【摘要】 研究稀土元素在流体中的地球化学行为及其控制因素 ,对利用稀土示踪与流体有关的地球化学过程具有重要意义。海底高温流体稀土组成研究表明 ,不同背景、岩性热液系统喷口流体的稀土含量差别较大 ,与海水之间可达几个数量级 ,但配分模式却非常类似 ,即普遍具有 LREE富集、高的正 Eu异常特征。流体的稀土组成与岩石或矿物的蚀变程度、结构构造有关 ,同时受流体的温压、p H值、Eh值、络合介质种类等因素的影响 ,其配分模式是流体循环、迁移过程中络合、吸附、矿物沉淀等不同因素共同作用而再次调整的结果。正 Eu异常作为高温流体的特征标志 ,可以用来示踪与高温流体有关的地球化学作用过程 ,同时 Y/Ho比值、负 Ce异常可以用来示踪与流体 /海水混合有关的化学过程。更多还原

【Abstract】 It is very important to study the behavior and control factors of rare earth elements in fluids for applying them to tracing of the geochemical processes. The REE compositions of the vent fluid show wide contents in concentration but similar on the REE distribution patterns among different seafloor hydrothermal system with various setting and rocks. The distribution patterns common possess high positive Eu anomalies and enriched LREE. The composition of the fluids is related to alteration and texture of rock or mineral and is controlled by environment conditions such as temperature, pressure, pH, Eh, complexing agents. The distribution patterns of high temperature fluids are the results of sorption, complexation, and mineral deposit process and the REE patterns were adjusted and redistributed during fluid circulation and migration. Some REE’s parameters such as Eu, Ce anomalies and Y/Ho ratios can be used to study processes concerning fluid. For example, the positive Eu anomalies, negative Ce anomalies and Y/Ho ratios as mark of involving high temperature fluid and sea water may be used to trace geochemical processes concerning on mixing.更多还原