A tale of elemental accumulation and recycling in the metamorphosed Keketale VMS-type Pb-Zn deposit,Altai Mountains

The elemental accumulation and recycling in the metamorphosed Keketale VMS-type Pb-Zn deposit of the Altai Mountains are presented in this study. Based on detailed fieldwork and microscopic observation, the formation of the deposit involved syngenetic massive sulfide mineralization and epigenetic superimposed mineralization. Different generations of iron sulfides (i.e., pyrite and pyrrhotite) with contrasting textural, elemental, and sulfur isotopic features were generated in primary mineralization (including hydrothermal iron sulfides, colloform pyrite) and secondary modification (including annealed iron sulfides, oriented iron sulfides, and vein-pyrite). It is revealed that the spatial variation in textures and elements of hydrothermal iron sulfides depends on the inhomogeneous fluid compositions and varied environment in VMS hydrothermal system. Both leached sulfur from the footwall volcanic rocks and reduced sulfur by the TSR process are regarded as important sulfur sources. Furthermore, large sulfur isotopic fractionation and negative δ³⁴S values were mainly caused by varied oxygen fugacity, and to a lesser extent, temperature fluctuation. The epigenetic polymetallic veins that contain sulfides and sulfosalts (e.g., jordanite-geocronite, bournonite-seligmannite, boulangerite) were considered as the products of metamorphic fluid scavenged the metal-rich strata. All things considered, it is indicated that two episodes of fluid with distinct origins were essential for the formation of the deposit. The predominant evolved seawater along with subordinate magmatic fluid mobilized metals from volcanic rocks and precipitated massive sulfides near the seafloor are vital for primary mineralization. The metamorphic fluid remobilized metals (i.e., FMEs: fluid mobile elements, e.g., Pb, As, Sb) from neighboring volcanic and pyroclastic rocks and destabilized them within the fractured zone are responsible for secondary mineralization, which enhances the economic value of the deposit. Accordingly, metal-rich Devonian strata had been successively swept by different origins of fluid, leading to progressively elemental enrichment and the formation of a large deposit. Furthermore, the current study enlightens that FME-bearing veins with economic benefits can be discovered near the metamorphosed VMS deposits.     

黑龙江宁安英城子金矿床的地质、流体包裹体特征与成因研究

英城子金矿床是典型的浅成热液型矿床,为确定矿床成矿条件,结合矿床地质特征同时对不同深度的同一条含金石英脉中的流体包裹体分别进行了显微测温和激光拉曼光谱的分析研究。研究结果表明:英城子金矿床矿石类型主要为蚀变岩型,其次为石英脉型;成矿过程分为以下4个阶段:(Ⅰ)石英-毒砂-黄铁矿阶段、(Ⅱ)石英-黄铁矿阶段、(Ⅲ)石英-多金属硫化物阶段、(Ⅳ)石英-硫化物阶段;流体包裹体的类型多数为气液两相,少数为气、液单相或三相包体,均一温度变化范围247.9℃~400.0℃,盐度[w(NaCl)]为3.15%~7.70%,成矿流体密度为0.65 g/cm3~0.87g/cm~3;结合包裹体激光拉曼光谱数据确定成矿流体属于中低温,中低盐度的CO_2-H_2O-NaCl体系;根据测温数据,该矿床的成矿压力为6~50 MPa、相应就位深度为0.11~0.65 km;由此可推测该矿床是与韧性变形作用有关的中温中压热液金矿床。结合前人有关成矿年代学的研究成果,可以进一步确认成矿作用发生在晚二叠世末亚洲洋壳俯冲作用晚期,且与陆内松嫩板块和佳木斯板块碰撞过程中构造体制的转换紧密相关。     

阿尔泰南缘克兰盆地的脉状金-铜矿化及其流体演化

阿尔泰山南缘泥盆纪克兰火山-沉积盆地蕴藏有丰富的VMS锌铅铜多金属矿床。自晚泥盆世至早二叠世末, 阿尔泰山南缘为NE-SW向强烈挤压的构造环境, VMS矿石受到变形变质改造,脉状金铜矿化发育。金(铜)石英脉主要有2种产状:(1)白色-灰白色(硫化物)顺层石英脉(QI), 产于韧脆性剪切带发育地段,呈细脉状或透镜状产于绿泥片岩、黑云片岩中;(2)斜切黄铁矿化蚀变岩、层状铅锌矿和变质岩产状的黄铜矿-黄铁矿石英脉(QII),与晚期的脆性构造有关。金(铜)石英脉的流体包裹体发育,按室温下相态特征有3类。第I类为含子矿物的高盐度包裹体(L-V-S型),子晶为NaCl, 有时为KCl,包裹体呈孤立或无序分布,代表变质早期流体特征。一般NaCl子晶先消失(210~357℃),包裹体的最终均一温度369~512℃,其捕获温度与变质相的相平衡计算温度相当,反映了变质早期中高温热液活动的特征。第II类是富CO₂ 包裹体,包括单相的碳质流体包裹体(L _CO2、L _CO2-CH4或L _CO2-N2)和两相富CO₂包裹体(L _CO2-L _H2O)2个亚类。碳质流体包裹体是常见类型,有时与L _CO2-L_H2O型伴生,在较晚期的黄铜矿-黄铁矿石英脉中表现为原生特征,而在较早的石英脉中常表现为次生特征。萨热阔布的碳质流体可分为纯CO₂包裹体和CO₂-CH₄体系包裹体,纯CO₂包裹体的固体CO₂熔化温度(T_m,CO2)为 -60~-56.5℃,CO₂部分均一温度(T_h,CO2) 变化于-23~+31℃;密度一般为0.85~0.89g·m^-3。CO₂-CH₄包裹体的T_m,CO2＜-57℃,可低达-78.1℃,T_h,CO2低达-33.7~-17.7℃, 其密度高达1.01~1.07g·m^-3。VMS矿床中晚期叠加的黄铜矿石英脉中碳质流体包裹体可分为贫CH₄-N₂和富CH₄-N₂的CO₂-CH₄-N₂包裹体,贫CH₄-N₂的碳质包裹体T_m,CO2=-63.3~-57℃,T_h,CO2=-27.5~+29.7℃;富CH₄-N₂的CO₂-CH₄-N₂包裹体T_m,CO2=-83.4~-65.5℃,T_h,CO2=-56.0~+16.9℃。铜金石英脉中与碳质流体共生的L_CO2-L_H2O型包裹体均一温度T_h,total=205~370℃,略低于第I类高盐度包裹体的T_h,total=369~512℃。据CO₂流体高温高压相图估算包裹体的捕获压力至少为110~300MPa。金(铜)石英脉的主体在相当于445~566℃的高温条件下形成的,而金铜矿化则是在高于205~370℃、110~330MPa的中高温中深条件下发生的。流体包裹体的δ¹⁸O为7.54‰~11.84‰ (QI)和3.82‰~7.82‰ (QII), δD为-84.7‰~-98.2‰(QI)和-75.8‰~-108.8‰ (QII)。结合地质特征和流体研究,说明成矿热液来源与区域变质及相关的岩浆活动有关。     

The Xiaojiao high-grade eclogite-type rutile deposit in Jiangsu, China： Geology, geochemistry and metallogenesis

1INTRODUCTION TITANIUMMETALISPRODUCEDMAINLYFROMNATURAL RUTILEANDSYNTHETICRUTILEOBTAINEDBYENRICHEDILMEN ITE,ANDISWIDELYUSEDASHIGHTECHALLOYS,ESPECIALLY INTHEAIRANDSPACECRAFTINDUSTRYBECAUSEOFITSHIGH STRENGTHATHIGHTEMPERATUREANDRESISTANCETOCORRO SION.THEREISA…     

江西大吉山钨矿成矿年代学研究

大吉山钨矿床是一个大型的石英脉型钨矿床。矿床在空间上与燕山早期复式花岗岩相伴。利用云母单矿物的K Ar同位素年龄测试方法,测定了矿床有关的花岗岩及矿脉的同位素年龄。结果表明,黑云母花岗岩中黑云母K Ar年龄为(160 3±3 03)Ma和(164 2±3 5)Ma,二云母花岗岩中白云母K Ar年龄为(160 6±2 8)Ma,含钨石英脉中白云母K Ar年龄为(152 6±2 35)Ma和(158 1±2 8)Ma。钨成矿与花岗岩的成岩基本不存在时差,推测含钨石英脉的形成可能与岩浆分异出的富含矿化剂和成矿元素的流体有关。     

钠长岩类地质地球化学特征及变质变形与铜矿的形成——以四川会理拉拉铜矿床为例

本文论述了拉铜矿区钠长岩类的地质地球化学特征及变质变形与铜矿的形成,伴随前寒纪的构造运动,拉拉地区经历了NWW向的剪切变形,使钠长岩产生碎裂－糜棱岩化作用,形成碎裂结构,碎斑结构,显微眼球构造,压力影,云母鱼等,这些结构构造的形成使岩石孔隙度增加,起到找容作用,由沿近东西向主断裂侵位的辉绿辉长岩体提供的含矿流体及区域变质中产生的变质热变质热液沿钠长岩的碎裂－糜材构造充填交代,在其产生多种蚀变的同时,铜、钼、钴硫化物沉淀成矿,形成钠长岩型浸染状铜矿石或脉状－网脉状铜矿石。在金云母化较强地段,在变质作用下,形成片岩型铜矿石,因而总体上,拉拉铜矿属动力变质热液型铜矿床。     

新疆阿吾拉勒陆相火山岩型铜矿成矿研究

阿吾拉勒陆相火山岩型铜矿分为火山热液型、次火山热液型和中低温热液充填脉型，认为岩浆和成矿物质来源于深部地壳或上地幔，成矿与华力西晚期火山一次火山作用密切相关，铜矿是在同一构造环境下同一岩浆源分异演化不同阶段的产物。矿床成因属中低温火山一次火山热液成因。     

新疆东部金矿床类型、成矿特点及找矿方向

据金矿类型划分标准，结合新疆东部金成矿特点，划分出韧性剪切带型金矿、浅成低温热液型金矿、岩浆热液型金矿、斑岩型金（铜）矿、硅化帽型金矿及变质岩型或绿片岩型银金矿6种成因类型，8种工业类型。通过研究，划分出以斑岩型金矿为主的大南湖－三岔口成矿带、以韧性剪切带型金矿为主的康古尔塔格－黄山成矿带、以浅成低温热液型金矿为主的马庄山－南金山成矿带、以绿片蚀变岩型银金、铅锌矿以及硅铁建造型金矿为主的玉西－铅炉子成矿带、以岩浆热液型金矿为主的金窝子－照壁山成矿带和依热达坂－红山成矿带、以韧性剪切带型和硅帽型金矿为主的头苏泉－塔林成矿带7个金矿成矿带，在此基础上确定该区区找矿主要类型和远景区。     

安徽池州马头铜钼矿地质特征及蚀变分带

安徽池州马头铜钼矿是长江中下游成矿带中安庆—贵池矿集区内一个典型的铜钼矿床。通过野外地质祥查和系统的岩相学、矿相学工作,对该矿床的蚀变特征及分带进行了深入研究。识别出马头铜钼矿的蚀变类型主要有硅化、绢云母化、钾长石化,其次为黏土化、绿泥石化和碳酸盐化等。矿区围岩蚀变在空间上往往重叠,但具有一定的水平及垂向分带特征,自岩体深部至浅部、自内向外总体表现为面型石英钾长石化带、线型石英钾长石化带和石英绢云母化带。矿（化）体以脉状矿化为主,其中分布较广的石英脉带矿化主要产在石英绢云母化带中,以石英细（网）脉为主,受节理和裂隙控制;而品位较富的细脉浸染状矿化则主要产在面型钾长石化带中。通过研究认为,马头铜钼矿在成矿过程的早期阶段,由于高温、富钾和高pH值的热液流体作用,形成大面积的钾长石化,伴生与面型钾长石化有关的细脉、浸染状矿化;热液演化中期阶段,随着温度持续下降、K＋活度和流体pH值的降低,形成硅化、绢云母化等蚀变类型,并伴随范围较大的细脉-网脉状矿化;热液演化晚期阶段,主要形成碳酸盐化,而相应的矿化作用不显著。通过与部分典型斑岩型铜钼矿床的对比研究认为,马头铜钼矿在蚀变类型等方面与斑岩型铜钼矿大体相同,可归至斑岩型成矿体系。     

内蒙古中部召河庙地区金矿成矿规律及找矿预测

总结了召河庙地区金矿的成矿规律，指出本区所发现的具一定规模的金矿（化）点在区域上主要集 分布于青灰窑子－大井－程二沟－东柜一线，矿体均为含金石英脉。容矿岩系为新太古代变质石英闪长岩、斜长岩花岗岩。成矿物质来源主要为古老的变质中基性深成侵入岩，即所谓广义的绿岩带。矿源岩中金物质的活化受深断裂作用、韧性剪切作用、退变质作用、变质流体以及岩浆热液的多重影响，其中以构造作用和岩浆热液最为重要。金矿的形成时期较长，主成矿时期在元古代。预测程二沟－白音查干－东柜一带为今后进一步寻找金矿的优选靶区。     

Relative elemental mobility during hydrothermal alteration of a basic sill,Isle of Skye,N.W. Scotland

In Sconser quarry, Isle of Skye, a thin Tertiary basic sill is cut by vertical veins which formed fluid conduits in a major meteoric-hydrothermal system. In order to study the relative mobility of different elements during hydrothermal metamorphism, sill material adjacent to a large (6 mm wide) vein was cut into slices and subjected to geochemical and isotopic analysis. Isotopic evidence indicates that the basic magma which formed the sill was contaminated by Lewisian (Archaean) gneisses at depth, while material from Torridonian (Proterozoic) sandstone country rocks was introduced by hydrothermal fluids after crystallisation. The behaviour of the different elements during hydrothermal metamorphism divides them into 4 groups.

1. Large-ion low-charge elements Ba, K, Rb and Cs were strongly leached from the wall rock in the vicinity of the vein.
2. Other elements including Sr and Pb were depleted near the vein, but isotopic evidence indicates addition of some material from the fluids. This two-way nuclide transport forms an exchange process.
3. Many high-field-strength elements including the REE are slightly enriched near the vein, but Nd isotope evidence reveals no addition of material from fluids. These elements must have been relatively enriched by the removal of other elements (mainly Si and Al).
4. Ca and Na were added to the wall rock from fluid. The variable mobility of these elements is explained by the differing ease with which they could be incorporated into a new albite-calcite-chlorite-epidote mineralogy. The constitution of this hydrothermal mineralogy was largely determined by the primary igneous mineralogy, though the composition of hydrothermal fluids had a subordinate influence.

     

基于共生金属硫化物硫同位素分馏程度约束热液活动温度：以川中下寒武统龙王庙组为例

硫循环及硫同位素(δ³⁴S)分馏研究对地表圈层的成岩作用具有重要意义,其中多种金属硫化物中硫同位素的分馏程度可以约束成矿热流体温度,进而作为地温计证据约束热液活动。四川盆地龙王庙组储集层内的热液改造影响着该储集层的非均质性,本研究着重讨论目的层中与热液成因白云石所伴生的黄铁矿(FeS₂)-黄铜矿(CuFeS₂)成矿现象：基于详尽的岩石学证据,应用纳米二次离子探针(NanoSIMS)对金属硫化物内部硫同位素分布进行测定,并基于热力学驱动下的硫化物间平衡分馏程度计算其成矿温度,进而约束层段内热液活动过程。研究发现：(1)微区硫同位素分布显示黄铁矿(FeS₂)与黄铜矿(CuFeS₂)沉淀过程中不仅存在热力学分馏,还存在动力学分馏现象,其中动力学分馏程度可以达到40.1‰,应用NanoSIMS微区测定手段可以有效剔除动力学分馏数据影响,获取热力学平衡分馏数据;(2)黄铁矿(FeS₂)与黄铜矿(CuFeS₂)成矿过程或利用不同的硫源,其中黄铁矿...     

连山关地区下元古界中混合交代作用与铀成矿的关系

连山关地区在大地构造位置上,处于华北地台东北部营口—宽甸台隆与太子河台凹的过渡部位。前寒武纪地层在本区形成一短轴复背斜构造,轴向290°。背斜轴部由混合花岗杂岩体及呈残留体分布的鞍山群组成,四周为下元古辽河群所包围。背斜北翼有大面积上元古界及下古生界分布(图1)。近年来,在下元古界浪子山组底部与太古界基底混合杂岩体的不整合面附近发现了铀矿床。铀矿床主要赋存在浪子山组沉积变质岩及白色混合岩中。其形成     

柴北缘双口山金-银-铅矿床赋矿围岩及含金石英脉热液锆石U-Pb定年对成矿时代的限定及其成因启示

双口山金-银-铅矿床地处柴北缘西段,赋存在滩间山变基性-超基性变火山岩中。矿体由金矿体和银铅矿体组成,成矿作用与热液活动密切相关。本文通过对双口山含金矿体赋矿围岩及含金石英脉进行LA-ICP-MS锆石U-Pb年代学分析和研究。结果表明,赋矿围岩形成时代为443±2.9Ma,与区域滩间山群火山岩形成年代一致(440～490Ma)。含金石英脉热液锆石U-Pb年代为402.8±4.2Ma,与区域金矿床成矿年龄以及韧性剪切带年龄相接近(～400Ma),代表了金矿体热液作用及成矿时代。结合地质特征及前人研究,表明双口山金银铅矿床是柴北缘造山带在不同造山带演化阶段,由不同成矿作用,在不同时期,相互叠加形成的复合型多金属矿床。金矿体具有典型造山型金矿床特征的变质热液型金矿,其成因主要与造山运动过程中的变质和变形作用有关,成矿物质和流体来源于绿片岩相的滩间山群变基性-超基性变火山岩。银铅矿体为岩浆热液型,成矿与后碰撞造山作用伸展-构造转换有关的岩浆作用有关,成矿物质和流体来源于晚泥盆世深部含矿岩浆作用。     

关于热液岩

热液岩是指由热液（气水热液的总称）中结晶出来的矿物所组成的岩石。热液岩是在热液的形成过程中,或是在热液的运移过程中,萃取了先存岩石中的成分,并将其运移到了一定的空间（断裂的裂隙、褶皱的虚脱部位等）,由于热液的压力、温度、pH值及其他物理化学条件的变化,被热液萃取的某些组分从热液中结晶出来所组成的岩石。     

The mineralogy,sulfur-isotope composition and origin of some copper deposits in the Belt Supergroup,Southwest Alberta,Canada

Stratabound Cu mineralization in the Precambrian, red-bed sequences of the Belt-Purcell Supergroup of SW Alberta, Canada is described. Local enrichment of mineralization has been effected by younger Precambrian dioritic intrusions and by hydrothermal activity adjacent to normal faults. Data from mineralogic and sulfur isotope studies suggest that the base metal deposits were originally syngenetic or diagenetic and that they have suffered redistribution and concentration during contact metamorphism and perhaps low grade regional metamorphism. The primary metal-bearing fluids may have been derived by exhalative activity associated with a Precambrian aulacogenic structure which possibly underlies the region.     

Calcium-aluminum-silicate-hydrate “cement” phases and rare Ca-zeolite association at Colle Fabbri, Central Italy

Very high temperature, Ca-rich alkaline magma intruded an argillite formation at Colle Fabbri, Central Italy, producing cordierite-tridymite metamorphism in the country rocks. An intense Ba-rich sulphate-carbonate-alkaline hydrothermal plume produced a zone of mineralization several meters thick around the igneous body. Reaction of hydrothermal fluids with country rocks formed calcium-silicate-hydrate (CSH), i.e., tobermorite-afwillite-jennite; calcium-aluminum-silicate-hydrate (CASH) — “cement” phases - i.e., thaumasite, strätlingite and an ettringite-like phase and several different species of zeolites: chabazite-Ca, willhendersonite, gismon-dine, three phases bearing Ca with the same or perhaps lower symmetry of phillipsite-Ca, levyne-Ca and the Ca-rich analogue of merlinoite. In addition, apophyllite-(KF) and/or apophyllite-(KOH), Ca?Ba-carbonates, portlandite and sulphates were present. A new polymorph from the pyrrhotite group, containing three layers of sphalerite-type structure in the unit cell, is reported for the first time. Such a complex association is unique. Most of these minerals are specifically related to hydration processes of: (1) pyrometamorphic metacarbonate/metapelitic rocks (natural analogues of cement clinkers); (2) mineralization between intrusive stocks and slates; and (3) high-calcium, alkaline igneous rocks such as melilitites and foidites as well as carbonatites. The Colle Fabbri outcrop offers an opportunity to study in situ complex crystalline overgrowth and specific crystal chemistry in mineral phases formed in igneous to hydrothermal conditions.     

Submarine hydrothermal contribution for the extreme element accumulation during the early Cambrian,South China

Throughout the geological history of the Earth, submarine hydrothermal activity has played an important role in seawater chemistry, biological evolution and enrichment of metals in the Earth crust. However, the prospect of hydrothermal activity for extreme element accumulation during the early Cambrian, a key geological period, in South China has not been well-constrained. This study reports geochemical (e.g. REE and Sr isotope) investigations of a coarse-grained limestone layer and associated calcite veins in Zunyi and Nayong areas, Guizhou Province, to constrain the hydrothermal activity and evaluate the significance of hydrothermal contribution to extreme element accumulation during the early Cambrian, South China. Our results reveal positive Eu anomalies and higher initial ⁸⁷Sr/⁸⁶Sr ratios (0.7083–0.7150) for carbonate samples than those of early Cambrian seawater, indicating the presence of hydrothermal processes. Combined with constraints from the spatial relationships and coincidence with adjacent mineralization, these hydrothermal processes provide the most probable contribution for polymetallic Ni–Mo–PGE mineralization. Furthermore, there are abundant hydrothermal dolomite and barite-calcite veins in the dolostone of the Dengying Formation, indicating the occurrence of a variety of hydrothermal fluids. Overall, multi-stage hydrothermal pulses with different fluid compositions spanned the Ediacaran–Cambrian transition in South China. In particular, these hydrothermal fluids with positive Eu anomalies and enriched radiogenic Sr, originating from Proterozoic mafic/ultramafic rocks, may have flowed through the underlying Precambrian silicate clastic rocks (e.g., Xiajiang, Banxi and Lengjiaxi Groups) and may have been crucial for the marine environment, biological diversity and extreme element accumulation during the early Cambrian, South China.     

Trace element and REE geochemistry of Sanshenjiang gold deposit, southeastern Guizhou Province, China

The Sanshenjiang gold deposit in southeastern Guizhou Province, China, is hosted by the Neoproterozoic metasedimentary rocks which experienced low-grade greenschist facies metamorphism. Gold mineralization occurs mainly in the ribbon chiltern slate of the first member of the Longli Formation and is controlled by both strata and faults. Ore bodies are characterized by abundant quartz-arsenopyrite-gold-pyrite-bedding veins, veinlets and small lenses within the shear zone. In this study, trace element and REE geochemistry was analyzed to constrain the origin and genesis of this deposit. The trace element signatures of wall rocks and veins display a basically similar tendency in the spider diagram, showing the genetic relationship. The values of Co/Ni, Y/Ho, Hf/Sm, Nb/La and Th/La reflect that the hydrothermal fluids of this deposit were derived from the mixture of multiple sources with marked enrichment of Cl and moderate to high temperature. There is a broad similarity in the chondrite-normalized patterns and REE fractionation between wall rocks and ore bodies, possibly reflecting their similar origin. Based on the difference in δCe and δEu, quartz veins and lenses can be subdivided into weakly negative Ce-anomalies (δCe=0.81 to 1.06) with slight Eu anomalies (δEu=0.81 to 1.06) type and the significant positive Ce-anomalies (δCe=1.13 to 1.97) with moderate negative Eu-anomalies type, probably suggesting physical-chemical changes in the evolution process of ore-forming fluids from the early to late stage. It can be concluded that the ore-forming process may have experienced three stages: formation of the original ore source bed, regional metamorphism and gold mineralization, on the basis of trace element and REE analysis and field observation.     

Organic and inorganic geochemistry of Ljubija siderite deposits,NW Bosnia and Herzegovina

The Ljubija siderite deposits, hosted by a Carboniferous sedimentary complex within the Inner Dinarides, occur as stratabound replacement-type ore bodies in limestone blocks and as siderite–sulfides veins in shale. Three principal types of ore textures have been recognized including massive dark siderite and ankerite, siderite with zebra texture, and siderite veins. The ore and host rocks have been investigated by a combination of inorganic (major, trace, and rare earth element concentrations), organic (characterization of hydrocarbons including biomarkers), and stable isotope geochemical methods (isotope ratios of carbonates, sulfides, sulfates, kerogen, and individual hydrocarbons). New results indicate a marine origin of the host carbonates and a hydrothermal–metasomatic origin of the Fe mineralization. The differences in ore textures (e.g., massive siderite, zebra siderite) are attributed to physicochemical variations (e.g., changes in acidity, temperature, and/or salinity) of the mineralizing fluids and to the succession and intensity of replacement of host limestone. Vein siderite was formed by precipitation from hydrothermal fluids in the late stage of mineralization. The equilibrium fractionation of stable isotopes reveals higher formation temperatures for zebra siderites (around 245°C) then for siderite vein (around 185°C). Sulfur isotope ratios suggest Permian seawater or Permian evaporites as the main sulfur source. Fluid inclusion composition confirms a contribution of the Permian seawater to the mineralizing fluids and accord with a Permian mineralization age. Organic geochemistry data reflect mixing of hydrocarbons at the ore site and support the hydrothermal–metasomatic origin of the Ljubija iron deposits.