Investigation on the Potential of OSL for Dating Qanat in the Dasht-e Bayaz Region of Northeastern Iran Using the SAR Protocol for Quartz

Document Type : Seismology and Engineering Seismology


1 Oxford University Center for the Environment

2 Institute of Geophysics, University of Tehran

3 University of Oxford

4 Geological Survey of Iran, Tehran

5 University of Cambridge

6 Birjand University


In some parts of Iran, such as Dasht-e-Bayaz, the line of wells of the Qanat systems have been displaced by coseismic faulting. If we can date the age of these Qanat wells and measure the amount of offset, we will be able to estimate the slip-rate of the fault. The existing constraints on age of ancient Qanats in Iran are typically assigned from archaeological investigations of nearby habitation sites. We present for the first time the results of OSL dating from spoil deposits associated with the Dasht-e-Bayaz Qanat. We further explore the possibility of dating Qanat directly using the novel method of OSL. The minimum ages which are assigned to maintenance and construction of Dasht-e-Bayaz Qanat, using SAR protocol are 15.8±1.6ka and 22.1±2.7ka, respectively. Archeological investigations suggest that the Qanat ages are much younger than ages obtained by OSL. We present evidence that the SAR approach that we have chosen is operative but not relevant. The OSL method has provided ages that are consistent with stratigraphic layers in the well, but these layers were not fully bleached during construction. The single aliquot method to which dim samples we've applied in the recent research is not an efficacious way to achieve the age of Qanats and may need to test for more samples.