离子吸附型稀土矿床风化壳地球化学与风化物粒度研究——以姑婆山养民冲稀土矿床为例  

Weathered material granularity and geochemistry of weathering crust in ion-adsorption type REE deposit——A case from Yangminchong of Guposhan

作　　者：苑鸿庆 李社宏[1] 程飞 裴秋明 张有军[1] 孙明行[1] 张海莹[1] 

机构地区：[1]桂林理工大学广西隐伏金属矿产勘查重点实验室,广西桂林541004 [2]山东胜软科技股份有限公司胜软油气勘探开发研究院,山东东营257000 [3]中国地质大学地球科学与资源学院,北京100083

出　　处：《桂林理工大学学报》2015年第2期243-250,共8页Journal of Guilin University of Technology

基　　金：中国地质调查局项目(1212011120354);教育部地质工程中心开放基金项目

摘　　要：离子吸附型稀土矿床是我国稀土矿产的主要开采类型。依据姑婆山地区矿物组合和风化特征，将风化壳细分为6个风化层阶段、3个半风化层阶段。选取典型层面风化样品，分离出〈0．075、0．075～0．150、0．150～0．355和〉0．355mm4类，研究风化壳不同层位和不同粒度风化物中稀土元素的变化特征。研究发现La、Nd、Pr、Sm等轻稀土元素多在风化层富集，元素含量与粒度呈近反比关系，〈0．075mm矿物中稀土比〉0．075mm中相对富集；ce元素从风化壳表层到深部逐渐减少，元素在〈0．075mm中含量相对稳定，〉0．075mm明显减少；Eu元素在半风化层中含量最高，粒度对风化层和半风化层中元素含量影响较大；Gd、Tb、Dy、Y等重稀土元素从风化壳表层到深部逐渐富集，元素在风化物〉0．075mm中含量明显减少。风化壳层位和风化物粒度是影响该地区风化壳中稀土含量的主要因素。Ion-adsorption type REE deposit is the main mining type of rare earth minerals in China.Based on the minerals and weathering characteristics of Guposhan,the weathering crust profile is subdivided into 6 weathered layers and 3 sub-weathed layers.Typical weathering crust specimens are selected as research objects and divided into 4 classes including less than 0.075 mm,0.075 -0.150 mm,0.150 -0.355 mm and more than 0.355 mm.The variation characteristics of REEs in different horizons and the grain size of minerals are studied.The results show that LREE such as La,Nd,Pr and Sm are main enrichment in weathered layer, and there is a close relationship between content and elements grain size.LREE are mainly concentrated in the clay layer with grain size is less than 0.075 mm.Ce element gradually decrease from the surface to deep weath-ering crust,less than 0.075 mm,relatively stable and significantly reduced in more than 0.075 mm.Eu ele-ment is abundant in sub-weathered layer and affected by the grain size of minerals.HREE such as Dy,Y are gradually enriched from the surface to the deep weathering crust,and significantly decreased in more than 0.075 mm.It can be concluded that the content of REE elements in study area is manily affected by the weath-ering horizons and wearhering granularity.

关 键 词：稀土元素 离子吸附型稀土矿床 矿物粒度 风化壳剖面 

分 类 号：P596[天文地球—地球化学]