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Early cretaceous absolute geomagnetic paleointensities from Córdoba Province (Argentina)

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Abstract

We present here new paleointensity and geochronology results from Early Cretaceous volcanic rocks of Sierra Chica de Cordoba (Argentina). The new K-Ar isotopic ages of 5 samples range from 136 to 122 Ma. Twenty five samples from 7 individual flows yielded acceptable paleointensity estimates. The mean paleointensity values per flow are ranging from 53.0 ± 1.9 to 25.4 ± 2.6 μT and the corresponding Virtual Dipole Moments (VDMs) are ranging from 9.3±1.3 to 4.6±0.5 (1022 Am2). This corresponds to the mean value of 7.3±1.7×1022 Am2, which is compatible to the present geomagnetic axial dipole. Currently available selected paleointensity data from 80 to 130 Ma suggest that geomagnetic field strength frequently fluctuated before and during the Cretaceous Normal Superchron while the magnetic polarity maintained stable. The mean paleointensities derived from Córdoba lavas agree remarkably well with those obtained from the Paraná Magmatic Province (133–132 Ma). This reinforces the hypothesis about the unreliability of ‘Mesozoic Dipole Low’. Key words: Paleointensity, rock-magnetism, Early Cretaceous, South America.

References

  1. Barton, C. E., R. Baldwin, D. Barraclough, S. Bushati, M. Chiappini, Y. Cohen, R. Coleman, G. Hulot, V. Kotze, V. Golovkov, A. Jackson, R. Langel, F. Lowes, D. McKnight, S. Macsmillan, L. Newitt, N. Peddie, J. Quinn, and T. Sabaka, International geomagnetic reference field, 1995 revision, Geophys. J. Int., 125, 318–321, 1996.

  2. Buddington, A. F. and D. H. Linsley, Iron-titanium oxides minerals and synthetic equivalents, J. Petrol., 5, 310–357, 1964.

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

  4. Coe, R., S. Grommé, and E. A. Mankinen, Geomagnetic paleointensities from radiocarbon-dated lava flows on Hawaii and the question of the Pacific nondipole low, J. Geophys. Res., 83, 1740–1756, 1978.

  5. Cottrell, R. D. and J. A. Tarduno, Geomagnetic paleointensity derived from single plagioclase crystals, Earth Planet. Sci. Lett., 169(1–2), 1999.

  6. 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., 105, 23579–23584, 2000.

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

  8. Dunlop, D. and Ö. Özdemir, Rock-Magnetism, Fundamentals and Frontiers, Cambrige University Press, 573 pp., 1997.

  9. Dunlop, D. and Ö. Özdemir, Theory and application of the Day Plot, Theoretical curves and tests using titanomagnetite data, J. Geophys. Res., 107, doi: 1029/2001JB000486, 2002.

  10. Geuna, S. E. and H. Vizán, New Early Cretaceous palaeomagnetic pole from Córdoba Province (Argentina): revision of previous studies and implications for the South American database, Geophys. J. Int., 135, 1085–1100, 1998.

  11. Goguitchaichvili, A. and M. Prévot, Magnetism of oriented single crystals of hemo-ilmenite showing self-reversal of thermoremanent magnetization, J. Geophys. Res., 105, 2761–2781, 2000.

  12. Goguitchaichvili, A., M. Prévot, J. Thompson, and N. Roberts, An attempt to determine the absolute geomagnetic field intensity in Southwestern Iceland during the Gauss-Matuyama reversal, Phys. Earth Planet. Int., 115, 53–66, 1999.

  13. Goguitchaichvili, A., L. Alva-Valdivia, J. Urrutia-Fucugauchi, J. Morales, and O. Ferreira-Lopes, On the Reliability of Mesozoic Dipole Low: New Absolute Paleointensity Results from Parana Flood Basalts (Brazil), Geophys. Res. Lett., 29(13), 1655, 10.1029/2002GL015242, 2002.

  14. Gordillo, C. E. and A. Lencinas, Geología y petrología del extremo norte de la Sierra de Los Cóndores, Córdoba, Bol. Academia Nacional de Ciencias, Córdoba, 46, 73–108, 1967.

  15. Haggerty, S. E., Oxidation of opaque mineral oxides in basalts, in Oxides Minerals, edited by D. Rumble, Mineral. Soc. Amer., Reviews in Mineralogy, vol. 3, 300 pp., 1976.

  16. Haggerty, S. E., Oxide textures—A mini atlas, Rev. Mineral., 25, 12–219, 1991.

  17. Hulot, G. and Y. Gallet, Do superchrons occur without any paleomagnetic warning?, Earth Planet. Sci. Lett., 210, 191–201, 2003.

  18. Kosterov, A. and M. Prévot, Possible mechanism causing failure of Thellier paleointensity experiments in some basalts, Geophys. J. Int., 134, 554–572, 1998.

  19. Larson, R. L. and P. Olson, Mantle plumes control magnetic reversal frequency, Earth Planet. Sci. Lett., 107, 437–447, 1991.

  20. República Argentina, 1957–1987, Publicaciones especiales de la Asoc. Geol. Argentina, Ser. B, Didáctica y Complementaria, 19, 628 pp. Buenos Aires., 1990.

  21. McFadden, R. T. and R. T. Merrill, Fundamental transitions in the geodynamo as suggested by paleomagnetic data, Phys. Earth Planet. Int., 91, 253–260, 1995.

  22. McFadden, R. T. and R. T. Merrill, Evolution of geomagnetic reversal rate since 160 Ma: Is the process continuous?, J. Geophys. Res., 105, 28445–28460, 2000.

  23. Pan, Y., M. Hill, R. Zhu, and J. Shaw, Further evidence for low intensity of the geomagnetic field during the early Cretaceous time: using the modified Shaw and microwave technique, Geophys. J. Int., 157, 553–564, 2004.

  24. Prévot, M., R. S. Mainkinen, S. Grommé, and A. Lecaille, High paleointensity of the geomagnetic field from thermomagnetic studies on rift valley pillow basalts from the middle Atlantic ridge, J. Geophys. Res., 88, 2316–2326, 1983.

  25. Prévot, M., E. A. Mankinen, R. S. Coe, and S. Grommé, The Steens Mountain (Oregon) geomagnetic polarity transition 2. Field intensity variations and discussion of reversal models, J. Geophys. Res., 90, 10417–10448, 1985.

  26. Prévot, M., M. E. Derder, M. McWilliams, and J. Thompson, Intensity of the Earth’s magnetic field: evidence for a Mesozoic dipole low, Earth Planet. Sci. Lett., 97, 129–139, 1990.

  27. Riisager, P., J. Riisager, X. Zhao, and R. S. Coe, Cretaceous geomagnetic paleointensities: Thellier experiments on Pillow lavas and submarine basaltic glass from the Ontong Java Plateau, Geochem. Geoph. Geosys., 4/18, doi: 10.1029/2003GC000611, 2004.

  28. Smirnov, A. V. and J. A. Tarduno, Thermochemical remanent magnetization in Precambrian rocks: Are we sure the geomagnetic field was weak?, J. Geophys. Res., 110, B06103, 2005.

  29. Solé, J. and P. Enrique, X-ray fluorescence analysis for the determination Analytica Chimica Acta, 440, 199–205, 2001.

  30. Steiger, R. H. and E. Jäger, Subcomission on geochronology: Convention on the use of decay constants in geo- and cosmochronology, Earth Planet. Sci. Lett., 36, 359–362, 1977.

  31. Tanaka, H. and M. Kono, Paleointensities from a Cretaceous basalt platform in Inner Mongolia, northeastern China, Phys. Earth Planet. Int., 133, 147–157, 2002.

  32. Tarduno, J. A., R. D. Cottrell, and A. V. Smirnov, High geomagnetic intensity during the Mid-Cretaceous from Thellier analyses of single plagioclase crystals, Science, 291, 1779–1783, 2001.

  33. Tarduno, J. A., R. D. Cottrell, and A. V. Smirnov, The Cretaceous superchron geodynamo: observations near the tangent cylinder, PNAS, 99, 14020–14025, 2002.

  34. Tauxe, L. and H. Staudigel, Strength of the geomagnetic field in the Cretaceous Normal Superchron: New data fron submarine basaltic glass of the Trodoos Ophiolite, Geochem. Geoph. Geosys., 5/22, doi:10.1029/ 2003GC000635, 2004.

  35. Tauxe, L., T. A. T. Mullender, and T. Pick, Pot-bellies, wasp-waists and superparamagnetism in magnetic hysteresis, J. Geophys. Res., 95, 12337–12350, 1996.

  36. Tauxe, L., Bertram, H. Neal, and Ch. Severino, Physical intrepretation of hysteresis loops: Micromagnetic modeling of fine particle magnetite, Geochem. Geophys. Geosyst., 3(10), 1055, doi:10.1029/ 2001GC000241, 2002.

  37. Thellier, E. and O. Thellier, Recherches géomagnetiques sur les coulees volcaniques d’Auverne, Ann. Geophys., 1, 37–52, 1944.

  38. Thellier, E. and O. Thellier, Sur l’sintensité du champ magnétique terrestre dans le passé historique et géologique, Ann. Géophysique, 15, 285–376, 1959.

  39. Zhao, X., P. Riisager, J. Riisager, U. Draeger, R. S. Coe, and Z. Zheng, New Palaeointensity results from Cretaceous basalt of Inner Mongolia, China, Phys. Earth Planet. Int., 141, 131–140, 2004.

  40. Zhu, R., K. Hoffman, Y. Pan, R. Shi, and L. Daming, Evidence for weak geomagnetic intensity prior to the Cretaceous normal subchron, Phys. Earth Planet. Int., 136, 187–199, 2003.

  41. Zhu, R., L. Ching-Hua, R. Shi, G. Shi, Y. Pan, and J. Shao, Paleointensities determined from the middle Cretaceous basalt in Liaoning Province, northeastern China, Phys. Earth Planet. Int., 142, 49–59, 2004a.

  42. Zhu, R., L. Ching-Hua, R. Shi, G. Shi, Y. Pan, G. Shi, and J. Shao, Is there a precursor to the Cretaceous normal subchron? New paleointensity and age determination from Liaoning province, northeastern China, Phys. Earth Planet. Int., 147, 117–126, 2004b.

  43. Zhu, R., K. Hoffman, S. Nomade, P. Renne, R. Shi, G. Shi, Y. Pan, and G. Shi, Geomagnetic paleointensity and direct age determination of the ISEA (M0r?) chron, Earth Planet. Sci. Lett., 217, 285–295, 2004c.

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Correspondence to Avto Goguitchaichvili.

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Key words

  • Paleointensity
  • rock-magnetism
  • Early Cretaceous
  • South America