Twenty new intensity determinations of the ancient geomagnetic field have been obtained from groups of potsherds and brick fragments from Syria. These artifacts, archeologically well dated from ∼6000 B.C. to approximately A.D. 1200, have been analyzed using the Thellier and Thellier [1959] method as modified by Coe [1967]. Intensity values have been corrected for the effects of anisotropy of thermal remanent magnetization and cooling rate. Our results indicate that field intensities were moderate in Syria from ∼6000 B.C. to ∼3500 B.C., with values of ∼30–40 μT. There was a significant increase in intensity by a factor of 2 from ∼3500 B.C. to ∼700 B.C., which was interrupted by a moderate decrease between ∼2550 B.C. and ∼1750 B.C. During more recent periods, our results show an intensity minimum approximately A.D. 200 and a maximum around the tenth century. Comparison with different data sets from the eastern Mediterranean and central Asia shows that geomagnetic field intensity variations were consistent at this large regional scale, at least over the last 5 millennia.

An archeointensity study was carried out on 14 sites of Syrian baked clay artifacts, archeologically dated between ∼2500 BC and ∼1600 BC. Using an experimental protocol involving high‐temperature magnetization measurements, well‐defined mean intensity values were derived for 13 different sites with three to nine results obtained at the fragment level per site. Results of similar ages are coherent and the new data set is in good agreement with previous archeointensity results obtained from the same region. All together these data allow one to refine the evolution of the geomagnetic field intensity in the Middle East during the third and the second millennium BC. In particular, they show the occurrence of three periods of rather sharp intensity increase at ∼2600 BC, ∼2200 BC and ∼1600 BC possibly at the times of climatic cooling in the eastern North Atlantic, further suggesting a connection between the Earth's magnetic field and multi‐decadal climatic events.

Jean-Claude MARGUERON 2 «… Nous apprenons à séparer et non pas à voir ce qui relie. Pour résoudre un problème selon Descartes, il faut séparer en autant de petites parties qu'on le peut et les résoudre les unes après les autres. Mais ce n'est valable que quand il y a addition de problèmes. Dès qu'il y a un tout, on ne peut le comprendre en additionnant ce qu'on sait des parties séparées. De par son organisation et son fonctionnement, un tout est plus que la somme de ses parties. Ainsi, notre mode de pensée formé dès le primaire, consolidé dans le secondaire et aggravé irrémédiablement à l'Université, nous amène à être lucides pour séparer, mais myopes pour relier… » 3 Edgar MORIN Résumé-Le principal objectif de cette NAAO est de mettre en évidence que l'application stricte des règles de la stratigraphie archéologique 4 , sans induire d'erreurs évidentes au premier degré, peut modifier la réalité ancienne au point de donner naissance à une situation qui n'a jamais existé 5. L'analyse s'appuie sur un réexamen de la stratigraphie de Khafajé.

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