摘要
南岭地区湖南段是我国重要的钨锡矿产基地,也是锂铌钽等稀有金属聚集区,区内大陆地壳受多期次的沉积、构造、岩浆循环作用而不断趋于成熟,促使锂等金属不断在晚次花岗岩中富集。本文系统梳理了区内各时期花岗岩中锂含量特征及锂矿富集规律,发现从加里东期花岗岩至燕山期花岗岩中锂元素含量平均由25 ppm富集至406 ppm,锂含量呈现逐渐升高的变化趋势,表现为区内锂的地球化学异常与燕山期的花岗岩套合较好,显示出锂矿化与燕山期花岗岩(160—90 Ma)在时空上存在密切联系。通过对成矿地质条件分析,厘定出花岗岩型锂矿(尖峰岭)和云英岩型锂矿(正冲)两类主要锂矿类型。本文认为复式花岗岩结晶分异晚期形成的云英岩和白云母花岗岩顶部是锂成矿有利部位,据此建立了南岭地区湖南段锂矿找矿预测模型。在总结区域花岗岩型锂矿成矿特征的基础上,划分了8处(V1-V8)锂矿成矿远景区,初步预测了南岭地区湖南段锂矿资源潜力达4955100 t,显示出巨大的锂矿成矿潜力,是今后寻找花岗岩型锂矿的主要方向。
The Hunan area of the Nanling region is an important tungsten-tin mineral base in China,as well as an accumulation area of rare metals such as Lithium,Niobium and Tantalum.The continental crust in the area is becoming mature due to multiple periods of sedimentation,structure and magma cycle,which promotes the enrichment of lithium and other metals in late granites.This article systematically summarizes the characteristics of lithium content and the enrichment patterns of lithium deposits in granite from different periods in the area.It is found that the lithium element content in granite from the Caledonian period to the Yanshanian period is enriched from 25 ppm to 406 ppm on average,and the lithium content shows a gradually increasing trend.This is manifested by the geochemical anomalies of lithium in the area,which are well integrated with the Indosinian and Yanshanian granite.It shows a close spatiotemporal connection between lithium mineralization and Yanshanian granite(160-90Ma).By analyzing the geological conditions of mineralization,two main types of lithium deposits have been identified:granite type lithium deposits(Jianfengling)and greisen type lithium deposits(Zhengchong).It is considered that the top of greisen and muscovite granite formed in the late stage of crystallization differentiation of compound granite is the location of lithium mineralization.Based on this,a prediction model for lithium ore prospecting in the Hunan area of the South Range is established.On the basis of summarizing the metallogenic characteristics of regional granite type lithium deposits,eight(V1-V8)lithium mineralization prospects are divided,and it is preliminarily predicted that the potential of lithium resources in the Hunan area of the South Range will reach 4.9551 million tons,showing a huge potential for lithium mineralization,which is the main direction of looking for granite type lithium deposits in the future.
作者
黄建中
孙骥
文春华
陈剑锋
曾广乾
盛丹
许以明
张雄
许若潮
Huang Jianzhong;Sun Ji;Wen Chunhua;Chen Jianfeng;Zeng Guangqian;Sheng Dan;Xu Yimig;Zhang Xiong;Xu Ruochao(Geological Bureau of Hunan Province,Changsha Hunan 410014;Hunan Institute of Geological Survey,Changsha Hunan 410114;Hunan Planning Institute of Land and Resources,Changsha Hunan 410119;Mineral Resources Investigation Institute of Hunan Province;Survey and Monitoring Institute of Hydrogeology and Environmental Geology of Hunan Province,Changsha Hunan 410014)
出处
《国土资源导刊》
2023年第4期10-27,65,共19页
Land & Resources Herald
基金
湖南省重点研发项目(编号:2019SK2261)
中国地质调查局二级项目(编号:DD20230055)
湖南省自然资源厅项目(编号:202208)
湖南省自然资源厅科技计划项目(编号:湘自资科20230102DZ)
湖南省地质院科研项目(编号:HNGSTP202302,HNGSTP202306)。
关键词
花岗岩型锂矿
成矿特征
矿产资源预测
南岭地区湖南段
granite-type Li deposits
metallogenic characteristics
mineral resources prediction
Hunan area of the Nanling region
