In order to explore the hydrogeological supply order and conceptual hydrogeological model of the Gasikule Salt Lake, PHREEQC software is used to calculate the existence forms of chemical compositions and saturation indexes of various waters from Gasikule salt lake located in the western margin of Qinghai province. The results reveal that Na, K, Ca, Mg, C(4), Cl and S(6) are mainly in the forms of free ions Na⁺, K⁺, Ca²⁺, Mg²⁺, HCO₃^-, Cl^- and HCO₄^2-, while only small amounts of Mg, C(4) and S(6) form complexes with other ions. The conceptual hydrogeological model is shown as follows. Firstly, most of the stream water formed by precipitation and snow melt supplies the mudstone layer and forms the confined water. Secondly, most of the confined water supplies pore water and eventually enters lake water. Thirdly, the lake water is transfered to surface brine and intercrystalline brine after strong evaporation and concentration effect due to cold and dry climate. Fourthly, the deep CaCl₂ type brine continuously supplies the surface brine area and intercrystalline brine area by the buried faults existing at the east surface brine area and the Karst channel existing at the salina, respectively. Fifthly, the surface brine and intercrystalline brine exchange deeply. This study may provide some basic information for the hydrogeological evolution of the salt lake in the Qinghai-Tibet Plateau.

chemical composition  /  existence form  /  saturation index  /  conceptual hydrogeological model  /  Gasikule salt lake