Evaluation of transverse fault performance in inter-basin water transport using isotopic and color tracking studies, case study: Dimeh spring, Koohrang

Dimeh Spring emerges from the Zarab Anticline, Zagros Mountains (Iran), and the mean annual discharge is ~2.5 m3/s. However, preliminary evaluations suggest that the spring recharge is from the Zarab Anticline but in several previous dye tracing tests, that the dye was injected in the Zarab anticline, the dye was not seen in the Dimeh karstic Spring. Then, in order to find the catchment area of this spring, the present study has focused on tectonic aspects. For this purpose the tracing techniques were employed to determine the flow path and isotope studies used to determine the catchment elevation. First, the transverse fractures that extended from Zardkooh Mountains to Dimeh Spring area were identified and 30 kg of Uranine dye was injected in one of them, Khadang Valley. Unlike previous tests, the dye was observed in Dimeh Spring. Furthermore, the relationship between elevation and δ18O in precipitation shows that a big part of Dimeh Spring waters recharges in Zardkooh Mountains.