广西大瑶山中北部四方山地区云英岩型铷矿化特征与找矿评价  

Mineralization characteristics and prospecting evaluationof greisen type rubidium deposit in Sifangshan area,central and northern Dayaoshan,Guangxi

作　　者：孙兴庭 张凤英 谢植贵 SUN Xingting;ZHANG Fengying;XIE Zhigui(Geological Survey Institute of Guangxi Zhuang Autonomous Region,Nanning 530023,Guangxi,China;Geology and Mineral Testing Research Center of Guangxi Zhuang Autonomous Region,Nanning 530023,Guangxi,China)

机构地区：[1]广西壮族自治区地质调查院,广西南宁530023 [2]广西壮族自治区地质矿产测试研究中心,广西南宁530023

出　　处：《矿产与地质》2022年第3期496-502,515,共8页Mineral Resources and Geology

基　　金：广西壮族自治区第八批自治区级人才小高地“广西关键矿产资源深部勘查人才小高地项目”(桂组通字[2019]85);广西地质矿产勘查开发局部门前期勘查项目(桂地矿地[2021]11号)共同资助。

摘　　要：首次在大瑶山中北部四方山地区发现云英岩型铷铍锂矿化,主要为赋存于NWW和NNW向断裂中的云英岩充填破碎带和NE向裂隙带中的云英岩脉。铷矿化普遍且品位变化小[w(RbO)=0.05%~0.25%],主要存在于云母类矿物中。云英岩属石英-黄玉-云母类型,地球化学特征上具高铝富碱特征,与邻近的湘南和栗木地区云英岩和云英岩化花岗岩特征相似,为岩浆期后-热液交代作用的产物。矿化和蚀变特征表明,本区可能经历了相对完整的岩浆-热液演化过程,且与云英岩脉和普遍存在的云母线脉共同指示剥蚀尚浅而又离云英岩型或岩体型矿床(尤其是锡矿)不远,中浅部即有可能揭露到锡钨和铌钽等稀有金属矿床。综合分析推测大瑶山中北部沿金秀—昭平—水口—上洞一线存在一条与南岭地区近EW向的花岗岩带类似的岩浆岩带,且具有较大的锡钨-稀有金属矿找矿前景。Rb-Be-Li mineralization of greisen rock type is discovered for the first time in Sifangshan area,Central-North Dayaoshan,which is mainly hosted at greisen rock-filled fractured zone in the NWW and NNWtrending faults,and greisen rock vein in NE-trending fracture zones.Rubidium mineralization is widespread with a small grade variation(w(RbO)=0.05%-0.25%)and is found mainly in mica minerals.The greisen rock belongs to quartz-topaz-mica type,with high aluminum and alkali-rich geochemical characteristics,which is similar to that of greisen rock and greisenization granite in the adjacent South Hunan and Limu area,and it is the product of post-magmatic-hydrothermal metasomatism.The characteristics of mineralization and alteration indicates that this area might have undergone a relatively complete magmatic-hydrothermal process,and together with the greisen vein and the ubiquitous mica line veins,it is shown that the denudation is still shallow and not far away from the greisen rock type or rock mass type deposit,especially tin deposit.It is possible to expose the deposit of tin-tungsten and niobium-tantalum rare metals in the middle and shallow parts.According to the comprehensive analysis,it is inferred that there is a magmatic rock belt along the Jinxiu-Zhaoping-Shuikou-Shangdong area of North-Central Dayaoshan,which is similar to the nearly-EW granite belt in the Nanling area.There is a great exploration prospect for tin-tungsten-rare metal deposit in the above area.

关 键 词：铷矿 云英岩型 找矿评价 四方山地区 大瑶山中北部 

分 类 号：P618.77[天文地球—矿床学]