Water Resources and Power

Considering the characteristics of SO₄^2- concentration and sulfur isotope in the Ku-Xin-Sha area of Xinjiang, groundwater chemistry and SO₄^2- zone characteristics and sources were analyzed. And then the circulation process of groundwater in this area was judged. The results show that the study area is mainly divided into 4 types of water chemistry, and the evolution direction of the water chemistry type is HCO₃·Cl·SO₄^2--Na·Mg·Ca→SO₄^2-·Cl-Na→Cl·SO₄^2--Na·Mg→Cl-Na. The ion concentration of different geomorphological units has a gradually increasing trend. The concentration of SO₄^2- has obvious regional differentiation, which is low in the north and high in the south, and low in the middle and high in the east and west. The SO₄^2- concentration and δ³⁴S value of the water body gradually increased from the upstream replenishment area to the downstream drainage area, indicating that the potential sources of δ³⁴S in different geomorphic units have shifted or changed. The source of groundwater SO₄^2- is generally represented by atmospheric precipitation, the leaching of terrestrial evaporative salt and evaporative rocks in the transitional phase between land and sea, and the influence of irrigation water. Therefore, the study was divided into four watersheds to be studied separately, and the sulfur value and sulfate changes in each watershed were analyzed.