中文摘要：

本文从苏锡常地区浅层地下水含水介质及包气带沉积环境的角度．阐明了浅层地下水中Cl^-和Na^＋浓度东高西低的分布特征。根据数据分析，浅层地下水中Na^＋与Cl^-的毫克当量比值rNa／rCl与海侵形成的沉积环境和沉积历史关系密切。地下水淡化历史越长，含水层介质中吸附的Na^＋与地下水中的Ca^2＋和Mg^2＋之间的阳离子交换吸附程度越高，大量的Na^＋进入地下水中，使得rNa/rCl比值越高。

英文摘要：

Based on the sedimentary environment of the shallow groundwater aquifer and its vadose zone, the paper illustrates the decreasing trend of sodium and chloride ion concentrations from east to west in shallow groundwater in the Suzhou-Wuxi-Changzhou region. According to a data analysis, the ratio of rNa/rCl in shallow groundwater is closely related to the sedimentary environment of transgression and sedimentary history. The longer the freshening history of groundwater is, the higher the degrees of the cation and exchange adsorption between sodium ions adsorbed in aquifer media and calcium and magnesium ions in groundwater will be. As large numbers of sodium ions enter groundwater, the ratio of rNa/rCl is higher and higher.