Modelo físico-matemático de un evento geomagnético registrado en sedimentos del pleistoceno tardío en la Argentina

Authors

  • A.M. Sinito Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional del Centro
  • A.M. Walther Consejo Nacional de Investigaciones Científicas y Técnicas
  • M.J. Orgeira Consejo Nacional de Investigaciones Científicas y Técnicas
  • C. Conti Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires

Keywords:

geomagnetic field, physico-malhematical model

Abstract

A physico-malhematical model for describing the behaviour of the geomagnetic field during an excursion or reversion of polarity is evaluated. This model uses one main central dipole , whose intensity oscillates sinusoidally, and eight radial oscillating and drifting dipoles located near the core-mantle interface. The analysis is carried out comparing the theoretic results obtained from the model with paleomagnetic data from sediments of the subsoil of the city of Bahia Blanca, Prov. of Buenos Aires and from paleoestuarine sediments outcropping near Gualeguaychú, Prov. of Entre Rios, assigned to the late Pleistocene, in which a magnetic event was recorded.
After fitting some parameters of the model, a good correlation between the theoretic and paleomagnetic profiles of Declination and Inclination is obtained. The conclusions confirm that the record of Gualeguaychú y Bahia Blanca belong to the same magnetic event.

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References

Alldredge, L.R.y Hurwitz, R., 1964. Radial dipoles as the sources of the Earth's main magnetic field. Joum. of Geophys. Res., 69, 12, 2631-2639.

Balbetti, M. y McElhinny, M., 1972. Evidence of a geomagnetic excursion 30000 yr BP. Nature, 239, 5371, 327-330.

Bochev, AZ., 1975. Presenting the Earth's magnetic field as a field of six optimal dipoles. C.R. Acad. Bulgar Sci., 28, 569- 571.

Coe, R.S., 1977. Source models to account for Lake Mungo paleomagnetic excursion. Nature, 269, 49-51.

Creer, K.M. y Tucholka, P., 1983. Epilogue. Geomagnetism of baked clays and sediments. Creer, K.M., Tucholka, P. y Barton, C.E. (eds.). Elsevier, Amsterdam.

Chaar, E. y Farinati, E., 1988. Evidencias paleontológicas y sedimentológicas de un nivel marino pleistocènico en Bahia Bianca, Provincia de Buenos Aires, Argentina. II Jom. Geol. Bon., Actas, 47-54.

Gonzalez, M., 1984. Depósitos marinos del Pleistoceno superior en Bahia Bianca, Pcia. de Buenos Aires. IX Cong. Geol. Arg., Actas, 3, 538-555.

Guida, N.G. y Gonzalez, M.A, 1984. Evidencias paleoestuáricas en el sudeste de Entre Ríos, su evolución con niveles marinos relativamente elevados del Pleistoceno superior y Holoceno. IX Cong. Geol. Arg., Actas, III, 557.

Hogg, T.E., 1978. The holocene geomagnetic field in Europe. Ph. D. Dissertation, University of Edinburgh.

Laj, C., Weeks, R. y Fuller, M., 1989. Observations and models of reversals transition fields. Geomagnetism and Paleomagnetism. Lowes et al (ed.). Kluwer Academic Publisher, 185-203.

Liddicoat, J.C., 1979. Monolake geomagnetic excursion. Joum. of Geophys. Res., 84, Bl, 261.

Orgeira, M.J., Beraza, L., Vizán, H., Bobbio, M.L. y Vilas, J.F., 1990. Evidence for a geomagnetic field excursion in the Late Pleistocene (Entre Ríos, Argentina). Quatem. of South America a. Antarctic Penin., 6, 173-188.

Peddie, N., 1979. Current loop models of the Earth's magnetic field. Joum. of Geophys. Res., 84, B9, 4517.

Peirce, J.W. y Clarck, M.J., 1978. Evidence from Iceland on Geomagnetic reversal during the Wiscosian Ice Age. Nature, 273, 456-458.

Sinito, AM., 1988. Análisis de las variaciones geomagnéticas paleoseculares recientes en el Hemisferio Sur y su relación con los modelos físicos que postulan el origen del campo magnético terrestre. Tesis. Universidad de Buenos Aires.

Sinito, AM., 1990. Models of geomagnetic secular variations on recent times for South America. Phys, of the Earth a. Planet Int, 64, 2, 133-142.

Sinito, AM. y Orgeira, MJ., 1990. Análisis del comportamiento del campo geomagnètico durante una excursión. Geoacta, 17, 2, 115-124.

Trie, E., Laj, C., Jéhanno, C., Valet, J.P., Kissel, C., Mazaud, A, Iaccarino, S., 1991. High resolution record of the Upper Olduvai transition from Po Valley (Italy) sediments: support for dipolar transition geometry?. Phys, of the Earth a. Planet Int, 65, 319-336.

Trie, E., Laj, C., Valet, J.P., Tucholka, P., Paterne, M., Guichard, F., 1991. The Blake geomagnetic event: transition geometry, dynamical characteristics and geomagnetic significance. Earth a. Planet Sci. Lett, 102, 1-13.

Walther, AM., Orgeira, M.J., Sinito, AM. y Conti, C., 1992. Nuevas evidencias de un evento del campo magnètico terrestre registrado en sedimentos pleistocenos tardíos en Argentina. Rev. Asoc. Geol. Arg., en prensa.

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Published

1993-12-12

How to Cite

Sinito, A., Walther, A., Orgeira, M., & Conti, C. (1993). Modelo físico-matemático de un evento geomagnético registrado en sedimentos del pleistoceno tardío en la Argentina. Geoacta, 20, 37–46. Retrieved from https://revistas.unlp.edu.ar/geoacta/article/view/13701

Issue

Vol. 20 (1993)

Section

Scientific work

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