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Earth science

Geomagnetism under scrutiny

Nature volume 485, pages 319–320 (2012)Cite this article

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New calculations show that the electrical resistance of Earth's liquid-iron core is lower than had been thought. The results prompt a reassessment of how the planet's magnetic field has been generated and maintained over time. See Letter p.355

Fluid flow in Earth's liquid-iron core sustains the planet's magnetic field against persistent losses due to the electrical resistance of liquid iron. The battle between generation and loss of the magnetic field suggests that a decrease in electrical resistance would tilt the balance in favour of generation. Surprisingly, the opposite may be closer to the truth. On page 355 of this issue, Pozzo et al.1 use a mathematical method called density functional theory to predict the electrical resistance of liquid-iron alloys at the high pressures and temperatures found in Earth's core. Their values are only two to three times lower than previous estimates2, but this change is large enough to affect our understanding of the dynamics and evolution of Earth's interior.

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Figure 1: Temperature profile of Earth's interior.

References

  1. Pozzo, M., Davies, C., Gubbins, D. & Alfè, D. Nature 485, 355–358 (2012).

    Article  ADS  CAS  Google Scholar 

  2. Stacey, F. D. & Anderson, O. L. Phys. Earth Planet. Inter. 124, 153–162 (2001).

    Article  ADS  CAS  Google Scholar 

  3. Christensen, U. R. & Aubert, J. Geophys. J. Int. 166, 97–114 (2006).

    Article  ADS  Google Scholar 

  4. Gubbins, D., Thomson, C. J. & Whaler, K. A. Geophys. J. R. Astron. Soc. 68, 241–251 (1982).

    Article  ADS  Google Scholar 

  5. Lay, T., Hernlund, J. & Buffett, B. A. Nature Geosci. 1, 25–32 (2008).

    Article  ADS  CAS  Google Scholar 

  6. Gillet, N., Schaeffer, N. & Jault, D. Phys. Earth Planet. Inter. 187, 380–390 (2011).

    Article  ADS  Google Scholar 

  7. Corgne, A., Keshav, S., Fei, Y. W. & McDonough, W. F. Earth Planet. Sci. Lett. 256, 567–576 (2007).

    Article  ADS  CAS  Google Scholar 

  8. de Koker, N., Steinle-Neumann, G. & Vlček, V. Proc. Natl Acad. Sci. USA 109, 4070–4073 (2012).

    Article  ADS  CAS  Google Scholar 

  9. Hirose, K. et al. Mineral. Mag. 75, 1027 (2011).

    Google Scholar 

  10. Nakagawa, T. & Tackley, P. J. Geochem. Geophys. Geosyst. 11, Q06001 (2010).

    Article  ADS  Google Scholar 

  11. Buffett, B. A. Geophys. J. Int. 179, 711–719 (2009).

    Article  ADS  Google Scholar 

  12. Monnereau, M. et al. Science 328, 1014–1017 (2010).

    Article  ADS  CAS  Google Scholar 

  13. Alboussière, T., Deguen, R. & Melzani, M. Nature 466, 744–747 (2010).

    Article  ADS  Google Scholar 

  14. Sun, X. & Song, X. Phys. Earth Planet. Inter. 167, 53–70 (2008).

    Article  ADS  Google Scholar 

Download references

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  1. Bruce Buffett is in the Department of Earth and Planetary Science, University of California, Berkeley, Berkeley, California 94720-4767, USA.,

    Bruce Buffett

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  1. Bruce Buffett
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Buffett, B. Geomagnetism under scrutiny. Nature 485, 319–320 (2012). https://doi.org/10.1038/485319a

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