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南秦岭泥盆纪沉积柱中产有多种类型海底热水沉积岩．它们的ΣＲＥＥ偏低（平均６３．０９×１０－６），ＲＥＥ配分曲线平缓右倾，Ｌａ／Ｙｂ＝２～８，Ｃｅ亏损，总体上与海水相似。产于Ｓｅｄｅｘ含矿层中的热水沉积岩具有正Ｅｕ异常，与现代海底热液及红海热液沉积物可比；而产在Ｓｅｄｅｘ含矿层以下地层中的热水沉积岩Ｅｕ亏损，与ＥＰＲ热液沉积物相似。ＲＥＥ地球化学研究和岩石学研究结果一致，支持热水沉积岩ＲＥＥ来源于海水及部分下伏沉积柱（包括基底），含矿热水沉积岩是盆地热演化到一定阶段具有一定深度和规模的循环对流体系在海底的化学沉积，而Ｓｅｄｅｘ含矿层以下地层中的热水沉积岩则是浅部热水对流循环的海底显示．成岩和变质作用对岩石的ＲＥＥ未造成影响。
There are many types of seafloor hydrothermal sedimentary rocks in the South Qinling Devonian sedimentary column. Their ΣREE is low (average 63.09 × 10-6), REE distribution curve is gentle rightward, La / Yb = 2 ~ 8, Ce is loss, generally similar to seawater. The hydrothermal sedimentary rocks produced in the Sedex ore-bearing layer have positive Eu anomalies comparable to the modern seafloor hydrothermal and Red Sea hydrothermal sediments, while the hydrothermal sedimentary rocks produced in the strata below the Sedex ore-bearing are depleted in abundance and are associated with the EPR hydrothermal sediments similar. The results of REE geochemistry and petrology are in good agreement. The REE supports hydrothermal sedimentary rocks derived from seawater and some underlying sedimentary columns (including basement). The ore-bearing hydrothermal sedimentary rocks are circular convection with a certain depth and scale at a certain stage of thermal evolution of the basin The system is chemically deposited on the seabed, whereas the hydrothermal sedimentary rocks in the formations below the Sedex ore-bearing formation are the seabed displays of shallow hot-water convection cycles. Diagenesis and metamorphism have no effect on the REE of rocks.