浅论湘东北地区与燕山期花岗岩有关矿床的成矿系列与找矿方向  

A Preliminary Study of Metallogenic Series and Its Prospecting Direction Related to Yanshannian Granites in Northeastern of Hunan Province

作　　者：陈剑锋 黄建中[2] 文春华 张锦煦 彭薇 李胜苗 曹创华 安江华 CHEN Jian-feng;HUANG Jian-zhong;WEN Chun-hua;ZHANG Jin-xu;PENG Wei;LI Sheng-miao;CAO Chuang-hua;AN Jiang-hua(Geological Survey Institute of Hunan Province,Changsha,Hunan 410116;Geological Bureau of Hunan Province,Changsha,Hunan 410014;Geophysical and Geochemical Survey Institute of Hunan,Changsha,Hunan 410116;Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring of Ministry of Education,Central South University,Changsha,Hunan 410083)

机构地区：[1]湖南省地质调查所,湖南长沙410116 [2]湖南省地质院,湖南长沙410014 [3]湖南省地球物理地球化学调查所,湖南长沙410116 [4]中南大学,有色金属成矿预测与地质环境监测教育部重点实验室,湖南长沙410083

出　　处：《地球学报》2023年第5期815-833,共19页Acta Geoscientica Sinica

基　　金：湖南省地质院科研项目(编号:HNGSTP202306;HNGSTP202302;HNGSTP202105);中国地质调查局二级项目(编号:DD20230055,DD20221695-16);湖南省重点领域研发计划资助项目(编号:2019SK2261);湖南省自然资源厅科技计划项目(编号:20230102DZ)联合资助。

摘　　要：湘东北地区是华南重要的Au、Cu、Co、Pb、Zn、W等多金属以及Nb、Ta、Li等稀有金属的矿集区之一,区内的(稀有)多金属矿床在空间展布及形成时间上显示与燕山期花岗岩关系密切。本文在系统梳理前人研究成果的基础上,将湘东北地区燕山期花岗岩有关的(稀有)多金属矿床厘定为一个成矿系列以及6个成矿亚系列。与早燕山期侵入岩有关的铜多金属矿床成矿亚系列(Ⅰ)的成矿岩体为石英斑岩,为壳幔同熔的产物。与晚燕山期侵入岩有关的各成矿亚系列(Ⅱ~Ⅵ)均与该区伸展拉张环境下深部地壳重熔形成的幕阜山和连云山花岗岩体有关,其中锂铌钽等稀有金属成矿亚系列(Ⅱ)属二云母二长花岗岩分异出的伟晶岩型矿床;幕阜山岩体的酸性花岗岩岩浆所分异的成矿流体为钨多金属成矿亚系列(Ⅲ)和铅锌多金属矿床(亚系列Ⅳ)提供了成矿物源;连云山岩体花岗岩浆的上涌,通过萃取元古宙地层中成矿元素以及致早期区域构造的重新活化,为钴铜多金属成矿亚系列(Ⅴ)以及金多金属成矿亚系列(Ⅵ)提供了成矿物源及矿质的运移、储存空间。依据区域成矿规律和“缺位找矿”理论,本文认为长平大断裂南端是寻找钴铜矿的有利地段,湘东北地区具备良好的稀有金属及金等矿床的找矿前景。The northeastern Hunan Province is an important area of polymetallic(Au,Cu,Co,Pb,Zn,W)and rare-metal(Nb,Ta,Li)ore concentration in South China.The spatio-temporal distribution of polymetallic deposits and Yanshannian granites shows that the mineralization in the study area has a genetic relationship with granitoids.Based on previous studies,we hypothesize that these deposits belong to a single metallogenic series:the polymetallic(rare-metal)ore-deposit minerogenetic series related to the Yanshannian intrusion,which can be subdivided into six subseries of ore deposits.The Cu polymetallic deposit subseries(Ⅰ)associated with Early Yanshannian intrusive rocks,which is genetic realted to quzrtz porphyry orgined from Mantal-Crust interaction.The others deposit subseries(Ⅱ-Ⅵ)associated with Late Yanshannian intrusive rocks,are genetic realted to Lianyuanshan and Mufushan granitic batholith,which derived from partial melting of metasedimentary basement in an extensional tectonic setting.The Li-Nb-Ta rare-metal deposit subseries(Ⅱ)is pegmatite-type deposit formed by differentiation of two-mica monzogranite.The ore metals of the W polymetallic deposit subseries(Ⅲ)and Pb-Zn polymetallic deposit subseries(Ⅳ)were directly derived from the Mufushan granites.The ore-frrming material extracted from basement and tectonic reactivated when magma upwilling in the Lianyunshan area,supplied ore metals and migration channels for Co-Cu polymetallic deposit subseries(Ⅴ)and Au polymetallic deposit subseries(Ⅵ).Based on regional metallogenetic and“absence prospecting”theroies,this paper argue that the southern region of Changsha-Pingjiang fault has excellent prospecting for Co-Cu deposits,and the northeastern of Hunan Province showing good Au and rare-metal searchingprospects.

关 键 词：多金属矿床 成矿系列 找矿方向 燕山期花岗岩 湘东北地区 

分 类 号：P612[天文地球—矿床学]