广西六陈岩体与离子吸附型稀土矿成矿及成因

The Study on Mineralization and Origin of Rock Mmass and ion-absorbed Rare Earth Ore in Liuchen Guangxi

六陈岩体富K、Si,贫Ca、Mg,属SiO2、Al过饱和系列,偏碱性.岩体稀土元素总量（∑REE）315.5×10-6,高于维氏值292×10-6.岩体风化强烈,一般形成20～30m的风化壳,风化壳稀土含量高,矿厚一般为4～8m,为混合型稀土矿.离子吸附型稀土矿主要以离子吸附相形式赋存于花岗岩风化壳的全风化层中.文章通过对六陈岩体特征及离子吸附型稀土矿矿床特征初步探讨了其成因,认为六陈岩体稀土元素的高丰度值是离子吸附型稀土矿成矿的必要条件,并与相对稳定的构造环境及有利的地形地貌和气候条件密切相关.

Rich in K and Si, but poor in Ca and Mg, Liuchen rock mass belongs to Si02,A1 supersaturated series and is alkaline. Its total REE content is 315.5x10, which is over Vickers number 292x10. Strong weathering of the rock mass lead to the formation of a weathering crust that are of 20 to 30 meters and that have a high content rare earth. Usually 4 to 8 meters thick, these ores are hybrid rare earth minerals. Mainly in the form of ionic adsorption, ion-absorbed rare earth ore hosts in the completely weathering layer of granite weathering crust. After preliminarily discussing the origins of Liuchen rock mass according to the characteristics of Liuchen rock mass and ion-absorbed rare earth ore deposits, we conclude that the high abundance value of rare earth elements of Liuchen rock mass is a necessary condition for the formation of ion-absorbed rare earth ore and has a close relationship with relatively stable tectonic settings and the advantageous landform and climate.