龙南上黄湾稀土矿地质特征及成矿条件分析

摘要

Longnan County is rich in rare earth element (REE) resources,where REE deposit of ion-adsorption type is firstly found out in the weathering crust of granite.In this study,the internal and external geological conditions of Shanghuangwan REE deposit in Longnan Conuty are analyzed and studied systematically.The result indicates that the formation of the REE deposit is related to the medium-fine-grainedbiotite granite of high REE content (up to 406.65 × 10-6)in Yanshan period.The REE distribution model of mother rock is similar to light REE distribution type of low yttrium and low europium.Under warm and humid climate weather conditions in the specific tectonic location,as the ore-bearing mother rocks are weathering and leaching,light REE deposit is enriched and formed in the whole weathered layer of granite.%龙南县是首次发现花岗岩风化壳离子吸附型稀土矿的地区,具有丰富的稀土资源.通过对龙南上黄湾稀土矿成矿内生与外生地质条件进行系统的分析研究,结果显示该稀土矿床的形成与燕山期的高稀土含量(达406.65×10-6)的中细粒黑云母花岗岩有关,母岩的稀土配分模式为低钇低铕轻稀土配分型,在特定的构造位置和温暖潮湿气候条件下,含矿母岩经风化淋滤作用后,在花岗岩全风化层中富集形成轻稀土矿床.