中文摘要：

稀土元素（REE）作为示踪元素在各种岩石的成因、物源、演化及形成环境等方面均具有重要意义。对镇江大港下蜀黄土-古土壤剖面中稀土元素含量和分布特征的研究结果表明：镇江下蜀黄土-古土壤剖面∑REE变化于193．7～214．9μgg^-1之间，平均值为207．7μgg^-1下蜀黄土REE绝对丰度明显高于黄土高原黄土，这主要是由于下蜀黄土中粘粒组分含量较高，对REE特别是轻稀土元素（LREE）产生较强的吸附作用造成的。镇江下蜀黄土和黄土高原黄土的REE特征参数及配分模式具有很好的相似性，它们均与上陆壳（UCC）具有相近的REE组成；下蜀黄土剖面不同时代样品的REE分布模式几乎完全一致。这些特征为下蜀黄土的“风成说”提供了新的地球化学证据，并揭示了下蜀黄土的物质来源区可能是一个广泛而开放的空间范围，下蜀黄土粉尘颗粒在搬运过程中经过了高度的混合。镇江下蜀黄土的稀土元素特征主要继承了原始物质的特征，粉尘物质堆积后虽经过较强的风化成土作用，轻重稀土间的分馏强于黄土高原黄土，但总体来说化学风化对REE的分馏作用并不十分显著，古土壤层与黄土层样品的REE组成差异不大，没有产生明显的Ce和Eu再分馏。

英文摘要：

Variation of Xiashu Loess-Paleosol of Zhenjiang in rare earth element （REE） composition was studied, and the findings show that ∑REE varied in the range from 193.7 to 214.9 μg g^-1 with an average value of 207.7 μg g^-1. Compared with the Loess of the Loess Plateau, Xiashu Loess were significantly higher in REE absolute abundance, because of its higher content of clay that adsorbed REEs （especially LREEs）. But they showed similar REE distribution patterns and characteristic parameters, and they were also quite similar to the upper continent crust （UCC） in REE composition. The REE distribution patterns of Xiashu Loess samples of different ages were almost identical, which displays uniformity of Xiashu Loess in material composition of the profile. The above-mentioned features provide new geochemical evidence of the aeolian origin theory for Xiashu Loess, and indicate that the materials of Xiashu Loess might come from an open and broad area and get highly mixed as aeolian dust during the process of transportation. The REE characteristics of Xiashu Loess are inherited mainly from its source materials. Even though the aeolian dusts has undergone stronger weathering and soil-forming process after they were settled and accumulated, the fractionation between LREE and HREE in Xiashu Loess is more apparent than in the loess of the Loess Plateau. On the whole, chemical weathering does not show any remarkable influence on REE fractionation, and the Paleosol does not vary much from the loess in REE composition or show any apparent Ce-depletion and Eu-depletion.