云南白秧坪矿化集中区矿石矿物特征及银、钴赋存状态的初步研究

云南白秧坪地区是以银、钴多金属矿化为特色的矿集区，成矿作用与兰坪盆地两侧的推覆构造系统密切相关，发育一套复杂的中低温热液矿物组合，出现了铜、钴、镍、铋等亲地幔元素的硫化物(硫钴镍矿、硫铋铜矿)，显示地幔深源物质可能参与了成矿作用。银、钴赋存状态的初步研究表明载银矿物主要为汞银矿、辉银矿、银黝铜矿、方铅矿、黝铜矿及砷、锑、铅硫盐矿物等，载钴矿物主要为硫钴镍矿、辉砷钴矿、含钴毒砂等硫化物。     

河南栾川赤土店西沟铅锌银矿床中银矿物的赋存状态及成矿机理探讨

为探讨西沟矿床的成矿物质来源、矿床成因和成矿金属元素赋存状态,本文利用电子探针分析技术,研究了该矿床中银的赋存状态,并探讨了银的成矿机理。结果表明,西沟矿床中银以独立矿物或类质同象产出,主要独立银矿物有自然银、辉银矿和硫铜银矿,主要类质同象矿物为银黝铜矿和含银黝铜矿。辉银矿以显微包体形式赋存于方铅矿中;硫铜银矿呈不等粒集合体分布于黄铜矿颗粒的边部;而自然银呈粒状分布于石英脉及碳酸盐矿物的晶隙间。     

灵寿县北营西沟银铅锌多金属矿区银的赋存状态

北营西沟银铅锌多金属矿床中银，主要以硫化物形式存在，主要有银锑黝铜矿、硫铜银矿、辉银矿等，自然银很少。银矿物呈它形粒状同脉石矿物及其它金属矿物镶嵌在一起或呈显微、超显微及胶状包嵌在方铅矿、闪锌矿和黄铜矿等矿物中，其中与方铅矿的关系更为密切。本文通过研究银的赋存状态，为选矿方法实验提供依据。     

金矿物及其赋存状态

已发现的金矿物有60余种。本文将其分为七类。在附表中列有20种较常见的金矿物及其鉴定特征。金在自然界中有三种赋存状态:可见独立矿物形式;呈次显微状于载体矿物中;或以原子状态混入其他矿物。金的工业矿物以第一种赋存状态为主,它们常与黄铁矿、毒砂、黄铜矿、磁黄铁矿、闪锌矿、方铅矿、黝铜矿和石英等连生,或以其作为载体矿物。呈次显微状的金,是以粒径小于0.2um的球粒形质点,呈机械混入物状态于黄铁矿等硫化物中。     

贵州银厂坡银矿床银矿物特征及其赋存状态

通过电子探针、化学分析、显微镜鉴定及野外观察等方法,对贵州威宁银厂坡银矿床的银矿物物理性质、化民分特征及银的赋存状态进行了研究。初步查明,银矿物主要有三种：自然银、螺硫银矿、银黝铜矿。在银黝铜矿中,Ａｇ的摩尔数与Ｓｂ、Ｚｎ的摩尔数呈明显正相关。银主要呈独立银矿物的形式赋存于Ｐｂ－Ｚｎ－Ａｇ和Ｐｂ－Ｃｕ－Ａｂ两类矿石中。     

福建碧田铜金银矿床的金属矿物研究

碧田矿床是成因上与燕山晚期次火山岩有关的以银为主的大型铜金银矿床。金属矿物种类复杂，除常见的黄铁矿、黄铜矿、斑铜矿外，还有多种铜铋硫盐矿物（锌砷黝铜矿、铋砷黝铜矿、铋锑黝铜矿、针硫铋铅矿、硫铋铜矿）、钨锡硫化物（硫铁锡铜矿、硫钨锡铜矿）及多金属硫化物。金银矿物除辉银矿外，主要是Ａｕ－Ａｇ系列的自然金、银金矿、金银矿及自然银。这些矿物形成于不同的物理化学条件下，大多数铜矿物、铜铋硫盐矿物和钨锡硫化物是在中高温（２６０—３８０℃）条件下、硫逸度较高（ｌｇｆＳ２＝－８．７４—－１２．０６）、流体盐度高并处于沸腾的状况下形成的；而多金属硫化物和金银矿物则主要是在中低温（１２０—２６０℃）条件下，硫逸度较低（ｌｇｆＳ２＝－１１．６—－１９．５），流体盐度也较低的状况下形成的。     

内蒙古大井矿床中银矿物的研究

本文总结了内蒙古大井矿床中银矿物的类型，产出特征以及矿物命名的问题，详细描述了黝铜矿族，浓红银矿，脆银矿，自然银以及含银的铅－铋（锑）硫盐类矿物等主要银矿物的产出状态和化学成分特征，并讨论了相应的形成条件，同时指出本区银矿物主要形成于两个矿化阶段，即：早期黄铜矿－黄铁矿阶段，主要形成了黝铜矿族的含银矿物以及辉锑银矿，硫锑铜银矿等含铜的硫盐类矿物，晚期方铅矿－闪锌矿阶段，形成的银矿物种类较为繁杂，除形成黝铜矿族矿物外，多数含铅，铋的硫盐矿物以及自然银、硫化物和浓红银矿、脆银矿等无铜的简单硫盐等均是在这一阶段形成。     

银多金属矿床中黝铜矿族银硫盐矿物的特征及其意义

在国内外几个不同成因类型的银多金属矿床内产出的黝铜矿族银硫盐矿物中,除朗达矿床见有砷黝铜矿和含银砷黝铜矿外,较普遍共同发育有黝铜矿、含银黝铜矿和银黝铜矿、而后两者是最主要或主要的工业银矿物之一。按国际矿物学协会新矿物及矿物命名委员会的矿物命名原则,黝铜矿族矿物所含的Ｆｅ、Ｚｎ、Ｈｇ、Ｃｄ、Ｍｎ等不可作为矿物种的命名元素。蔡家营矿床的含银黝铜矿和银黝铜矿以Ｆｅ、Ｚｎ含量近似而有别于其余矿床的富Ｆｅ贫     

醴陵市石景冲银矿床银的赋存状态

石景冲银矿床的热液成矿作用可分为三个阶段:①硫化物成矿前的石英—碳酸盐阶段;②石英、毒砂、黄铁矿阶段;③银铅锌多金属硫化物阶段。银主要以银矿物的形式产于第三阶段,与铅锌流化物密切共生,研究确定了四种银矿物:银黝铜矿、螺状硫银矿、深红银矿和自然银。据估算,银黝铜矿中的银占整个银矿床含银量的81.3％,其余以类质同像替代的形式存在于方铅矿为主的硫化物中。     

江西冷水坑矿田下鲍Ag-Pb-Zn矿床地质特征及银的赋存状态研究

下鲍大型Ag-Pb-Zn矿床位于江西冷水坑矿田西南部。矿床地质研究表明,成矿作用可以分三个阶段:(Ⅰ)闪锌矿-黄铁矿阶段;(Ⅱ)方铅矿-闪锌矿-银矿物阶段;(Ⅲ)黄铁矿-石英(方解石)阶段。岩矿石光薄片鉴定和电子探针分析表明,下鲍矿床主要金属硫化物为闪锌矿、方铅矿、黄铁矿及银矿物。电子探针分析显示,银主要以独立银矿物形式存在,金属硫化物中不可见银极少。银矿物种类主要为螺状硫银矿和自然银,呈裂隙银赋存于铁锰碳酸盐中或呈粒间银分布于铁锰碳酸盐粒间和早期硫化物晶隙间;另有少量硫银锡矿、含银黝铜矿、淡红银矿、金银矿及深红银矿、硫砷铜银矿等银矿物,呈亚显微粒状赋存于铁锰碳酸盐粒间或呈固溶体分离结构赋存于方铅矿、闪锌矿等硫化物中。主要银矿物大量赋存于铁锰碳酸盐中,表明银矿化与铁锰碳酸盐可能存在成因联系。     

金龙山-丘岭金矿床成矿流体的储运规律及区域找金方向

金龙山-丘岭金矿区含金矿源层为上泥盆统南羊山组和下石炭统袁家沟组.组成含金矿源层岩石为高频互层的细碎屑岩-碳酸盐岩,其中细砂岩、粉砂岩、碳酸盐岩含成矿流体物性较好,页岩、板岩含成矿流体物性较差,构成屏蔽层.金鸡岭Ⅰ级复式向斜控制着金、砷、锑等异常范围;松枣Ⅱ级复式背斜控制着金的矿化带;金龙山-丘岭金矿Ⅲ级背斜控制着金的矿(化)体;镇安-板岩镇断裂的次级断裂是金矿化体的容矿有利位置.在成矿过程中,构造变形与成矿流体的形成、运移及储集密切相关.其规律是:①原生构造导致成矿流体的初次聚集.②第一期构造变形导致成矿流体的聚集.③第二期构造变形导致成矿流体运移及金矿床形成.此期变形是金的主要成矿期.④第三期构造变形使成矿流体进一步聚集和金矿体的富集. ⑤第四期构造变形是石英方解石脉的形成时期.总结出矿床形成模式.据此提出了在4种不同的构造部位找金的方向.     

云南绿春杨家寨金多金属矿矿床特征及成矿规律

杨家寨金多金属矿位于西藏—三江造山系,兰坪—普洱双向弧后陆内盆地与绿春陆缘弧带结合部,矿体近矿围岩主要为下二叠统高井朝组安山质凝灰岩及安山岩,少部分为石英斑岩,矿体就位于与莫马洛断层（F4）成锐角度相交的次级构造、层间破碎带及层间剥离—滑脱构造带.成矿作用共分三个阶段：早二叠世晚期——矿源岩（层）形成阶段,燕山早期——矿床形成阶段;燕山晚期——矿床定位阶段.矿床类型为浅成低温热液构造—蚀变岩型多金属矿床.     

山西塔儿山地区燕山期岩浆演化及其对金属成矿的控制作用

构成山西南部塔儿山超单元的三个岩浆岩单元，是燕山期熔融程度较低的幔源岩浆，在深部岩浆房中分异演化，脉动侵位而成。本区金属成矿与矿质在岩浆演化不同阶段富集有关，同时受到不同演化阶段岩浆中主要元素含量制约，由此形成成矿作用的时空结构；早期二长闪长岩－铁成矿，中期石英二长岩－铜成矿，晚期霓辉正长岩－金成矿。     

Ore-bearing duplexes at the Malomyr orogenic gold deposit, Amur Region

This study made it possible to reconstruct three stages of the structure formation at the large Malomyr gold deposit in the Amur Region: (1) premineral folding and left-lateral strike-slip faulting; (2) synmineral thrust faulting, and (3) postmineral dike and neotectonic stage. The study has shown that the formation of the Malomyr deposit was related to the system of duplexes as the structural traps that are the most favorable for ore deposition. The left-lateral duplex hosts the major orebodies composed of refractory ore at the Central site of the deposit, whereas the highest-grade and readily processable ore from the Quartzitic site is localized in the right-lateral duplex. The development of both duplexes during the same stage of thrust faulting indicates that readily processable and refractory ores were formed almost simultaneously. The type of mineralization depends on structural conditions of ore deposition. Refractory ore with invisible gold was formed under compression, whereas the readily processable ore with free gold was deposited in the extension setting.     

Formation Mechanism of the Tongyu Gold Deposit,Shaanxi——A Discussion of a Model for the Formation of Syntectonic Gold Deposits

The formation of the Tongyu gold deposit, controlled by regional polyphase deformation-metamorphism.is closely related to the regional composite antiform-shear slip fracture zone. Late-stage reworking of theTaihua Group accounts for the enrichment of ore substances. It is a typical syntectonic gold deposit. The formation and evolution of the deposit involved four stages: (Ⅰ) the state of preparation of ore sub-stances, in which primary source beds originated: (Ⅱ) the stage of remobilization of ore substances, in whichregional progressive metamorphism and migmatization and thermodynamic-chemical differentiation led toremobilization of gold and its initial local concentration: (Ⅲ) the stage of gold deposit formation, in which re-gional folding produced concordant and cross shear-slip fractures and under the dynamic action gold was sepa-rated and migrated in a certain direction and concentrated to form a gold deposit: (Ⅳ) the stage ofsuperpositon, reworking and exposure of orebodies, in which the block uplifted and the deposit againunderwent reworking through faulting and mechanical differentiation.Thermodynamic mineralization played adominant role in the formation of the deposit.     

Gold–quartz deposits of the Zhdaninsky ore–placer cluster,eastern Yakutia: Structural control and formation conditions

Gold deposits and occurrences small in reserves and high in Au grade conventionally determine the line of prospecting in terrigenous sequences of the Verkhoyansk–Kolyma region. In this paper, the geological structure of such gold objects is considered with the example of the deposits and prospects making up the Zhdaninsky ore–placer cluster in the Republic of Sakha (Yakuia). From lithological, structural, and mineralogical–geochemical data, the formation conditions of ore-bearing complexes are specified, the geological evolution history of the northern Ol’chan Zone of the Kular–Nera Belt is reconstructed, and the zonal distribution of mineralization within the ore–placer cluster is revealed. The structural–compositional complexes were formed in the following succession: (1) sedimentation at the shelf of the passive margin accompanied by synsedimentation deformations; (2) metagenesis of sediments and the development of bedding-plane intraformational detachments of collision stage D₁ under conditions of tangential compression and accompanied by the formation of carbon dioxide–aqueous metamorphic fluid at a temperature of 300°C and under a pressure of 1.4 kbar; (3) folding and faulting of orogenic stage D₂ with the formation of synkinematic magmatic bodies, metasomatic alteration, and Au-bearig mineral assemblages. Small Au-bearing objects with veined mineralization and high Au grade are localized in structures of stage D₂ transverse to bedding-plane schistosity S₁. They form at the collision stage above intraformational detachment surfaces and are controlled by shear structures of the orogenic stage with misalignment of these deformations. The ore zoning is determined by the distribution of Co and Ni minerals and by variations in the anionic composition of ore (S, As, Sb).     

Geology and Mineralization at the Dajing Tin-polymetallic Ore Deposit, Inner Mongolia, China

Abstract: Dajing is a large-scale tin–polymetallic ore deposit in north China with Sn, Cu, Pb, Zn, Ag, and minor elements such as Co and In. The deposit is controlled by a passage-host structure system. Two groups of NE direction faults such as F₂ and F₁ are characterized by sinistral and multiphase activities, and the syn-ore NE faults with their derivative faults nearly in N-S direction constitute an important structure system as channelway for ore fluid. Around F₂ fault (mineralization center), metallic elements display horizontal zoning outwards from Sn, Cu to Cu, Sn, Pb, Zn, Ag and to Pb, Zn, Ag. Controlled by sinistral pull-apart vein system, the WNW direction host structure yielded the ore vein to "W" shape on horizontal plan while to staircase shape on vertical profile. Multiperiodic activities of the host structures system lead to multistage of ore mineralization. Four mineralization stages are recognized in the main mineralization, i.e. 1) cassiterite–arsenopyrite–quartz stage, 2) cassiterite-sulfide (or Cu–poly–metallic mineralization) stage, 3) massive pyrite stage, and 4) galena-sphalerite stage. Besides, fluid activities are identified here at the pre-mineral stage of the formation of quartz veins and sheared deformation, and at the post-mineral stage of quartz–calcite–fluorite deposition.
The earlier tin-rich ore solution raised from NE faults and its nearly N-S derivatives filled the NW-WNW direction fractures, and formed tin ore veins. Subsequent mineralization of Cu-polymetallic stage, pyrite stage and galena-sphalerite stage, overlapping on the same fracture system, sequentially expanded outwards from the fractures, and produced different kinds of ore types and mineralization zoning.     

High-grade iron ore at Windarling, Yilgarn Craton: a product of syn-orogenic deformation, hypogene hydrothermal alteration and supergene modification in an Archean BIF-basalt lithostratigraphy

Banded iron formation (BIF)-hosted iron ore deposits in the Windarling Range are located in the lower greenstone succession of the Marda–Diemals greenstone belt, Southern Cross domain, Yilgarn Craton and constitute a total hematite–martite–goethite ore resource of minimum 52 Mt at 60 wt.% Fe (0.07 P). Banded iron formation is interlayered with high-Mg basalts at Windarling and precipitated during episodes of volcanic quiescence. Trace element content and the rare earth element (REE) ratios Y/Ho (42 to 45), Sm/Yb (1.5), together with positive La and Gd anomalies in ‘least-altered’ hematite–magnetite–metachert–BIF indicate the precipitation from Archean seawater that was fertilised by hydrothermal vent fluids with a basaltic HREE-Y signature. Hypogene iron ore in sub-greenschist facies metamorphosed BIF formed during three distinct stages: ore stage 1 was a syn- to post-metamorphic, syn-D₁, Fe–Ca–Mg–Ni–Co–P–REE metasomatism that produced local Ni–REE-rich Fe–dolomite–magnetite alteration in BIF. Hydrothermal alteration was induced by hot fluid flow controlled by brittle–ductile reactivation of BIF-basalt margins and crosscutting D₁ faults. The Ni–Co-rich content of dolomite and a shift in REE ratios in carbonate-altered BIF towards Archean mafic rock signature (Y/Ho to 31 to 40, Sm/Yb to 1 to 2 and Gd/Gd* to 1.2 to 1.4) suggest that high-Mg basalts in the Windarling Range were the primary source of introduced metals. During ore stage 2, a syn-deformational and likely acidic and oxidised fluid flow along BIF-basalt margins and within D₁ faults leached carbonate and precipitated lepidoblastic and anhedral/granoblastic hematite. High-grade magnetite–hematite ore is formed during this stage. Ore stage 3 hydrothermal specular hematite (spcH)–Fe–dolomite–quartz alteration was controlled by a late-orogenic, brittle, compressional/transpressional stage (D₄; the regional-scale shear-zone-related D₃ is not preserved in Windarling). This minor event remobilised iron oxides, carbonate and quartz to form veins and breccia but did not generate significant volumes of iron ore. Ore stage 4 involved Mesozoic(?) to recent supergene oxidation and hydration in a weathering environment reaching down to depths of ～100 to maximum 200 m below surface. Supergene ore formation involved goethite replacement of dolomite and quartz as well as martitisation. Important ‘ground preparation’ for supergene modification and upgrade were mainly the formation of steep D₁ to D₄ structures, steep BIF/basalt margins and particularly the syn-D₁ to syn-D₂ carbonate alteration of BIF that is most susceptible to supergene dissolution. The Windarling deposits are structurally controlled, supergene-modified hydrothermal iron ore systems that share comparable physical, chemical and ore-forming characteristics to other iron ore deposits in the Yilgarn Craton (e.g. Koolyanobbing, Beebyn in the Weld Range, Mt. Gibson). However, the remarkable variety in pre-, syn- and post-deformational ore textures (relative to D₁ and D₂) has not been described elsewhere in the Yilgarn and are similar to the ore deposits in high-strain zones, such as of Brazil (Quadrilátero Ferrífero or Iron Quadrangle) and Nigeria. The overall similarity of alteration stages, i.e. the sequence of hydrothermal carbonate introduction and hypogene leaching, with other greenstone belt-hosted iron ore deposits supports the interpretation that syn-orogenic BIF alteration and upgrade was crucial in the formation of hypogene–supergene iron ore deposits in the Yilgarn Craton and possibly in other Archean/Paleoproterozoic greenstone belt settings worldwide.     

变质矿床成因分类的讨论

在探讨了变质矿床的定义并结合前人研究的基础上,对变质矿床初步提出了一个新的成因分类方案。该方案共分为五个大类和十三个亚类,并对每个大类和亚类都提出了一些代表性矿床实例。新的变质矿床成因分类方案为：（1）受变质矿床类,分为受变质硅铁质建造沉积矿床、受变质硅铁质建造火山–沉积矿床、受变质其它建造沉积–火山沉积矿床、受变质火成岩改造矿床和受变质细碧角斑质火山喷发沉积矿床五个亚类;（2）区域变质作用变成矿床类,分为变质重结晶型、变质化学反应重组型和变质热液型三个亚类;（3）局部变质作用变成矿床类,分为接触交代夕卡岩矿床、局部接触热变质变成矿床和局部动力变质变成矿床三个亚类;（4）受变质沉积–火山沉积变质热液叠加改造矿床类;（5）混合岩化作用形成矿床类,又分为混合岩化交代型和后期混合岩化热液型两个亚类。     

胶东大庄子金矿地质特征与成因探讨

大庄子金矿是我国首次发现赋存于胶东变质岩中大规模韧-脆性剪切带内的蚀变岩型及石英脉型金矿床.金矿化与绢英岩化、黄铁矿化、硅化和碎裂岩化有关.矿体受韧-脆性剪切带、黄铁绢英岩化、晚元古代晚期角闪岩相变质岩的共同控制.矿石矿物组合以自然金-金属硫化物-架状硅酸盐为主的组合类型.矿床属于在韧-脆性剪切作用下,与含金量较高的下元古界荆山群变质岩的形成、演化有成因联系的蚀变、重熔、交代中温动力热液改造型金矿床.