中文摘要：

结合稳定同位素（D1、8O1、3C）,应用聚类分析和因子分析两种多元统计分析方法,对鄂尔多斯沙漠高原白垩系含水层地下水水化学演化特征进行研究。结果表明：研究区环河组和洛河组地下水均可分为3大类,且大致在地下水补给区、径流区和排泄区分别聚类,每一类的水化学特征和同位素特征均存在一定的差异;研究区地下水均起源于大气降水,发生了岩盐溶滤、碳酸盐矿物溶解、硫酸盐矿物溶解、硅酸盐矿物溶解和阳离子交换等水文地球化学作用。相对洛河组地下水,环河组地下水水化学演化特征还受到了大气降水稀释作用和酸碱演化的影响。

英文摘要：

Combined with stable isotopes（D,18O,13C）,two kinds of multivariate statistical analysis methods（cluster analysis and factor analysis） were used to study the hydrogeochemical evolution characteristics of the groundwater Cretaceous aquifer in Ordos desert plateau.The results indicated that the groundwater of Huan river and Luo river in studied area can be divided into three categories,and generally clustered in recharge,runoff and discharge areas of groundwater.The hydrogeochemical and isotopic characteristics of each type were different.The origin of groundwater in studied area was the precipitation,which experienced salt leaching,carbonate mineral dissolution,sulfate mineral dissolution,silicate mineral dissolution,cation exchange and other hydrogeochemical processes.Compared with Luo river groundwater,the hydrogeochemical evolution of Huan river groundwater was also influenced by precipitation dilution and pH evolution.