Skip to main content

Advertisement

The intensity of the geomagnetic field in the late-Archaean: new measurements and an analysis of the updated IAGA palaeointensity database

Article metrics

Abstract

We firstly present the results of a detailed palaeointensity study performed on 54 samples from 9 volcanic units of late Archaean age (2724-2772 Ma) from the Pilbara Craton, Western Australia. These results were severely affected by magnetomineralogical alteration occurring during the laboratory heating process necessitating the application of a correction procedure. The correction allowed results from three lavas to pass strict selection criteria but we deem that only one of these exhibits sufficient internal consistency to be considered moderately reliable. It yields a virtual dipole moment of 47±6 ZAm2which is 60% of the present-day value. We combine this determination with a filtered dataset from the updated IAGA (International Association of Geomagnetism and Aeronomy) palaeointensity database, PINT08. Directional secular variation has recently been shown to have changed fundamentally since the Archaean, probably as a consequence of inner core growth since that time. However, here we argue that it is still unclear whether this evolution was accompanied by a single long timescale change in average poloidal field intensity. While the distribution of Precambrian palaeointensity determinations as a whole is significantly lower than that for the last 300 Myr, we show that this finding largely reflects data from the Proterozoic aeon. The distribution of more ancient measurements from the late Archaean-earliest Proterozoic is indistinguishable from that of the last 300 Myr which might suggest that a ‘Proterozoic dipole low’ period existed between two periods of higher field intensity. Were this pattern of long-term geomagnetic intensity variation to be supported by the addition of new data in the future, then it could indicate a related three-stage evolution in core dynamics, namely: vigorous thermal convection caused by high core-mantle heat flux early in the Earth’s history, weaker thermal convection later as the heat flux fell, and finally, strong compositional convection since the inner core nucleated.

References

  1. Biggin, A. J. and D. N. Thomas, Analysis of long-term variations in the geomagnetic poloidal field intensity and evaluation of their relationship with global geodynamics, Geophys. J. Int., 152(2), 392–415, 2003a.

  2. Biggin, A. J. and D. N. Thomas, The application of acceptance criteria to results of Thellier palaeointensity experiments performed on samples with pseudo-single-domain-like characteristics, Phys. Earth Planet. Inter., 138(3–4), 279–287, 2003b.

  3. Biggin, A. J., H. N. Bőhnel, and F. R. Zuniga, How many paleointensity determinations are required from a single lava flow to constitute a reliable average?, Geophys. Res. Lett., 30(11), 10.1029/2003GL017146, 2003.

  4. Biggin, A. J., M. Perrin, and M. J. Dekkers, A reliable palaeointensity determinations obtained from a non-ideal recorder, Earth Planet. Sci. Lett., 257, 545–563, 2007.

  5. Biggin, A. J., G. Strik, and C. G. Langereis, Evidence for a very long term trend in geomagnetic secular variation, Nature Geosci., 1(6), 395–398, 2008.

  6. Blake, T. S., Late Archean Crustal Extension, Sedimentary Basin Formation, Flood-Basalt Volcanism and Continental Rifting—the Nullagine and Mount Jope Supersequences, Western-Australia, Precambrian Res., 60(1–4), 185–241, 1993.

  7. Blake, T. S., Cyclic continental mafic tuff and flood basalt volcanism in the Late Archaean Nullagine and Mount Jope—Supersequences in the eastern Pilbara, Western Australia, Precambrian Res., 107(3–4), 139–177, 2001.

  8. Blake, T. S., A new regional stratigraphic framework for the lower succession of the Hammersley Province on the northern Pilbara Craton, Western Australia, (in prep.).

  9. Blake, T. S., R. Buick, S. J. A. Brown, and M. E. Barley, Geochronology of a Late Archaean flood basalt province in the Pilbara Craton, Australia: constraints on basin evolution, volcanic and sedimentary accumulation, and continental drift rates, Precambrian Res., 133(3–4), 143–173, 2004.

  10. Buffett, B. A., The thermal state of Earth’s core, Science, 299(5613), 1675–1677, 2003.

  11. Coe, R. S. and G. A. Glatzmaier, Symmetry and stability of the geomagnetic field, Geophys. Res. Lett., 33(21), 2006GL027903, 2006.

  12. Coe, R. S., C. S. Grommé, and E. A. Mankinen, Geomagnetic paleointensities from radiocarbon dated lava flows on Hawaii and the question of the Pacific non-dipole low, J. Geophys. Res. (Solid Earth), 83, 1740–1756, 1978.

  13. Cottrell, R. D. and J. A. Tarduno, In search of high-fidelity geomagnetic paleointensities: A comparison of single plagioclase crystal and whole rock Thellier-Thellier analyses, J. Geophys. Res. (Solid Earth), 105(B10), 23579–23594, 2000.

  14. Courtillot, V. and P. Olson, Mantle plumes link magnetic superchrons to Phanerozoic mass depletion events, Earth Planet. Sci. Lett., 260, 495–504, 2007.

  15. Draeger, U., M. Prevot, T. Poidras, and J. Riisager, Single-domain chemical, thermochemical and thermal remanences in a basaltic rock, Geophys. J. Int., 166(1), 12–32, 2006.

  16. Dunlop, D. J. and Y. Yu, Intensity and polarity of the geomagnetic field during Precambrian time, in Timescales of the Internal Geomagnetic Field, edited by J. E. T. Channell, 85–100, Geophysical monograph series. AGU, Washington DC, 2004.

  17. Granot, R., L. Tauxe, J. S. Gee, and H. Ron, A view into the Cretaceous geomagnetic field from analysis of gabbros and submarine glasses, Earth Planet. Sci. Lett., 256(1–2), 1–11, 2007.

  18. Gubbins, D., D. Alfe, G. Masters, G. D. Price, and M. J. Gillan, Can the Earth’s dynamo run on heat alone?, Geophys. J. Int., 155(2), 609–622, 2003.

  19. Halls, H. C, N. J. McArdle, M. N. Gratton, M. J. Hill, and J. Shaw, Microwave paleointensities from dyke chilled margins: a way to obtain long-term variations in geodynamo intensity for the last three billion years, Phys. Earth Planet. Inter., 147(2–3), 183–195, 2004.

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

  21. Labrosse, S., Thermal and magnetic evolution of the Earth’s core, Phys. Earth Planet. Inter, 140(1–3), 127–143, 2003.

  22. Labrosse, S., J. P. Poirier, and J. L. Le Mouel, The age of the inner core, Earth Planet. Sci. Lett., 190(3–4), 111–123, 2001.

  23. Lay, T., J. Hernlund, E. J. Garnero, and M. S. Thorne, A post-perovskite lens and D heat flux beneath the central Pacific, Science, 314(5803), 1272–1276, 2006.

  24. Leonhardt, R., C. Heunemann, and D. Krasa, Analyzing absolute paleoin-tensity determinations: Acceptance criteria and the software Thellier-Tool4.0, Geochem. Geophys. Geosyst., 5, doi:10.1029/2004GC000807, 2004.

  25. Macouin, M. et al., Low paleointensities recorded in 1 to 2.4 Ga Proterozoic dykes, Superior Province, Canada, Earth Planet. Sci. Lett., 213(1–2), 79–95, 2003.

  26. Macouin, M., J. P. Valet, and J. Besse, Long-term evolution of the geomagnetic dipole moment, Phys. Earth Planet. Inter, 147(2–3), 239–246, 2004.

  27. McClelland, E. and J. C. Briden, An improved methodology for Thellier-type paleointensity determination in igneous rocks and its usefulness for verifying primary thermoremanence, J. Geophys. Res. (Solid Earth), 101(B10), 21995–22013, 1996.

  28. Mullender, T. A. T., A. J. Vanvelzen, and M. J. Dekkers, Continuous Drift Correction and Separate Identification of Ferrimagnetic and Paramagnetic Contributions in Thermomagnetic Runs, Geophys. J. Int., 114(3), 663–672, 1993.

  29. Nagata, T., Y Arai, and K. Momose, Secular variation of the geomagnetic total force during the last 5000 years, J. Geophys. Res., 68, 5277–5282, 1963.

  30. Perrin, M. and V. Shcherbakov, Paleointensity of the earth’s magnetic field for the past 400 Ma: Evidence for a dipole structure during the Mesozoic Low, J. Geomag. Geoelectr., 49(4), 601–614, 1997.

  31. Perrin, M. and E. Schnepp, IAGA paleointensity database: distribution and quality of the data set, Phys. Earth Planet. Inter., 147(2–3), 255–267, 2004.

  32. Prévot, M. and M. Perrin, Intensity of the Earths Magnetic-Field since Precambrian from Thellier-Type Paleointensity Data and Inferences on the Thermal History of the Core, Geophys. J. Int., 108(2), 613–620, 1992.

  33. Riisager, P. and J. Riisager, Detecting multidomain magnetic grains in Thellier palaeointensity experiments, Phys. Earth Planet. Inter., 125(1–4), 111–117, 2001.

  34. Roberts, N. and J. D. A. Piper, A description of the behaviour of the Earth’s magnetic field, in Geomagetism, edited by J. A. Jacobs, pp. 163–260, Elsevier, New York, 1989.

  35. Roberts, P. H. and G. A. Glatzmaier, The geodynamo, past, present and future, Geophys. Astrophys. Fluid Dynamics, 94(1–2), 47–84, 2001.

  36. Selkin, P. A. and L. Tauxe, Long-term variations in palaeointensity, Philos. Trans. R. Soc. London Ser. Math. Phys. Eng. Sci., 358(1768), 1065–1088, 2000.

  37. Selkin, P. A., J. S. Gee, L. Tauxe, W. P. Meurer, and A. J. Newell, The effect of remanence anisotropy on paleointensity estimates: a case study from the Archean Stillwater Complex, Earth Planet. Sci. Lett., 183(3–4), 403–416, 2000.

  38. Smirnov, A. V. and J. A. Tarduno, Secular variation of the Late Archean Early Proterozoic geodynamo, Geophys. Res. Lett., 31(16), 10. 1029/2004GL020333, 2004.

  39. Smirnov, A. V. and J. A. Tarduno, Thermochemical remanent magnetization in Precambrian rocks: Are we sure the geomagnetic field was weak?, J. Geophys. Res. (Solid Earth), 110(B6), 2005.

  40. Smirnov, A. V., J. A. Tarduno, and B. N. Pisakin, Paleointensity of the early geodynamo (2.45 Ga) as recorded in Karelia: A single-crystal approach, Geol., 31(5), 415–418, 2003.

  41. Smith, R. E., J. L. Perdrix, and T. C. Parks, Burial metamorphism in the Hamersley Basin, Western Australia, J. Petrol., 23, 75–102, 1982.

  42. Strik, G., M. J. de Wit, and C. G. Langereis, Palaeomagnetism of the Neoarchaean Pongola and Ventersdorp Supergroups and an appraisal of the 3.0-1.9 Ga apparent polar wander path of the Kaapvaal Craton, Southern Africa, Precambrian Res., 153(1–2), 96–115, 2007.

  43. Strik, G. H. M. A., Palaeomagnetism of late Archaean flood basalt terrains: implications for early Earth geodynamics and geomagnetism, Geolog. Ultraiectina, 242, Utrecht, 160 pp., 2004.

  44. Strik, G. H. M. A., T. S. Blake, T. E. Zegers, S. H. White, and C. G. Langereis, Palaeomagnetism of flood basalts in the Pilbara Craton, Western Australia: Late Archaean continental drift and the oldest known reversal of the geomagnetic field, J. Geophys. Res. (Solid Earth), 108(B12), EPM 2-1-EPM 2-21, 2003.

  45. Tanaka, H. and M. Kono, Paleointensity database provides new resource, Eos Trans. AGU, 75, 498, 1994.

  46. Tarduno, J. A., R. D. Cottrell, and A. V. Smirnov, The Cretaceous super-chron geodynamo: Observations near the tangent cylinder, Proc. Natl. Acad. Sci. USA, 99(22), 14020–14025, 2002.

  47. Tarduno, J. A., R. D. Cottrell, M. K. Watkeys, and D. Bauch, Geomagnetic field strength 3.2 billion years ago recorded by single silicate crystals, Nature, 446, 657–660, 2007.

  48. Tauxe, L. and H. Staudigel, Strength of the geomagnetic field in the Cretaceous Normal Superchron: New data from submarine basaltic glass of the Troodos Ophiolite, Geochem. Geophys. Geosyst., 5, Q02H06, 2004.

  49. Tauxe, L. and T. Yamazaki, Paleointensities, in Geomagnetism, Treatise on Geophysics, edited by M. Kono, pp. 510–563, Elsevier, Amsterdam, 2007.

  50. Thellier, E., Sur l’aimantation des terres cuites et ses applications géophysique, Ann. Inst. Phys. Globe Univ. Paris, 16, 157–302, 1938.

  51. Thellier, E. and O. Thellier, Sur l’intensité du champ magnétique terrestre dans la passé historique et géologique, Ann. Géophys., 15, 285–376, 1959.

  52. Valet, J. P. et al., Absolute paleointensity and magnetomineralogical changes, J. Geophys. Res. (Solid Earth), 101(B11), 25029–25044, 1996.

  53. van der Hilst, R. D. et al., Seismostratigraphy and thermal structure of Earth’s core-mantle boundary region, Science, 315(5820), 1813–1817, 2007.

  54. Wingate, M. T. D., Ion microprobe baddeleyite and zircon ages for Late Archaean mafic dykes of the Pilbara Craton, Western Australia, Aust. J. Earth Sci., 46(4), 493–500, 1999.

  55. Yamamoto, Y., Possible TCRM acquisition of the Kilauea 1960 lava, Hawaii: failure of the Thellier paleointensity determination inferred from equilibrium temperature of the Fe-Ti oxide, Earth Planets Space, 58(8), 1033–1044, 2006.

  56. Yoshihara, A. and Y. Hamano, Intensity of the Earth’s magnetic field in late Archean obtained from diabase dikes of the Slave Province, Canada, Phys. Earth Planet. Inter., 117(1–4), 295–307, 2000.

  57. Zijderveld, J. D. A., Demagnetization in rocks: Analysis of results, in Methods in Palaeomagnetism, edited by S. K. Runcorn, pp. 254–286, Elsevier, New York, 1967.

Download references

Author information

Correspondence to Andrew J. Biggin.

Rights and permissions

Reprints and Permissions

About this article

Key words

  • Palaeointensity
  • Archaean
  • Pilbara
  • magnetomineralogical alteration
  • inner core growth.