Skip to main content


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

A relative paleointensity record of the geomagnetic field since 1.6 Ma from the North Pacific


A paleomagnetic study was conducted on a sediment core KR0310-PC1 taken from the central North Pacific in order to obtain a relative paleointensity record in the Matuyama chron from this region. The core reached to about 1.6 Ma. The age control is based on the correlation of the S ratio (S−0.1T) variations with a global oxygen-isotope stack. Isothermal remanent magnetization (IRM) was used as the normalizer of the relative paleointensity estimation; anhysteretic remanent magnetization (ARM) was not adopted because ARM is sensitive to magnetostatic interaction among magnetic particles, which is evidenced in these sediments by an inverse correlation between the ratio of ARM to saturation IRM (SIRM) and SIRM without significant magnetic grain-size changes. For the last 350 kyrs, the record of core NGC65, which was obtained at practically the same site as KR0310-PC1 and covers the Brunhes chron (Yamazaki, 1999), was incorporated because the upper part of KR0310-PC1 was physically disturbed. In the record of NGC65/KR0310-PC1, the average paleointensity in the late Matuyama chron is not lower than that during the Brunhes chron, which does not support the conclusion of Valet et al. (2005) based on their Sint-2000 stack. A spectral analysis on the NGC65/KR0310-PC1 paleointensity record shows a power at the 100 kyr eccentricity period. The relative paleointensity and magnetic properties of NGC65/KR0310-PC1 were compared with those of MD982185 from the western equatorial Pacific (Yamazaki and Oda, 2002, 2005). The two sites belong to different oceanographic regimes. Coherent variations in the relative paleointensity despite incoherent changes in the magnetic properties suggest that rock-magnetic contamination to the relative paleointensity is small, if any, and the 100 kyr period in the relative paleointensity records would reflect the geomagnetic field behavior.


  1. Banerjee, S. K., J. King, and J. A. Marvin, Rapid method for magnetic granulometry with applications to environmental studies, Geophys. Res. Lett., 8, 333–336, 1981.

  2. 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.

  3. Cande, S. C. and D. V. Kent, Revised calibration of the geomagnetic polarity timescale for the Late Cretaceous and Cenozoic, J. Geophys. Res., 100, 6093–6095, 1995.

  4. Carcaillet, J. T., N. Thouveny, and D. L. Bourles, Geomagnetic moment instability between 0.6 and 1.3 Ma from cosmonuclide evidence, Geophys. Res. Lett., 30, doi: 10.1029/2003GL107750, 2003.

  5. Channell, J. E. T. and H. F. Kleiven, Geomagnetic palaeointensities and astrochronological ages for the Matuyama-Brunhes boundary and the boundaries of the Jaramillo Subchron: palaeomagnetic and oxygen isotope records from ODP Site 983, Phil. Trans. Roy. Soc. Lond. Ser. A, 358, 1027–1047, 2000.

  6. Channell, J. E. T., D. A. Hodell, J. McManus, and B. Lehman, Orbital modulation of the Earth’s magnetic field intensity, Nature, 394, 464–468, 1998.

  7. Channell, J. E. T., A. Mazaud, P. Sullivan, S. Turner, and M. E. Raymo, Geomagnetic excursions and paleointensities in the Matuyama Chron at Ocean Drilling Program Sites 983 and 984 (Iceland Basin), J. Geophys. Res., 107, doi: 10.1029/2001JB000491, 2002.

  8. Channell, J. E. T., J. H. Curtis, and B. P. Flower, The Matuyama-Brunhes boundary interval (500–900 ka) in North Atlantic drift sediments, Geophys. J. Int., 158, 489–505, 2004.

  9. Day, R., M. Fuller, and V. A. Schmidt, Hysteresis properties of titanomagnetites: grain-size and compositional dependence, Phys. Earth Planet. Inter., 13, 260–267, 1977.

  10. Evans, M. E. and F. Heller, Environmental Magnetism, 293 pp, Academic Press, 2003.

  11. Fuller, M., Geomagnetic field intensity, excursions, reversals and the 41,000-yr obliquity signal, Earth Planet. Sci. Lett., 245, 605–615, 2006.

  12. Gogorza, C. S. G., J. M. Lirio, H. Nuñez, M. Chaparro, H. R. Bertorello, and A. M. Sinito, Paleointensity studies on Holocene-Pleistocene sediments from Lake Escondido, Argentina, Phys. Earth Planet. Inter., 145, 219–238, 2004.

  13. Guyodo, Y. and J.-P. Valet, Global changes in intensity of the Earth’s magnetic field during the past 800 kyr, Nature, 399, 249–252, 1999.

  14. Guyodo, Y., P. Gaillot, and J. E. T. Channell, Wavelet analysis of relative geomagnetic paleointensity at ODP Site 983, Earth Planet. Sci. Lett., 184, 109–123, 2000.

  15. Guyodo, Y., G. D. Acton, S. Brachfeld, and J. E. T. Channell, A sedimentary paleomagnetic record of the Matuyama chron from the Western Antarctic margin (ODP Site 1101), Earth Planet. Sci. Lett., 191, 61–74, 2001.

  16. Horng, C.-S., M.-Y. Lee, H. Pälike, K.-Y. Wei, W.-T. Liang, Y. Iizuka, and M. Torii, Astronomically calibrated ages for geomagnetic reversals within the Matuyama chron, Earth Planets Space, 54, 679–690, 2002.

  17. Horng, C.-S., A. P. Roberts, and W.-T. Liang, A 2.14-Myr astronomically tuned record of relative geomagnetic paleointensity from the western Philippine Sea, J. Geophys. Res., 108, doi:10.1029/2001JB001698, 2003.

  18. Kent, D. V. and N. D. Opdyke, Paleomagnetic field intensity variation recorded in a Brunhes epoch deep-sea sediment core, Nature, 266, 156–159, 1977.

  19. King, J. W., S. K. Banerjee, and J. Marvin, A new rock-magnetic approach to selecting sediments for geomagnetic paleointensity studies: application to paleointensity for the last 4000 years, J. Geophys. Res., 88, 5911–5921, 1983.

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

  21. Kok, Y. S. and L. Tauxe, A relative geomagnetic paleointensity stack from Ontong-Java Plateau sediments for the Matuyama, J. Geophys. Res., 104, 25401–25413, 1999.

  22. Laj, C., C. Kissel, A. Mazaud, J. E. T. Channell, and J. Beer, North Atlantic palaeointensity stack since 75 ka (NAPIS-75) and the duration of the Laschamp event, Phil. Trans. R. Soc. Lond. A, 358, 1009–1024, 2000.

  23. Lehman B., C. Laj, C. Kissel, A. Mazaud, M. Paterne, and L. Labeyrie, Relative changes of the geomagnetic field intensity during the last 280 kyear from piston cores in the Açores area, Phys. Earth Planet. Inter., 93, 269–284, 1996.

  24. Levi, S. and S. K. Banerjee, On the possibility of obtaining relative paleointensities from lake sediments, Earth Planet. Sci. Lett., 29, 219–226, 1976.

  25. Lisiecki, L. E. and M. E. Raymo, A Pliocene-Pleistocene stack of 57 globally distributed benthic δ18O records, Paleoceanography, 20, doi: 10.1029/2004PA001071, 2005.

  26. McFadden, P. L. and A. Reid, Analysis of paleomagnetic inclination data, Geophys. J. R. astr. Soc., 69, 307–319, 1982.

  27. Meynadier, L., J.-P. Valet, F. C. Bassinot, N. J. Shackleton, and Y. Guyodo, Asymmetric saw-tooth pattern of the geomagnetic field intensity from equatorial sediments in the Pacific and the Indian Oceans, Earth Planet. Sci. Lett., 126, 109–127, 1994.

  28. Moskowitz, B. M., Theoretical grain size limits for single-domain, pseudo-single-domain and multi-domain behavior in titanomagnetite (x = 0.6) as a function of low-temperature oxidation, Earth Planet. Sci. Lett., 47, 285–293, 1980.

  29. Paillard, D., L. Labeyrie, and P. Yiou, Macintosh program performs time-series analysis, EOS trans., 77, 379, 1996.

  30. Rampino, M. R., Possible relationship between changes in global ice volume, geomagnetic excursions, and eccentricity of the Earth’s orbit, Geology, 7, 584–587, 1979.

  31. Roberts A. P., B. Lehman, R. J. Weeks, K. L. Verosub, and C. Laj, Relative paleointensity of the geomagnetic field over the last 200,000 years from ODP Sites 883 and 884, North Pacific Ocean, Earth Planet. Sci. Lett., 152, 11–23, 1997.

  32. Sato, T., H. Kikuchi, M. Nakashizuka, and M. Okada, Quaternary geomagnetic field intensity: constant periodicity or variable period?, Geophys. Res. Lett., 25, 109–127, 1998.

  33. Schwartz, M., S. P. Lund, and T. C. Johnson, Geomagnetic field intensity from 71 to 12 ka as recorded in deep-sea sediments of the Blake Outer Ridge, North Atlantic Ocean, J. Geophys. Res., 103, 30407–30416, 1998.

  34. Skinner, L. C. and I. N. McCave, Analysis and modelling of gravity- and piston coring based on soil mechanics, Mar. Geol., 199, 181–204, 2003.

  35. St-Onge, G., J. S. Stoner, and C. Hillaire-Marcel, Holocene paleomagnetic records from the St. Lawrence Estuary, eastern Canada: centennial- to millennial-scale geomagnetic modulation of cosmogenic isotopes, Earth Planet. Sci. Lett., 209, 113–130, 2003.

  36. Sugiura, N., ARM, TRM and magnetic interactions: Concentration dependence, Earth Planet. Sci. Lett., 42, 451–455, 1979.

  37. Széréméta, N., F. Bassinot, Y. Balut, L. Labeyrie, and M. Pagel, Oversampling of sedimentary series collected by giant piston coere: Evidence and correlations based on 3.5-kHz chirp profiles, Paleoceanography, 19, doi:10.1029/2002PA000795, 2004.

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

  39. Tauxe, L. and N. J. Shackleton, Relative paleointensity records from the Ontong-Java Plateau, Geophys. J. Int., 117, 769–782, 1994.

  40. Tauxe, L. and G. Wu, Normalized remanence in sediments of the western equatorial Pacific: relative paleointensity of the geomagnetic field?, J. Geophys. Res., 95, 12337–12350, 1990.

  41. Tauxe, L., J. L. Steindorf, and A. Harris, Depositional remanent magnetization: Toward an improved theoretical and experimental foundation, Earth Planet. Sci. Lett., 244, 519–529, 2006.

  42. Thouveny, N., J. Carcaillet, E. Mareno, G. Leduc, and D. Nérini, Geomagnetic moment variation and paleomagnetic excursions since 400 kyr BP: a stacked record from sedimentary sequences of the Portuguese margin, Earth Planet. Sci. Lett., 219, 377–396, 2004.

  43. Valet, J.-P. and L. Meynadier, Geomagnetic field intensity and reversals during the past four million years, Nature, 366, 234–238, 1993.

  44. Valet J.-P., L. Meynadier, and Y. Guyodo, Geomagnetic dipole strength and reversal rate over the past two million years, Nature, 435, 802–805, 2005.

  45. Williams, T., N. Thouveny, and K. M. Creer, A normalised intensity record from Lac du Bouchet: geomagnetic palaeointensity for the last 300 kyr?, Earth Planet. Sci. Lett., 156, 33–46, 1998.

  46. Wollin, G., D. B. Ericson, and W. B. F. Ryan, Variations in magnetic intensity and climatic change, Nature, 232, 549–551, 1971.

  47. Yamamoto, Y., T. Yamazaki, T. Kanamatsu, N. Ioka, and T. Mishima, Relative paleointensity stack during the last 250 kyr in the Northwest Pacific, J. Geophys. Res., 112, doi:10.1029/2006JB004477, 2007.

  48. Yamazaki, T., Relative paleointensity of the geomagnetic field during Brunhes Chron recorded in North Pacific deep-sea sediment cores: orbital influence?, Earth Planet. Sci. Lett., 169, 23–35, 1999.

  49. Yamazaki, T. and N. Ioka, Long-term secular variation of the geomagnetic field during the last 200 kyr recorded in sediment cores from the western equatorial Pacific, Earth Planet. Sci. Lett., 128, 527–544, 1994.

  50. Yamazaki, T. and N. Ioka, Cautionary note on magnetic grain-size estimation using the ratio of ARM to magnetic susceptibility, Geophys. Res. Lett., 24, 751–754, 1997a.

  51. Yamazaki. T. and N. Ioka, Environmental rock-magnetism of pelagic clay: implications for Asian eolian input to the North Pacific since the Pliocene, Paleoceanography, 12, 111–124, 1997b.

  52. Yamazaki, T. and H. Oda, Orbital influence on Earth’s magnetic field: 100,000-year periodicity in inclination, Science, 295, 2435–2438, 2002.

  53. Yamazaki, T. and H. Oda, Intensity-inclination correlation on long-term secular variation of the geomagnetic field and its relevance to persistent non-dipole component, AGU Monograph 145 “Timescales of the Paleomagnetic Field”, 287–298, 2004.

  54. Yamazaki, T. and H. Oda, A geomagnetic paleointensity stack between 0.8 and 3.0 Ma from equatorial Pacific sediment cores, Geochem. Geophys. Geosyst., 6, doi: 10.1029/2005GC001001, 2005.

  55. Yokoyama, Y. and T. Yamazaki, Geomagnetic paleointensity variation with a 100 kyr quasi-period, Earth Planet. Sci. Lett., 181, 7–14, 2000.

Download references

Author information



Corresponding author

Correspondence to Toshitsugu Yamazaki.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Yamazaki, T., Kanamatsu, T. A relative paleointensity record of the geomagnetic field since 1.6 Ma from the North Pacific. Earth Planet Sp 59, 785–794 (2007).

Download citation

Key words

  • Paleomagnetism
  • paleointensity
  • North Pacific
  • orbital modulation
  • normalizer
  • magnetostatic interaction