Skip to main content


We’d like to understand how you use our websites in order to improve them. Register your interest.

A Brunhes-Matuyama polarity transition record from anoxic sediments in the South Atlantic (Ocean Drilling Program Hole 1082C)


A paleomagnetic study was performed on Hole 1082C sediment cores taken during the Ocean Drilling Program (ODP) Leg 175 in the South Atlantic in order to obtain a high-resolution Brunhes-Matuyama (B/M) polarity transition record. An average sedimentation rate was as high as 10 cm/kyr. The cores consist of strongly anoxic sediments, which is common for the areas of large material supply. Anoxic sediments, which are geochemically quite active, were considered to be unsuitable for studies on detailed behavior of the geomagnetic field such as polarity transitions. For global site distribution, however, it is necessary to make efforts to retrieve paleomagnetic records from such sediments. A continuous record of directional changes around the transition was obtained from U-channel samples after cleaning by stepwise alternating-field (AF) demagnetization. Consistency of the record was checked using discrete samples taken from the other half of the cores. The coring-induced magnetic overprint of radial-inward direction, which has often been reported from ODP piston-cores, was negligibly small in our cores. Relative paleointensity variation was estimated from remanent intensities of the discrete samples normalized by artificial remanences. Our record shows following features of the B/M transition similar to those already reported by previous studies. A zone of large directional fluctuations with low paleointensities occurs just before the main transition (788 to 795 ka based on the oxygen-isotope stratigraphy), which would correspond to the “precursor” of Hartl and Tauxe (1996). The virtual geomagnetic poles (VGPs) at the precursor lie along the so-called preferred longitudinal bands over the north-south Americas and Australia-east Asia. After the main transition from the reversed to normal polarity, VGPs stayed in the middle-to-high latitudes over the North America with an intermediate paleointensity for about 5 kyrs, and then moved in the vicinity of the North Pole with full recovery of intensity. Such behavior was reported by Oda et al. (2000). These similarities suggest that the anoxic sediments at Site 1082 could record the behavior of the geomagnetic field rather faithfully, although the remanence may be of chemical origin.


  1. Barton, C. E. and P. L. McFadden, Inclination shallowing and preferred transitional VGP paths, Earth Planet. Sci. Lett., 140, 147–157, 1996.

  2. Bassinot, F. C., L. D. Labeyrie, E. Vincent, X. Quidelleur, N. J. Shackleton, and Y. Lancelot, The astronomical theory of climate and the age of the Brunhes-Matuyama magnetic reversal, Earth Planet. Sci. Lett., 126, 91–108, 1994.

  3. Bloemendal, J., J. W. King, F. R. Hall, and S.-J. Doh, Rock magnetism of Late Neogene and Pleistocene deep-sea sediments: relationship to sediment source, diagenetic processes, and sediment lithology, J. Geophys. Res., 97, 4361–4375, 1992.

  4. Cande, S. C. and D. V. Kent, A new geomagnetic polarity time scale for the Late Cretaceous and Cenozoic, J. Geophys. Res., 97, 13917–13951, 1992.

  5. Channell, J. E. T. and B. Lehman, The last two geomagnetic polarity reversals recorded in high-deposition-rate sediment drifts, Nature, 389, 712–715, 1997.

  6. Clement, B. M., Geographical distribution of transitional VGPs: evidence for non-zonal equatorial symmetry during the Matuyama-Brunhes geomagnetic reversal, Earth Planet. Sci. Lett., 104, 48–58, 1991.

  7. Constable, C., Link between geomagnetic reversal paths and secular variation of the field over the past 5 Myr, Nature, 358, 230–233, 1992.

  8. Glatzmaier, G. A. and P. H. Roberts, A three-dimensional self-consistent computer simulation of a geomagnetic field reversal, Nature, 377, 203–209, 1995.

  9. Gubbins, D., Geomagnetic polarity reversals: a connection with secular variation and core-mantle interaction?, Rev. Geophys., 32, 61–83, 1994.

  10. Gubbins, D. and G. Sarson, Geomagnetic field morphologies from a kinematic dynamo model, Nature, 368, 51–55, 1994.

  11. Hartl, P. and L. Tauxe, Precursor to the Matuyama/Brunhes transition-field instability as recorded in pelagic sediments, Earth Planet. Sci. Lett., 138, 121–135, 1996.

  12. Herr, B., M. Fuller, M. Haag, and F. Heider, Influence of drilling on two records of the Matuyama/Brunhes polarity transition in marine sediment cores near Gran Canaria, in Proc. ODP Sci. Results., 157, edited by P. P. E. Weaver, H.-U. Schmincke, J. V. Firth, and W. Duffield, pp. 57–69, Ocean Drilling Program, College Station, 1998.

  13. Hoffman, K. A., Dipolar reversal states of the geomagnetic field and coremantle dynamics, Nature, 359, 789–794, 1992.

  14. Karlin, R., M. Lyle, and G. R. Heath, Authigenic magnetite formation in suboxic marine sediments, Nature, 326, 490–493, 1987.

  15. Kent, D. V. and D. A. Schneider, Correlation of paleointensity variation recorded in the Brunhes/Matuyama polarity transition interval, Earth Planet. Sci. Lett., 129, 135–144, 1995.

  16. Kirschvink, J. L., The least-squares line and plane and the analysis of palaeomagnetic data, Geophys. J. R. astr. Soc., 62, 699–718, 1980.

  17. Laj, C., A. Mazaud, R. Weeks, M. Fuller, and E. Herrero-Bervera, Geomagnetic reversal paths, Nature, 351, 447, 1991.

  18. Langereis, C. G., A. A. M. van Hoof, and P. Rochette, Longitudinal confinement of geomagnetic reversal paths as a possible sedimentary artefact, Nature, 358, 226, 230, 1992.

  19. Love, J. J. and A. Mazaud, A database for the Matuyama-Brunhes magnetic reversal, Phys. Earth Planet. Inter., 103, 207–245, 1997.

  20. Mazaud, A. and J. E. T. Channell. The top Olduvai polarity transition at ODP Site 983 (Iceland Basin), Earth Planet. Sci. Lett., 166, 1–13, 1999.

  21. McFadden, P. L., C. E. Barton, and R. T. Merrill, Do virtual geomagnetic poles follow preferred paths during geomagnetic reversals?, Nature, 361, 342–344, 1993.

  22. Murray, R. W., R. Wigley, and Shipboard Scientific Party, Interstitial water chemistry of deeply buried sediments from the southwest African margin: a preliminary synthesis of results from Leg 175, in Proc. ODP Init. Repts., 175, edited by G. Wefer, W. H. Berger, and C. Richter et al., pp. 547–553, Ocean Drilling Program, College Station, 1998.

  23. Oda, H. and H. Shibuya, Deconvolution of long-core paleomagnetic data of Ocean Drilling Program by Akaike’s Bayesian Information Criterion minimization, J. Geophys. Res., 101, 2815–2834, 1996.

  24. Oda, H. and H. Shibuya, An improvement in ABIC-minimizing deconvolution for continuously measured magnetic remanence data, Earth Planets Space, 50, 15–22, 1998.

  25. Oda, H., H. Shibuya, and V. Hsu, High resolution paleomagnetic records of Brunhes/Matuyama polarity transition from ODP Leg 124 (Celebes and Sulu Seas), Geophys. J. Int., 142, 319–338, 2000.

  26. Prevot, M. and P. Camps, Absence of preferred longitude sectors for poles from volcanic records of geomagnetic reversals, Nature, 366, 53–57, 1993.

  27. Quidelleur, X., J. Holt, and J.-P. Valet, Confounding influence of magnetic fabric on sedimentary records of a field reversal, Nature, 374, 246–249, 1995.

  28. Shipboard Scientific Party, Site 1082, in Proc. ODP Init. Repts., 175, edited by G. Wefer, W. H. Berger, and C. Richter et al., pp. 273–312, Ocean Drilling Program, College Station, 1998.

  29. Tarduno, J. A. and S. L. Wilkison, Non-steady state magnetic mineral reduction, chemical lock-on, and delayed remanence acquisition in pelagic sediments, Earth Planet. Sci. Lett., 144, 315–326, 1996.

  30. Tauxe, L., Sedimentary records of relative paleointensity of the geomagnetic field: Theory and practice, Rev. Geophys., 31, 319–354, 1993.

  31. Tauxe, L., T. Herbert, N. J. Shackleton, and Y. S. Kok, Astronomical calibration of the Matuyama-Brunhes boundary: consequences for magnetic remanence acquisition in marine carbonates and the Asian loess sequence, Earth Planet. Sci. Lett., 140, 133–146, 1996.

  32. Valet, J.-P., P. Tucholka, V. Courtillot, and L. Meynadier, Paleomagnetic constraints on the geometry of the geomagnetic field during reversals, Nature, 356, 400–407, 1992.

  33. Van Hoof, A. A. M. and C. G. Langereis, The upper and lower Thvera sedimentary geomagnetic reversal records from southern Sicily, Earth Planet. Sci. Lett., 114, 59–75, 1992.

  34. Wefer, G., W. H. Berger, and C. Richter, et al., Proceedings of the Ocean Drilling Program, Initial Reports, 175 (Part 1), 577 pp., Ocean Drilling Program, College Station, 1998.

  35. Yamazaki, T., P. A. Solheid, and G. M. Frost, Rock magnetism of sediments in the Angola-Namibia upwelling system with special reference to loss of magnetization after core recovery, Earth Planets Space, 52, 329–336, 2000.

  36. Yukutake, T. and H. Tachinaka, Separation of the Earth’s magnetic field into the drifting and the standing parts, Bull. Earthq. Res. Inst., 47, 65–97, 1969.

Download references

Author information



Corresponding author

Correspondence to Toshitsugu Yamazaki.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Yamazaki, T., Oda, H. A Brunhes-Matuyama polarity transition record from anoxic sediments in the South Atlantic (Ocean Drilling Program Hole 1082C). Earth Planet Sp 53, 817–827 (2001).

Download citation


  • Polarity Transition
  • Natural Remanent Magnetization
  • Anoxic Sediment
  • Anhysteretic Remanent Magnetization
  • Virtual Geomagnetic Pole