摘要
稀散金属作为关键战略性矿产资源,对国民经济、国家安全与科技革新具有不可替代的重要作用。其在高新技术、精密制造、清洁能源,以及新一代信息技术等前沿领域,均发挥着核心支撑功能。受地球化学性质的制约,这类元素在自然界中通常呈高度分散状态,难以形成独立矿物,主要作为伴生组分赋存于其他主金属矿物中。在铅锌矿床系统内,闪锌矿被广泛识别为镓(Ga)、锗(Ge)、镉(Cd)和铟(In)等关键稀散元素的重要载体矿物。本文系统梳理了近年来关于铅锌矿床中稀散元素富集规律的研究进展,重点阐释了其赋存状态与富集机制。结果表明:Ga、Ge、Cd和In等元素主要以类质同象形式存在于闪锌矿等硫化物晶格中,独立矿物极为少见且含量甚微。具体而言,Ga、Ge和In倾向于与Cu^(+)、Ag^(+)、Fe^(2+)等离子耦合,共同置换闪锌矿中的Zn^(2+);而Cd则因地球化学行为与Zn高度相似,可直接替代Zn^(2+)进入晶格,从而使闪锌矿成为这些稀散元素最主要的赋存场所。值得注意的是,闪锌矿中铁含量的升高会显著抑制Cd的类质同象置换能力,反映其富集行为受晶体化学环境的明显制约。此外,Ge还可广泛以类质同象形式进入石英等硅酸盐矿物的晶体结构中。从区域成矿背景看,不同成因类型铅锌矿床中稀散元素的含量差异显著,即便在成矿地质条件相似的同一类矿床内,其空间分布亦常呈现较强的非均质性。就富集环境而言,Ga、Ge和Cd更易在低温热液型铅锌矿床中富集;而In则主要富集于与中—高温岩浆热液活动相关或含锡背景的铅锌多金属矿床中。在研究方法上,以电子探针(EPMA)和激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)为代表的现代微区分析技术发挥了关键作用。这些技术凭借其高空间分辨率与原位分析能力,能够精确揭示稀散元素在矿物中的纳米级赋存状态与空间分布,为理解其地球化学行为与富集机制提供了不可替代的技术支撑。未来应进一步聚焦于稀散元素的物质来源识别、在成矿流体中的迁移形式、沉淀机制及其与主金属成矿过程的耦合关系等关键科学问题,以深化对稀散元素超常富集规律的理解,并指导综合勘查与高效利用。
As critical strategic mineral resources,dispersed metals play an irreplaceable role in national economic development,security,and technological innovation.They serve as fundamental supports in cutting-edge fields such as high-tech industries,precision manufacturing,clean energy,and next-generation information technology.Constrained by their geochemical properties,these elements typically occur in a highly dispersed state in nature,seldom forming independent minerals and instead mainly existing as associated components hosted in major metal minerals.Within Pb-Zn deposit systems,sphalerite is widely recognized as a key host mineral for critical dispersed elements such as gallium(Ga),germanium(Ge),cadmium(Cd),and indium(In).This paper systematically reviews recent research advances on the enrichment patterns of dispersed elements in Pb-Zn deposits,with a focus on elucidating their occurrence states and enrichment mechanisms.Studies indicate that elements such as Ga,Ge,Cd,and in primarily occur in an isomorphous form within the crystal lattice of sulfide minerals like sphalerite,while independent minerals are extremely rare and generally negligible in abundance.Specifically,Ga,Ge,and In tend to couple with ions such as Cu+,Ag+,and Fe 2+to jointly replace Zn 2+in sphalerite,whereas Cd,due to its geochemical similarity to Zn,can directly substitute for Zn 2+in the crystal lattice.Consequently,sphalerite becomes the most significant host for these dispersed elements.It is noteworthy that elevated iron content in sphalerite significantly inhibits the isomorphic substitution of Cd,demonstrating the strong influence of crystallochemical conditions on its enrichment behavior.Additionally,Ge can occur isomorphously in silicate minerals such as quartz.From a regional metallogenic perspective,the concentrations of dispersed elements vary considerably among different genetic types of Pb-Zn deposits.Even within deposits of similar geological settings,their spatial distribution often exhibits pronounced heterogeneity.In terms of enrichment environments,Ga,Ge,and Cd are more readily enriched in low-temperature hydrothermal Pb-Zn deposits,whereas In is predominantly concentrated in intermediate-to high-temperature magmatic-hydrothermal systems or tin-bearing polymetallic Pb-Zn deposits.In terms of research methodology,modern microanalytical techniques,particularly electron probe microanalysis(EPMA)and laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS),have played a pivotal role.With their high spatial resolution and in-situ analytical capabilities,these techniques enable precise characterization of the occurrence and spatial distribution of dispersed elements in minerals at the nanoscale,thereby providing indispensable technical support for understanding their geochemical behavior and enrichment mechanisms.Future research should focus on key scientific issues such as identifying the material sources of dispersed elements,understanding their migration forms in ore-forming fluids,clarifying precipitation mechanisms,and deciphering their coupling relationships with the mineralization processes of major metals.Such efforts will deepen the understanding of the super-enrichment mechanisms of dispersed elements and provide theoretical guidance for integrated exploration and efficient utilization.
作者
钱烨
吴澈
罗长海
孙金磊
李华
Qian Ye;Wu Che;Luo Changhai;Sun Jinlei;Li Hua(College of Earth Sciences,Jilin University,Changchun 130061,China;Qinghai Provincial Geological Survey Bureau,Xining 810001,China;MNR Technology Innovation Centre for Exploration and Exploitation of Strategic Mineral Resources in Plateau Desert Region,Xining 810001,China)
出处
《吉林大学学报(地球科学版)》
北大核心
2025年第6期1851-1866,共16页
Journal of Jilin University:Earth Science Edition
基金
国家科技重大专项(2025ZD1006202-3)
青海省省级地质勘查专项基金项目(2023085029ky004)。
关键词
铅锌矿床
闪锌矿
稀散元素
镓
锗
镉
铟
富集规律
Pb-Zn deposits
sphalerite
dispersed elements
gallium
germanium
cadmium
indium
enrichment characteristics
