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| 1 | 三江北段治多-玉树地区火山成因铜多金属矿床地质特征及成矿构造环境显示文摘三江成矿带北段治多-玉树地区已显示出较大的铜多金属矿成矿潜力。在已有研究成果的基础上,结合详细的野外调查和室内研究,对三江北段治多-玉树地区新发现的典型铜多金属矿床的地质特征、成因类型和成矿构造环境进行了综述。这些矿床普遍赋存于中酸性火山岩中,空间上具'火山碎屑岩-矿体-热水沉积岩'的分布特征。矿体多为层状、似层状,且矿石品位较高。对比研究表明,治多-玉树地区铜多金属矿床地质特征与四川呷村矿床和日本'黑矿'矿床相似,成矿流体可能系岩浆水和海水的混合流体;成矿物质可能源于岛弧岩浆作用,并含有热液交代围岩所萃取的金属元素。研究结果表明该区以火山岩为赋矿围岩的铜多金属矿床应归属为VHMS型,成矿构造环境可能与晚三叠世甘孜-理塘洋向南俯冲的大洋岛弧-大陆边缘岛弧环境有关。 | 张飞 魏俊浩 王凤林 赵少卿 詹小飞 徐佳富 刘颜 甘觐荣 刘晓阳 | 2017 | 地质科技情报2017，36，1： | 16 |
| 2 | 东昆仑东段坑得弄舍多金属矿床Pb-Zn与Au-Ag成矿关系研究显示文摘坑得弄舍为近年在东昆仑成矿带内发现的大型Au-Ag-Pb-Zn多金属矿床,但该矿床富Pb-Zn与富Au矿体之间的成因联系备受争议。鉴于此,本文以这两类矿体作为研究对象,对矿化、蚀变、流体包裹体等特征开展对比研究,并对Au、Ag、Pb、Zn等成矿元素的相关性进行统计分析。研究表明,矿区矿体从北到南具有富Pb-Zn→富Au的变化趋势,两者之间为逐渐过渡关系,对应的围岩蚀变组合从硅化-绿帘石化向重晶石化-大理岩化-硅化转变。另外,矿区内富Pb-Zn矿石的结构构造指示其为热水沉积成因并叠加后期改造,而富Au矿石的结构构造则指示其为热液成因。流体包裹体研究表明,矿区内富Pb-Zn矿石对应的成矿流体具有低温(集中于150~170°C)、中低盐度(1.74%~10.11%NaCl_(eqv))的特征,富Au矿石对应的成矿流体显示中低温(集中于130~250°C)、中低盐度(0.35%~10.24%NaCl_(eqv))的特征。矿区内成矿元素相关性分析表明,Pb与Zn、Au与Ag元素含量之间均具有较好相关性(相关系数r>0.25),Au与Pb、Zn元素含量相关性较差(相关系数r<0.15),但当Au品位较高时,Au与Pb元素之间相关性相对增强,这可能与后期的热液叠加成矿作用有关。综上,坑得弄舍多金属矿床应存在两期成矿作用,早期为Pb-Zn成矿期,主要形成Pb-Zn矿体,成矿流体来源于岩浆水与海水的混合,具有热水沉积成因特征;晚期为Au-Ag成矿期,主要形成Au-Ag矿体,同时对早期Pb-Zn矿体有一定的叠加改造作用,并产生Pb、Zn的再富集,具有热液成因特征,晚期成矿流体可能主要源于岩浆水,并有大气降水的混入。 | 刘颜 付乐兵 王凤林 魏俊浩 管波 谭俊 杨宝荣 汪殿钟 | 2018 | 大地构造与成矿学2018，42，3： | 8 |
| 3 | Fluid Inclusions and Metallization of the Kendekeke Polymetallic Deposit in Qinghai Province, China显示文摘The Kendekeke polymetallic deposit, located in the middle part of the magmatic arc belt of Qimantag on the southwestern margin of the Qaidam Basin, is a polygenetic compound deposit in the Qimantag metallogenic belt of Qinghai Province. Multi-periodic ore-forming processes occurred in this deposit, including early-stage iron mineralization and lead-zinc-gold-polymetallic mineralization which was controlled by later hydrothermal process. The characteristics of the ore-forming fluids and mineralization were discussed by using the fluid inclusion petrography, Laser Raman Spectrum and micro-thermometry methods. Three stages, namely, S1-stage(copper-iron-sulfide stage), S2-stage(lead-zinc-sulfide stage) and C-stage(carbonate stage) were included in the hydrothermal process as indicated by the results of this study. The fluid inclusions are in three types: aqueous inclusion(type I), CO2-aqueous inclusion(type II) and pure CO2 inclusion(type III). Type I inclusions were observed in the S1-stage, having homogenization temperature at 240–320oC, and salinities ranging from 19.8% to 25.0%(wt % NaCl equiv.). All three types of inclusions, existing as immiscible inclusion assemblages, were presented in the S2-stage, with the lowest homogenization temperature ranging from 175 oC to 295oC, which represents the metallogenic temperature of the S2-stage. The salinities of these inclusions are in the range of 1.5% to 16%. The fluid inclusions in the C-stage belong to types I, II and III, having homogenization temperatures at 120–210oC, and salinities ranging from 0.9% to 14.5%. These observations indicate that the ore-forming fluids evolved from high-temperature to lowtemperature, from high-salinity to low-salinity, from homogenization to immiscible separation. Results of Laser Raman Spectroscopy show that high density of CO2 and CH4 were found as gas compositions in the inclusions. CO2, worked as the pH buffer of ore-forming fluids, together with reduction of organic gases(i.e. CH4, etc), affected the transport and sediment of the minerals. The fluid system alternated between open and close systems, namely, between lithostatic pressure and hydrostatic pressure systems. The calculated metallogenic pressures are in the range of 30 to 87 Mpa corresponding to 3 km mineralization depth. Under the influence of tectonic movements, immiscible separation occurred in the original ore-forming fluids, which were derived from the previous highsalinity, high-temperature magmatic fluids. The separation of CO2 changed the physicochemical properties and composition of the original fluids, and then diluted by mixing with extraneous fluids such as meteoric water and groundwater, and metallogenic materials in the fluids such as lead, zinc and gold were precipitated. | HUANG Min LAI Jianqing MO Qingyun | 2014 | Acta Geologica Sinica(English Edition)2014，88，2： | 8 |
| 4 | 山西灵丘县梨园金矿流体包裹体特征及成矿作用显示文摘山西梨园金矿位于太行山构造-岩浆-多金属成矿带上,矿体赋存于北北东向的构造带中,矿床热液作用包括石英脉阶段(A)、石英-黄铁矿阶段(B)、石英-多金属硫化物阶段(C)和石英-碳酸盐阶段(D)。B、C、D阶段的石英中发育3类包裹体:气液两相包裹体(Ⅰ型)、水溶液-CO2包裹体(Ⅱ型)以及纯CO2包裹体(Ⅲ型)。B阶段发育Ⅰ型包裹体、部分Ⅱ型及Ⅲ型包裹体,均一温度集中于230~350℃,盐度为1.82%~12.63%;C阶段发育Ⅰ型包裹体,Ⅱ型及Ⅲ型包裹体明显增多,均一温度集中于200~330℃,盐度为1.82%~9.71%;D阶段主要发育Ⅰ型包裹体,均一温度集中于140~170℃,盐度为1.16%~9.58%。包裹体气相成分含有较高密度的CO2和CO、N2、H2、CH4等,液相成分主要为Ca2+、Na+、K+、SO42-、Cl-、F-。估算成矿压力为68~114 MPa,对应的捕获温度为200~430℃,估算最大成矿深度为4.3km。梨园金矿成矿流体为低盐度、中低温、富CO2的Ca2+(Na+、K+)-SO42-(Cl-、F-)-H2O-CO2体系,可能为后期岩浆热液流体。矿床形成于陆内造山环境,为受断裂破碎带控制的岩浆热液蚀变岩型金矿。 | 鞠培姣 赖健清 杨洪基 王乐进 宋吉杰 李龙义 徐兴保 董文国 杨冰 | 2015 | 中国有色金属学报2015，25，9： | 7 |
| 5 | A New Method for Determining Fluid Compositions in the H_2O-NaClCaCl_2 System with Cryogenic Raman Spectroscopy显示文摘Raman peaks of various hydrates in the H2O-NaCl-CaCl2 system have been previously identified,but a quantitative relationship between the Raman peaks and XNaCl(i.e.,NaCl/(NaCl+CaCl2)) has not been established,mainly due to the difficulty to freeze the solutions.This problem was solved by adding alumina powder to the solutions to facilitate nucleation of crystals.Cryogenic(-185oC) Raman spectroscopic studies of alumina-spiced solutions indicate that XNaCl is linearly correlated with the total peak area fraction of hydrohalite.Capsules of solutions made from silica capillary were prepared to simulate fluid inclusions.Most of these artificial fluid inclusions could not be totally frozen even at temperatures as low as-185 oC,and the total peak area fraction of hydrohalite is not correlated linearly with XNaCl.However,the degree of deviation(?XNaCl) from the linear correlation established earlier is related to the amount of residual solution,which is reflected by the ratio(r) of the baseline 'bump' area,resulting from the interstitial unfrozen brine near 3435 cm-1,and the total hydrate peak area between 3350 and 3600 cm-1.A linear correlation between ?XNaCl and r is established to estimate XNaCl from cryogenic Raman spectroscopic analysis for fluid inclusions. | CHI Guoxiang CHU Haixia Ryan SCOTT CHOU I-Ming | 2014 | Acta Geologica Sinica(English Edition)2014，88，4： | 7 |
| 6 | Geochemical Characteristics and Sources of Ore-forming Fluids of the Mayuan Pb-Zn Deposit,Nanzheng,Shaanxi,China显示文摘The Mayuan stratabound Pb-Zn deposit in Nanzheng,Shaanxi Province,is located in the northern margin of the Yangtze Plate,in the southern margin of the Beiba Arch.The orebodies are stratiform and hosted in breciated dolostone of the Sinian Dengying Formation.The ore minerals are primarily sphalerite and galena,and the gangue minerals comprise of dolomite,quartz,barite,calcite and solid bitumen.Fluid inclusions from ore-stage quartz and calcite have homogenization tempreatures from 98 to 337℃ and salinities from 7.7 wt%to 22.2 wt%(NaCl equiv.).The vapor phase of the inclusions is mainly composed of CH_4 with minor CO_2 and H_2S.The δD_(fluid) values of fluid inclusions in quartz and calcite display a range from-68‰ to-113‰(SMOW),and the δ^(18)O_(fluid)values calculated from δ^(18)O_(quartz) and δ^(18)O_(calcite) values range from 4.5‰ to 16.7‰(SMOW).These data suggest that the ore-forming fluids may have been derived from evaporitic sea water that had reacted with organic matter.The δ^(13)C_(CH4) values of CH_4 in fluid inclusions range from-37.2‰ to-21.0‰(PDB),suggesting that the CH_4 in the ore-forming fluids was mainly derived from organic matter.This,together with the abundance of solid bitumen in the ores,suggest that organic matter played an important role in mineralization,and that the thermochemical sulfate reduction(TSR) was the main mechanism of sulfide precipitation.The Mayuan Pb-Zn deposit is a carbonate-hosted epigenetic deposit that may be classified as a Mississippi Valley type(MVT) deposit. | LIU Shuwen LI Ronxi CHI Guoxiang ZENG Rong LIU Lingfang SHI Shun | 2015 | Acta Geologica Sinica(English Edition)2015，89，3： | 5 |
| 7 | Geochemistry of the Batang Group in the Zhaokalong Area, Yushu, Qinghai: Implications for the Late Triassic Tectonism in the Northern Sanjiang Region, China显示文摘The Batang Group in the Zhaokalong area not only hosts an important Fe-Cu polymetallic deposit but also reveal important insights for the Late Triassic tectonism in the northern Sanjiang region. In order to delineate the tectonic setting and evolutionary process of the paleo arc-basin system, geochemical studies on the Batang Group strata have been carried out. The results suggest that andesite in the Zhaokalong area mainly belongs to the tholeiite series and is characterized by obvious fractionation of LREE and HREE, enrichment in LILE and depletion in HFSE, and a distinctly elevated δ^(34)SCDT average of 10.5‰. The sandstone is classified as lithic sandstone, which is also characterized by obvious fractionation of LREE and HREE, as well as weak negative Ce and Eu anomalies. The limestone displays positive Eu anomalies, with δ^(13)CPDB ranging from-1.3‰ to 4.4‰ and δ^(18) OSMOW ranging from 14.6‰ to 22.5‰. These results indicate that the andesite has a dual signature of both arc andesite and rift volcanic rocks, whereas the sandstone may be formed in an active continental margin, and the limestone could be deposited in a weak oxidizing shallow sea. The sandstone in the Zhaokalong area represents sedimentation in a platform slope facies, corresponding to the main stage of the Jinshajing oceanic basin subduction during the middle period of Late Triassic. The continental arc volcanic activity resulted from subsequent strengthened subduction, forming the andesite in the North Qiangtang backarc basin. Afterwards, the limestone was formed after the cessation of magmatic activity. The information gleaned from the Batang Group strata helped constrain the evolution of the paleo-Jomda island arc and Jinshajiang oceanic subduction in the Late Triassic. | LI Huan XI Xiaoshuang SUN Huashan KONG Hua WU Qianhong WU Chengming Jillian Aira S.GABO-RATIO | 2016 | Acta Geologica Sinica(English Edition)2016，90，2： | 3 |
| 8 | Ore-forming Fluid Characteristics of the Saishitang Cu-polymetallic Deposit in Qinghai Province,China显示文摘Saishitang Cu-polymetallic deposit is located in the southeast section of Late Paleozoic arcfold in the southeastern margin of Qaidam platform. Accoring to the geological process of the deposit,four mineralization episodes were identified: melt/fluid coexisting period(O),skarn period(A),first sulfide period(B) and second sulfide period(C),and 10 stages were finally subdivided. Three types of inclusions were classified in seven stages,namely crystal bearing inclusions(type I),aqueous inclusions(type II) and pure liquid inclusions(type III). Type I and II inclusions were observed in stage O1,having homogenization temperature from 252 to 431°C,and salinities ranging from 24.3% to 48.0%. Type I inclusion was present in stage A1,having homogenization temperature from 506 to 548°C,and salinities ranging from 39.4% to 44.6%. In stage B1,type II and III inclusions were observed,with homogenization temperature concentrating between 300–400°C,and salinities from 0.4% to 4.3%. Type II inclusions were present in stage B2,with homogenization temperature varying from 403 to 550°C. In stage C1,type I and II inclusion commonly coexisted,and constituted a boiling inclusion group,having homogenization temperatures at 187–463°C,and salinities in a range of 29.4%–46.8% and 2.2%–11.0%. Type II and III inclusions were developed in stage C2,having homogenization temperature at 124–350°C,and salinities ranging between 1.6% and 15.4%. In stage C3,type II and III inclusions were presented,with a homogenization temperature range of 164–360°C,and salinities varying from 4.0% to 11.0%. The results of micro-thermal analysis show that fluids are characterized by high temperature and high salinity in stage O1 and A1,and experienced slight decrease in temperature and dramatic decrease in salinity in stage B1 and B2. In stage C1,the salinity of fluid increased greatly and a further decrease of temperature and salinity occurred in stage C2 and C3. Fluids boiled in stage C1. With calculated pressure of 22 MPa from the trapping temperature of 284–289°C,a mineralization depth of 2.2 km was inferred. Results of Laser Raman Spectroscopy show high density of H2 O,CH4 and CO2 were found as gas composition. H-O isotope study indicates the oreforming fluids were the mixture of magmatic water and meteoric water. Physicochemical parameters of fluids show oxygen and sulfur fugacity experienced a decrease,and redox state is weakly reducing. Along with fluid evolution,oxidation has increased slightly. Comprehensive analysis shows that melt exsolution occurred during the formation of quartz diorite and that metal elements existed and migrated in the form of chlorine complex. Immiscible fluid separation and boiling widely occurred after addition of new fluids,bringing about dissociation of chlorine-complex,resulting in a great deal of copper precipitation. In conclusion,Saishitang deposit,controlled by regional tectonics,is formed by metasomatism between highly fractionated mineralization rock body and wall rock,and belongs to banded skarn Cu-polymetallic deposit. | LAI Jianqing JU Peijiao MAO Yin AN Jianghua WANG Xiongjun | 2015 | Acta Geologica Sinica(English Edition)2015，89，2： | 2 |
| 9 | Ore-Forming Fluids Characteristics and Metallogenesis of the Anjing Hitam Pb-Zn Deposit in Northern Sumatra, Indonesia显示文摘The Anjing Hitam Pb-Zn deposit in northern Sumatra(Indonesia) is one of the largest Pb-Zn deposits in the region. The stratiform orebodies are mainly hosted in the middle member of the Carboniferous–Permian Kluet Formation of the Tapanuli Group. Mineral paragenesis and crosscutting relationships suggest a two-stage Pb-Zn mineralization:(I) sedimentary and(Ⅱ) hydrothermal mineralization. Ore-related calcite from both stages Ⅰ and Ⅱ contains mainly liquid-and gas-liquid two-phase-type fluid inclusions(FI). For stage I ore-forming fluids, FI homogenization temperatures(T_h) are 105 to 199 oC, and the salinities are 9.6 wt.% to 16.6 wt.% NaCleqiv, reflecting low temperature and medium-low salinity; whereas in stage Ⅱ, the T_h(206 to 267 oC) and salinity(19.0 wt.% to 22.5 wt.% NaCleqiv) are considerably higher. Fluid inclusion and C-O isotope characteristics suggest that the stage I ore-forming fluids were mainly derived from a mixture of seawater and magmatic fluids(probably from deep-lying plutons), whereas the stage Ⅱ ore-forming fluids were likely magmatic-derived with wall rock input. We propose that the Anjing Hitam deposit was a Carboniferous exhalative sedimentary(SEDEX) deposit overprinted by the Pleistocene vein-style magmatic-hydrothermal mineralization. | Chaowen Huang Gaofeng Du Huajun Jiang Jianfeng Xie Daohan Zha Huan Li Chun-Kit Lai | 2019 | Journal of Earth Science2019，30，1： | 2 |
| 10 | Geological Characteristics and Genesis of the Jiamoshan MVT Pb–Zn Deposit in the Sanjiang belt, Tibetan Plateau显示文摘The carbonate-hosted Pb–Zn deposits in the Sanjiang metallogenic belt on the Tibetan Plateau are typical of MVT Pb–Zn deposits that form in thrust-fold belts. The Jiamoshan Pb–Zn deposit is located in the Changdu area in the middle part of the Sanjiang belt, and it represents a new style of MVT deposit that was controlled by karst structures in a thrust–fold system. Such a karst-controlled MVT Pb–Zn deposit in thrust settings has not previously been described in detail, and we therefore mapped the geology of the deposit and undertook a detailed study of its genesis. The karst structures that host the Jiamoshan deposit were formed in Triassic limestones along secondary reverse faults, and the orebodies have irregular tubular shapes. The main sulfide minerals are galena, sphalerite, and pyrite that occur in massive and lamellar form. The ore-forming fluids belonged to a Mg2+–Na+–K+–SO2-4–Cl-–F-–NO-3–H2 O system at low temperatures(120–130°C) but with high salinities(19–22% NaCl eq.). We have recognized basinal brine as the source of the ore-forming fluids on the basis of their H–O isotopic compositions(-145‰ to-93‰ for δDV-SMOW and-2.22‰ to 13.00‰ for δ18 Ofluid), the ratios of Cl/Br(14–1196) and Na/Br(16–586) in the hydrothermal fluids, and the C–O isotopic compositions of calcite(-5.0‰ to 3.7‰ for δ13 CV-PDB and 15.1‰ to 22.3‰ for δ18 OV-SMOW). These fluids may have been derived from evaporated seawater trapped in marine strata at depth or from Paleogene–Neogene basins on the surface. The δ34 S values are low in the galena(-3.2‰ to 0.6‰) but high in the barite(27.1‰), indicating that the reduced sulfur came from gypsum in the regional Cenozoic basins and from sulfates in trapped paleo-seawater by bacterial sulfate reduction. The Pb isotopic compositions of the galena samples(18.3270–18.3482 for 206 Pb/204 Pb, 15.6345–15.6390 for 207 Pb/204 Pb, and 38.5503–38.5582 for 208 Pb/204 Pb) are similar to those of the regional Triassic volcanic-arc rocks that formed during the closure of the Paleo-Tethys, indicating these arc rocks were the source of the metals in the deposit. Taking into account our new observations and data, as well as regional Pb–Zn metallogenic processes, we present here a new model for MVT deposits controlled by karst structures in thrust–fold systems. | LIU Yingchao YANG Zhusen YUE Longlong YU Yushuai MA Wang TANG Bolang | 2020 | Acta Geologica Sinica(English Edition)2020，94，4： | 2 |
| 11 | Geologic,Fluid Inclusion and Stable Isotope Constraints on Mechanisms of Ore Deposition at the Datuanshan Copper Deposit,Middle-Lower Yangtze Valley,Eastern China显示文摘The Datuanshan deposit is one of the largest and most representative stratabound copper deposits in the Tongling area,the largest ore district in the Middle-Lower Yangtze River metallogenic belt.The location of the orebodies is controlled by the interlayer-slipping faults between the Triassic and Permian strata,and all the orebodies are distributed in stratiform shape around the Mesozoic quartz monzodiorite dikes.Based on field evidence and petrographic observations,four mineralization stages in the Datuanshan deposit have been identified:the skarn,early quartz-sulfide,late quartzsulfide and carbonate stages.Chalcopytite is the main copper mineral and mainly formed at the late quartz-sulfide stage.Fluid inclusions at different stages were studied for petrography,microthermometry,laser Raman spectrometry and stable isotopes.Four types of fluid inclusions,including three-phase fluid inclusions(type 1),liquid-rich fluid inclusions(type 2),vapour-rich fluid inclusions(type 3) and pure vapour fluid inclusions(type 4),were observed.The minerals from the skarn,early and late quartz-sulfide stages contain all fluid inclusion types,but only type 2 fluid inclusions were observed at the carbonate stage.Petrographic observations suggest that most of the inclusions studied in this paper are likely primary.The coexistence of different types of fluid inclusions with contrasting homogenization characteristics(to the liquid and vapour phase,respectively) and similar homogenization temperatures(the modes are 440-480℃,380-400℃ and 280-320℃ for the skarn,early and late quartz-sulfide stages,respectively) in the first three stages,strongly suggests that three episodes of fluid boiling occurred during these stages,which is supported by the hydrogen isotope data.Laser Raman spectra identified CH_4 at the skarn and early quartz-sulfide stages.Combined with other geological features,the early ore-forming fluids were inferred to be under a relatively reduced environment.The CO_2 component has been identified at the late quartz-sulfide and carbonate stages,indicating that the late ore-forming fluids were under a relatively oxidized environment,probably as a result of inflow of and mixing with meteoric water.In addition,microthermometric results of fluid inclusions and H-O isotope data mdicate that the ore forming fluids were dominated by magmatic water in the early stages(skarn and early quartz-sulfide stages) and mixed with meteoric water in the late stages(late quartz-sulfide and carbonate stages).The evidence listed above suggests that the chalcopyrite deposition in the Datuanshan deposit probably resulted from the combination of multiepisode fluid boiling and mixing of magmatic and meteoric water. | CAO Yi DU Yangsong PANG Zhenshan DU Yilun KOU Shaolei CHEN Linjie GAO Fuping ZHOU Guibi | 2015 | Acta Geologica Sinica(English Edition)2015，89，3： | 2 |
| 12 | Growth Pattern and Its Indication of Spheroidal Nano-Micro Crystal Aggregates of Pyrite in the Baiyunpu Pb-Zn Polymetallic Deposit, Central Hunan显示文摘The Baiyunpu deposit lies in the southwest plunging Dachengshan anticline in central Hunan, which is a large Pb-Zn polymetallic deposit. The orebodies were surrounded by the Qiziqiao Formation limestone in the Middle Devonian, and its geological occurrence is consistent with the wall rocks. A large number of spheroidal pyrite aggregates are found unevenly distributed in the ores. The spheroidal aggregates are made up of kernels and concentric rings. The kernels are composed of approximately epigranular pyrite nanocrystals, while the rings are composed of accumulated pyrite microcrystals growing along the radial direction. The spheroidal pyrite aggregate and its outer zones can be divided into five areas(A–E). The results of electron probe micro analysis(EPMA) show that from the zone A1 to B, Co/Ni <1, the sum of Co and Ni is 0.08%–0.26%, S/Fe increases from 2.06 to 2.15. While from the zone C to E, Ni cannot be detected and S/Fe decreases from 2.22 to 2.08. Powder X-ray diffraction(XRD) analysis in the micro zone shows obvious crystalline characteristics in the aggregates. Moving from the inside outwards, the maximum diffraction peak intensity of the(111) and(220) crystal planes of pyrite increases, and the crystallinity improves. The degree of change in the(111) plane is the most prominent. Considering the theory of crystal growth along with the geologic features of the depositional environment where the spheroidal pyrite aggregates developed, we confirm that the spheroidal aggregates are the result of nano-micro crystalline gathering and growth occurring by the following sequence of processes:nano-crystalline nucleation and growth, gathering into a ball, oriented growth of microcrystals, continuous accumulation, and adjustment of grain boundaries. The formation of the spheroidal pyrite aggregates in the late Qiziqiao Formation of the Middle Devonian occurred in a neutral to weak alkaline and reductive sedimentary environment in the normal oxygen-rich shallowwater carbonate platform edge. The variations in the S/Fe ratio and crystallisation characteristics indicate that during pyrite crystal growth, the sulphur fugacity was high locally and rose constantly, the degree of supersaturation decreased locally and the growth environment was stable relatively. | GAO Shang HUANG Fei GU Xiangping LI Xiangyou MENG Lin LIU Rui SUN Li GAO Wenyuan YU Huantao | 2014 | Acta Geologica Sinica(English Edition)2014，88，6： | 2 |
| 13 | Genesis of the Binh Do Pb-Zn Deposit in Northern Vietnam:Evidence from H-O-S-Pb Isotope Geochemistry显示文摘The Binh Do Pb-Zn deposit in the Phu Luong region(Thai Nguyen Province,northern Vietnam)is located on the southern margin of the South China Block.The fault-controlled Pb-Zn orebodies are mainly hosted in Upper Paleozoic carbonate formations.In order to reveal the mineralization type and metallogenesis of this deposit,multi-isotopic(S,Pb,H and O)analyses on typical ore and gangue minerals were conducted.The average ore sulfide δ^34 S∑S value is 4.3‰,suggestive of magmatic sulfur.The ore sulfide Pb isotope compositions are homogeneous,with the 206 Pb^204 Pb,207 Pb^204 Pb and 208 Pb^204 Pb values of 18.501 to 18.673,15.707 to 15.798,and 38.911 to 39.428,respectively.Lead isotope model ages of the ore sulfides(240-220 Ma)are consistent with the timing of regional Triassic S-type granite emplacement(250-220 Ma),suggesting that the metals may have been granite-derived.The quartz δDV-SMOW(-82.4‰ to-70.5‰)and δ^18 OH2 O(-0.4‰ to +6.4‰)values suggest that the ore-forming fluids were composed of mixed magmatic and meteoric waters.Combined with the geological features of the Pb-Zn deposit in the region,we propose that the Pb-Zn deposits belong to magmatic-hydrothermal type,rather than MVT-type as previously suggested.The Triassic granites may have contributed the ore-forming material and heat that drove the hydrothermal system.The ore-forming fluids may have migrated into interlayer faults and fractures of the carbonate strata,diluted by subsurface meteoric water and deposited successively the vein-type and stratiform-type Pb-Zn ores. | Chaowen Huang Huan Li Chun-Kit Lai | 2019 | Journal of Earth Science2019，30，4： | 1 |
| 14 | 中国西南地区含铅锌矿化兰坪盆地中石膏层的盐结构和来源显示文摘兰坪盆地广泛分布着大规模的石膏层和世界级的铅锌矿床。本研究结合野外调查和地球化学分析结果以确定本区石膏的来源和演化过程。兰坪盆地石膏层序发育于三叠系三河洞组和古近系云龙组两个地层。前者为原生厚条带状结构,δ34SV-CDT值在14.5‰~14.8‰。结合灰岩87Sr/86Sr比值(0.707737~0.707783),本文认为三河洞组为海相成因。相反,古近系云龙组石膏具有穹隆、珠状和底辟盐构造特征,87Sr/86Sr(0.707695~0.708629)和δ34SV-CDT值(9.6‰~17‰)的区间较宽,表明其为海相来源,但也有陆相物质的输入。最初的层状盐层是在盆地中以化学沉积的形式形成的,后来的多种形貌不同的盐结构是在喜马拉雅期受到碰撞造山作用的影响,发生强烈变形而形成的。在此基础上,构建了一个解释兰坪盆地石膏建造成因的演化模式。 | 张治波 朱志军 李欢 蒋维诚 王文峰 徐颖 李丽荣 | 2020 | Journal of Central South University2020，27，6： | 1 |
| 15 | Determining Fluid Compositions in the H_2O-NaCl-CaCl_2 System with Cryogenic Raman Spectroscopy:Application to Natural Fluid Inclusions显示文摘Previous cryogenic Raman spectroscopic analysis of H_2O-NaCl-CaCl_2 solutions has identified the Raman peaks of various hydrates of NaCl and CaCl_2,and established a linear relationship between Raman band intensity of the hydrates and the composition of the solution(NaCl/(NaCl+CaCl_2) molar ratio,or X_(NaC1)) using synthetic fluids,which created the opportunity to quantitatively determine the solute composition of aqueous fluid inclusions with cryogenic Raman spectroscopy.This paper aims to test the feasibility of this newly established method with natural fluid inclusions.Twenty-five fluid inclusions in quartz from various occurrences which show a high degree of freezing during the cooling processes were carefully chosen for cryogenic Raman analysis.X_(Na)Cl was calculated using their spectra and an equation established in a previous study.These inclusions were then analyzed with the thermal decrepitation-SEM-EDS method.The X_(NaCl) values estimated from the two methods show a 1:1 correlation,indicating that the new,non-destructive cryogenic Raman spectroscopic analysis method can indeed be used for fluid inclusion compositional study. | CHU Haixia CHI Guoxiang | 2015 | Acta Geologica Sinica(English Edition)2015，89，3： | 1 |
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