The magnetic reversal record is not periodic

  title={The magnetic reversal record is not periodic},
  author={Timothy M. Lutz},
  • T. Lutz
  • Published 1 October 1985
  • Biology
  • Nature
Statistical analysis of one version of the magnetic reversal record suggests that the frequency of reversals has changed cyclically with a period of 30 Myr starting at least 165 Myr ago. But factors other than periodicity affect the analysis used and here I show that there is no compelling evidence for periodicity in the reversal record. The results of essentially identical analyses that have been applied to other geolocial data should also be re-evaluated. 

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  • D. RaupJ. Sepkoski
  • Geography, Environmental Science
    Proceedings of the National Academy of Sciences of the United States of America
  • 1984
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