Hydrogen sulphide release to surface waters at the Precambrian/Cambrian boundary

Abstract

Animal-like multicellular fossils appeared towards the end of the Precambrian, followed by a rapid increase in the abundance and diversity of fossils during the Early Cambrian period, an event also known as the ‘Cambrian explosion’1,2,3. Changes in the environmental conditions at the Precambrian/Cambrian transition (about 542 Myr ago) have been suggested as a possible explanation for this event, but are still a matter of debate1,2,3. Here we report molybdenum isotope signatures of black shales from two stratigraphically correlated sample sets with a depositional age of around 542 Myr. We find a transient molybdenum isotope signal immediately after the Precambrian/Cambrian transition. Using a box model of the oceanic molybdenum cycle, we find that intense upwelling of hydrogen sulphide-rich deep ocean water best explains the observed Early Cambrian molybdenum isotope signal. Our findings suggest that the Early Cambrian animal radiation may have been triggered by a major change in ocean circulation, terminating a long period during which the Proterozoic ocean was stratified, with sulphidic deep water.

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Figure 1: Merged Mo transient signal of Early Cambrian black shales from the Yangtze Platform and Oman basin.
Figure 2: The modelled Mo isotopic seawater signature in comparison with measured black shale isotope Mo data.

References

  1. 1

    Brasier, M. Background to the Cambrian Explosion. J. Geol. Soc. Lond. 149, 585–587 (1992)

  2. 2

    Grotzinger, J., Bowring, S., Saylor, B. & Kaufman, A. Biostratigraphic and geochronologic constraints on early animal evolution. Science 270, 598–604 (1995)

  3. 3

    Amthor, J. et al. Extinction of Cloudina and Namacalathus at the Precambrian-Cambrian boundary in Oman. Geology 31, 431–434 (2003)

  4. 4

    Siebert, C., Nägler, T., von Blanckenburg, F. & Kramers, J. Molybdenum isotope records as a potential new proxy for paleoceanography. Earth Planet. Sci. Lett. 211, 159–171 (2003)

  5. 5

    Siebert, C., Kramers, J., Meisel, P. & Nägler, T. PGE, Re-Os and Mo isotope systematics in Archean and early Proterozoic sedimentary systems as proxies for redox conditions of the early Earth. Geochim. Cosmochim. Acta 69, 1787–1801 (2005)

  6. 6

    Arnold, G., Anbar, A., Barling, J. & Lyons, T. Molybdenum isotope evidence for widespread anoxia in mid-Proterozoic oceans. Science 304, 87–90 (2004)

  7. 7

    Schröder, S. & Grotzinger, J. Evidence for anoxia at the Ediacaran-Cambrian boundary: The record of redox sensitive trace elements and rare earth elements in Oman. J. Geol. Soc. Lond. 164, 175–187 (2007)

  8. 8

    Amthor, J., Ramseyer, K., Faulkner, T. & Lucas, P. Stratigraphy and sedimentology of a chert reservoir at the Precambrian-Cambrian Boundary: the Al Shomou silicilyte, South Oman Salt Basin. GeoArabia 10, 89–122 (2005)

  9. 9

    Lehmann, B. et al. Highly metalliferous carbonaceous shale and Early Cambrian seawater. Geology 35, 403–406 (2007)

  10. 10

    Mao, J. et al. Re-Os dating of polymetallic Ni-Mo-PGE-Au mineralization in Lower Cambrian black shales of South China and its geological significance. Econ. Geol. 97, 1051–1061 (2002)

  11. 11

    Cao, S., Ma, D. & Pan, J. Stable isotopic geochemistry of organic carbon and pyrite sulfur from the Early Cambrian black shales in Northwestern Hunan China. Prog. Nat. Sci. 14, 181–187 (2004)

  12. 12

    Steiner, M., Wallis, E., Erdtmann, B.-D., Zhao, Y. & Yang, R. Submarine-hydrothermal exhalative ore layer in black shales from South China and associated fossils – insights into Lower Cambrian facies and bio-evolution. Palaeogeogr. Palaeoclimatol. Palaeoeocol 169, 165–191 (2001)

  13. 13

    Algeo, J. & Lyons, T. Mo-total organic carbon covariation in modern anoxic marine environments: Implications for analysis of paleoredox and paleohydrographic conditions. Paleoceanography 21, 1–23 (2006)

  14. 14

    Erickson, B. & Helz, G. Molybdenum(VI) speciation in sulfidic waters: Stability and lability of thiomolybdates. Geochim. Cosmochim. Acta 64, 1149–1158 (2000)

  15. 15

    Banerjee, D., Schidlowski, M., Siebert, F. & Brasier, M. Geochemical changes across the Proterozoic-Cambrian transition in the Durmala phosphorite mine section, Mussoorie Hills, Garhwal Himalaya, India. Palaeogeogr. Palaeoclimatol. Palaeoecol. 132, 183–194 (1997)

  16. 16

    Pan, J., Ma, D. & Cao, S. Trace element geochemistry of the Lower Cambrian black rock series from northwestern Hunan, South China. Prog. Nat. Sci. 14, 64–70 (2004)

  17. 17

    Siebert, C., McManus, J., Bice, A., Poulson, R. & Berelson, W. Molybdenum isotope signatures in continental margin marine sediments. Earth Planet. Sci. Lett. 241, 723–733 (2006)

  18. 18

    Nägler, T., Siebert, C., Lüschen, H. & Böttcher, M. Sedimentary Mo isotope record across the Holocene fresh-brackish water transition of the Black Sea. Chem. Geol. 219, 283–295 (2005)

  19. 19

    Maloof, A., Schrag, D., Crowley, J. & Bowring, S. An expanded record of Early Cambrian carbon cycling from the Anti-Atlas Margin, Morocco. Can. J. Earth Sci. 42, 2195–2216 (2005)

  20. 20

    Cowie, J., Brasier, M. (eds) The Precambrian-Cambrian Boundary (Clarendon, Oxford, UK, 1989)

  21. 21

    Shen, Y., Schidlowski, M. & Chu, X. Biogeochemical approach to understanding phosphogenic events of the terminal Proterozoic to Cambrian. Palaeogeogr. Palaeoclimatol. Palaeoecol. 158, 99–108 (2000)

  22. 22

    Kump, L., Pavlov, A. & Arthur, M. Massive release of hydrogen sulfide to the surface ocean and atmosphere during intervals of ocean anoxia. Geology 33, 397–400 (2005)

  23. 23

    Fike, D. A., Grotzinger, J. P., Pratt, L. M. & Summons, R. E. Oxidation of the Ediacaran Ocean. Nature 444, 744–747 (2006)

  24. 24

    Mort, H. et al. Phosphorus and the role of productivity and nutrient recycling during oceanic anoxic event 2. Geology 35, 483–486 (2007)

  25. 25

    Knoll, A. & Carroll, S. Early animal evolution: Emerging views from comparative biology and geology. Science 284, 2129–2137 (1999)

  26. 26

    Twitchett, R. The paleoclimatology, paleoecology and paleoenvironmental analysis of mass extinction events. Palaeogeogr. Palaeoclimatol. Palaeoecol. 131, 190–213 (2006)

  27. 27

    Kirschvink, J. & Raub, T. A methane fuse for the Cambrian explosion: carbon cycles and true polar wander. C.R. Geosci. 335, 65–78 (2003)

  28. 28

    Knoll, A., Bambach, R., Payne, J., Pruss, S. & Fischer, W. Paleophysiology and end-Permian mass extinction. Earth Planet. Sci. Lett. 256, 295–313 (2007)

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Acknowledgements

This work was financed by grants from the Swiss National Foundation to J.D.K. and T.F.N., from Deutsche Forschungsgemeinschaft to B.L., and from the German Academic Exchange Service to S.S. Thanks to Petroleum Development Oman LLC for financial and logistical support, and to J. Grotzinger and NASA for initial analytical work.

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Correspondence to Martin Wille.

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The file contains Supplementary Notes, Supplementary Tables 1-2, Supplementary Figures 1-2 and additional references. (PDF 456 kb)

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Wille, M., Nägler, T., Lehmann, B. et al. Hydrogen sulphide release to surface waters at the Precambrian/Cambrian boundary. Nature 453, 767–769 (2008) doi:10.1038/nature07072

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