摘要
广东省是全国重要的离子吸附型稀土矿床产地。本文系统总结了离子吸附型稀土矿床成矿母岩的特征,重点分析了母岩的稀土元素特征,提出了离子吸附型稀土矿床的快速评价指标。通过岩石学特征分析,发现成矿母岩主要有6期,以晚侏罗世黑云母(二长)花岗岩为主。根据矿床地质特征、副矿物等研究推测,离子吸附型稀土矿床中稀土元素有相当一部分是以离子态存在于硅酸盐矿物中。稀土元素特征研究表明,轻稀土与重稀土矿床(点)母岩的稀土元素球粒陨石配分模式相似,推测两类矿床(点)稀土元素未发生明显分异;不同时代岩体的稀土元素配分曲线类似,推测其成矿母岩来源或形成背景基本一致。离子吸附型稀土矿床可形成明显的水系沉积物异常,La、Y异常及La/Y可作为快速评价稀土矿床类型及配分类型的重要指标。
Numerous economically significant ion-adsorption type rare earth element(REE)deposits mainly occur in the Guangdong Province,China.We have analyzed the geological characteristics and REE behaviors of parent rocks responsible for these ion-adsorption type REE deposits,and then proposed a rapid evaluation index for this deposit type.Based on the petrological characteristics,there are six major epochs of parent rocks,mainly the late Jurassic intrusive rocks,in which biotite(-monzonite)granites are mostly common.Combined with deposit geology and accessory minerals,it is speculated that a considerable amount of REE are present in silicate minerals as ionic state in these ion-adsorption type REE deposits.The chondrite-normalized REE patterns of parent rocks in the light and heavy REE deposits(occurrences)are similar,and it is suggested that there is no obvious differentia⁃tion of REEs between them.In addition,the similar distribution curves of REEs in the parent rocks of different formation ages indicate that they shared a common source and/or formed in a broadly same environment.The significant drainage sediment anomalies maybe result from adsorption-type REE deposits,therefore,La and Y anomalies and La/Y values can potentially be used as an important index to quickly evaluate the ores and types of REE deposits.
作者
王涌泉
汪礼明
刘东宏
汪汝澎
欧阳志侠
WANG Yongquan;WANG Liming;LIU Donghong;WANG Rupeng;OUYANG Zhixia(Geology Bureau for Nonferrous Metal of Guangdong Province,Guangzhou 510080,Guangdong,China;Guangdong Nonferrous Geological Exploration Institute,Guangzhou 510080,Guangdong,China)
出处
《矿产勘查》
2023年第12期2341-2351,共11页
Mineral Exploration
基金
广东省稀土资源与环境风险项目(2019B030302013)资助。
关键词
离子吸附型稀土矿床
稀土元素
成矿母岩
评价指标
广东省
ion-adsorption type rare earth element deposit
rare earth element
ore-forming parent rock
evaluation index
Guangdong Province
