Application of Stable Isotope and Hydrogeochemistry to Investigat the Origin and Water Resources' Quality Variations in Zarivar Lake Cathment Area

Document Type : Research Article

Authors

• H. Mohammadzadeh
• S. Ebrahimpoor

10.22067/jsw.v0i0.15321

Abstract

Zarivar Lake, located in west of Marivan -Kurdistan province, is an important natural freshwater body in Iran. Therefore, it is essential to investigate and to protect the water resources of the lake's catchment area. In this research, to develop the Marivan meteoric water line (MMWL - δ18O vs. δ2H), to determine the surface (lake) and groundwater interactions, to investigate the factores effecting on water quality, and to find out the origin of cations and anions, water samples (rain, lake and ground waters) were collected during measurements of fild parameters (TDS, EC, pH and T ). Based on isotope results, the MMWL is obtained as δ2H = 7.5 δ18O + 9.0 and the average δ18O values of rain, groundwater and lake water are -8.3‰, -7.0‰ , and 5.5‰ , respectively, and δ2H values of these waters are -53.6‰, -42.2‰ , and 16.9‰ , respectively. Isotopic results also indicate that the origin of groundwater resources is meteoric water with minor evaporation lost, however, the lake water showes relatively high evaporation lost. The d-excess indicates that the influence of the Mediterranean water masses on this area. Bsed on hydrchemical results it seems that the composition of both groundwater and lake water is attributed to natural rock-dissolution proccesses, with anthropogenic sources (fertelizers, waste water, etc.) for some ions (Cl-, SO42) in the lake water. Mineral saturation indexes indicate the existence of very low amount of evaporative minerals, and low retention time of water within the aquifer. Cluster analysis of water quality parameters and sampling locations shows similarity amoung all groundwater samples taken around the lake. In addition, all lake water samples also have similar quality, except samples taken from North and South of the lake, and groundwater discharges into the lake from the North West area. The results of factor analysis indicate that three factors controlling about 83.3% of total sample variations.

Keywords

• stable isotope
• Saturation Indexes
• Marivan plain
• Cluster analysis

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