Revival of Qanats by Using Geoelectrical Methods: A Case Study of Gastaj, Eastern Iran

The Geoelectrical method plays a critical role in exploration and reviving Qanats. DC resistivity method is a subtype of Geoelectrical method that has been used to explore and revive Qanats. Gaftaj is located about 25 kilometres north-west of Ferdows city, South Khorasan province, Iran. In this area, there are four main Qanats. In the paper, resistivity data have been surveyed by Schlumberger array and 36 electrical soundings was performed on two profiles. The apparent resistivity contour map was prepareded for tow profiles and near sonding. The results showed that excavation is not appropriate for revival of Qanats. Moreover, the result showed that gallery is the best option for revival of Qanats. The apparent resistivity contour map cleared a fault between Shale of the Mesozoic priod and Conglomerate of the Cenozoic priod in this region. Finally, drilling of wells was recommended on the fault for providing water in this region.