Shen Han , Zhenju Zhou , Xiaohua Deng , Yanshuang Wu , Xi Chen , Abulimiti Aibai , Yong Wang , Xiaoyu Jia , Yanjing Chen
{"title":"中国西部准噶尔西部哈图成因金矿床的成因与流体演化","authors":"Shen Han , Zhenju Zhou , Xiaohua Deng , Yanshuang Wu , Xi Chen , Abulimiti Aibai , Yong Wang , Xiaoyu Jia , Yanjing Chen","doi":"10.1016/j.oregeorev.2024.106238","DOIUrl":null,"url":null,"abstract":"<div><p>The West Junggar in Xinjiang, western China, represents a significant gold mineralization belt hosting over 200 gold deposits, with the Hatu gold deposit being the largest among them. In this study, ore geology and fluid inclusion assemblages of quartz samples from the Hatu gold deposit were investigated in an effort to clarify the mineralization process and its relationship with the geodynamic settings. The mineralization process is delineated into early (pyrite-albite-quartz veins), middle-a (quartz-ankerite veins), middle-b (quartz-ankerite-sulfide-native gold veins), and late (quartz-calcite veins) stages. The early stage veins suggest a compressional setting while the middle-a and middle-b stage veins suggest a tensional shear setting. The late stage veins are typically filled fissures cutting through earlier veins. Scanning electron microscope-cathodoluminescence (SEM-CL) reveals that early stage quartz (Q1) exhibits concentric CL-oscillatory growth zoning, while middle-a stage quartz (Q2a) displays unidirectional zoning and ranges from CL-bright to CL-dark, middle-b stage quartz (Q2b) is CL-bright and weakly zoned, and late-stage euhedral quartz (Q3) shows sector zoning transitioning from CL-gray to CL-dark. Quartz that formed in these stages developed three types of fluid inclusions: pure CO<sub>2</sub> (PC-type), CO<sub>2</sub>–H<sub>2</sub>O (C-type), and H<sub>2</sub>O–NaCl (W-type). The early stage quartz contains C- and W-type fluid inclusions homogenizing at 309–345 °C, while the late stage quartz contains only W-type fluid inclusions with homogenization temperatures of 164–229 °C. Microthermometry of fluid inclusion indicated the evolutionary of the metallogenic fluid from a high-temperature, CO<sub>2</sub>-rich, and minor CH<sub>4</sub> metamorphic fluid to a low-temperature, CO<sub>2</sub>-poor meteoric fluid. From the early to middle-a stages, fluid boiling caused the unloading of ore-forming elements whereas fluid mixing led to the precipitation of polymetallic sulfides and gold in the middle-b stage. Trapping pressures in the middle-b stage were estimated using C-type inclusions, illustrating that gold mineralization took placed at depth of 8.0 km. We propose classifying the Hatu gold deposit as an orogenic deposit, originating from the collisional orogenesis between the Yili-Kazakhstan and Siberian continents in the Late Carboniferous.</p></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":null,"pages":null},"PeriodicalIF":3.2000,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0169136824003718/pdfft?md5=98535fc1189f1adf18e1c10fea9e7746&pid=1-s2.0-S0169136824003718-main.pdf","citationCount":"0","resultStr":"{\"title\":\"Genesis and fluid evolution of the Hatu orogenic gold deposit in the West Junggar, Western China\",\"authors\":\"Shen Han , Zhenju Zhou , Xiaohua Deng , Yanshuang Wu , Xi Chen , Abulimiti Aibai , Yong Wang , Xiaoyu Jia , Yanjing Chen\",\"doi\":\"10.1016/j.oregeorev.2024.106238\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The West Junggar in Xinjiang, western China, represents a significant gold mineralization belt hosting over 200 gold deposits, with the Hatu gold deposit being the largest among them. In this study, ore geology and fluid inclusion assemblages of quartz samples from the Hatu gold deposit were investigated in an effort to clarify the mineralization process and its relationship with the geodynamic settings. The mineralization process is delineated into early (pyrite-albite-quartz veins), middle-a (quartz-ankerite veins), middle-b (quartz-ankerite-sulfide-native gold veins), and late (quartz-calcite veins) stages. The early stage veins suggest a compressional setting while the middle-a and middle-b stage veins suggest a tensional shear setting. The late stage veins are typically filled fissures cutting through earlier veins. Scanning electron microscope-cathodoluminescence (SEM-CL) reveals that early stage quartz (Q1) exhibits concentric CL-oscillatory growth zoning, while middle-a stage quartz (Q2a) displays unidirectional zoning and ranges from CL-bright to CL-dark, middle-b stage quartz (Q2b) is CL-bright and weakly zoned, and late-stage euhedral quartz (Q3) shows sector zoning transitioning from CL-gray to CL-dark. Quartz that formed in these stages developed three types of fluid inclusions: pure CO<sub>2</sub> (PC-type), CO<sub>2</sub>–H<sub>2</sub>O (C-type), and H<sub>2</sub>O–NaCl (W-type). The early stage quartz contains C- and W-type fluid inclusions homogenizing at 309–345 °C, while the late stage quartz contains only W-type fluid inclusions with homogenization temperatures of 164–229 °C. Microthermometry of fluid inclusion indicated the evolutionary of the metallogenic fluid from a high-temperature, CO<sub>2</sub>-rich, and minor CH<sub>4</sub> metamorphic fluid to a low-temperature, CO<sub>2</sub>-poor meteoric fluid. From the early to middle-a stages, fluid boiling caused the unloading of ore-forming elements whereas fluid mixing led to the precipitation of polymetallic sulfides and gold in the middle-b stage. Trapping pressures in the middle-b stage were estimated using C-type inclusions, illustrating that gold mineralization took placed at depth of 8.0 km. We propose classifying the Hatu gold deposit as an orogenic deposit, originating from the collisional orogenesis between the Yili-Kazakhstan and Siberian continents in the Late Carboniferous.</p></div>\",\"PeriodicalId\":19644,\"journal\":{\"name\":\"Ore Geology Reviews\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.2000,\"publicationDate\":\"2024-09-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.sciencedirect.com/science/article/pii/S0169136824003718/pdfft?md5=98535fc1189f1adf18e1c10fea9e7746&pid=1-s2.0-S0169136824003718-main.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Ore Geology Reviews\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0169136824003718\",\"RegionNum\":2,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"GEOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ore Geology Reviews","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0169136824003718","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOLOGY","Score":null,"Total":0}
引用次数: 0
摘要
中国西部新疆的西准噶尔是一个重要的金成矿带,拥有 200 多个金矿床,其中哈图金矿床是最大的金矿床。本研究对哈图金矿床石英样品的矿石地质和流体包裹体组合进行了研究,旨在阐明其成矿过程及其与地球动力学环境的关系。矿化过程被划分为早期(黄铁矿-重晶石-石英脉)、中期-a(石英-钾长石脉)、中期-b(石英-钾长石-硫化物-原生金脉)和晚期(石英-方解石脉)阶段。早期的矿脉显示出一种压缩性环境,而中期-a 和中期-b 阶段的矿脉则显示出一种拉伸剪切性环境。晚期矿脉通常是切割早期矿脉的充填裂隙。扫描电子显微镜-阴极电致发光(SEM-CL)显示,早期石英(Q1)呈现同心CL-振荡生长分带,中期-a期石英(Q2a)呈现单向分带,从CL-亮到CL-暗,中期-b期石英(Q2b)为CL-亮弱分带,晚期八面体石英(Q3)呈现扇形分带,从CL-灰过渡到CL-暗。在这些阶段形成的石英发育出三种类型的流体包裹体:纯 CO2(PC 型)、CO2-H2O(C 型)和 H2O-NaCl(W 型)。早期石英含有 C 型和 W 型流体包裹体,均化温度为 309-345 ℃,而晚期石英仅含有 W 型流体包裹体,均化温度为 164-229 ℃。流体包裹体的显微测温表明,成矿流体从高温、富含 CO2 和少量 CH4 的变质流体演变为低温、贫 CO2 的陨石流体。从早期到中期a阶段,流体沸腾导致成矿元素卸载,而流体混合则导致多金属硫化物和金在中期b阶段沉淀。利用 C 型包裹体估算了中-b 阶段的包裹压力,说明金矿化位于 8.0 千米深处。我们建议将哈图金矿床归类为造山运动矿床,源于晚石炭纪伊犁-哈萨克斯坦大陆和西伯利亚大陆之间的碰撞造山运动。
Genesis and fluid evolution of the Hatu orogenic gold deposit in the West Junggar, Western China
The West Junggar in Xinjiang, western China, represents a significant gold mineralization belt hosting over 200 gold deposits, with the Hatu gold deposit being the largest among them. In this study, ore geology and fluid inclusion assemblages of quartz samples from the Hatu gold deposit were investigated in an effort to clarify the mineralization process and its relationship with the geodynamic settings. The mineralization process is delineated into early (pyrite-albite-quartz veins), middle-a (quartz-ankerite veins), middle-b (quartz-ankerite-sulfide-native gold veins), and late (quartz-calcite veins) stages. The early stage veins suggest a compressional setting while the middle-a and middle-b stage veins suggest a tensional shear setting. The late stage veins are typically filled fissures cutting through earlier veins. Scanning electron microscope-cathodoluminescence (SEM-CL) reveals that early stage quartz (Q1) exhibits concentric CL-oscillatory growth zoning, while middle-a stage quartz (Q2a) displays unidirectional zoning and ranges from CL-bright to CL-dark, middle-b stage quartz (Q2b) is CL-bright and weakly zoned, and late-stage euhedral quartz (Q3) shows sector zoning transitioning from CL-gray to CL-dark. Quartz that formed in these stages developed three types of fluid inclusions: pure CO2 (PC-type), CO2–H2O (C-type), and H2O–NaCl (W-type). The early stage quartz contains C- and W-type fluid inclusions homogenizing at 309–345 °C, while the late stage quartz contains only W-type fluid inclusions with homogenization temperatures of 164–229 °C. Microthermometry of fluid inclusion indicated the evolutionary of the metallogenic fluid from a high-temperature, CO2-rich, and minor CH4 metamorphic fluid to a low-temperature, CO2-poor meteoric fluid. From the early to middle-a stages, fluid boiling caused the unloading of ore-forming elements whereas fluid mixing led to the precipitation of polymetallic sulfides and gold in the middle-b stage. Trapping pressures in the middle-b stage were estimated using C-type inclusions, illustrating that gold mineralization took placed at depth of 8.0 km. We propose classifying the Hatu gold deposit as an orogenic deposit, originating from the collisional orogenesis between the Yili-Kazakhstan and Siberian continents in the Late Carboniferous.
期刊介绍:
Ore Geology Reviews aims to familiarize all earth scientists with recent advances in a number of interconnected disciplines related to the study of, and search for, ore deposits. The reviews range from brief to longer contributions, but the journal preferentially publishes manuscripts that fill the niche between the commonly shorter journal articles and the comprehensive book coverages, and thus has a special appeal to many authors and readers.