Evaluating the Effect of Geomorphology in Hydrological and Chemical Characteristics of Springs in Kangir Catchment

Kangir catchment with a drainage area of 458 km2, in Ilam province, is part of Folded Zagros structural zone. The aim of this research is to evaluate the hydrological and chemical properties of springs and their relations with geomorphologic landforms of the study area. To achieve the purpose of this study, Karstic landforms, joint system, fold symmetry index (FSI) and fold front sinuosity (FFS), hydrographs and chemical characteristics of springs were measured quantitatively. Evaluating the FSI and FFS indexes represents young folding system of the study area. Result of this study reveals that dominant direction of joints is parallel to anticline hinge, or perpendicular to topographic slope. Evaluating the hydrographs of 6 springs reveals that the rate of recession coefficient (α) in Sarab, Farzegah, Venit, Debiran, Halashi and Majin springs are very low, 0.0058, 0.0074, 0.0098, 0.0055, 0.0078 and 0.0047 respectively. The high amounts of dynamic storage volumes, electrical conductivity, total hardness, and of water compounds like cations and anions in the studied springs imply the low development of karstic voids and high contact area between water and bedrock. On general, young karstification system as well as direction of karstic joints, perpendicular to topographic slope, has resulted in long duration of all spring discharges.