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A comparison study of tungsten-bearing granite and related mineralization in the northern jiangxi-southern Anhui provinces and southern jiangxi Province in South China

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Science China Earth Sciences 2017年第11期60卷 1942-1958页

作者： SU HuiMin jiang shaoyong State Key Laboratory of Geological Processes and Mineral Resources Collaborative Innovation Center for Exploration of Strategic Mineral Resources Faculty of Earth Resources China University of Geosciences State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University

The southern jiangxi Province(SJP) and northern jiangxi-southern Anhui provinces(NJSAP) are the two most important tungsten metallogenic districts in South China. The SJP district is a well-known tungsten producer in South China where distributes several ore concentrated areas such as the "Chongyi-Dayu-Shangyou", "Yudu" and "Longnan-Quanan-Dingnan"areas, with many large and super large tungsten deposits including the famous Xihuashan, Piaotang, Pangushan and Dajishan deposits. In recent years, major prospecting breakthrough for W-polymetallic resources has been made in the NJSAP *** large and super large W-Cu(Mo) deposits, such as the Dahutang, Zhuxi, Dongyuan and Baizhangyan deposits, are discovered. These deposits are all genetically associated with the Yanshanian(Mesozoic) granitic magmatism. In this study, a systematic comparison of the temporal and spatial distribution, petrology, geochronology, and geochemical characteristics of the tungsten-bearing granites between the SJP and NJSAP districts has been made, with an aim to improving the understanding of the petrogenesis of the granites and associated metal enrichment mechanisms in the two tungsten ore districts in South China. The following conclusions can be drawn:(1) The ages of the tungsten-bearing granites and associated mineralization are different in the two districts, in the SJP district the ages are mainly concentrated in 165–150 Ma, whereas in the NJSAP district it displays two age periods, one is 150–140 Ma(Late Jurassic-Early Cretaceous), and the other is 135–120 Ma(Early Cretaceous).(2) The tungsten-bearing granites from both the NJSAP and SJP districts are highly fractionated granitic rocks, but the SJP granites have experienced higher degree of fractional crystallization and more extensive fluid metasomatism than the NJSAP granites.(3) The petrogeneses of the tungsten-bearing granites from the two districts are different, those from the NJSAP district originated from partial melting

关键词： Tungsten-bearing granites Material sources Metallogenic characteristics Northern jiangxi-southern Anhui provinces Southern jiangxi Province

Trace and Rare Earth Element Characteristics in Fe-Mn Carbonates Associated with Stratiform Ag-Pb-Zn Mineralization from the Lengshuikeng Ore District, jiangxi Province: Implications for Their Genesis and Depositional Environment

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Journal of Earth Science 2016年第4期27卷 571-583页

作者： Qing Li shaoyong jiang State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Resources Collaborative Innovation Center for Exploration of Strategic Mineral Resources China University of Geosciences

We performed a systematic trace and rare earth element analysis for the bedded Fe-Mn carbonate rocks related to the stratiform Ag-Pb-Zn mineralization in the Lengshuikeng ore district, jiangxi Province, South China. Three types of Fe-Mn carbonates are distinguished, namely, the massive, breccia, and vein types. Both carbonate and silicate fractions in the samples are analyzed for their trace and rare earth element concentrations using a step acid-leaching technique. Our results show that the carbonate fractions in the massive type samples have the lowest REE concentrations but pronounced positive Eu and Y anomalies with Eu/Eu＊ value from 1.3 to 6.2 and Y/Ho value from 40.1 to 59.5, and similar characteristics are also shown for the silicate fractions in the massive type samples（Eu/Eu＊=1.0-6.7, Y/Ho=20.7-55.1）. These REE characteristics are similar to those of Sedex type massive sulfide deposits worldwide, and we suggest that the massive type Fe-Mn carbonate rocks were likely formed from an exhalative volcanic-hydrothermal fluid feeding the depression basin of a volcanic lake. The high concentrations of redox-sensitive elements and ratios such as U/Th, V/Cr and V/（V＋Ni） indicate a dysoxic environment for the Fe-Mn carbonate deposition. In contrast, the breccia type and vein type Fe-Mn carbonate samples show different trace and rare earth element features from those of massive type samples, and they are more similar to the volcanic rocks and magmatic-hydrothermal fluids in the Lengshuikeng ore district and may reflect strong overprinting from volcanic and sub-volcanic magmatism related to the porphyry type mineralization in the district.

关键词： Fe-Mn carbonate trace and rare earth elements stratiform Ag-Pb-Zn orebody Leng-shuikeng ore district South China.

湖北庙垭碱性杂岩体中铌成矿作用:来自金红石矿物学和年代学的制约

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高校地质学报 2024年第3期30卷 345-361页

作者：应元灿陈唯柳加俊杨帆蒋少涌昆明理工大学国土资源工程学院昆明650093 中国地质大学地质过程与矿产资源国家重点实验室武汉430074

庙垭碱性杂岩体主要由富Nb和REE的碳酸岩和正长岩组成,已探明Nb_(2)O_(5)储量93万吨,平均品位0.12%,是国内仅次于白云鄂博的碳酸岩型Nb-REE矿床。前人对碳酸岩成因及稀土成矿作用开展了大量的研究,但对正长岩中铌的赋存状态和富集机制... 详细信息

庙垭碱性杂岩体主要由富Nb和REE的碳酸岩和正长岩组成,已探明Nb_(2)O_(5)储量93万吨,平均品位0.12%,是国内仅次于白云鄂博的碳酸岩型Nb-REE矿床。前人对碳酸岩成因及稀土成矿作用开展了大量的研究,但对正长岩中铌的赋存状态和富集机制尚不清楚。文章在野外地质调查的基础上,结合TIMA、电子探针和LA-ICP-MS分析技术对正长岩中含铌矿物开展了详细的岩相学、矿物化学和U-Pb年代学研究。结果显示庙垭正长岩中主要含铌矿物为金红石,根据矿物结构和化学组成可划分为岩浆金红石和热液金红石两类。其中岩浆金红石少见,而热液金红石在各类正长岩中广泛发育,多呈浸染状沿原生金红石边缘或裂隙分布,或与黑云母和钛铁矿等其它矿物紧密共生。在化学组成上,原生金红石显示低Nb2O5(1.43%~2.56%)、FeO(0.74%~1.01%)和微量元素(如Ta、Cr、V、W、Mo、Sb)含量特征;而热液金红石具有不同程度的Nb_(2)O_(5)(3.48%~20.68%)、FeO(1.18%~6.92%)和微量元素富集特征。原位微区U-Pb定年显示两类金红石形成于不同的时代,原生金红石形成时代为446±21 Ma,而热液金红石形成时代为240±19 Ma,表明正长岩中铌矿化经历了早古生代岩浆阶段的初次富集和三叠纪热液交代阶段的二次富集。综上,我们认为庙垭杂岩体中铌富集成矿受控于岩浆和热液过程。在早古生代岩浆阶段,正长岩中Nb主要以晶格置换的方式进入早期金红石、黑云母等含钛矿物中;在三叠纪热液交代阶段,热液流体可分解黑云母形成次生富铌金红石和铌铁矿,亦或交代早期金红石和钛铁矿最终形成富铌金红石。

关键词：碱性正长岩铌矿床金红石成矿作用庙垭

伟晶岩结晶动力学和热力学及稀有金属超常富集成矿机制

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地质学报 2024年第5期98卷 1489-1506页

作者：左达昇杨可魏海珍王勤蒋少涌林和丰环淳许志琴南京大学地球科学与工程学院内生金属矿床成矿机制研究国家重点实验室江苏南京210023 南京大学地球科学与工程学院大陆动力学研究院江苏南京210023 中国地质大学(武汉)紧缺战略矿产资源协同创新中心地质过程与矿产资源国家重点实验室资源学院湖北武汉430074

本文综述了伟晶岩结晶动力学、热力学和伟晶岩熔体稀有金属元素实现超常富集成矿的机制。结晶动力学涉及成核动力学和晶体生长动力学两个方面。低成核速率和高晶体生长速率是伟晶岩结晶动力学的重要特征,在结晶过程受到水、助溶剂以及... 详细信息

本文综述了伟晶岩结晶动力学、热力学和伟晶岩熔体稀有金属元素实现超常富集成矿的机制。结晶动力学涉及成核动力学和晶体生长动力学两个方面。低成核速率和高晶体生长速率是伟晶岩结晶动力学的重要特征,在结晶过程受到水、助溶剂以及过冷条件三个因素共同制约。伟晶岩熔体的相态(超临界态)可能在伟晶岩形成和稀有金属元素超常富集中扮演重要角色。花岗伟晶岩稀有金属超常富集程度受到岩浆源区成分、岩浆结晶分异过程与熔体化学成分等因素的控制。花岗质岩浆高度分异结晶或者变质沉积岩部分熔融直接形成的成矿伟晶岩熔体均需要源岩中稀有金属元素预富集。深熔作用产生的低程度、小体积的伟晶岩熔体具有更高的稀有金属元素成矿潜力。在岩浆分异演化过程中,稀有金属元素的超常富集主要通过超临界熔体/流体、岩浆熔体作用、过冷作用实现。超临界熔体/流体发生熔体-流体不混溶作用使稀有金属元素在熔体相和流体相间再分配和富集;岩浆熔离作用使稀有金属元素选择性分配到富挥发分的熔体中,导致稀有金属元素再次富集;过冷作用降低稀有金属矿物结晶的饱和浓度,促进稀有金属矿物结晶。熔体的化学成分(如挥发分)直接影响熔体的物理、化学性质。例如,挥发分的富集能够降低熔体黏度,促进岩浆分异结晶过程。挥发分和稀有金属元素的亲和性也控制稀有金属元素在不同相熔体中的分配和富集,显著增加稀有金属元素的溶解度和迁移富集能力,有助于伟晶岩中稀有金属超常富集和成矿。

关键词：伟晶岩结晶动力学结晶热力学稀有金属元素超常富集成矿

伟晶岩中不同副矿物U-Pb同位素定年和示踪的问题与应用

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地质学报 2024年第5期98卷 1573-1599页

作者：蒋少涌张浩翔刘思祺李雯恬尹燕梁车玉滢苏慧敏中国地质大学地质过程与矿产资源国家重点实验室资源学院紧缺战略矿产资源协同创新中心湖北武汉430074

定年和示踪一直是伟晶岩成岩成矿过程和稀有金属富集机制研究的关键问题。副矿物不仅是伟晶岩中稀有稀土元素的重要载体,还蕴含丰富的微量元素并常常具有较高的U-Th含量,是研究伟晶岩年代学、成岩成矿过程和物质源区的“理想探针”。伟... 详细信息

定年和示踪一直是伟晶岩成岩成矿过程和稀有金属富集机制研究的关键问题。副矿物不仅是伟晶岩中稀有稀土元素的重要载体,还蕴含丰富的微量元素并常常具有较高的U-Th含量,是研究伟晶岩年代学、成岩成矿过程和物质源区的“理想探针”。伟晶岩中常用的适合于U-Pb同位素定年的副矿物有锆石、铌钽铁矿、独居石、锡石、榍石、褐帘石、磷钇矿和磷灰石等。由于封闭温度、矿物学特性和不同性质流体中元素行为的差异,伟晶岩中不同副矿物的U-Pb系统常表现出复杂的年龄谱系,可能记录了伟晶岩中潜在的后期地质过程,如:自交代、后期变质与流体改造等。因此,基于前期光学显微镜、扫描电镜、冷阴极发光、激光拉曼光谱分析等矿物微观结构研究,对不同期次或世代的副矿物进行原位微区U-Pb定年及主微量元素和同位素地球化学分析,对于全面认知多期地质事件和伟晶岩成岩成矿过程演化历史,进而更准确地构建其构造-岩浆-热液-成矿作用时空框架具有重要的科学意义。

关键词：伟晶岩副矿物 U-Pb同位素定年地球化学示踪

Br/Cl,I/Cl and chlorine isotopic compositions of pore water in shallow sediments：implications for the fluid sources in the Dongsha area,northern South China Sea

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Acta Oceanologica Sinica 2017年第4期36卷 31-36页

作者： LI Yanping jiang shaoyong YANG Tao Ministry of Education Key Laboratory for Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Resources China University of Geosciences Wuhan 430074 China Collaborative Innovation Center of South China Sea Studies Nanjing 210093 China

The Dongsha area is one of the most promising target areas for gas hydrate exploration in the South China Sea（SCS）.The study of pore water geochemistry has played a key role in Chinese gas hydrate ***/Cl,I/Cl and δ37Cl in pore water were applied here in tracing gas hydrate occurrence,chemical evolution of pore fluids and water/rock interactions in low temperature sediment *** samples were collected from Sites HD255 PC and HD309 PC in the Dongsha area in *** Site HD255 PC,we found the elevated Br/Cl,I/Cl and decreased SO_4/Cl at the depth of 4–5 m,suggestive of a laterally migrated fluid probably generated from the gas hydrate *** range of δ37Cl is –0.54‰ to ＋0.96‰,and positive δ^（37）Cl at 4–5 m interval should be related with different diffusion rates between ^（35）Cl and ^（37）*** Site HD309 PC,a laterally migrated fluid was also found at the depth of 3–4 m,with the Br/Cl two times to that of the seawater and decreased I/Cl,indicating the fluid has no relationship with the gas *** this site,the chlorine isotopic composition varies from –0.7‰ to＋1.9‰.Extra high Br/Cl might relate with the deep generated *** higher temperature and pressure,the Br/Cl of the fluid is elevated during the hydrous silicate formation,while positive δ37Cl is also associated with the same mechanism.

关键词： halogen chlorine isotope pore water Dongsha area

Zircon U-Pb geochronology,Hf isotopic composition and geological implications of the rhyodacite and rhyodacitic porphyry in the Xiangshan uranium ore field,jiangxi Province,China

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Science China Earth Sciences 2010年第10期53卷 1411-1426页

作者： YANG ShuiYuan jiang shaoyong jiang YaoHui ZHAO KuiDong FAN HongHai State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing 210093China Beijing Research Institute of Uranium Geology Beijing 100029China

The Xiangshan uranium ore field is the largest volcanic rock hosted uranium deposit in *** host rock is a volcanic intrusive complex,including rhyodacite,porphyroclastic lava and late stage sub-volcanic *** this study,zircons from an early stage rhyodacite and a late stage rhyodacite porphyry were dated by SHRIMP and LA-ICP-MS U-Pb methods,and their Hf isotopic compositions were measured by LA-MC-ICP-MS.206Pb/238U ages of 135.1±1.7 and 134.8±1.1 Ma were obtained for the rhyodacite and rhyodacitic porphyry,*** accurate ages indicate that the Xiangshan volcanic-intrusive complex formed in the Early Cretaceous rather than in the Late Jurassic,as concluded in some previous *** the Early Cretaceous,the tectonic setting of the area has evolved into a back-arc extensional setting,possibly related to subduction of the paleo-Pacific *** close ages of the(early) eruptive rhyodacite and the(late) hypabyssal rhyodacitic porphyry shows that the Xiangshan volcanism was intensive and concentrated in a short *** from the rhyodacite show negative εHf(t) values of-5.7 to-8.5,with Hf depleted mantle model ages between 1550 and 1720 Ma,whereas zircons from the rhyodacitic porphyry yield εHf(t) values of-6.9 to-10.1 and Hf model ages between 1621 and 1823 *** zircon Hf model ages are similar to the whole rock Nd model ages(1486 to 1911 Ma).Combined with other geochemical characteristics,the Xiangshan rhyodacite and rhyodacitic porphyry may have been derived from partial melting of the Paleo-Mesoproterozoic metamorphic rocks from the Xiangshan basement,without any significant addition of mantle-derived *** of basement of this age is also supported by finding a Paleoproterozoic xenocrystic zircon core in the rhyodacite sample.

关键词： rhyodacite rhyodacitic porphyry U-Pb zircon age Hf isotope Xiangshan jiangxi Province

Types and Origin of Dolostones in Tarim Basin, Northwest China: Petrographic and Geochemical Evidence

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Acta Geologica Sinica(English Edition) 2013年第2期87卷 467-485页

作者： CHEN Yongquan ZHOU Xinyuan jiang shaoyong ZHAO Kuidong Tarim Oilfield Company State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University

In the Tarim Basin of northwestern China hydrocarbon deposits have been discovered in parts of the thick strata of Cambrian dolostones. Based on petrographic study, six types of dolostone have been distinguished： Type-l, pink mud-bearing silty crystalline dolostone （PMSD）; Type-2, gypsum- and salt-bearing fine crystalline dolostone （GSFD）; Type-3, fine crystalline dolostone with dolomite crystals with cloudy core and clear rim （CCFD）; Type-4, deep gray mud-bearing silty crystalline dolostone （GMSD）; Type-5, euhedral coarse crystalline dolostone （ECD）; and Type-6, xenotopic coarse crystalline dolostone （XCD）. Applying petrographic and geochemical methods, the genesis of the dolostones is studied in this paper. Normally, Type-I dolostone shows U- and Mo- depleted characteristics, reflecting a more oxidized formation environment; High ~80 and the purple color are consistent with formation of Sabkha dolostones on a supratidal flat. Types 2, 3, 4 dolostones show strata formation, similar REE patterns and 87Sr/86Sr ratios with contemporaneous limestones, suggesting a penecontemporaneous origin from seawater. Types 5 and 6 dolostones commonly occur as interbedded rocks, indicating secondary genesis after diagenesis. Type-6 dolostone has the highest order degree （OD） values （average 0.86）, the lowest oxygen isotope values and positive Eu anomalies, which are consistent with previously reported hydrothermal dolostones. Differently, Type-5 shows euhedral texture, higher δ80 value, similar REE characteristic and 87Sr/86Sr ratios in comparison with contemporaneous limestones, suggesting that this type might have been dolomitized by down- transferring evaporated seawater during shallow burial stage. Dolostone fluid sources, formation environments and crystallizing dynamics are summarized and possible genetic models for the six types are proposed.

关键词： dolomite origin geochemistry petrology Cambrian

Mineral Chemistry of Melanite from Calcitic Ijolite, the Oka Carbonatite Complex, Canada: Implications for Multi-Pulse Magma Mixing

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Journal of Earth Science 2016年第4期27卷 599-610页

作者： Wei Chen Weiqi Zhang Antonio Simonetti shaoyong jiang State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Department of Civil & Environmental Engineering & Earth Sciences University of Notre Dame State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University

Ti-rich garnet is found within calcitic ijolite from the Oka carbonatite complex in Canada, which is characterized by 58%-73% andradite component（2.12 wt.%-4.18 wt.% TiO_2） and classified as melanite. The garnet displays complex zoning and contains abundant high field strength elements（HFSEs） and rare earth elements（REEs）. Three groups（Ⅰ, Ⅱ, Ⅲ） have been identified based on their petrographic nature. Compared to groups Ⅱ and Ⅲ, Group Ⅰ garnet cores contain higher TiO_2, Mg O, HFSE, and REE and lower SiO_2 abundances. The distinct chemical and petrographic signatures of the investigated garnets cannot be attributed to simple closed system crystallization, but they are consistent with the multi-pulse magma mixing. Combined with previously reported U-Pb ages for apatite from the calcitic ijolite, at least three stages of magma evolution and subsequent mixing have been involved in the generation of calcitic ijolite at Oka. The early-formed melt that generated Group I garnet core was later mixed with at least two small-volume, more evolved melts. The intermediate stage melt formed the remaining garnet along with some pyroxene, calcite, nepheline, and apatite at 127±3.6 Ma. The youngest, most evolved melt generated the majority of pyroxene, calcite, nepheline, and apatite within the calcitic ijolite at 115±3.1 Ma.

关键词： melanite garnet calcitic ijolite Oka magma mixing.