首页 > 最新文献

Journal of Geochemical Exploration最新文献

英文 中文
Corrigendum to “Molybdenum and gold distribution variances within Iranian copper porphyry deposits” [J. Geochem. Explor. 261 (June 2024) 107471] “伊朗铜斑岩矿床中钼和金的分布差异”[J]。Geochem。探索者号。261(2024年6月)107471]
IF 3.3 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-12-01 Epub Date: 2025-07-11 DOI: 10.1016/j.gexplo.2025.107854
Seyed Mehran Heidari , Peyman Afzal , Behnam Sadeghi
{"title":"Corrigendum to “Molybdenum and gold distribution variances within Iranian copper porphyry deposits” [J. Geochem. Explor. 261 (June 2024) 107471]","authors":"Seyed Mehran Heidari , Peyman Afzal , Behnam Sadeghi","doi":"10.1016/j.gexplo.2025.107854","DOIUrl":"10.1016/j.gexplo.2025.107854","url":null,"abstract":"","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"279 ","pages":"Article 107854"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145018552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A review of Australian carbonatites and associated REE-Nb mineralisation 澳大利亚碳酸盐岩及其伴生REE-Nb矿化研究综述
IF 3.3 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-12-01 Epub Date: 2025-09-05 DOI: 10.1016/j.gexplo.2025.107870
Ross Chandler , Ignacio González-Álverez , John Mavrogenes , Luke Blais
Australia has 16 known carbonatites, and two other occurrences of REE mineralisation interpreted as carbonatite-related. These are all located within Precambrian crust, and host known resources of c. 7.2 Mt. of rare earth oxides (containing c. 1.73 Mt. of Nd2O3 and Pr6O11), and c. 2.7 Mt. of Nb2O5.
Australia's carbonatites range from Neoarchean to Jurassic, and display extreme diversity in geological characteristics, ranging from large, multiphase intrusive complexes dominated by either carbonatite (e.g. Gifford Creek and Mt. Weld, Western Australia) or silicate rocks (e.g. Cummins Range and Cundeelee, Western Australia), to single phase and small volume carbonatite dykes (e.g. Yungal dykes, Western Australia). Studied occurrences show similarly diverse radiogenic isotopic signatures (Rb/Sr and Sm/Nd), indicating derivation from a variety of mantle sources ranging from HIMU through to EM1.
Significant rare earth element (REE) and niobium (Nb) mineralisation occurs in both fresh and weathered carbonatites throughout Australia, with markedly different mineralogical and grade characteristics. While weathering history and preservation are crucial to the formation of supergene enrichments in REE and Nb, analysis of whole-rock geochemical data for different carbonatite types from the Mt. Weld and Gifford Creek complexes suggest primary magmatic composition plays the strongest determinant in the magnitude of grade increase, with siderite-dominated carbonatites having less potential for supergene upgrade than dolomite, ankerite and calcite-dominated examples.
The distinct geophysical signatures of Australia's known carbonatites have aided exploration efforts leading to early discoveries of deposits within highly magnetic complexes such as Mt. Weld and Cummins Range. Recent discoveries of geophysically subtle complexes (e.g. Gifford Creek complex, West Arunta) suggests both alternative geophysical techniques and a comprehensive structural understanding are crucial to discovery.
Explorers should focus on areas of known carbonatite magmatism, with a particular focus on developing an understanding of the regional structures that can facilitate carbonatite intrusion. On a local scale, the selection of relevant carbonatite geophysical and exploration signatures leveraging previous local discoveries should be prioritised. The small number of known carbonatites in Australia compared to the other continents abundances indicates further carbonatites and associated mineralisation may be discovered with increased exploration.
澳大利亚有16个已知的碳酸盐岩,另外两个稀土矿化被解释为与碳酸盐岩有关。这些地区均位于前寒武纪地壳内,稀土氧化物(Nd2O3和Pr6O11)已知资源量约7.2 mt, Nb2O5已知资源量约2.7 mt。澳大利亚的碳酸盐岩范围从新太古代到侏罗纪,地质特征极其多样,既有以碳酸岩(如西澳大利亚的Gifford Creek和Mt. Weld)或硅酸盐岩(如西澳大利亚的Cummins range和Cundeelee)为主的大型多期侵入杂岩,也有单相小体积碳酸岩岩脉(如西澳大利亚的Yungal岩脉)。研究的矿床显示出同样多样化的放射性成因同位素特征(Rb/Sr和Sm/Nd),表明衍生自从HIMU到EM1的各种地幔源。在澳大利亚各地的新鲜和风化碳酸盐中都存在显著的稀土元素(REE)和铌(Nb)矿化,它们具有明显不同的矿物学和品位特征。虽然风化历史和保存对稀土和铌表生富集的形成至关重要,但对Mt. Weld和Gifford Creek杂岩不同类型碳酸盐岩的全岩地球化学数据分析表明,原生岩浆成分在品位增加幅度方面起着最重要的决定作用,以菱铁矿为主的碳酸盐岩的表生升级潜力小于以白云岩、铁白云岩和方解石为主的碳酸盐岩。澳大利亚已知碳酸盐岩的独特地球物理特征有助于勘探工作,导致在Mt. Weld和Cummins Range等高磁性复合体中早期发现矿床。最近发现的地球物理上微妙的复合体(例如,西Arunta的Gifford Creek复合体)表明,替代的地球物理技术和全面的结构理解对发现至关重要。勘探人员应该把重点放在已知的碳酸盐岩岩浆活动区域,特别要注意发展对可能促进碳酸盐岩侵入的区域结构的理解。在局部范围内,应优先考虑利用以前的局部发现选择相关的碳酸盐岩地球物理和勘探特征。与其他大陆的丰度相比,澳大利亚已知的碳酸盐岩数量较少,这表明随着勘探的增加,可能会发现更多的碳酸盐岩和相关的矿化作用。
{"title":"A review of Australian carbonatites and associated REE-Nb mineralisation","authors":"Ross Chandler ,&nbsp;Ignacio González-Álverez ,&nbsp;John Mavrogenes ,&nbsp;Luke Blais","doi":"10.1016/j.gexplo.2025.107870","DOIUrl":"10.1016/j.gexplo.2025.107870","url":null,"abstract":"<div><div>Australia has 16 known carbonatites, and two other occurrences of REE mineralisation interpreted as carbonatite-related. These are all located within Precambrian crust, and host known resources of c. 7.2 Mt. of rare earth oxides (containing c. 1.73 Mt. of Nd<sub>2</sub>O<sub>3</sub> and Pr<sub>6</sub>O<sub>11</sub>), and c. 2.7 Mt. of Nb<sub>2</sub>O<sub>5</sub>.</div><div>Australia's carbonatites range from Neoarchean to Jurassic, and display extreme diversity in geological characteristics, ranging from large, multiphase intrusive complexes dominated by either carbonatite (e.g. Gifford Creek and Mt. Weld, Western Australia) or silicate rocks (e.g. Cummins Range and Cundeelee, Western Australia), to single phase and small volume carbonatite dykes (e.g. Yungal dykes, Western Australia). Studied occurrences show similarly diverse radiogenic isotopic signatures (Rb/Sr and Sm/Nd), indicating derivation from a variety of mantle sources ranging from HIMU through to EM1.</div><div>Significant rare earth element (REE) and niobium (Nb) mineralisation occurs in both fresh and weathered carbonatites throughout Australia, with markedly different mineralogical and grade characteristics. While weathering history and preservation are crucial to the formation of supergene enrichments in REE and Nb, analysis of whole-rock geochemical data for different carbonatite types from the Mt. Weld and Gifford Creek complexes suggest primary magmatic composition plays the strongest determinant in the magnitude of grade increase, with siderite-dominated carbonatites having less potential for supergene upgrade than dolomite, ankerite and calcite-dominated examples.</div><div>The distinct geophysical signatures of Australia's known carbonatites have aided exploration efforts leading to early discoveries of deposits within highly magnetic complexes such as Mt. Weld and Cummins Range. Recent discoveries of geophysically subtle complexes (e.g. Gifford Creek complex, West Arunta) suggests both alternative geophysical techniques and a comprehensive structural understanding are crucial to discovery.</div><div>Explorers should focus on areas of known carbonatite magmatism, with a particular focus on developing an understanding of the regional structures that can facilitate carbonatite intrusion. On a local scale, the selection of relevant carbonatite geophysical and exploration signatures leveraging previous local discoveries should be prioritised. The small number of known carbonatites in Australia compared to the other continents abundances indicates further carbonatites and associated mineralisation may be discovered with increased exploration.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"279 ","pages":"Article 107870"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144996910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Mineral system modeling of Lithium-Cesium-Tantalum (LCT)-type pegmatites: Regional-scale exploration targeting and uncertainty analysis in the Sanandaj-Sirjan zone, Western Iran 锂-铯-钽(LCT)型伟晶岩矿物系统建模:伊朗西部Sanandaj-Sirjan地区区域尺度勘探目标与不确定性分析
IF 3.3 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-12-01 Epub Date: 2025-08-24 DOI: 10.1016/j.gexplo.2025.107885
Majid Keykhay-Hosseinpoor , Alok Porwal , R. Kalimuthu , Shanta Panja
Granitic pegmatites, particularly lithium‑cesium‑tantalum (LCT) types, are vital sources of rare metals crucial for modern technologies, including sustainability, energy storage, and green energy applications. Exploring and targeting LCT pegmatites are essential to meet the increasing demand for critical metals like lithium in green technologies. Mineral prospectivity modeling provides a systematic approach to identifying these deposits, especially in regions such as western Iran, where the Sanandaj-Sirjan Zone (SaSZ) is the potential host of LCT pegmatites. This study aims to model the prospectivity of LCT pegmatites in the SaSZ, with three primary objectives: (i) to construct a mineral systems framework that defines the critical processes controlling the genesis of LCT pegmatites and their mappable proxies, (ii) to identify high-priority exploration targets using knowledge-driven approaches, and (iii) address uncertainties stemming from limited data availability (epistemic) and from the integration of multiple models (systemic) to improve exploration reliability. To achieve these objectives, three well-known knowledge-based algorithms—fuzzy inference systems, continuous fuzzy gamma, and geometric average—were employed using publicly available geo-exploration datasets to generate prospectivity models based on the mineral systems approach. These were subsequently combined into a final predictive model using a majority voting (MV) ensemble technique. A confidence index (CI) was incorporated to quantify and mitigate uncertainties associated with the multi-algorithm approaches, delineating low-risk, high-confidence zones for future exploration. The results show high prospectivity zones (~2 % of the study area) in the northern and southern parts of the SaSZ, particularly near the Alvand complexes, predominantly located farther from their host plutons and within metamorphic aureoles. This study highlights the efficacy of integrating mineral systems frameworks with geospatial modeling to optimize exploration strategies. Future research should prioritize acquiring high-resolution geophysical and geochemical data and conducting systematic ground-truthing to validate and refine these targets, ensuring economic feasibility and resource-efficient exploration.
花岗质伟晶岩,特别是锂铯钽(LCT)类型,是稀有金属的重要来源,对现代技术至关重要,包括可持续性、能源储存和绿色能源应用。探索和定位LCT伟晶岩对于满足绿色技术对锂等关键金属日益增长的需求至关重要。矿产远景建模提供了一种系统的方法来识别这些矿床,特别是在伊朗西部地区,那里的Sanandaj-Sirjan带(SaSZ)是LCT伟晶岩的潜在宿主。本研究旨在模拟SaSZ LCT伟晶岩的前景,主要有三个目标:(1)构建一个矿产系统框架,定义控制LCT伟晶岩成因的关键过程及其可映射代理;(2)使用知识驱动的方法确定高优先级勘探目标;(3)解决有限数据可用性(认知)和多模型集成(系统)带来的不确定性,以提高勘探可靠性。为了实现这些目标,三种著名的基于知识的算法——模糊推理系统、连续模糊伽玛和几何平均——使用公开可用的地质勘探数据集来生成基于矿物系统方法的远景模型。随后使用多数投票(MV)集成技术将这些组合成最终的预测模型。采用置信指数(CI)来量化和减轻与多算法方法相关的不确定性,为未来的勘探划定低风险、高可信度的区域。结果表明,该区北部和南部有高找矿带(约占研究区面积的2%),特别是在阿尔万杂岩体附近,主要位于远离其主岩体和变质光环内。该研究强调了将矿产系统框架与地理空间建模相结合以优化勘探策略的有效性。未来的研究应优先获取高分辨率的地球物理和地球化学数据,并进行系统的地面真相调查,以验证和完善这些目标,确保经济可行性和资源效率。
{"title":"Mineral system modeling of Lithium-Cesium-Tantalum (LCT)-type pegmatites: Regional-scale exploration targeting and uncertainty analysis in the Sanandaj-Sirjan zone, Western Iran","authors":"Majid Keykhay-Hosseinpoor ,&nbsp;Alok Porwal ,&nbsp;R. Kalimuthu ,&nbsp;Shanta Panja","doi":"10.1016/j.gexplo.2025.107885","DOIUrl":"10.1016/j.gexplo.2025.107885","url":null,"abstract":"<div><div>Granitic pegmatites, particularly lithium‑cesium‑tantalum (LCT) types, are vital sources of rare metals crucial for modern technologies, including sustainability, energy storage, and green energy applications. Exploring and targeting LCT pegmatites are essential to meet the increasing demand for critical metals like lithium in green technologies. Mineral prospectivity modeling provides a systematic approach to identifying these deposits, especially in regions such as western Iran, where the Sanandaj-Sirjan Zone (SaSZ) is the potential host of LCT pegmatites. This study aims to model the prospectivity of LCT pegmatites in the SaSZ, with three primary objectives: (i) to construct a mineral systems framework that defines the critical processes controlling the genesis of LCT pegmatites and their mappable proxies, (ii) to identify high-priority exploration targets using knowledge-driven approaches, and (iii) address uncertainties stemming from limited data availability (epistemic) and from the integration of multiple models (systemic) to improve exploration reliability. To achieve these objectives, three well-known knowledge-based algorithms—fuzzy inference systems, continuous fuzzy gamma, and geometric average—were employed using publicly available geo-exploration datasets to generate prospectivity models based on the mineral systems approach. These were subsequently combined into a final predictive model using a majority voting (MV) ensemble technique. A confidence index (CI) was incorporated to quantify and mitigate uncertainties associated with the multi-algorithm approaches, delineating low-risk, high-confidence zones for future exploration. The results show high prospectivity zones (~2 % of the study area) in the northern and southern parts of the SaSZ, particularly near the Alvand complexes, predominantly located farther from their host plutons and within metamorphic aureoles. This study highlights the efficacy of integrating mineral systems frameworks with geospatial modeling to optimize exploration strategies. Future research should prioritize acquiring high-resolution geophysical and geochemical data and conducting systematic ground-truthing to validate and refine these targets, ensuring economic feasibility and resource-efficient exploration.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"279 ","pages":"Article 107885"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144896090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Ore-forming process and fluid development at Nanpo Au deposit, Luang Prabang-Loei Belt (NW Laos): Evidence from H-O-S-Pb isotopes and inclusions 老挝琅勃拉邦-洛伊带南坡金矿成矿过程与流体发育:来自H-O-S-Pb同位素和包裹体的证据
IF 3.3 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-12-01 Epub Date: 2025-08-20 DOI: 10.1016/j.gexplo.2025.107883
Wei Wang , Hui Li , Jie Gan , Fuhao Xiong , Yu Gan , Bin Wang , Junqing Mu , Huan Liu
The Luang Prabang-Loei tectonic belt, as a significant polymetallic metallogenic belt within the Southeast Asian Tethys tectonic domain, hosts numerous gold deposits. However, the current understanding of the genetic types and mineralization processes of these gold deposits remains insufficient, which restricts the advancement of regional metallogenic theories. This study focuses on the newly discovered large-scale Nanpo gold deposit in this metallogenic belt. By systematically conducting analyses of ore deposit geological characteristics, fluid inclusion testing, and H-O-S-Pb isotope analyses, it aims to reveal the sources of ore-forming materials, clarify the properties and evolutionary patterns of ore-forming fluids, and further elucidate the genetic mechanism and the process of mineralization of the deposit. The orebodies of the Nanpo gold deposit typically have lenticular, stratoid, and veined shapes, which are clearly controlled by ductile shear zones. The ores are mainly of two types: quartz vein type and altered rock type. Based on the interpenetrating relationship of veins and the symbiotic assembly of minerals, the metallogenic process of the Nanpo gold deposit can be divided into three stages: (I) quartz-sericite-gold-poor pyrite stage, (II) quartz-polymetallic sulphide stage, and (III) quartz-carbonate mineral stage. With the help of studies on fluid inclusion petrography, microscopic thermometry and laser Raman spectroscopy, it can be found that there are three main types of fluid inclusions in the deposit, namely, NaCl-H2O, NaCl-CO2-H2O and pure CO2. In general terms, they are part of a NaCl - H2O - CO2 ± CH4 ± N2 low-temperature to intermediate-temperature/low-salinity fluid system. Using the isotopes S-Pb can be seen, the ore - forming materials come to a large extent from the homogenized lower crust - upper mantle. The H - O isotopes suggest that the ore - forming fluids were of metamorphic water which had an affinity to meteoric waters in the later stage. These evidences suggest that the Nanpo gold deposit is a typical orogenic gold deposit, and its formation is closely associated with the collisional orogeny in Indo - China block after the Paleo — Tethys closed. This study provides a theoretical foundation for the advancement of regional metallogenic theories and offers guidance for regional mineral exploration.
Luang Prabang-Loei构造带是东南亚特提斯构造域中重要的多金属成矿带,拥有大量金矿床。然而,目前对这些金矿床的成因类型和成矿过程认识不足,制约了区域成矿理论的发展。本文以该成矿带新发现的大型南坡金矿床为研究对象。系统开展矿床地质特征分析、流体包裹体测试、H-O-S-Pb同位素分析,揭示成矿物质来源,明确成矿流体性质及演化模式,进一步阐明矿床的成因机制和成矿作用过程。南坡金矿床矿体具有典型的透镜状、层状和脉状矿体,明显受韧性剪切带控制。矿石主要为石英脉型和蚀变岩型两种类型。根据矿脉互穿关系和矿物共生组合,将南坡金矿床成矿过程划分为3个阶段:(1)石英—绢云母—贫金黄铁矿阶段、(2)石英—多金属硫化物阶段和(3)石英—碳酸盐矿物阶段。通过流体包裹体岩石学、显微测温和激光拉曼光谱研究发现,矿床中流体包裹体主要有3种类型,分别为NaCl-H2O、NaCl-CO2-H2O和纯CO2。一般来说,它们是NaCl - H2O - CO2±CH4±N2低温到中温/低盐度流体体系的一部分。利用S-Pb同位素可以看出,成矿物质在很大程度上来自均质化的下地壳-上地幔。氢氧同位素表明成矿流体为变质水,后期与大气水有亲缘关系。这些证据表明,南坡金矿床是典型的造山带型金矿床,其形成与古特提斯闭合后印支地块的碰撞造山作用密切相关。该研究为区域成矿理论的发展提供了理论基础,对区域矿产勘查具有指导意义。
{"title":"Ore-forming process and fluid development at Nanpo Au deposit, Luang Prabang-Loei Belt (NW Laos): Evidence from H-O-S-Pb isotopes and inclusions","authors":"Wei Wang ,&nbsp;Hui Li ,&nbsp;Jie Gan ,&nbsp;Fuhao Xiong ,&nbsp;Yu Gan ,&nbsp;Bin Wang ,&nbsp;Junqing Mu ,&nbsp;Huan Liu","doi":"10.1016/j.gexplo.2025.107883","DOIUrl":"10.1016/j.gexplo.2025.107883","url":null,"abstract":"<div><div>The Luang Prabang-Loei tectonic belt, as a significant polymetallic metallogenic belt within the Southeast Asian Tethys tectonic domain, hosts numerous gold deposits. However, the current understanding of the genetic types and mineralization processes of these gold deposits remains insufficient, which restricts the advancement of regional metallogenic theories. This study focuses on the newly discovered large-scale Nanpo gold deposit in this metallogenic belt. By systematically conducting analyses of ore deposit geological characteristics, fluid inclusion testing, and H-O-S-Pb isotope analyses, it aims to reveal the sources of ore-forming materials, clarify the properties and evolutionary patterns of ore-forming fluids, and further elucidate the genetic mechanism and the process of mineralization of the deposit. The orebodies of the Nanpo gold deposit typically have lenticular, stratoid, and veined shapes, which are clearly controlled by ductile shear zones. The ores are mainly of two types: quartz vein type and altered rock type. Based on the interpenetrating relationship of veins and the symbiotic assembly of minerals, the metallogenic process of the Nanpo gold deposit can be divided into three stages: (I) quartz-sericite-gold-poor pyrite stage, (II) quartz-polymetallic sulphide stage, and (III) quartz-carbonate mineral stage. With the help of studies on fluid inclusion petrography, microscopic thermometry and laser Raman spectroscopy, it can be found that there are three main types of fluid inclusions in the deposit, namely, NaCl-H<sub>2</sub>O, NaCl-CO<sub>2</sub>-H<sub>2</sub>O and pure CO<sub>2</sub>. In general terms, they are part of a NaCl - H<sub>2</sub>O - CO<sub>2</sub> ± CH<sub>4</sub> ± N<sub>2</sub> low-temperature to intermediate-temperature/low-salinity fluid system. Using the isotopes S-Pb can be seen, the ore - forming materials come to a large extent from the homogenized lower crust - upper mantle. The H - O isotopes suggest that the ore - forming fluids were of metamorphic water which had an affinity to meteoric waters in the later stage. These evidences suggest that the Nanpo gold deposit is a typical orogenic gold deposit, and its formation is closely associated with the collisional orogeny in Indo - China block after the Paleo — Tethys closed. This study provides a theoretical foundation for the advancement of regional metallogenic theories and offers guidance for regional mineral exploration.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"279 ","pages":"Article 107883"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144907090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Airborne hyperspectral mapping and shortwave infrared spectroscopy of white mica from the Baiyanghe uranium district, Northwest China, with applications in exploration 白洋河铀矿区白云母航空高光谱成图与短波红外光谱分析及其勘探应用
IF 3.3 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-12-01 Epub Date: 2025-08-19 DOI: 10.1016/j.gexplo.2025.107881
Qingjun Xu , Zhixin Zhang , Jing Wang , Ruiwei Li , Chuan Zhang , Yilong Wang , Ding Wu , Fawang Ye
Airborne hyperspectral and shortwave infrared (SWIR) spectroscopy technology has significant advantages and application prospects in the fine identification and mapping of alteration minerals. The white mica spectra contain rich geological information, including the hydrothermal environment in which white mica formed and its relationship with mineralization. How variations in the chemical components, temperature, and pH of hydrothermal fluid constrain the Al–OH wavelengths of white mica in meso-epithermal deposits is still debated. Moreover, the relationships between uranium mineralization and the spectral parameters of white mica in hydrothermal uranium deposits are poorly understood. In this study, we present shortwave infrared airborne spectral imager (SASI) hyperspectral data, SWIR FieldSpec4 hyperspectral data, petrography data, and geochemical data, including those from X-ray diffraction (XRD), electron probe microanalysis (EPMA), and hydrogen and oxygen isotopes, for white mica from the Baiyanghe uranium district. The SASI airborne hyperspectral alteration mineral mapping shows that the distribution of white mica exhibits distinct zoning characteristics. The SWIR and XRD analyses indicate that the alteration minerals are mainly quartz, chlorite, and illite, with Al–OH absorption wavelengths ranging from 2190 nm to 2220 nm. The geochemical compositions indicate an obvious Tschermak substitution in white mica and suggest that variations in the Al–OH wavelengths of white mica are affected mainly by the Fe and Mg contents and Fe/(Fe + Mg) ratios in addition to the wall rock composition and hydrothermal fluid. The presence of Al-rich (Si-poor) white mica with a shorter Al–OH wavelength at approximately 2200 nm indicates a relatively high-temperature and acidic hydrothermal environment. In contrast, the presence of Al-poor (Si-rich) white mica with a longer Al–OH wavelength at approximately 2200 nm suggests a relatively low-temperature and neutral hydrothermal environment. In addition, white micas close to uranium mineralization in the northern contact zone between the Yangzhuang granite porphyry and the Devonian intermediate–acid volcanic rocks of the Baiyanghe uranium district have shorter Al–OH wavelengths, greater illite spectral maturity index (ISM) values, and lower full width at half maximum at approximately 2200 nm (FWHM2200) values than those not associated with uranium mineralization. The spatial distributions and variations in the Al–OH wavelengths, ISM values, and FWHM2200 values for white mica suggest that a hydrothermal mineralization center may be located in the northern contact zone, indicating that white mica can be used as an important indicator of alteration minerals for uranium exploration in the Xuemisitan uranium metallogenic belt or other hydrothermal deposits.
航空高光谱与短波红外(SWIR)光谱技术在蚀变矿物精细识别与填图中具有显著的优势和应用前景。白云母光谱包含丰富的地质信息,包括白云母形成的热液环境及其与成矿作用的关系。热液流体的化学成分、温度和pH值的变化如何限制中低温热液矿床中白色云母的Al-OH波长仍然存在争议。此外,热液铀矿床中白色云母光谱参数与铀矿化的关系尚不清楚。利用短波红外机载光谱成像仪(SASI)高光谱、SWIR FieldSpec4高光谱、岩石学、x射线衍射(XRD)、电子探针微量分析(EPMA)、氢、氧同位素等地球化学数据对白洋河铀矿区的白色云母进行了研究。SASI航空高光谱蚀变矿物填图显示,白云母的分布具有明显的分带特征。SWIR和XRD分析表明,蚀变矿物主要为石英、绿泥石和伊利石,Al-OH吸收波长在2190 ~ 2220 nm之间。白云母的地球化学组成显示出明显的Tschermak取代,表明白云母的Al-OH波长变化主要受Fe、Mg含量和Fe/(Fe + Mg)比值的影响,此外还受围岩组成和热液的影响。富al(贫si)白云母的存在,其Al-OH波长较短,约为2200 nm,表明其存在相对高温的酸性热液环境。相比之下,贫铝(富硅)白云母的存在,其Al-OH波长较长,约为2200 nm,表明存在相对低温和中性的热液环境。此外,白洋河铀矿区阳庄花岗斑岩与泥盆系中酸性火山岩北部接触带靠近铀矿化的白色云母Al-OH波长较短,伊丽石光谱成熟度指数(ISM)值较大,在约2200 nm处半最大值全宽(FWHM2200)值较低。白云母Al-OH波长、ISM值和FWHM2200值的空间分布和变化表明,北接触带可能存在热液成矿中心,表明白云母可作为雪米斯滩铀成矿带或其他热液矿床蚀变矿物的重要指示物。
{"title":"Airborne hyperspectral mapping and shortwave infrared spectroscopy of white mica from the Baiyanghe uranium district, Northwest China, with applications in exploration","authors":"Qingjun Xu ,&nbsp;Zhixin Zhang ,&nbsp;Jing Wang ,&nbsp;Ruiwei Li ,&nbsp;Chuan Zhang ,&nbsp;Yilong Wang ,&nbsp;Ding Wu ,&nbsp;Fawang Ye","doi":"10.1016/j.gexplo.2025.107881","DOIUrl":"10.1016/j.gexplo.2025.107881","url":null,"abstract":"<div><div>Airborne hyperspectral and shortwave infrared (SWIR) spectroscopy technology has significant advantages and application prospects in the fine identification and mapping of alteration minerals. The white mica spectra contain rich geological information, including the hydrothermal environment in which white mica formed and its relationship with mineralization. How variations in the chemical components, temperature, and pH of hydrothermal fluid constrain the Al–OH wavelengths of white mica in meso-epithermal deposits is still debated. Moreover, the relationships between uranium mineralization and the spectral parameters of white mica in hydrothermal uranium deposits are poorly understood. In this study, we present shortwave infrared airborne spectral imager (SASI) hyperspectral data, SWIR FieldSpec4 hyperspectral data, petrography data, and geochemical data, including those from X-ray diffraction (XRD), electron probe microanalysis (EPMA), and hydrogen and oxygen isotopes, for white mica from the Baiyanghe uranium district. The SASI airborne hyperspectral alteration mineral mapping shows that the distribution of white mica exhibits distinct zoning characteristics. The SWIR and XRD analyses indicate that the alteration minerals are mainly quartz, chlorite, and illite, with Al–OH absorption wavelengths ranging from 2190 nm to 2220 nm. The geochemical compositions indicate an obvious Tschermak substitution in white mica and suggest that variations in the Al–OH wavelengths of white mica are affected mainly by the Fe and Mg contents and Fe/(Fe + Mg) ratios in addition to the wall rock composition and hydrothermal fluid. The presence of Al-rich (Si-poor) white mica with a shorter Al–OH wavelength at approximately 2200 nm indicates a relatively high-temperature and acidic hydrothermal environment. In contrast, the presence of Al-poor (Si-rich) white mica with a longer Al–OH wavelength at approximately 2200 nm suggests a relatively low-temperature and neutral hydrothermal environment. In addition, white micas close to uranium mineralization in the northern contact zone between the Yangzhuang granite porphyry and the Devonian intermediate–acid volcanic rocks of the Baiyanghe uranium district have shorter Al–OH wavelengths, greater illite spectral maturity index (ISM) values, and lower full width at half maximum at approximately 2200 nm (FWHM2200) values than those not associated with uranium mineralization. The spatial distributions and variations in the Al–OH wavelengths, ISM values, and FWHM2200 values for white mica suggest that a hydrothermal mineralization center may be located in the northern contact zone, indicating that white mica can be used as an important indicator of alteration minerals for uranium exploration in the Xuemisitan uranium metallogenic belt or other hydrothermal deposits.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"279 ","pages":"Article 107881"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144896089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Improving spatial interpolation for anomaly analysis in presence of sparse, clustered or imprecise data sets 改进空间插值的异常分析存在稀疏,聚类或不精确的数据集
IF 3.3 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-12-01 Epub Date: 2025-07-21 DOI: 10.1016/j.gexplo.2025.107868
Stéphane Belbèze , Jérémy Rohmer , Dominique Guyonnet , Philippe Négrel , Timo Tarvainen
In this study, we present a new method of interpolation and anomaly detection especially designed for sparse, clustered or imprecise environmental data (SIC). Such data cannot be processed by current state of the art spatial methods and models, including the most widely used, such as kriging. Indeed, the statistics obtained on SIC data (on the order of 5–30) do not allow us to define a covariance or to calibrate the numerous hyper-parameters of sophisticated Bayesian or deep image prior models. We therefore adapted an information dissemination algorithm to handle SIC data. This probabilistic model has been enriched (anisotropy, de-clustering, auto-variography, multi-support, treatment of covariates, and censored data) in a way that fully meets the needs for environmental SIC data and can be used in conjunction with hybrid propagation of epistemic and aleatoric uncertainties and anomaly detection, whatever their mathematical form. The new interpolator for anomaly detection was applied on a very small set of 13 sparse data points characteristic of small-scale environmental studies, on digital-challenge datasets and on two real datasets, i.e., a large-scale geochemical dataset and a SIC urban soil dataset. Results highlight the added value of the proposed algorithm, that is able to pinpoint anomalies in SIC data, while avoiding in particular the smoothing effects of certain previous methods.
在本研究中,我们提出了一种专门针对稀疏、聚类或不精确环境数据(SIC)的插值和异常检测新方法。目前最先进的空间方法和模型无法处理这些数据,包括最广泛使用的空间方法和模型,如克里格。事实上,在SIC数据上获得的统计数据(在5-30的数量级上)不允许我们定义协方差或校准复杂贝叶斯或深度图像先验模型的众多超参数。因此,我们采用了一种信息传播算法来处理SIC数据。这种概率模型已经被丰富(各向异性、去聚类、自动变异、多支持、协变量处理和审查数据),以一种完全满足环境SIC数据需求的方式,可以与认知和任意不确定性的混合传播以及异常检测结合使用,无论其数学形式如何。本文将新的异常检测插值器应用于小尺度环境研究的13个稀疏数据点、数字挑战数据集和两个真实数据集,即大尺度地球化学数据集和SIC城市土壤数据集。结果突出了所提出算法的附加价值,即能够精确定位SIC数据中的异常,同时特别避免了某些先前方法的平滑效果。
{"title":"Improving spatial interpolation for anomaly analysis in presence of sparse, clustered or imprecise data sets","authors":"Stéphane Belbèze ,&nbsp;Jérémy Rohmer ,&nbsp;Dominique Guyonnet ,&nbsp;Philippe Négrel ,&nbsp;Timo Tarvainen","doi":"10.1016/j.gexplo.2025.107868","DOIUrl":"10.1016/j.gexplo.2025.107868","url":null,"abstract":"<div><div>In this study, we present a new method of interpolation and anomaly detection especially designed for sparse, clustered or imprecise environmental data (SIC). Such data cannot be processed by current state of the art spatial methods and models, including the most widely used, such as kriging. Indeed, the statistics obtained on SIC data (on the order of 5–30) do not allow us to define a covariance or to calibrate the numerous hyper-parameters of sophisticated Bayesian or deep image prior models. We therefore adapted an information dissemination algorithm to handle SIC data. This probabilistic model has been enriched (anisotropy, de-clustering, auto-variography, multi-support, treatment of covariates, and censored data) in a way that fully meets the needs for environmental SIC data and can be used in conjunction with hybrid propagation of epistemic and aleatoric uncertainties and anomaly detection, whatever their mathematical form. The new interpolator for anomaly detection was applied on a very small set of 13 sparse data points characteristic of small-scale environmental studies, on digital-challenge datasets and on two real datasets, i.e., a large-scale geochemical dataset and a SIC urban soil dataset. Results highlight the added value of the proposed algorithm, that is able to pinpoint anomalies in SIC data, while avoiding in particular the smoothing effects of certain previous methods.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"279 ","pages":"Article 107868"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144829533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The lithium mineralization potential of Pan-African pegmatites in Mozambique 莫桑比克泛非伟晶岩的锂成矿潜力
IF 3.3 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-12-01 Epub Date: 2025-08-19 DOI: 10.1016/j.gexplo.2025.107882
Violeta Lavínia Bunzula , Axel Müller , Muriel Erambert , Valby van Schijndel , Bernhard Schulz , Jens Götze , Sabine Gilbricht , Jiří Sláma , Siri Simonsen
The Pan-African rare-element pegmatites of the Alto Ligonha Pegmatite District in northern Mozambique contain abundant Li-rich micas and primary Li aluminosilicates, such as spodumene. Given the rising global demand for Li in the manufacture of Li-ion batteries, these pegmatites are viewed as potential hard rock sources of Li. In this study, five pegmatites from the Alto Ligonha region were investigated to gain a better understanding of the fractionation processes of pegmatite melts that lead to Li enrichment and to assess the economic potential of the Li mineralization. Mica, quartz, and spodumene collected from various zones within these pegmatites were analyzed. Contents of Li, Rb, Cs, Ta, and Tl in mica and of Li and Al in quartz reveal a very strong internal fractionation of the pegmatite melt with progressing crystallization. Li2O contents in micas increase from 0.1 to 1.4 wt% in the wall zones, to 0.3–1.7 wt% in the intermediate zones, to 1.5–3.8 wt% in the core zones and up to 5.4 wt% in the core zone pockets. Using known mica/melt Li partition coefficients, the Li contents of the melt at the initial crystallization stage was calculated to be between 315 and 3910 ppm for the Li-rich pegmatites. The Li saturation of about 5000 ppm in respect to spodumene crystallization was exceeded for most pegmatites at the final core-zone crystallization. The theoretical calculations confirm field observations that spodumene occurs in pegmatite core zones only. The analyzed spodumene show low and variable bulk Li2O contents between 1.2 and 3.0 wt%. The low Li contents in spodumene are mainly the result of kaolinization due to tropical weathering. The final deposition of the released Li, however, could not be identified. Inferred resource calculations revealed that the investigated pegmatites contain low Li2O tonnages. However, spodumene as well as Li-rich mica might be mined selectively as a by-product of gemstone and columbite-tantalite mining.
莫桑比克北部Alto Ligonha伟晶岩区泛非稀有元素伟晶岩含有丰富的富锂云母和原生锂铝硅酸盐,如锂辉石。鉴于锂离子电池制造对锂的全球需求不断上升,这些伟晶岩被视为锂的潜在硬岩来源。本文对上利贡尼亚地区的5种伟晶岩进行了研究,以更好地了解导致Li富集的伟晶岩熔体分选过程,并评估Li矿化的经济潜力。分析了从这些伟晶岩的不同区域收集的云母、石英和锂辉石。云母中Li、Rb、Cs、Ta、Tl含量和石英中Li、Al含量显示出极强的晶化过程。云母中Li2O含量在岩壁区增加0.1 ~ 1.4 wt%,在中间区增加0.3 ~ 1.7 wt%,在核心区增加1.5 ~ 3.8 wt%,在核心区袋状区增加5.4 wt%。利用已知的云母/熔体Li分配系数,计算出富锂伟晶岩熔体在初始结晶阶段的Li含量在315 ~ 3910 ppm之间。大部分伟晶岩在岩心区最终结晶时,锂辉石结晶的锂饱和度超过了5000 ppm左右。理论计算证实了锂辉石只存在于伟晶岩核心区的野外观测结果。所分析的锂辉石Li2O含量低且多变,在1.2 ~ 3.0 wt%之间。锂辉石中Li含量低主要是热带风化作用导致高岭土化的结果。然而,李获释后的最终证词无法确定。推断资源计算表明,所调查的伟晶岩含有低Li2O吨数。然而,锂辉石和富锂云母可以作为宝石和铌钽矿开采的副产物选择性开采。
{"title":"The lithium mineralization potential of Pan-African pegmatites in Mozambique","authors":"Violeta Lavínia Bunzula ,&nbsp;Axel Müller ,&nbsp;Muriel Erambert ,&nbsp;Valby van Schijndel ,&nbsp;Bernhard Schulz ,&nbsp;Jens Götze ,&nbsp;Sabine Gilbricht ,&nbsp;Jiří Sláma ,&nbsp;Siri Simonsen","doi":"10.1016/j.gexplo.2025.107882","DOIUrl":"10.1016/j.gexplo.2025.107882","url":null,"abstract":"<div><div>The Pan-African rare-element pegmatites of the Alto Ligonha Pegmatite District in northern Mozambique contain abundant Li-rich micas and primary Li aluminosilicates, such as spodumene. Given the rising global demand for Li in the manufacture of Li-ion batteries, these pegmatites are viewed as potential hard rock sources of Li. In this study, five pegmatites from the Alto Ligonha region were investigated to gain a better understanding of the fractionation processes of pegmatite melts that lead to Li enrichment and to assess the economic potential of the Li mineralization. Mica, quartz, and spodumene collected from various zones within these pegmatites were analyzed. Contents of Li, Rb, Cs, Ta, and Tl in mica and of Li and Al in quartz reveal a very strong internal fractionation of the pegmatite melt with progressing crystallization. Li<sub>2</sub>O contents in micas increase from 0.1 to 1.4 wt% in the wall zones, to 0.3–1.7 wt% in the intermediate zones, to 1.5–3.8 wt% in the core zones and up to 5.4 wt% in the core zone pockets. Using known mica/melt Li partition coefficients, the Li contents of the melt at the initial crystallization stage was calculated to be between 315 and 3910 ppm for the Li-rich pegmatites. The Li saturation of about 5000 ppm in respect to spodumene crystallization was exceeded for most pegmatites at the final core-zone crystallization. The theoretical calculations confirm field observations that spodumene occurs in pegmatite core zones only. The analyzed spodumene show low and variable bulk Li<sub>2</sub>O contents between 1.2 and 3.0 wt%. The low Li contents in spodumene are mainly the result of kaolinization due to tropical weathering. The final deposition of the released Li, however, could not be identified. Inferred resource calculations revealed that the investigated pegmatites contain low Li<sub>2</sub>O tonnages. However, spodumene as well as Li-rich mica might be mined selectively as a by-product of gemstone and columbite-tantalite mining.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"279 ","pages":"Article 107882"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144913743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Genesis and magmatic-hydrothermal evolution of the Silurian Pingtan W deposit, Nanling Range, South China: Constraints from scheelite and apatite geochemistry and geochronology 南岭志留系平潭钨矿成因及岩浆-热液演化:来自白钨矿和磷灰石地球化学及年代学的制约
IF 3.3 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-12-01 Epub Date: 2025-08-20 DOI: 10.1016/j.gexplo.2025.107884
Hongfei Di , Yong-Jun Shao , David Chew , Jian-Feng Chen , Wen-Jie Fang , Yi-Qu Xiong
A cluster of Silurian W mineralization events have been reported in South China but the ore-forming processes remain not well-constrained, impeding a comprehensive understanding of deposit genesis and hindering the deployment of further exploration programs. In this study, we examine the newly discovered Silurian Pingtan W deposit as a case study. We undertook a comprehensive study of microtextures and geochemistry on scheelite and apatite, and U–Pb geochronology on apatite to determine the timing of W mineralization as well as the origin and evolution of the ore-forming fluids. Based on BSE and CL images, we identify two types of scheelite (Sch) and apatite (Ap): Sch A (A1 and A2) and Ap I in the altered granite-scheelite stage, and Sch B (B1 and B2) and Ap II in the quartz-scheelite stage. The Mo contents and Eu/Eu* ratios of multi-stage scheelite suggest a decrease in fluid fO2 from the early to late stages within each mineralization phase. The Eu/Eu* ratios of multi-stage apatite indicate an increase in fluid fO2 from the altered granite-scheelite stage to the quartz-scheelite stage. The Y/Ho ratios of these phases of apatite and scheelite growth imply that the initial fluids originated from the host porphyritic biotite monzogranite, and early-stage apatite crystallization led to the depletion of Y and Ho in scheelite. A support vector machine biplot shows that Ap I is magmatic in origin, while Ap II is hydrothermal in origin. The hydrothermal Ap II yields a U–Pb age of 433.7 ± 9.7 Ma (2σ, MSWD = 1.9), aligning with the emplacement ages (431–430 Ma) of the porphyritic biotite monzogranite. These data imply that the Pingtan W deposit represents a typical altered-granite type W deposit genetically linked to its host Silurian porphyritic biotite monzogranite. In addition, the estimated F and Cl contents in melt and fluid based on their contents in apatite indicate that the volatile-rich altered porphyritic biotite monzogranite has great W mineralization potential. Considering previous studies on the Silurian W mineralization, we propose that the Silurian may represent another significant period for W mineralization in South China, with contemporaneous highly evolved and volatile-rich granites serving as a new exploration target for W deposits.
华南地区已报道了一系列志留系W型成矿事件,但成矿过程仍未得到很好的约束,这阻碍了对矿床成因的全面认识,并阻碍了进一步勘探计划的部署。本文以新发现的志留系平潭钨矿为例进行了研究。对白钨矿和磷灰石进行了显微结构和地球化学综合研究,对磷灰石进行了U-Pb年代学研究,确定了钨的成矿时间、成矿流体的起源和演化。根据BSE和CL图像,确定了白钨矿(Sch)和磷灰石(Ap)两种类型:蚀变花岗岩白钨矿阶段的Sch A (A1和A2)和Ap I,以及石英白钨矿阶段的Sch B (B1和B2)和Ap II。多期白钨矿Mo含量和Eu/Eu*比值表明,各成矿期流体fO2由早到晚呈递减趋势。多期磷灰石Eu/Eu*比值表明,从蚀变花岗白钨矿期到石英白钨矿期,流体fO2增加。磷灰石和白钨矿生长各阶段的Y/Ho比值表明,初始流体来源于寄主斑岩型黑云母二长花岗岩,磷灰石早期结晶导致白钨矿中Y和Ho的耗蚀。支持向量机双标图显示,Apⅰ为岩浆成因,Apⅱ为热液成因。热液Apⅱ的U-Pb年龄为433.7±9.7 Ma (2σ, MSWD = 1.9),与斑岩型黑云母二长花岗岩的侵位年龄(431 ~ 430 Ma)一致。这些资料表明,平潭钨矿床是一个典型的蚀变花岗岩型钨矿床,其成因与寄主志留系斑岩型黑云母二长花岗岩有关。此外,根据磷灰石中F和Cl的含量估算熔体和流体中F和Cl的含量,表明富挥发性蚀变斑岩黑云母二长花岗岩具有较大的W成矿潜力。结合前人对志留系钨成矿作用的研究,我们认为志留系可能是华南钨成矿的另一个重要时期,同时期高演化、富挥发物质的花岗岩可能是钨矿床新的找矿目标。
{"title":"Genesis and magmatic-hydrothermal evolution of the Silurian Pingtan W deposit, Nanling Range, South China: Constraints from scheelite and apatite geochemistry and geochronology","authors":"Hongfei Di ,&nbsp;Yong-Jun Shao ,&nbsp;David Chew ,&nbsp;Jian-Feng Chen ,&nbsp;Wen-Jie Fang ,&nbsp;Yi-Qu Xiong","doi":"10.1016/j.gexplo.2025.107884","DOIUrl":"10.1016/j.gexplo.2025.107884","url":null,"abstract":"<div><div>A cluster of Silurian W mineralization events have been reported in South China but the ore-forming processes remain not well-constrained, impeding a comprehensive understanding of deposit genesis and hindering the deployment of further exploration programs. In this study, we examine the newly discovered Silurian Pingtan W deposit as a case study. We undertook a comprehensive study of microtextures and geochemistry on scheelite and apatite, and U–Pb geochronology on apatite to determine the timing of W mineralization as well as the origin and evolution of the ore-forming fluids. Based on BSE and CL images, we identify two types of scheelite (Sch) and apatite (Ap): Sch A (A1 and A2) and Ap I in the altered granite-scheelite stage, and Sch B (B1 and B2) and Ap II in the quartz-scheelite stage. The Mo contents and Eu/Eu* ratios of multi-stage scheelite suggest a decrease in fluid <em>f</em>O<sub>2</sub> from the early to late stages within each mineralization phase. The Eu/Eu* ratios of multi-stage apatite indicate an increase in fluid <em>f</em>O<sub>2</sub> from the altered granite-scheelite stage to the quartz-scheelite stage. The Y/Ho ratios of these phases of apatite and scheelite growth imply that the initial fluids originated from the host porphyritic biotite monzogranite, and early-stage apatite crystallization led to the depletion of Y and Ho in scheelite. A support vector machine biplot shows that Ap I is magmatic in origin, while Ap II is hydrothermal in origin. The hydrothermal Ap II yields a U–Pb age of 433.7 ± 9.7 Ma (2σ, MSWD = 1.9), aligning with the emplacement ages (431–430 Ma) of the porphyritic biotite monzogranite. These data imply that the Pingtan W deposit represents a typical altered-granite type W deposit genetically linked to its host Silurian porphyritic biotite monzogranite. In addition, the estimated F and Cl contents in melt and fluid based on their contents in apatite indicate that the volatile-rich altered porphyritic biotite monzogranite has great W mineralization potential. Considering previous studies on the Silurian W mineralization, we propose that the Silurian may represent another significant period for W mineralization in South China, with contemporaneous highly evolved and volatile-rich granites serving as a new exploration target for W deposits.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"279 ","pages":"Article 107884"},"PeriodicalIF":3.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144893909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Heavy metals' release behavior in antimony tailings dump and its response to different rainfall conditions 锑尾矿库重金属释放行为及其对不同降雨条件的响应
IF 3.4 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-11-01 Epub Date: 2025-06-16 DOI: 10.1016/j.gexplo.2025.107846
Weixiao Chen , Pu Liu , Zhimin Xu , Ying Luo , Yingdan Zhang , Yidan Wang
Under the influence of natural rainfall, heavy metals (HMs) in Qinglong antimony tailings are easily released into surface or underground runoff, posing a great threat to the ecological environment and human health. In this study, an independently designed rainfall simulation device was used to study the effects of tailings leachate and carbonate rocks on the release behavior and mechanism of HMs under rainfall activities (different rainfall intensities and intermittent rainfall). X-ray diffraction shows that the characteristic minerals of tailings are quartz, gypsum, kaolinite, pyrite, fluorite and calcite, and the main antimony mineral is stibnite. The simulated rainfall shows that lower intensities result in decreased pH, increased EC, higher heavy metal concentrations, and cumulative release amounts positively correlated with rainfall intensity, but has little effect on the leaching mechanism of HMs. The release of Sb is mainly a diffusion mechanism, and the leaching of As, Fe, and Mn is mainly controlled by surface leaching. Intermittent rainfall leaching significantly promoted the release of Sb and As, changing the release control mechanism and increasing concentrations by 109.2 μg/L and 16.6 μg/L, respectively. Carbonate rocks can effectively inhibit release of HMs from tailings while elevating Sb/As/Fe valence states and inducing Sb-As-Fe-Mn release correlations. The kinetic release mathematical model reflects that the release process of HMs is controlled by multiple factors. This work has deepened the understanding of heavy metal leaching under various rainfall conditions and provided a useful reference for managing open-pit tailings in karst mountainous areas.
在自然降雨的影响下,青龙锑尾矿中的重金属极易进入地表或地下径流,对生态环境和人体健康构成极大威胁。本研究采用自主设计的降雨模拟装置,研究了降雨活动(不同降雨强度和间歇降雨)下尾矿渗滤液和碳酸盐岩对HMs释放行为和机制的影响。x射线衍射结果表明,尾矿的特征矿物为石英、石膏、高岭石、黄铁矿、萤石和方解石,锑矿物主要为辉锑矿。模拟降雨结果表明,较低强度导致土壤pH降低、EC升高、重金属浓度升高,累积释放量与降雨强度呈正相关,但对土壤有机质的淋溶机制影响不大。Sb的释放以扩散机制为主,As、Fe、Mn的浸出主要受表面浸出控制。间歇性降雨淋溶显著促进了Sb和As的释放,改变了释放控制机制,浓度分别增加了109.2 μg/L和16.6 μg/L。碳酸盐岩可以有效抑制尾矿中HMs的释放,同时提高Sb/As/Fe价态,诱导Sb-As-Fe- mn释放相关性。动力学释放数学模型反映了HMs的释放过程受多种因素控制。该工作加深了对不同降雨条件下重金属浸出的认识,为岩溶山区露天尾矿管理提供了有益的参考。
{"title":"Heavy metals' release behavior in antimony tailings dump and its response to different rainfall conditions","authors":"Weixiao Chen ,&nbsp;Pu Liu ,&nbsp;Zhimin Xu ,&nbsp;Ying Luo ,&nbsp;Yingdan Zhang ,&nbsp;Yidan Wang","doi":"10.1016/j.gexplo.2025.107846","DOIUrl":"10.1016/j.gexplo.2025.107846","url":null,"abstract":"<div><div>Under the influence of natural rainfall, heavy metals (HMs) in Qinglong antimony tailings are easily released into surface or underground runoff, posing a great threat to the ecological environment and human health. In this study, an independently designed rainfall simulation device was used to study the effects of tailings leachate and carbonate rocks on the release behavior and mechanism of HMs under rainfall activities (different rainfall intensities and intermittent rainfall). X-ray diffraction shows that the characteristic minerals of tailings are quartz, gypsum, kaolinite, pyrite, fluorite and calcite, and the main antimony mineral is stibnite. The simulated rainfall shows that lower intensities result in decreased pH, increased EC, higher heavy metal concentrations, and cumulative release amounts positively correlated with rainfall intensity, but has little effect on the leaching mechanism of HMs. The release of Sb is mainly a diffusion mechanism, and the leaching of As, Fe, and Mn is mainly controlled by surface leaching. Intermittent rainfall leaching significantly promoted the release of Sb and As, changing the release control mechanism and increasing concentrations by 109.2 μg/L and 16.6 μg/L, respectively. Carbonate rocks can effectively inhibit release of HMs from tailings while elevating Sb/As/Fe valence states and inducing Sb-As-Fe-Mn release correlations. The kinetic release mathematical model reflects that the release process of HMs is controlled by multiple factors. This work has deepened the understanding of heavy metal leaching under various rainfall conditions and provided a useful reference for managing open-pit tailings in karst mountainous areas.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"278 ","pages":"Article 107846"},"PeriodicalIF":3.4,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Drinking water quality in the Malaysian indigenous community of Pos Kemar (Perak): Pollution, risks, and household practices 马来西亚波基玛尔(霹雳州)土著社区的饮用水质量:污染、风险和家庭习惯
IF 3.4 2区 地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2025-11-01 Epub Date: 2025-06-21 DOI: 10.1016/j.gexplo.2025.107849
Sarva Mangala Praveena , Nurul Shafiqah Sukri , Aini Saadah Mohd Soad , Samuel Abiodun Kehinde
Access to clean water continues to be a major obstacle for indigenous communities in remote areas. The objective of this study is to evaluate the extent of pollution in the drinking water of the indigenous tribe community of Pos Kemar (Malaysia), specifically examining the issue of microbiological contamination and the resulting health hazards. Drinking water samples were collected from 108 households and analysed for physicochemical parameters, heavy metals, and microbial contamination, particularly Escherichia coli (E. coli). In addition, a questionnaire study was carried out to investigate behaviour related to water handling, hygiene, and reported health complaints. The results indicated that although the majority of physicochemical and heavy metal levels were within the Malaysian Drinking Water Quality Standards, the presence of microbiological contamination, namely E. coli, greatly beyond the safely acceptable thresholds in all samples. According to a simplified Quantitative Microbial Risk Assessment, all samples exceeded the World Health Organization health-based target for pathogenic E. coli, indicating a significant health risk from E. coli infection. The study further revealed that effective water treatment, such as boiling, substantially decreased levels of pollution. Nevertheless, deficiencies in water management protocols and sanitation were identified, which greatly contributed to the high occurrence of waterborne illnesses. Specifically, 31 % of the population reported experiencing health symptoms related to inadequate water quality, such as diarrhea and skin infections. The results emphasize the immediate requirement for enhanced water treatment measures and public health approaches to reduce the hazards of waterborne illnesses in indigenous populations.
获得清洁水仍然是偏远地区土著社区面临的主要障碍。这项研究的目的是评估Pos Kemar(马来西亚)土著部落社区饮用水中的污染程度,具体审查微生物污染问题及其造成的健康危害。从108个家庭收集了饮用水样本,并分析了理化参数、重金属和微生物污染,特别是大肠杆菌。此外,还进行了一项问卷调查,以调查与水处理、卫生和报告的健康投诉有关的行为。结果表明,虽然大部分物化和重金属含量都在马来西亚饮用水质量标准之内,但所有样品中存在的微生物污染,即大肠杆菌,大大超出了安全可接受的阈值。根据简化的定量微生物风险评估,所有样本均超过世界卫生组织致病性大肠杆菌的健康指标,表明大肠杆菌感染存在重大健康风险。该研究进一步表明,有效的水处理,如煮沸,大大降低了污染水平。然而,人们发现在水管理规程和卫生方面存在缺陷,这在很大程度上导致了水媒疾病的高发生率。具体而言,31%的人口报告出现了与水质不佳有关的健康症状,如腹泻和皮肤感染。研究结果强调,迫切需要加强水处理措施和公共卫生措施,以减少土著人口中水传播疾病的危害。
{"title":"Drinking water quality in the Malaysian indigenous community of Pos Kemar (Perak): Pollution, risks, and household practices","authors":"Sarva Mangala Praveena ,&nbsp;Nurul Shafiqah Sukri ,&nbsp;Aini Saadah Mohd Soad ,&nbsp;Samuel Abiodun Kehinde","doi":"10.1016/j.gexplo.2025.107849","DOIUrl":"10.1016/j.gexplo.2025.107849","url":null,"abstract":"<div><div>Access to clean water continues to be a major obstacle for indigenous communities in remote areas. The objective of this study is to evaluate the extent of pollution in the drinking water of the indigenous tribe community of Pos Kemar (Malaysia), specifically examining the issue of microbiological contamination and the resulting health hazards. Drinking water samples were collected from 108 households and analysed for physicochemical parameters, heavy metals, and microbial contamination, particularly <em>Escherichia coli (E. coli)</em>. In addition, a questionnaire study was carried out to investigate behaviour related to water handling, hygiene, and reported health complaints. The results indicated that although the majority of physicochemical and heavy metal levels were within the Malaysian Drinking Water Quality Standards, the presence of microbiological contamination, namely <em>E. coli</em>, greatly beyond the safely acceptable thresholds in all samples. According to a simplified Quantitative Microbial Risk Assessment, all samples exceeded the World Health Organization health-based target for pathogenic <em>E. coli</em>, indicating a significant health risk from <em>E. coli</em> infection. The study further revealed that effective water treatment, such as boiling, substantially decreased levels of pollution. Nevertheless, deficiencies in water management protocols and sanitation were identified, which greatly contributed to the high occurrence of waterborne illnesses. Specifically, 31 % of the population reported experiencing health symptoms related to inadequate water quality, such as diarrhea and skin infections. The results emphasize the immediate requirement for enhanced water treatment measures and public health approaches to reduce the hazards of waterborne illnesses in indigenous populations.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"278 ","pages":"Article 107849"},"PeriodicalIF":3.4,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144470788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
Journal of Geochemical Exploration
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:604180095
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1