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对扬子地块北缘贵池地层区从震旦系到三叠系沉积地层各种岩石的稀土元素组成研究表明，全剖面稀土平均含量（１２７μｇ／ｇ）低于沉积岩的平均含量（２３０μｇ），但与地台区（１２９μｇ／ｇ）十分接近。按岩类平均，页岩稀土含量最高（２３０μｇ／ｇ），砂岩及粉砂岩次之（２１３μｇ／ｇ），灰岩最低（１８μｎ／ｇ）。不同时代地层稀土含量受岩性控制，以碳酸盐岩为主的奥陶系（４０μｇ／ｇ）、三叠系地层（４４μｇ／ｇ）稀土含量最低，以陆源碎屑岩为主的志留系（２３１μｇ／ｇ）、泥盆系地层（２４８μｇ／ｇ）最高。不同岩性、不同时代的地层，尽管稀土含量有别，但稀土分布模式却很相似，构成一组右倾斜负铕异常的平行曲线，在∑（Ｌａ～Ｎｄ）－∑（Ｓｍ～Ｈｏ）－∑（Ｅｒ～Ｌｕ）三角图解上，各样品点很集中，反映本区稀土组成的均一性。相似的稀土组成表明，本区自震旦纪到三叠纪长期处于稳定的构造环境，具地台区的属性。沉积环境与世界典型地台区类似。江南古陆不是本区沉积物的来源区．可能来自北方古陆。
The REE composition of various rocks from the Sinian to the Triassic sedimentary formations in the Guichi reservoir area on the northern margin of the Yangtze block shows that the average REE content (127 μg / g) in the whole section is lower than that of sedimentary rocks (230 μg) But very close to the platform area (129μg / g). According to the average rock type, the content of rare earth in shale is the highest (230μg / g), followed by sandstone and siltstone (213μg / g), and the lowest is limestone (18μn / g). In different ages, the rare earth content in the strata is controlled by lithology. The Ordovician (40 μg / g) mainly composed of carbonate rocks has the lowest REE content in the Triassic strata (44 μg / g) (231μg / g), Devonian strata (248μg / g) were the highest. In different lithology and strata of different ages, the distribution patterns of rare earths are similar to each other, forming a set of parallel curves of right-inclined negative Eu anomaly in Σ (La ~ Nd) -Σ (Sm ~ Ho) - Σ (Er ~ Lu) triangle diagram, the sample points are concentrated, reflecting the homogeneity of the composition of rare earth in the region. The similar composition of rare earths shows that this area has been in a stable tectonic environment since Sinian to Triassic for a long time and has the properties of platform area. Sedimentary environment and the typical Taiwan area similar. Jiangnan ancient land is not the source area of sediments. May come from the northern ancient land.