OSL dating of the Miam Qanat (KĀRIZ) system in NE Iran

• The potential of OSL to obtain the time of construction and maintenance of Qanats is shown.
• This method can also be used for dating wells and handmade ditches and canals.
• Dating of Qanats (KĀRIZ) is important for finding the place of origin of Qanats.
• Relates knowledge between settlements, landscape evolution, and palaeoclimate.
• OSL dating of the Miam Qanat suggests it is the oldest known.

This article presents the first direct absolute dating method of a Qanat system obtained through optically stimulated luminescence (OSL) dating of grains in spoil heaps, using feldspar single-grain, feldspar multi-grain and quartz multi-grain samples. This novel and highly promising approach to improving our understanding of the chronology of Qanats is more important than the final age results.Hitherto, dating of Qanats has been based on indirect evidence from historical reports or archaeological investigations of nearby settlements. This study demonstrate the ability of OSL to date this type of subterranean irrigation feature, which is important in the study of both the archaeology of human settlement and palaeoenvironmental change in arid regions. This method can also be used for dating wells and handmade ditches and canals.Our results show that advanced irrigation technologies existed at Miam in what is now north-east Iran much earlier than previously thought. Dating the now disused Qanat at 3.6–4.3 ka makes it the oldest known. Single-grain dating of sand-sized feldspar that overlie construction spoil show that the Miam Qanat was maintained until at least 1.6 ka. The early development of Qanat irrigation indicates that the causes of widespread societal collapse in eastern Iran in the Bronze Age might not have been driven purely by climatic pressures.