La crise d'aridité climatique de la fin du 3ème millénaire av. J.-C., à la lumière des contextes géomorphologique de 3 sites d'Iran Oriental (Bam, Tepe Damghani, Jiroft)

The climatic aridity in the late third millennium is a fact attested by the paleo-climate reconstructions for the Near and Middle East as well in Central Asia. The question is what are the consequences of climate aridity for human societies and how they have adapted. The geomorphological study of Sabzevar in northeastern Iranian Plateau, Bam and Jiroft in southeastern of the same Plateau, shows that between the Chalcolithic and Iron Age water resources diminish but,thanks to favourable trapping groundwater tectonic settings, human societies adapt to changing location and adopting new irrigation techniques, in this case the qanats.