15873–15887 (1995).

    Google Scholar 

  11. Knoll, A. H. in Origin and Early Evolution of the Metazoa (eds Lipps, J. H. & Signor, P. W.) 53–84 (Plenum, New York, (1992)).

    Book  Google Scholar 

  12. Canfield, D. E. & Teske, A. Late proterozoic rise in atmospheric oxygen concentration inferred from phylogenetic and sulphur-isotope studies. Nature 382, 127–132 (1996).

    Article  ADS  CAS  Google Scholar 

  13. Berkner, L. V. & Marshall, L. C. On the origin and rise of oxygen concentration in the Earth's atmosphere. J. Atmos. Res. 22, 225–261 (1965).

    Google Scholar 

  14. Knoll, A. H., Hayes, J. M., Kaufman, A. J., Swett, K. & Lambert, I. B. Secular variation in carbon isotope ratios from Upper Proterozoic successions of Svalbard and East Greenland. Nature 321, 832–838 (1986).

    Article  ADS  CAS  Google Scholar 

  15. Cameron, E. M. Sulphate and sulphate reduction in early Precambrian oceans. Nature 296, 145–148 (1982).

    Article  ADS  CAS  Google Scholar 

  16. Harrison, A. G. & Thode, H. G. Mechanisms of the bacterial reduction of sulfate from isotope fractionation studies. Trans. Faraday Soc. 53, 84–92 (1958).

    Google Scholar 

  17. Ohmoto, H., Kakegawa, T. & Lowe, D. R. 3.4-billion-year-old biogenic pyrites from Barberton, South Africa: Sulfur isotope evidence. Science 262, 555–557 (1993).

    Google Scholar 

  18. Habicht, K. S. & Canfield, D. E. Sulphur isotope fractionation in modern microbial mats and the evolution of the sulphur cycle. Nature 382, 342–343 (1996).

    Article  ADS  CAS  Google Scholar 

  19. van Cappellen, P. & Wang, Y. in Metal Contaminated Sediments (ed. Allen, H. E.) 21–64 (Ann Arbor, Chelsea, Michigan, (1995)).

    Google Scholar 

  20. Berner, R. A. & Raiswell, R. Burial or organic carbon and pyrite sulfur in sediments over geologic time. Geochim. Cosmochim. Acta 47, 855–862 (1983).

    Google Scholar 

  21. Beukes, N. J. & Klein, C. in The Proterozoic Biosphere: A Multidisciplinary Study (eds Schoff, J. W. & Klein, C.) 147–151 (Cambridge Univ. Press, (1992)).

    Google Scholar 

  22. Logan, G. A., Hayes, J. M., Hieshima, G. B. & Summons, R. E. Terminal Proterozoic re-organization of biogeochemical cycles. Nature 376, 53–56 (1995).

    Article  ADS  CAS  Google Scholar 

  23. Schieber, J. Anomalous iron distribution in shales as a manifestation of “non-clastic iron” supply to sedimentary basins: relevance for pyritic shales, base-metal mineralization, and oolitic ironstone deposits. Mineral. Deposita 30, 294–302 (1995).

    Google Scholar 

  24. Canfield, D. E., Lyons, T. W. & Raiswell, R. Amodel for iron deposition to euxinic Black Sea sediments. Am. J. Sci. 296, 818–834 (1996).

    Google Scholar 

  25. Raiswell, R. & Canfield, D. E. Sources of iron for pyrite formation in marine sediments. Am. J. Sci. 298, 219–245 (1998).

    Google Scholar 

  26. Imbus, S. W., Macko, S., Elmore, R. D. & Engel, M. Stable isotope (C,S,N) and molecular studies on the Precambrian Nonesuch Shale (Wisconsin–Michigan, USA): evidence for differential preservation rates, depositional environment and hydrothermal influence. Chem. Geol. 101, 255–281 (1992).

    Google Scholar 

  27. Jackson, M. J. & Raiswell, R. Sedimentology and carbon–sulphur geochemistry of the Velkerri Formation, a mid-Proterozoic potential oil source in northern Australia. Precambr. Res. 54, 81–108 (1991).

    Google Scholar 

  28. Vidal, G. & Nystuen, J. P. Micropaleontology, depositional environment, and biostratigraphy of the Upper Proterozoic Hedmark Group, Southern Norway. Am. J. Sci. 290-A, 170–211 (1990).

    Google Scholar 

  29. Canfield, D. E. The geochemistry of river particulates from the continental United States: major elements. Geochim. Cosmochim. Acta 61, 3349–3365 (1997).

    Google Scholar 

  30. Milliman, J. D. & Syvitski, J. P. M. Geomorphic/tectonic control of sediment discharge to the ocean: the importance of mountainous rivers. J. Geol. 100, 525–544 (1992).

    Google Scholar 

Download references

Acknowledgements

I thank J. Hayes, B. Thamdrup, D. Des Marais and A. Knoll for comments on the manuscript. Financial support came from the Danish National Science Research Council (SNF) and the Danish National Research Foundation (Danmarks Grundforskningsfond). This Letter is dedicated to the memory of H. Jannasch.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to D. E. Canfield.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Canfield, D. A new model for Proterozoic ocean chemistry. Nature 396, 450–453 (1998). https://doi.org/10.1038/24839

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/24839

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