摘要
通过对未蚀变流纹岩、蚀变流纹岩和金矿石中稀土元素组成及分布模式的研究，表明岩浆热液与以大气降水为来源的地下水相混合后所形成的成矿热液中稀土元素具有富集ＬＲＥ、稀土元素总量低以及Ｅｕ具有明显负异常的特征。蚀变流纹岩中出现Ｅｕ负异常的原因是由于次生矿物对ＲＥ３＋有容纳作用，而对于Ｅｕ２＋没有明显的容纳作用，从而导致Ｅｕ２＋被迁移所致。稀土元素可能以（ＲＥ（ＣＯ３）３Ｆ）４－，（ＲＥ（ＣＯ３）Ｆ２）－，（ＲＥ（Ｆ，Ｃｌ）２）＋形式存在于热液中进行迁移。ＨＲＥ络合物与ＬＲＥ络合物稳定性不同是导致稀土元素发生分馏的直接原因。
The study of rare earth element(REE)pattern in rhyolites of the Erdaogou gold deposit located in western Liaoning Province indicates that the REE pattern in unaltred rhyolite is characterized by typical enrichment in LRE and minor negative Eu anomaly. But altered rhyolites are characterized by distinet Eu negative anomaly, except Eu, the other REE is similar to that in unaltered rhyolite.The reason of formation of sharp negative Eu anomaly in altered rhyolite is that secondary minerals are able to accommodate RE3+ and not to accommodate Eu2+ during alteration process. The REE pattern in fluid formed by mixing of magmatic water with meteoric water is characterized by low REE contents, enrichment in LRE and sharp negative Eu anomaly.
出处
《中国稀土学报》
CAS
CSCD
北大核心
1996年第2期97-102,共6页
Journal of the Chinese Society of Rare Earths
关键词
地球化学
流纹岩
金矿床
稀土元素
矿化
Rare earths, Geochemistry, Rhyolite, Erdaogou glod deposit
