摘要
稀土元素是白云鄂博矿床最有特色的矿产。本文在详细讨论了稀土矿物氧、碳同位素制样方法的基础上，对矿床中晚期脉、白云石型矿石、萤石型矿石中的主要稀土矿物进行了系统的氧、碳同位素分析。其中，晚期脉中的氟碳酸盐矿物的碳、氧同位素值较低，具有幔源热液结晶的特点；白云岩型矿石中氟碳铈矿δ１３Ｃ在－１．１‰～－３．４‰，δ１８Ｏ在８．６‰～１２．０‰；独居石δ１８Ｏ在５．７‰～１１．４‰，磷灰石δ１８Ｏ在６．３‰～９．４‰；萤石型矿石中氟碳铈矿δ１３Ｃ在－５．２‰～－５．８‰，δ１８Ｏ在３．６‰～５．５‰；独居石δ１８Ｏ在３．５‰～４．５‰。结合矿床地质特征分析，矿区萤石型矿石和晚期脉的形成可能与深源热液有关；
REE minerals are the most characteristic ore resources in the Bayan Obo ore deposit. Based upon a detailed discussion on the analytical procedure for determining isotopic compositions of REE minerals, the authors studied some main REE minerals from the late stage veins, banded fluorite ores and dolomite ores. Fluor carbonate minerals from the late stage veins have relatively low carbon and oxygen isotopic values, implying an involvement of mantle derived solution. Oxygen isotopes vary in the range of 8 6‰～12 0‰ for bastnaesite,5 7‰～11 4‰ for monazite, and 6 3‰～9 4‰ for apatite from dolomite ores; 3 6‰～5 5‰ for bastnaesite, and 3 5‰～4 5‰ for monazite from banded fluorite ores. δ 13 C values are -1 1‰～-3 4‰ and -5 8‰～-5 2‰ for bastnaesite from dolomite ores and that from banded fluorite ores respectively. Based on these data together with an analysis of the geological features of the ore deposit, it is held that the formation of banded fluorite ores and late stage veins in the ore district might have had to do with deep source hydrothermal solution, whereas REE are characterized by multi source multiphase mineralization.
出处
《矿床地质》
CAS
CSCD
北大核心
1997年第1期31-40,共10页
Mineral Deposits
基金
国家自然科学基金
中国科学院矿床地球化学开放实验室联合资助
