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Atmospheric oxygenation three billion years ago


It is widely assumed that atmospheric oxygen concentrations remained persistently low (less than 10−5 times present levels) for about the first 2 billion years of Earth’s history1. The first long-term oxygenation of the atmosphere is thought to have taken place around 2.3 billion years ago, during the Great Oxidation Event2,3. Geochemical indications of transient atmospheric oxygenation, however, date back to 2.6–2.7 billion years ago4,5,6. Here we examine the distribution of chromium isotopes and redox-sensitive metals in the approximately 3-billion-year-old Nsuze palaeosol and in the near-contemporaneous Ijzermyn iron formation from the Pongola Supergroup, South Africa. We find extensive mobilization of redox-sensitive elements through oxidative weathering. Furthermore, using our data we compute a best minimum estimate for atmospheric oxygen concentrations at that time of 3 × 10−4 times present levels. Overall, our findings suggest that there were appreciable levels of atmospheric oxygen about 3 billion years ago, more than 600 million years before the Great Oxidation Event and some 300–400 million years earlier than previous indications for Earth surface oxygenation.

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Figure 1: Geographical location and stratigraphy.
Figure 2: Geochemical profiles and lithologies of the Nsuze palaeosol.
Figure 3: Geochemical profiles of the IIF.


  1. Canfield, D. E. The early history of atmospheric oxygen: homage to Robert A. Garrels. Annu. Rev. Earth Planet. Sci. 33, 1–36 (2005)

    Article  CAS  ADS  Google Scholar 

  2. Holland, H. D. Volcanic gases, black smokers, and the Great Oxidation Event. Geochim. Cosmochim. Acta 66, 3811–3826 (2002)

    CAS  ADS  Google Scholar 

  3. Guo, Q. J. et al. Reconstructing Earth’s surface oxidation across the Archean-Proterozoic transition. Geology 37, 399–402 (2009)

    Article  ADS  Google Scholar 

  4. Wille, M. et al. Evidence for a gradual rise of oxygen between 2.6 and 2.5 Ga from Mo isotopes and Re-PGE signatures in shales. Geochim. Cosmochim. Acta 71, 2417–2435 (2007)

    Article  CAS  ADS  Google Scholar 

  5. Anbar, A. D. et al. A whiff of oxygen before the Great Oxidation Event? Science 317, 1903–1906 (2007)

    Article  CAS  ADS  Google Scholar 

  6. Frei, R., Gaucher, C., Poulton, S. W. & Canfield, D. E. Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes. Nature 461, 250–253 (2009)

    Article  CAS  ADS  Google Scholar 

  7. Beukes, N. J. & Cairncross, B. A lithostratigraphic sedimentological reference profile for the Late Archean Mozaan Group, Pongola Sequence: application to sequence stratigraphy and correlation with the Witwatersrand Supergroup. S. Afr. J. Geol. 94, 44–69 (1991)

    Google Scholar 

  8. Mukasa, S. B., Wilson, A. H. & Young, K. R. Geochronological constraints on the magmatic and tectonic development of the Pongola Supergroup (Central Region), South Africa. Precambr. Res. 224, 268–286 (2013)

    Article  CAS  ADS  Google Scholar 

  9. Alexander, B. W., Bau, M., Andersson, P. & Dulski, P. Continentally-derived solutes in shallow Archean seawater: Rare earth element and Nd isotope evidence in iron formation from the 2.9 Ga Pongola Supergroup, South Africa. Geochim. Cosmochim. Acta 72, 378–394 (2008)

    Article  CAS  ADS  Google Scholar 

  10. Nhleko, N. The Pongola Supergroup in Swaziland. PhD thesis, Rand Afrikaans Univ. (2003)

  11. Frei, R. & Polat, A. Chromium isotope fractionation during oxidative weathering—Implications from the study of a Paleoproterozoic (ca. 1.9 Ga) paleosol, Schreiber Beach, Ontario, Canada. Precambr. Res. 224, 434–453 (2013)

    Article  CAS  ADS  Google Scholar 

  12. Crowe, S. A. et al. Oxidative weathering fractionates chromium isotopes. Mineral. Mag. 75, 706 (2011)

    Google Scholar 

  13. Ellis, A. S., Johnson, T. M. & Bullen, T. D. Chromium isotopes and the fate of hexavalent chromium in the environment. Science 295, 2060–2062 (2002)

    Article  CAS  ADS  Google Scholar 

  14. Zink, S., Schoenberg, R. & Staubwasser, M. Isotopic fractionation and reaction kinetics between Cr(III) and Cr(VI) in aqueous media. Geochim. Cosmochim. Acta 74, 5729–5745 (2010)

    Article  CAS  ADS  Google Scholar 

  15. Konhauser, K. O. et al. Aerobic bacterial pyrite oxidation and acid rock drainage during the Great Oxidation Event. Nature 478, 369–373 (2011)

    Article  CAS  ADS  Google Scholar 

  16. Eary, L. E. & Rai, D. Kinetics of chromium (III) oxidation to chromium (VI) by reaction with manganese dioxide. Environ. Sci. Technol. 21, 1187–1193 (1987)

    Article  ADS  Google Scholar 

  17. Oze, C., Bird, D. K. & Fendorf, S. Genesis of hexavalent chromium from natural sources in soil and groundwater. Proc. Natl Acad. Sci. USA 104, 6544–6549 (2007)

    Article  CAS  ADS  Google Scholar 

  18. Tipping, E. Temperature dependence of Mn(II) oxidation in lakewaters: a test of biological involvement. Geochim. Cosmochim. Acta 48, 1353–1356 (1984)

    Article  CAS  ADS  Google Scholar 

  19. Grandstaff, D. E. Origin of uraniferous conglomerates at Elliot Lake, Canada, and Witwatersrand, South Africa: implications for oxygen in the Precambrian atmosphere. Precambr. Res. 13, 1–26 (1980)

    Article  CAS  ADS  Google Scholar 

  20. Maynard, J. B. Chemistry of modern soils as a guide to interpreting Precambrian paleosols. J. Geol. 100, 279–289 (1992)

    Article  ADS  Google Scholar 

  21. Ohmoto, H. Evidence in pre–2.2 Ga paleosols for the early evolution of atmospheric oxygen and terrestrial biota. Geology 24, 1135–1138 (1996)

    Article  CAS  ADS  Google Scholar 

  22. Schoenberg, R., Zink, S., Staubwasser, M. & von Blanckenburg, F. The stable Cr isotope inventory of solid Earth reservoirs determined by double spike MC-ICP-MS. Chem. Geol. 249, 294–306 (2008)

    Article  CAS  ADS  Google Scholar 

  23. Condie, K. C. Chemical composition and evolution of the upper continental crust: contrasting results from surface samples and shales. Chem. Geol. 104, 1–37 (1993)

    Article  CAS  ADS  Google Scholar 

  24. Eary, L. E. & Rai, D. Kinetics of chromate reduction by ferrous ions derived from hematite and biotite at 25 degrees C. Am. J. Sci. 289, 180–213 (1989)

    Article  CAS  ADS  Google Scholar 

  25. Sass, B. M. & Rai, D. Solubility of amorphous chromium(III)-iron(III) hydroxide solid-solutions. Inorg. Chem. 26, 2228–2232 (1987)

    Article  CAS  Google Scholar 

  26. Farquhar, J. et al. Isotopic evidence for Mesoarchaean anoxia and changing atmospheric sulphur chemistry. Nature 449, 706–709 (2007)

    Article  CAS  ADS  Google Scholar 

  27. Guy, B. M. et al. A multiple sulfur and organic carbon isotope record from non-conglomeratic sedimentary rocks of the Mesoarchean Witwatersrand Supergroup, South Africa. Precambr. Res. 216–219, 208–231 (2012)

    Article  ADS  Google Scholar 

  28. Pavlov, A. A. & Kasting, J. F. Mass-independent fractionation of sulfur isotopes in Archean sediments: strong evidence for an anoxic Archean atmosphere. Astrobiology 2, 27–41 (2002)

    Article  CAS  ADS  Google Scholar 

  29. Canfield, D. E., Habicht, K. S. & Thamdrup, B. The Archean sulfur cycle and the early history of atmospheric oxygen. Science 288, 658–661 (2000)

    Article  CAS  ADS  Google Scholar 

  30. Haqq-Misra, J., Kasting, J. F. & Lee, S. Availability of O2 and H2O2 on pre-photosynthetic Earth. Astrobiology 11, 293–302 (2011)

    Article  CAS  ADS  Google Scholar 

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N. Planavsky, R. Schoenberg, S. Poulton, A. Basu, C. Jones, H. Tsikos, A. Mucci, A. O’Neill and T. Dahl are thanked for suggestions. T. Larsen, C. N. Jensen, T. Leeper and P. Søholt are acknowledged for technical support. Funding to S.A.C. was provided by an Agouron Institute Geobiology Fellowship and an NSERC PDF. Additional funding was from the Danish National Research Foundation (grant no. DNRF53), the Danish Agency for Science, Technology, and Innovation, the European Research Council and the National Research Foundation in Pretoria. The palaeosol drill core was made available by Ian Frith of AngloGold Ashanti Exploration (SA), from their core store in Carltonville, South Africa.

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S.A.C., N.J.B. and L.N.D. had the idea for the study; samples were provided by N.J.B. and M.B.; Cr isotope measurements were made by L.N.D.; other geochemical analyses were performed by L.N.D., S.A.C., N.J.B. and S.J.K.; S.A.C., L.N.D. and D.E.C. produced the manuscript with significant contributions from all authors.

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Correspondence to Sean A. Crowe.

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The authors declare no competing financial interests.

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Crowe, S., Døssing, L., Beukes, N. et al. Atmospheric oxygenation three billion years ago. Nature 501, 535–538 (2013).

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