摘要
赣南铁山垅钨矿田位于南岭钨锡多金属成矿带东段,已探获黑钨矿资源量超10万吨。铁山垅复式岩体包括主体似斑状黑云母花岗岩和补体细粒二云母花岗岩两部分,花岗斑岩呈脉状分布。矿田内花岗岩具有相似的地球化学特征,都属过铝质高钾钙碱性花岗岩类,表现出高硅、富铝、富碱、高钾、富成矿元素(W、Sn、Cu、Mo)和亏损Ba、Sr、Ti、P、REE、Eu,稀土配分曲线呈典型的“海鸥式”分布和M型四分组效应等特征。利用LA-ICP-MS锆石U-Pb定年方法获得花岗斑岩^(206)Pb/^(238)U年龄为146.7±0.5 Ma(MSDW=0.5),成岩时代属晚侏罗世。锆石的n(^(176)Lu)/n(^(177)Hf)=0.000973~0.001989,f_(Lu/Hf)=-0.97~-0.94,ε_(Hf)(t)=-17.9~-10.3,二阶段模式年龄(TDM2)为1.86~2.33 Ga,显示原岩为古元古代地壳。综合分析认为,铁山垅矿田岩浆活动可划分为170~155 Ma、155~150 Ma、150~145 Ma三个阶段,钨锡矿成矿主要集中在第二阶段,且第三阶段花岗斑岩与铜多金属矿成矿关系密切,推测铜岭矿区深部具有较大的找矿前景。
Tieshanlong tungsten ore field is located in the eastern section of Nanling W—Sn—polymetallic metallogenic belt,which have produced more than 100 kt of wolframite around the Tieshanlong granitic complex.There have three kinds of granites:the early coarse-grained porphyritic biotite granite,the complement fine grained muscovite granite and latest granite porphyry veins,showing common geochemical characteristics of peraluminous,high-K and calc-alkali category,integrated with enrichments of SiO_(2),Al_(2)O_(3),K_(2)O,W,Sn,Cu,Mo,depletions of Ba,Sr,Ti,P,REE and Eu negative anomaly.The REE distribution curve shows a typical“seagull”distribution with M-type tetrad effect.LA-ICP-MS zircon U-Pb dating of granite porphyry yields emplacement age of 146.7±0.5 Ma(MSDW=0.5),with n(^(176)Lu)/n(^(177)Hf)and f_(Lu/Hf)rations of 0.000973~0.001989 and-0.97~-0.94,respectively.Theε_(Hf)(t)values range from-17.9 to-10.3,and TDM2 are 1.86 Ga to 2.33 Ga,indicating primary reworking of the Paleoproterozoic crustal material.The comprehensive analysis shows that Tieshanlong ore field have three stages magmatic activities of 170~155 Ma,155~150 Ma and 150~145 Ma,and the W—Sn mineralization is mainly occurred in the second stage.Granite porphyry is rich in Cu,Mo and W,which is closely related to the Cu—W—polymetallic mineralization,and show a great prospecting potential in the deep part of Tongling deposit.
作者
李伟
唐菊兴
鲁捷
郭娜
袁慧香
连敦梅
LI Wei;TANG Juxing;LU Jie;GUO Na;YUAN Huixiang;LIAN Dunmei(College of Earth Sciences,Chengdu University of Technology,Chengdu,610059;The Seventh Geological Brigade of Jiangxi Bureau of Geology,Key Laboratory of Ionic Rare Earth Resources and Environment,Ganzhou,Jiangxi,341000;MNR Key Laboratory of Metallogeny and Mineral Resource Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing,100037;Development Research Center of China Geological Survey,Beijing,100037)
出处
《地质论评》
CAS
CSCD
北大核心
2024年第1期175-188,共14页
Geological Review
基金
国家重点研发计划项目(编号:2021YFC2901702)
江西省财政出资地质勘查项目(编号:20210041、20220014)的成果。
