Mineralogy and textural relationships among sulphosalts and related minerals in the Bleikvassli Zn-Pb-(Cu) deposit, Nordland, Norway

Several distinct assemblages of Pb-Sb, Pb-As, Cu-Pb-Sb and Cu-Fe-Zn-Sn sulphosalts are identified in sulphide samples from Bleikvassli mine, Norway. Detailed optical microscopy and electron probe microanalysis have permitted investigation of textural relationships between minerals and compositional variations between different ore types. Tetrahedrite, typically containing 10–16?wt.% Ag (rare freibergite containing 25–30?wt.% Ag has also been identified in two samples), stannite (Cu₂(Fe>Zn)SnS₄), and meneghinite, CuPb₁₃Sb₇S₂₄, are widely distributed as trace constituents throughout massive pyritic and galena-rich ores. Native antimony and pyrargyrite occur in trace amounts in all ore types, as the breakdown products of earlier sulphosalts. Several distinct types of wall-rock mineralisation are present at Bleikvassli. Of considerable mineralogical interest are the coarse-grained sulphide mobilisates within the wall rock which contain a distinct?and characteristic suite of Pb-As sulphosalts:?tennantite?+?jordanite (Pb₁₄As₆S₂₃)?+?seligmannite (CuPbAsS₃) ± dufrenoysite (Pb₂As₂S₅). Bournonite (CuPbSbS₃) is the only Sb-bearing sulphosalt recognised in significant amounts within the mobilisates, meneghinite and tetrahedrite being conspicuously absent. These mobilisates display considerable Au enrichment; electrum can be confirmed, intimately associated with jordanite and tennantite. Appreciable Sb (up to 3?wt.%) is contained within galena in the mobilisates, in contrast to galena from massive ores which contains only negligible Sb. Contents of Ag and Bi in galena vary considerably in all ore types, but confirm earlier suggestions that galena is a major Ag-carrier at Bleikvassli. Boulangerite (Pb₅Sb₄S₁₁), jamesonite (FePb₄Sb₆S₁₄) and gudmundite (FeSbS) occur in trace amounts. Sn-sulphosalts are represented by kësterite, (Cu₂(Zn> Fe)SnS₄), but commonly zoned with respect to Zn/Fe ratio, in the mobilisates, rather than by stannite. A rare type of mobilisate, also in the wall rock, in which chalcocite and bornite are the main minerals, contains native Ag, stromeyerite (AgCuS), mckinstryite ((Ag,Cu)₂?S), Ag-free tetrahedrite, an unnamed Cu-Ag-Fe sulphide (Cu₃Ag₂FeS₄) and native Bi, myrmekitically intergrown with chalcocite. Although a comprehensive genetic model for the wall-rock mineralisation at Bleikvassli is largely impossible given the limitations in the present state of knowledge regarding mechanisms involved in remobilisation processes, a multi-stage model of remobilisation during regional metamorphism is considered to best explain the observations. An interplay of different solid- and liquid-state remobilisation mechanisms, in various combinations, is required to account for the macro- and microscopic observations. Remobilisation probably began during the earlier stages of metamorphism, with crystallisation and further remobilisation taking place during the entire metamorphic cycle, giving rise to the extensive chemical and mineralogical diversity observed today. Preserved mineral assemblages and their textural relationships reflect a complex sequence of replacement and decomposition reactions taking place during the latest phase of late-metamorphic crystallisation and subsequent cooling.     

A sulphur isotopic study of the Bleikvassli Zn-Pb-Cu deposit,Nordland, northern Norway

The Bleikvassli Zn-Pb-Cu deposit occurs in the Uppermost Allochthon in the Caledonides of northern Norway. The orebody is enclosed in amphibolite-facies schists and gneisses, underlain by amphibolites, and it has been classified as a sediment-hosted massive sulphide (SEDEX) deposit. The stratiform ore is dominantly pyritic, with a basal layer of pyrrhotitic ore. Sulphide veins occur in the footwall. The orebody generally has a limited range of ³⁴S, from 0.3 to 4.5% (x = 2.4 ± 1.2, 1 , n = 26). The lowest ³⁴S values (0.3–2.3) were found in sulphide veins in the footwall and vent proximal stratiform ore. More distal pyritic Zn-Pb ore has heavier average ³⁴S values (up to 4.5). The ore sulphides were deposited from a hydrothermal solution with ³⁴S about 2 perhaps with the incorporation of a minor portion of sulphide from the ambient seawater. The hydrothermal solution probably acquired most of its sulphide from the underlying mixed lithology; notably basaltic rocks. Sulphide produced by thermochemical reduction of seawater in the deep conduit system may also have been incorporated. Bacteriogenic sulphide is not likely as a major source of ore sulphur in the massive ore. Sulphide incorporated in distal pyrite, which have ³⁴S from -12 to-10, could have formed either by oxidation of the hydrothermal sulphide, or by bacterial reduction of seawater sulphate in the depositional environment. Exchange of sulphur isotopes probably took place only on a localized scale during Caledonian metamorphism, the bulk sulphur isotopic composition of the ore being preserved in a hand specimen scale.     

Lead-isotope study of the sulphide ore and alteration zone,Bleikvassli zinc-lead deposit,northern Norway

The Bleikvassli Zn-Pb deposit is located in the Uppermost Allochthon of the northern Norwegian Caledonides and is enclosed in amphibolite facies, multiply deformed supracrustal rocks. The stratiform orebody occurs stratigraphically above a sequence of gneiss and amphibolite and below a thick carbonate unit. The orebody, spatially associated with a footwall microcline gneiss that contains as much as 12wt K₂O, occurs in the lower part of the Mine Sequence which also comprises (kyanite-) mica schist and quartzo-feldspathic to siliceous rocks. The host rock lithology and the metal content of the Bleikvassli orebody are consistent with a SEDEX origin of the deposit. Field relationships and chemistry suggest that the microcline gneiss represents a potassic alteration of pelitic sediments related to the ore-forming process. A 464 ± 22 Ma Rb-Sr isochron for the microcline gneiss is interpreted to be a metamorphic age resulting from resetting of the Rb-Sr isotopic system during the Caledonian orogeny. The U-Pb in the whole rock shows evidence of recent mobilization of uranium and a partial or total resetting of the system during peak metamorphism. As with most SEDEX deposits, the lead isotope composition of the Bleikvassli ore plots close to the orogen growth curve. The geological setting of the ore and the lead — isotope compositions of the galenas indicate a Cambrian age of mineralization. However, the slope of the lead isotope data indicate an age of about 1000 Ma, which is also a maximum age of ore deposition. The lead isotope data for the galena, in conjunction with the compositions of the microcline gneiss during peak metamorphism, support a model whereby the microcline rock was formed as an alteration product by the ore forming fluid and the initial lead isotope composition of the microcline rock was similar to that of the galenas during ore deposition.     

Origin of tourmaline and oxide minerals from the metamorphosed Rampura Agucha Zn-Pb-(Ag) deposit, Rajasthan, India

Summary The sediment-hosted exhalative Rampura Agucha Zn-Pb-(Ag) deposit in Rajasthan, India, contains a number of oxide minerals which have been formed as a result of high-grade metamorphism. Gahnite (Zn_0.66–0.75Fe_0.13–0.24Mg_0.06–0.13Al_1.98–2.01O₄) is a common minor phase in the ores and formed from breakdown of sphalerite and Al-rich silicates. Pyrophanite-ilmenite solid solution (Fe_0.42–0.68Mn_0.32–0.58Ti_0.99–1.01O₃) is very rare and occurs, intergrown with rutile, as a result of unmixing of a Ti-Fe-Mn bearing precursor mineral.Dravite-rich tourmaline with Fe/(Fe+Mg) ratios around 0.02 occurs at the hanging wall contact of the orebody with the paragneisses and is intergrown with the ore minerals. Tourmaline from the stratabound ores is distinguished from schorl-rich tourmaline of two pegmatite samples which show Fe/(Fe+Mg) ratios of 0.43 and 0.62, respectively. It is argued that dravite-rich tourmaline (or another B-rich precursor mineral) is of premetamorphic origin. This dravite-rich tourmaline recrystallized during high-grade metamorphism when the metamorphic fluid, represented by H₂O-CO₂±CH₄-N₂ inclusions, was trapped.Amphiboles, muscovites and biotites from metamorphic rocks of the deposit display radiometric³⁹Ar/⁴⁰Ar cooling ages between 788 and 909 Ma.

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Dravit-reicher Turmalin und Oxide der metamorphen Zn-Pb-(Ag) Lagerstätte Rampura Agucha, Rajasthan, Indien

Zusammenfassung Die sedimentär-exhalative Zn-Pb-(Ag) Lagerstätte Rampura Agucha in Rajasthan, Indien, beinhaltet eine Reihe von Oxidmineralen, die infolge der hochgradigen Regional-metamorphose gebildet wurden. Gahnit (Zn_0.66–0.75Fe_0.13–0.24 Mg_0.06–0.13Al_1.98–2.01O₄) ist eine häufig anzutreffende Phase, die sich aus Sphalerit und Al-reichen Silikatphasen gebildet hat. Pyrophanit-Ilmenit (Fe_0.42–0.68Mn_0.32–0.58 T_0.99–1.01O₃) ist sehr selten und bildet, aufgrund der Entmischung eines Ti-Fe-Mn hältigen Vorläuferminerals, Verwachsungen mit Rutil.Dravit-reicher Turmalin mit einem Fe/(Fe+Mg) Verhältnis um 0.02 bildete sich gleichzeitig mit den Sulfidmineralen am Kontakt des Erzkörpers mit den hangenden Paragneisen der Lagerstätte. Dieser Turmalin unterscheidet sich klar von Schörlreichem Turmalin mit Fe/(Fe+Mg) Verhältnissen von 0.43 und 0.62 von zwei Pegmatiten. Die Herkunft dieses prämetamorphen Dravit-reichen Turmalins (oder dessen Vorgängerminerals) ist unklar. Dieser Turmalin rekristallisierte während der Metamorphose, wobei er das metamorphe H₂O-CO₂±CH₄-N₂-Fluid in Form von primären Einschlüssen einschloß.Amphibol, Muskowit und Biotit wurden mittels³⁹Ar/⁴⁰Ar-Methode datiert und liefern radiometrische Abkühlungsalter zwischen 788 und 909 Ma.

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云南毛坪铅锌（银、锗）矿床流体包裹体特征及成矿流体来源

云南毛坪铅锌（银、锗）矿床是川滇黔成矿域滇东北地区以碳酸盐岩为主岩的中-大型铅锌（银）矿床的典型代表。矿体空间分布严格受NE向层间断裂带和猫猫山倒转背斜的控制。主要脉石矿物（铁方解石、方解石及白云岩）中的流体包裹体发育,一般较小（3～15μm）,主要为纯液相和液相包裹体,常沿矿物结晶面密集成群展布。成矿流体属Na^＋-K^＋-Ca^2＋-Cl^--F^-型,流体包裹体均一温度为180—218℃,盐度为4．1wt％-9．5wt％NaCl,成矿压力为406×10^5～570×10^5Pa。在主要脉石矿物流体包裹体中,Na^＋／K^＋（1．54～4．53）与Cl^-／F^-（0．72～156．33）较高,而重晶石流体包裹体中Na＋／K^＋（0．32～8．36）与Cl^-／F^-（1、06～16．77）较低。成矿流体的（D为-23‰～-64‰,方铅矿、闪锌矿和黄铁矿中流体包体（^18OV-SMOW依次为0、3‰～6．2‰,-9．0‰-3．4‰和-6．8‰～-12．7‰。脉石矿物的（^13CV-PDB为～1．1‰～-3.7‰。以上信息更好地揭示了成矿流体是变质水、岩浆水和建造水混合的产物,它们与沉积作用、昆阳群基底的变质作用及岩浆热液作用有关。该矿床本身可能是富含铅、锌、银等成矿流体对流循环沿构造“贯入”而成。该矿床不同于典型的MVT型铅锌矿床,是一碳酸盐岩为主岩的铅锌多金属硫化物矿床。     

广东怀集藤铁铁(铜)矿床地质特征

藤铁铁(铜)矿床是产于连阳岩体南缘鱼鹿岩株内外接触带上的典型矽卡岩型矿床.矽卡岩铁(铜)矿体呈似层状、透镜状产出,共生铜矿体位于铁矿体之上下盘,伴生组分Cu、Sn、Bi可综合利用.总结了铁(铜)成矿受高硅高碱质富挥发组分岩体、钙镁碳酸盐围岩以及接触带构造和断裂带构造的控制规律,对指导区域铁铜的地质找矿具有实际应用意义.     

西藏多不杂铜（金）矿床环境地质特征

多不杂斑岩铜金矿地处西藏阿里地区改则县境内,位于改则县城北西方向约100km处。该矿床位于班公湖-怒江缝合带西段北缘,目前已经控制的铜资源量超过400万吨,品位0.46%~1.13%;金资源量超过110 t,品位0.15 ~0. 26g/t（祝向平等,2012）,是西藏继玉龙、驱龙斑岩铜矿后发现的又一个具超大型远景规模的斑岩型富金铜矿床（李光明等,2007）。由于矿床位于藏北高原,生态环境极其脆弱,因此,研究其环境特征有着极为重要的意义。     

Typical Geological Features of Rich Zn-Pb-(Ge-Ag) Deposits in Northeastern Yunnan, China

Please?refer?to?the?attachment(s)?for?more?details.     

黑龙江省多宝山斑岩型铜(钼)矿床成矿流体特征及演化

黑龙江省多宝山斑岩铜(钼)矿床位于小兴安岭西北部,是中亚-兴蒙造山带北东段最大的斑岩型铜(钼)矿床,矿体产于加里东期花岗闪长岩和中奥陶世多宝山组安山岩、凝灰岩中。铜矿化与绢英岩化关系密切,而钼矿化主要产于钾硅化带中。矿区内脉体广泛发育,从早到晚依次为:石英+钾长石脉、早阶段石英+辉钼矿脉、晚阶段石英+辉钼矿脉、石英+黄铜矿+黄铁矿脉、石英+黄铁矿脉和方解石+石英脉。脉石英中广泛发育流体包裹体,包括气液两相水溶液包裹体(W型)、纯气相包裹体(G型)、含CO2三相包裹体(C型)及含子矿物多相包裹体(S型)。石英+钾长石脉中仅发育气液两相包裹体,均一温度峰值﹥550℃、盐度为16.2%～18.1%NaCleqv;早阶段石英+辉钼矿脉中发育大量气液两相包裹体和含子矿物多相包裹体,并见少量含CO2三相包裹体,均一温度集中在350～450℃、盐度变化于1.1%～﹥65.3%NaCleqv;晚阶段石英+辉钼矿脉体发育大量含CO2三相包裹体和含子矿物多相包裹体,另有少量气液两相包裹体,均一温度集中在270～350℃、盐度为0.8%～42.4%NaCleqv;石英+黄铜矿+黄铁矿脉中发育丰富的气液两相包裹体,见少量含子矿物多相包裹体、含CO2三相包裹体和纯气相包裹体,均一温度峰值在230～330℃、盐度为0.8%～42.4%NaCleqv;石英+黄铁矿脉和方解石+石英脉中仅发育气液两相包裹体,均一温度变化于110～200℃、盐度为3.9%～8.4%NaCleqv。成矿流体在古深度4.1km左右,温度在230～450℃之间、压力在10～41MPa之间,发生了强烈的流体沸腾作用,大量CO2等气体从流体中释放出来,黄铜矿、斑铜矿和辉钼矿等巨量沉淀下来,形成了铜(钼)矿体。成矿流体总体上属H2O-CO2-NaCl体系,多期次的流体沸腾作用是该矿床的主要成矿机制。     

杉松岗钴(铜镍)矿床地质特征及找矿远景

杉松岗钴(铜镍)矿床产于古元古代裂谷海槽褶皱地带,是国内新近发现的新类型矿床.它赋存于老岭群富硼、碳粘土岩夹硅质岩建造之中.通过对矿床的地质、地球化学特征研究,初步认为该矿床受后期变质热波的强烈叠加作用,形成沉积变质热液叠加改造型矿床.同时阐述了该矿床地质特征及找矿远景.     

西藏拿若铜(金)矿床隐爆角砾岩锆石U-Pb年代学及地球化学特征

<正>1研究目的(Objective)拿若矿床位于班公湖—怒江成矿带西段,由斑岩型和隐爆角砾岩型矿体组成,现已探明铜资源量243万t,伴生金资源量87 t,达到超大型矿床规模。此次研究通过隐爆角砾岩中岩体角砾与胶结物的锆石U-Pb年代学和Hf同位素、金属硫化物S同位素,旨在探讨该隐爆角砾岩的成岩时代、岩浆与成矿物质的来源。2研究方法(Methods)锆石U-Pb测年和硫同位素测试在北京核工业测试中心完成,使用仪器为PE Nex ION 300等离子体质谱仪和Geolas 193准分子固体激光器;硫同位     

Vinciennite and Cu-excess tennantite from the Layo (Cu,Sn, As,Au) epithermal deposit (Southern Peru)

Summary The Layo epithermal deposit, cutting Miocene-Pliocene calc-alkaline volcanites of the Tacaza group, includes a well-developed eastern zone (Vetas 7 and 8) in which brecciated and banded textures are associated with a large, intensely argillized zone containing diaspore and alunite. The vetas contain a typical Cu-As mineralogy of the acid-sulfate type (pyrite, enargite, Cu-excess tennantite, chalcopyrite, covellite) with an associated original stanniferous paragenesis including vinciennite and mawsonite. The vinciennite is close to the ideal end-member (Cu₁₀Fe₄SnAsS₁₆) and the Cu-excess tennantite (Cu₁₁FeAs₄S₁₃) shows a total absence of Zn and Ag; its very specific chemical composition suggests that all the iron is Fe³⁺, equilibrated by Cu⁺ and probably minor Cu²⁺.This particular mineralogical association implies deposition at relatively low temperature (300°C) and high aS₂ (10^–6.5 decreasing to 10^–8.5), from a Cu-S-rich and Fe-Zn-poor fluid. The acid-sulfate epithermal mineralization of the eastern vetas of Layo appears to have preceded an adularia-sericite epithermal mineralization expressed in the western vetas of Layo and also in the nearby large epithermal veins at Orcopampa and Shila. It also supports the genetic relationship that is commonly evoked between porphyry copper and epithermal deposits.

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Le minéralogie originale à vinciente et tennantite riche du gisement épithermal (Cu, Sn, As, Au) de Layo (Sud Péru)

Résumé Le gîte épithermal de Layo est encaissé dans les volcanites calco-alcalines Miocène-Pliocène du groupe de Tacaza. Sa zone orientale renferme des corps minéralisés (Vetas 7 et 8) bien développés, à textures bréchiques et rubanées associées à une large zone intensément argilisée contenant diaspore et alunite.Les vetas présentent une association minéralogique à As-Cu typique des gisements acide-sulfate (pyrite, énargite, tennantite riche en cuivre, chalcopyrite, covellite) et une paragenèse stannifère originale renfermant vinciennite et mawsonite. La vinciennite est proche du pôle théorique (Cu₁₀Fe₄SnAsS₁₆) et la tennantite riche en Cu (Cu₁₁FeAs₄S₁₃) est dépourvue de Zn et de Ag; sa composition chimique suggère que tout le fer se présente sous la forme Fe³⁺, en équilibre avec Cu⁺, avec probablement une participation mineure de Cu²⁺.Cette association minéralogique particulière implique une mise en place sous forte fugacité en soufre (aS₂ = 10^–6.5 décroissant jusqu'à 10^–8.5) à une température relativement basse de l'ordre de 300°C à partir d'un fluide riche en Cu et S et pauvre en Fe et Zn. La minéralisation de type acide-sulfate des vetas orientales de Layo précéderait celles de type adulaire-sericite des vetas occidentales de Layo et des gisements voisins de Orcopampa et Shila. Elle contribue à renforcer le lien fréquemment évoqué entre les porphyres cuprifères et les gisements épithermaux.

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西藏铁格隆南超大型铜(金、银)矿床地质、蚀变与矿化

铁格隆南是班公湖-怒江成矿带西段重要的斑岩-浅成低温热液铜(金、银)矿床,也是西藏地区首个铜资源量超过1000万吨的超大型铜(金、银)矿床,其蚀变与矿化结构的精细解剖,对完善区域成矿理论和指导找矿实践有重要的指导意义。文章基于详细的野外地质调查、钻孔编录和镜下鉴定,识别出铁格隆南矿床具有斑岩和浅成低温热液叠加成矿作用特征。其中,斑岩成矿作用主要位于矿床深部及外围,以细脉状、脉状、浸染状黄铁矿、黄铜矿、斑铜矿及少量辉钼矿等为主,蚀变为钾硅化、青磐岩化、黄铁绢英岩化,发育A、B、D型脉体。浅成低温热液成矿作用主要产于矿床中-浅部,叠加于斑岩成矿作用之上,以浸染状-脉状黄铁矿、硫砷铜矿、斑铜矿、铜蓝、蓝辉铜矿、斯硫铜矿、雅硫铜矿、久辉铜矿等Cu-S体系矿物为特征,蚀变为高级泥化,广泛发育N脉(即高岭石或明矾石-硫化物脉)。蚀变、矿化特征及脉体穿切关系揭示,矿床成岩成矿作用可细分为岩浆期(Ⅰ)、岩浆-热液期(Ⅱ)和表生期(Ⅲ)。成岩成矿年代学结果揭示,矿区内闪长玢岩侵位时代较早(123 Ma),代表岩浆活动上限;花岗闪长斑岩(122～120 Ma)是主要的含矿斑岩,与成矿作用关系最为密切;火山岩覆盖于地表,喷发时代较晚(111 Ma),代表成矿后岩浆活动的产物。钾硅化的黑云母和黄铁绢英岩化的绢云母40Ar-39Ar年龄分别(121.1±0.5) Ma、(120.8±0.9)Ma与斑岩成矿作用的辉钼矿Re-Os年龄((121.2±1.2) Ma)一致,而高级泥化的明矾石40Ar-39Ar年龄为(117.9±1.6)Ma与浅成低温热液矿化的黄铁矿Rb-Sr年龄((117.5±1.8)Ma)一致。所以,依据时空关系,铁格隆南超大型矿床成矿作用可细分为岩浆热液成矿作用(123～119 Ma)、浅成低温热液成矿作用(118～117 Ma)和火山岩覆盖保存(111～110 Ma)3个阶段。     

新疆鄯善县阿奇山铅锌（铜）矿床地质地球化学与成因探讨

新疆鄯善阿奇山铅锌(铜)矿位于东天山造山带西南缘。为探讨其矿床成因,在分析矿区地质特征的基础上,对矿体、矿石、典型矿物、蚀变分带及矽卡岩等进行了研究。结合成矿阶段划分、物质来源、同位素分析及小东山花岗斑岩锆石U-Pb定年数据,表明成矿与区内同源幔源岩浆作用及早石炭世雅满苏组矿源层关系密切,早石炭世花岗斑岩(331.5±2.0Ma)引起了雅满苏矿源层元素初始活化、局部富集,并提供了部分矿质,后期叠加了与小东山火山机构有关的受近东西向断裂构造控制的火山期后热液-交代充填成矿过程。综合上述信息,认为矿床受断裂构造控制,是与幔源岩浆岩有关的火山沉积-热液叠加改造型铅锌矿床。     

新疆西准噶尔宏远钼矿床和吐克吐克钼铜矿床流体包裹体特征及成矿时代

宏远（铜）钼矿和吐克吐克钼铜矿为新疆西准噶尔地区新发现的斑岩型矿床。流体包裹体测温和激光拉曼探针分析研究表明,宏远（铜）钼矿发育气液、气体和含子矿物包裹体等3类包裹体,气液比变化大,均一温度集中在140 ℃～200 ℃和260 ℃～340 ℃两个区间,吐克吐克钼铜矿只含有气液和含子矿物两类包裹体,气液比变化小,均一温度集中在180 ℃～220 ℃。两个矿区均发育高盐度和低盐度的NaCl-H₂O-CH₄-CO₂流体,显示含甲烷还原性流体的性质。宏远（铜）钼矿辉钼矿Re-Os同位素分析表明其成矿年龄为314.3±1.9 Ma,与西准噶尔包古图斑岩铜矿成矿时代一致。     

西藏多龙矿集区地堡那木岗铜(金)矿床流体包裹体特征及矿床成因

地堡那木岗铜(金)矿床位于西藏多龙矿集区,探明储量达大型规模;矿床的成矿过程分为岩浆作用阶段、钾长石-硫化物阶段、石英-多金属硫化物阶段、碳酸盐-黄铁矿阶段和氧化作用阶段,其中石英-多金属硫化物阶段和碳酸盐-黄铁矿阶段为主要成矿阶段;为查明成矿流体特征,确定矿床成因类型,对取自深部矿石中的碳酸盐脉(均为碳酸盐-黄铁矿成矿阶段含黄铁矿黄铜矿石英脉)开展流体包裹体的岩相学观察和显微测温分析。分析结果表明,上述矿物中主要发育富液相、富气相和含子矿物三相包裹体。其中,富液相包裹体的均一温度与盐度分别为:t=80~600℃、w(NaCl,eq)=4.48%~18.79%;富气相包裹体的均一温度和盐度分别为:t=240~560℃、w(NaCl,eq)=5.09%~9.73%;含子矿物三相包裹体的均一温度与盐度分别为:t=240~560℃、w(NaCl,eq)=36%~72%。综合分析认为,地堡那木岗铜(金)矿床成矿流体发生了强烈的沸腾作用,流体沸腾作用是该矿床的重要成矿机制。通过与国内外典型斑岩型矿床与高硫化型浅成低温热液矿床的流体包裹体特征进行对比,其与斑岩型矿床的中高温、高盐度流体特征相似。因此,推测地堡那木岗矿床的成因类型为斑岩型铜(金)矿床。     

西藏驱龙斑岩铜矿铜同位素研究

本文通过Cu的同位素组成示踪斑岩型铜矿床Cu的来源,探讨岩浆-热液过程中Cu同位素的分馏.选择驱龙矿区从早到晚的三期热液脉以及早期钾硅酸盐化蚀变同期的样品,挑选新鲜的黄铜矿,测定其Cu同位素组成.早期A脉:为不规则石英-钾长石脉、石英-硬石膏脉及黑云母脉,δ~(65)Cu的范围为-0.44‰～-0.09‰,集中在-0.44‰～-0.31‰,平均值-0.29‰;B脉,为石英+硬石膏+黄铜矿±辉钼矿±黄铁矿脉和绿帘石-石英脉,δ~(65)Cu的范围为-0.42‰～+0.14‰,集中在-0.25‰～-0.18‰,平均值-0.18‰;晚期D脉,为板状黄铜矿-黄铁矿及黄铁矿脉,δ~(65)Cu的范围为-0.27‰～+0.47‰,集中在-0.27‰～-0.05‰,平均值-0.02‰;早期钾硅酸盐蚀变带,δ~(65)Cu的范围为-0.47‰～-0. 1‰,平均值-0.29‰.矿区铜同位素组成基本同岩浆岩一致(Zhu et al.,2000,2002;Maréchal et al.,1999,2002),表明Cu主要来自斑岩岩浆.不同期次热液的Cu同位素具有明显的分馏,早期相对富集~(63)Cu,晚期相对亏损~(63)Cu,A脉与B脉的同位素组成的差异可能与岩浆-热液演化过程有关,D脉的同位素组成差异可能是大气降水大量混入的结果.     

Tectono-Chemistry for the Exploration of Concealed Orebodies of the Zhaotong Maoping Zn-Pb-(Ge-Ag) Deposit in Northeastern Yunnan, China

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珲春农坪金（铜）矿床地质特征及成因机制

农坪金（铜）矿床受控于东西向断裂构造带,产于英云闪长（斑）岩蚀变岩中,与闪长玢岩密切相关。矿床成因类型为次火山热液含金慢变岩型。矿床类型特殊,外围找矿潜力较大,对珲春地区金、铜找矿具有指导意义。