江西松树岗花岗岩型铌钽矿床的成矿机制及找矿方向  

Metallogenic mechanism and prospecting direction of Songshugang granite-type niobium-tantalum deposit in Jiangxi Province

作　　者：诸泽颖 王汝成[2,3] 王登红[1] 李建康[1] 任建国 ZHU ZeYing;WANG RuCheng;WANG DengHong;LI JianKang;REN JianGuo(Key Laboratory of Metallogeny and Mineral Resource Assessment,Ministry of Natural Resources,Institute of Mineral Resource,Chinese Academy of Geological Sciences,Beijing 100037,China;State Key Laboratory for Mineral Deposits Research,School of Earth Sciences and Engineering,Nanjing University,Nanjing 210023,China;Frontiers Science Center for Critical Earth Material Cycling,Nanjing University,Nanjing 210023,China;Jiangxi Ganfeng Lithium Group Co.,LTD.,Xinyu 338004,China)

机构地区：[1]自然资源部成矿作用与资源评价重点实验室,中国地质科学院矿产资源研究所,北京100037 [2]南京大学内生金属矿床成矿机制研究国家重点实验室,南京大学地球科学与工程学院,南京210023 [3]南京大学关键地球物质循环教育部前沿科学中心,南京210023 [4]江西赣锋锂业集团股份有限公司,新余338004

出　　处：《岩石学报》2024年第9期2786-2802,共17页Acta Petrologica Sinica

基　　金：国家自然科学基金项目(41902037、42330806);中国地质调查局项目(DD20221695、DD20190379、DD20230289、DD20230034);国家重点研发计划(2022YFC2905301)联合资助.

摘　　要：江西松树岗花岗岩型铌钽矿床位于江西省上饶市葛源镇,不仅是华南最大花岗岩型钽矿床,同时还共伴生有铌、铷、锂、钨、锡等多金属。松树岗花岗岩型铌钽矿床近地表产出石英脉型钨锡矿,深部隐伏为花岗岩型铌钽矿床。花岗岩体具有垂向分带性,深部为花岗岩主体黄玉钠长石花岗岩,垂向向上依次为云英岩化花岗岩、钾长石花岗岩以及似伟晶岩壳。花岗岩具有特征的“雪球结构”,斑晶为石英或钾长石。松树岗铌钽矿床岩体产出铌钽氧化物(包括铌铁矿、钽铁矿、锡锰钽矿等)、锆石、锡石以及黑钨矿。铌铁矿原位U-Pb定年结果显示成矿年龄约为130Ma。铌钽氧化物、锆石、锡石等副矿物常显示明显的核边结构,其中铌钽氧化物核部为铌铁矿,边部为钽铁矿和锡锰钽矿,记录岩体经历了明显的岩浆-热液多阶段成矿过程。松树岗花岗岩云母以铁锂云母为主,Li_(2)O含量为2.89%~4.29%。主体钠长石花岗岩中铁锂云母可分为片状铁锂云母(Znw1)和细粒铁锂云母(Znw2),其中片状铁锂云母(Znw1)同样具有环带结构,且环带主要由Rb含量变化导致。片状铁锂云母核部Rb 2O为0.9%~1.16%,边部Rb 2O含量升高,最高可达4.08%。细粒铁锂云母(Znw2)分布于基质中,含有较高的Ta含量(110×10^(-6))。云英岩中出现束状或放射状产出的铁锂云母(Znw3),具有较高的Sn含量(464×10^(-6))。片状铁锂云母核边结构记录岩浆演化过程,云英化花岗岩中的铁锂云母为热液成因。松树岗花岗岩型铌钽矿床是一个高演化稀有金属花岗岩,造岩矿物铁锂云母和副矿物铌钽氧化物记录岩体经历了岩浆到热液阶段演化的过程。地表石英脉型钨锡矿以及岩体中特征的“雪球结构”是重要的高演化稀有金属花岗岩重要的找矿标志。松树岗岩体位于著名的灵山杂岩体周围,灵山岩体的边缘仍然具有出露有类似稀有金属矿床的可能,�The Songshugang granite-type Nb-Ta deposit is located in the Geyuan Town,Shangrao City,Jiangxi Province.It is not only the largest granite-type tantalum deposit in South China,but also a reservoir of Nb,Rb,Li,W,and Sn.The Songshugang granite consists of quartz-vein type tungsten-tin at the surface,and the granite-type niobium-tantalum deposit is deeply buried.The granite body displays vertical zonation,with topaz albite granite as the main body of granite in the deep,and in the vertical sequence of greisenization granite,K-feldspar granite and pegmatite.All the granite are featured by typical“snowball texture”with quartz and K-feldspar as phenocryst.The accessory minerals include columbite group minerals(columbite,tantalite and wodginite),zircons,cassiterites and ferberite.The in situ columbite U-Pb dating result reveals the mineralization age is ca.130Ma.Nb-Ta oxides are intergrowth with zircons and cassiterite,and display evident core to rim zonation,where the core is classified as columbite-(Fe)and the rim consists of tantalite and wodginite.This zonation records the whole suite has experienced magmatic to hydrothermal process.The zinnwaldite is the dominant micas in the Songshugang granite,with the Li_(2)O varying from 2.89%to 4.29%.In the main topaz albite granite,both the large zinnwaldite(Znw1)and fine-grained zinnwaldite(Znw2)is present.The former Znw1 exhibits the zonation texture resulting from the variation of Rb contents.The Rb 2O is 0.9%to 1.16%at the core while the rim sharply increases to 4.08%.Fine-grained zinnwaldite(Znw2)distribute in the matrix associated with albite,and contain the highest Ta(110×10^(-6)).In the greisen,the radiation(or clusters)zinnwaldite(Znw3)is featured as the highest Sn content(464×10^(-6)).The core-rim texture of zinnwaldite in granite records the magmatic fractionation process and the zinnwaldite in greisen is of hydrothermal origin.All the mineralogical textures show the Songshugang granite is highly evolved.The quartz veins-type W-Sn at the surface and“snowbal

关 键 词：铌钽矿床 松树岗岩体 花岗岩型 成矿机制 

分 类 号：P611.11[天文地球—矿床学] P618.79[天文地球—地质学] P618.86