摘要
白云鄂博矿床是全球最大的稀土-铌-铁矿床。本文对白云鄂博矿床主矿、东矿赋矿白云岩、不同类型稀土-铌-铁矿石和富钾板岩进行详细的野外地质调查和地球化学成分分析,揭示了成矿元素稀土、铌和主要蚀变元素钠、钾、氟、磷的空间分布规律。结果表明,白云鄂博主采坑比东采坑具有更高的稀土含量,矿体由外围向中心、由浅部向深部有明显的稀土元素(尤其是中-重稀土元素)富集的现象,矿体深部具有更大的中-重稀土元素找矿潜力;成矿元素铌的异常范围与重稀土的异常范围相吻合,表明二者具有密切的共生关系;蚀变元素氟的异常范围与稀土-铌-铁矿体的分布范围相一致,是重要的沉淀成矿元素;蚀变元素磷的异常要明显超过稀土-铌-铁矿体的分布范围,是重要的迁移载体元素;钠化蚀变主要出现在矿体下盘含稀土白云岩中,代表早期高温蚀变过程;钾化蚀变主要发育在矿体上盘的富钾板岩中,代表晚期低温蚀变过程;钾化、萤石化及磷的异常是碳酸岩型稀土矿床最主要的浅部和外围示矿指标。
The Bayan Obo deposit is the world's largest REE-Nb-Fe deposit and holds a pivotal strategic position in China.In this paper,detailed field geological survey and geochemical composition analysis of the REE bearing dolomite,different types of REE-Nb-Fe ore and K-rich slate in the Main Orebody and East Orebody of the Bayan Obo deposit reveal the spatial distribution of the ore-forming elements REE,Nb and the main alteration elements Na,K,F,P.The results show that the Main Orebody has a higher REE content than the East Orebody.The ore bodies have a significant enrichment of REE(especially MREE and HREE)from the periphery to the center and from the shallow to the deep,and the deep part of the ore bodies have a greater exploration potential for MREE and HREE.The anomalous range of the ore-forming element Nb is consistent with that of the HREE,indicating a close symbiotic relationship between them.The anomalous range of the altered element F is consistent with the distribution range of REE-Nb-Fe ore bodies,and is an important precipitation ore-forming element.The anomaly of the alteration element P significantly exceeds the distribution range of REE-Nb-Fe ore bodies and is an important migration carrier element.Sodium alteration mainly occurs in REE bearing dolomite in the foot wall of the ore body,representing the early high-temperature alteration process.Potassium alteration is mainly developed in the K-rich slate on the hanging wall of the ore body,representing the late low-temperature alteration process.Potassium alteration,fluoritization,and phosphorus anomalies are the main shallow and peripheral indicators of carbonatite type REE deposits.
作者
杨奎锋
范宏瑞
邱正杰
李晓春
佘海东
刘双良
李洪涛
张立锋
YANG KuiFeng;FAN HongRui;QIU ZhengJie;LI XiaoChun;SHE HaiDong;LIU ShuangLiang;LI HongTao;ZHANG LiFeng(Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;Innovation Academy for Earth Science,Chinese Academy of Sciences,Beijing 100029,China;Baotou Research Institute of Rare Earth,Baotou 014030,China)
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
2023年第10期2895-2909,共15页
Acta Petrologica Sinica
基金
国家重点研发计划项目(2021YFC2901704)
国家自然科学基金项目(91962103)
中国科学院地质与地球物理研究所重点部署项目(IGGCAS-201901)联合资助.
关键词
稀土-铌-铁矿床
矿化-蚀变元素分布规律
找矿启示
白云鄂博
REE-Nb-Fe deposit
Distribution pattern of mineralization and alteration elements
Exploration inspiration
Bayan Obo
