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Earth science

Time of reversal

At intervals, the polarity of the Earth's magnetic field reverses. The timescale for this reversal is unclear — in fact, it seems to depend on the latitude of the site from which the geological data are extracted.

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  1. Clement, B. M. Nature 428, 637–640 (2004).

    CAS  Article  ADS  Google Scholar 

  2. Kono, M. & Roberts, P. Rev. Geophys. 40, 1–53 (2002).

    Article  Google Scholar 

  3. Hulot, G. et al. Nature 416, 620–623 (2002).

    CAS  Article  ADS  Google Scholar 

  4. Merrill, R. T. & McFadden, P. L. Rev. Geophys. 37, 201–226 (1999).

    Article  ADS  Google Scholar 

  5. Merrill, R. T. & McFadden, P. L. J. Geophys. Res. 93, 11589–11597 (1988).

    Article  ADS  Google Scholar 

  6. Li, J., Sato, T. & Kageyama, A. Science 295, 1887–1890 (2002).

    CAS  Article  ADS  Google Scholar 

  7. Christensen, U. R. & Olson, P. Phys. Earth Planet. Inter. 138, 39–54 (2003).

    Article  ADS  Google Scholar 

  8. Bullard, E. C. & Gellman, H. Phil. Trans. R. Soc. Lond. A 247, 213–255 (1954).

    Article  ADS  Google Scholar 

  9. Roberts, P. in Mathematical Problems in the Geophysical Sciences (ed. Reid, W. H.) 129–206 (Am. Math. Soc., Providence, Rhode Island, 1971).

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Merrill, R. Time of reversal. Nature 428, 608–609 (2004).

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