- Open Access
Improvement of the secular variation curve of the geomagnetic field in Egypt during the last 6000 years
Earth, Planets and Space volume 51, pages1325–1329(1999)
A total of 115 ceramic specimens out of 41 samples from 9 archeological sites in Giza, Fayoum, Benisuef, El Minia, Malawy, and Sohag were collected. They represent 14 well-determined ages covering the last 6000 years. Rock magnetic properties such as Curie temperature and hysteresis loops have been measured for these samples to identify the magnetic carrier; it is found to be fine-grained magnetite. All specimens were investigated using the classic Thellier double heating technique (Thellier and Thellier, 1959) and the modification after Odah et al. (1995) to obtain the paleointensity data. These paleointensities and the previous results of Odah et al. (1995) were used to improve the secular variation curve of the geomagnetic field in Egypt for the last 6000 years. This curve shows a maximum of 72.8 µT at about 250 AD and a minimum of 33 µT at about 3500 BC. It also shows a general decrease of the magnetic moment during the last 2000 years.
Aitken, M. J., A. L. Allsop, G. D. Bussell, and M. B. Winter, Geomagnetic intensity in Egypt and Western Asia during the second millennium BC, Nature, 310, 305–306, 1984.
Athavale, R. N., Intensity of the geomagnetic field in prehistoric Egypt, Earth Planet. Sci. Lett., 6, 221–224, 1969.
Boak, A. E. R., The temples, coin hoards, botanical and zoological reports, seasons 1924–1931, Univ. Michigan Press, 1933.
Bresciani, E., Messione die scavo medint Madi, Rapporto preliminiare della campagne di scavo 1966 e 1967, 1968.
Creer, K. M., P. Tucholka, and C. E. Barton, Geomagnetism of Baked Clays and Recent Sediments, 324 pp., Elsevier, Amsterdam, 1983.
Games, K. P., The magnitude of the archeomagnetic field in Egypt between 3000 and 0 BC, Geophys. J. R. astr. Soc., 63, 45–56, 1980.
Hussain, A. G., Archeological investigation in Egypt: Inclination and field intensity determination, J. Geophys., 53, 131–140, 1983.
Hussain, A. G., The secular variation of the geomagnetic field in Egypt in the last 5000 years, Pageoph, 125, 67–90, 1987.
O’Connor, D., Report on Abydos: The Early Dynastic Project, pp. 1–5, New York University, 1997.
Odah, H., Archeomagnetic studies in some localities in A. R. Egypt, Ph.D. Thesis, Fac. of Sci. Mansoura University, 182 pp., Egypt, 1993.
Odah, H., F. Heider, A. G. Hussain, V. Hoffmann, H. Soffel, and M. ElGamili, Paleointensity of the geomagnetic field in Egypt from 4000 BC to 150 AD using the Thellier method, J. Geomag. Geoelectr., 47, 41–58, 1995.
Rogers, J., J. M. W. Fox, and M. J. Aitken, Magnetic anisotropy in ancient pottery, Nature, 227, 644–655, 1979.
Thellier, E., Early research on the intensity of the ancient geomagnetic field, Phys. Earth Planet. Inter., 13, 241–244, 1977.
Thellier, E. and O. Thellier, Sur l’intensité du champ magnétique terrestre, en France, a l’epoque gallo-romaine, Compt. Rend., 222, 905–907, 1959.
Walton D., Alteration and its effects on the reproducibility of archaeomagnitudes from Tel-El-Amarana, J. Geomag. Geoelectr., 38, 1349–1352, 1986.
About this article
Cite this article
Odah, H. Improvement of the secular variation curve of the geomagnetic field in Egypt during the last 6000 years. Earth Planet Sp 51, 1325–1329 (1999). https://doi.org/10.1186/BF03351606
- Secular Variation
- Thermomagnetic Curve
- Archeological Ceramic