作　　者： ; ; ; ; ;

机构地区： 中国地质大学资源学院

出　　处： 《吉林大学学报（地球科学版）》 2003年第4期437-442,共6页

摘　　要： 对东沟坝矿床矿石及赋矿火山岩的稀土组成研究表明:矿石普遍发育显著的Eu正异常和弱的Ce负异常,说明成矿热液为温度较高(250℃以上)、相对还原的热流体。Eu正异常和弱Ce负异常同时在矿石中发育,说明矿石沉淀时较高温度的热流体与少量的海水发生了对流混合。除Eu、Ce之外矿石稀土配分模式总体与赋矿的火山岩接近,说明成矿金属主要来自豆坝群火山岩。根据矿石中大量发育重晶石和矿石普遍具有的LREE富集、明显的Eu正异常和弱Ce负异常的事实,推断成矿流体中SO2-4的大量出现与岩浆脱气组分贡献有关。 REE geochemistry method has been used to trace the resources of the oreforming materials in the Donggouba polymetallic deposit. The REE contents of the ores and its host rocks were analyzed respectively and the ores have apparent positive Eu and weak Ce negative anomalies in the chondrite- normalized REE distribution patterns of the ores, indicating the oreforming hydrothermal fluids had a high temperature (greater than 250℃) and were relatively reductive. The coexistence of both apparent positive Eu anomalies and weak negative Ce anomalies in the ores indicate the convectively mixing of hydrothermal fluids with a small amount of seawater when the ores were precipitated on ancient seafloor. The REE distribution patterns of ores are similar to those of the host rocks on the whole except for Eu and Ce, which implicates the oreforming metallic elements came mainly from the volcanic rocks of the Douba Group. The presence of large amount of barite, the enriched LREE and apparent positive Eu anomaly and weak negative Ce anomaly suggests that the SO2-4 were a dominant anion in the oreforming fluid and was related to a degassing processes of magmatic components.

关 键 词： 多金属矿床 成矿物质 稀土元素 元素地球化学 矿质来源

领　　域： [天文地球] [天文地球] [天文地球] [天文地球]