The Gas Hure Salt Lake (GHSL) in the northwestern Qaidam Basin,western China,is rich in boron (B) resources,but its B-resource origin is hardly known.Hydrochemical compositions and B isotope characteristics of different waters were collected around the GHSL,including the river water,stream water,spring water,salt-lake brine, intercrystalline brine,well water,drilling brine,and solar pond brine.The hydrochemical signatures suggest that silicates,carbonates and evaporates are the main B-bearing rocks during the water dynamic.The reservoir estimation of B resources shows that the Kulamulekesay River (KLMR) and the Atekan River (ATKR) contribute annually 18.3 tons and 22.84 tons of B,respectively,with a total amount of 11.72 × 104 tons of B during the past 5.7 ka.In comparison with the known B reservoir (32.96 × 104 tons) in the GHSL,a significant amount of B in the GHSL was probably recharged from deep fluids and sediments around the GHSL.The B concentration and B-enrichment degree are shaped by the evaporation process,which are highly elevated at the carnallite and bischofite stages.