Brunhes–Matuyama reversal

The Brunhes–Matuyama reversal, named after Bernard Brunhes and Motonori Matuyama, was a geologic event, approximately 781,000 years ago, when the Earth's magnetic field last underwent reversal.[1][2] The reversal may have occurred slowly over several thousand years, or more quickly; opinions vary.[3][4][5] The apparent duration at any particular location varied from 1,200 to 10,000 years depending on geomagnetic latitude and local effects of non-dipole components of the Earth's field during the transition.[6]

The Brunhes-Matuyama reversal is a Global Boundary Stratotype Section and Point (GBSSP), selected by the International Commission on Stratigraphy as a marker for the beginning of the Middle Pleistocene, also known as the Ionian Stage.[7] It is useful in dating ocean sediment cores and subaerially erupted volcanics.

See also

References

  1. Gradstein, Felix M.; Ogg, James G.; Smith, Alan G., eds. (2004). A Geological Time Scale 2004 (3rd ed.). Cambridge University Press: Cambridge University Press. p. 28. ISBN 9780521786737.
  2. "Global chronostratigraphical correlation table for the last 2.7 million years". International Commission on Stratigraphy. Retrieved 31 March 2014.
  3. Witze, Alexandra (Sep 2, 2010). "Geomagnetic field flip-flops in a flash". ScienceNews. Retrieved 3 September 2010.
  4. Coe, R.S.; Prévot, M.; Camps, P. (20 April 1995). "New evidence for extraordinarily rapid change of the geomagnetic field during a reversal". Nature 374 (6524): 687. Bibcode:1995Natur.374..687C. doi:10.1038/374687a0.
  5. Bogue, S. W.; Glen, J. M. G. (2010). "Very rapid geomagnetic field change recorded by the partial remagnetization of a lava flow". Geophysical Research Letters 37: L21308. Bibcode:2010GeoRL..3721308B. doi:10.1029/2010GL044286.
  6. Bradford M. Clement (8 April 2004). "Dependence of the duration of geomagnetic polarity reversals on site latitude". Nature 428 (6983): 637–40. Bibcode:2004Natur.428..637C. doi:10.1038/nature02459. PMID 15071591.
  7. "Global Boundary Stratotype Section and Point". International Commission of Stratigraphy. Retrieved 31 March 2014.

Further reading