The Relationship of the Hot and Mineral Springs in Munzur and Pülümür Valleys (Tunceli) with the Tectonic Structures of the Region and their Hydrogeochemical Properties

The N-S flowing Munzur and Pülümür Rivers, which have the largest drainage areas in Tunceli Province, merge in the city center, and continue as a single river towards the south. In the southern area, there are smaller drainage areas such as Dinar and Rabat. In this study, the hydrogeochemical properties of the hot and mineral springs located in the mentioned drainage areas and the relationship of these springs with the faults in the region were investigated. The most important structural element controlling the reaching of hot and mineral springs to the surface is the primary and secondary deformation structures of the right lateral strike-slip Nazımiye Fault Zone. PermoCarboniferous aged impermeable schists form the basement rocks in the area hydrogeologically. Permian aged marble and crystallized limestones are the reservoir rocks of the hot and mineral waters which are outcropped in the drainage areas of Munzur and Pülümür Rivers. The presence of Eocene-Miocene aged semi-permeable flysch and permeable limestones cover rocks in this recharge area of the reservoir rocks indicates that the system is open. The pH and electrical conductivity of the hot and mineral waters in the system change between 5.96-6.80 and 2231-2930 μS/cm, respectively. Temperature of these waters varies between 35 to 20°C when they reach up to the surface. The total amount of dissolved solids ranges from 1300 to 1600 mg /L. The most abundant cation present in the waters is Ca+2; the most abundant anion is HCO3-. The Na-K-Mg geothermometer results of the hot and mineral waters correspond to the immature waters where the water-rock relationship is not an equilibrium. The pH and electrical conductivity of the cold waters are between 6.66 to 7.28 and 471 to 891 μS/cm, respectively. All waters examined here are of the Ca-Mg HCO3 type