湖南省溆浦县南江坪金矿地质特征与控矿规律

南江坪金矿主要矿体产于五强溪组上段浅变质碎屑岩系岩层劈理化带,严格受陶金坪—龙鼻桥复背斜控制,成带状平行展布。矿区主要控矿和容矿构造为NE向剪切破碎蚀变带,其上下盘剪切滑动面清晰,剪切破碎蚀变带内NE向硅化网脉带与蚀变板岩互层产出;NE向硅化网脉带张性充填的低序次NE向石英细脉和NW、NNE、NNW、近SN向的石英细脉穿插形成共轭、棱型张性硅化网脉带,张性硅化网脉带内的石英细脉及硅化蚀变岩中发育毒砂化、黄铁矿化等,是金的主要含矿富集部位。褪色化、硅化、毒砂化、黄铁矿化等与成矿关系密切,毒砂是矿区主要载金矿物。     

湖南江溪垄金锑矿床地质地球化学特征及开发应用

湖南江溪垄金锑矿床赋存于新元古界板溪群五强溪组浅变质岩系中.成矿严格受NE向剪切断裂带控制.该矿系金锑共（伴）生矿床.矿体呈陡倾斜的交错脉状产出,沿走向、倾向变化均较稳定.金主要产于近矿蚀变围岩中,毒砂为金的重要载体矿物;锑的富集则与硅化关系密切.矿石为高砷含金锑矿石.以锑为主的选矿试验结果表明,主要回收对象为辉锑矿,并可综合回收金.     

泥潭冲金矿床中毒砂标型特征及金的赋存状态

泥潭冲金矿床为主要受近EW向脆-韧性剪切带控制的砷金矿床,是龙王江锑砷金成矿区最具代表性和经济意义的金矿床.文章阐述了矿床地质特征,探讨了载金矿物毒砂的标型特征和金的赋存状态,认为毒砂中的"不可见金"主要为纳米级微粒状的自然金.     

湘西龙王江锑砷金矿床地质地球化学特征

龙王江锑砷金矿床具明显的层控特征,空间分布严格受构造控制,褪色蚀变带是矿床赋存的重要标志,矿化主要与毒砂化和硅化有关。原生晕综合异常是成矿作用的地球化学标志。矿石中的金、砷含量呈正相关,金和砷的相关系数近于1。毒砂可作为寻找锑砷金矿床的标型矿物,而砷则是其标型地球化学指示元素。成矿作用是在中低温(330—178℃)条件下进行的,硫同位素组成具变质还原硫特点。该矿属于与元古界浅变质岩有关的变质热液型金矿床。     

南秦岭赋存于沉积岩中的金龙山金矿带主要载金矿物铁矿、毒砂研究

金龙山金矿是产于南秦岭镇安－旬阳晚古生代沉积盆地细碎屑岩－碳酸盐建造中的微细浸染型金矿,主要载金矿物毒砂,黄铁矿,粒度多为10－100um,约为次显微状金颗粒直径的1000倍左右,黄铁矿为含砷铁矿,并常作为原生沉积成因草莓状,球菌状黄铁矿的增生环带,因而常规方法无法分出原生沉积因黄铁矿热液阶段黄铁矿,毒砂,用于单矿物化学分析,同位素,热电性测定的黄铁矿样品多为热液改造后多段黄铁矿与热液阶段黄铁矿,毒砂,用于单矿物化学分析,同位素,热电性测煊的黄铁矿样品多为热液造后多阶段黄铁矿的混合样品,毒砂的含金性比黄铁矿更好,成岩期黄铁矿无砷很低,金矿成矿阶段黄铁矿亏硫,毒砂亏砷,金、砷最大可能是含矿热液带入的,成岩期黄铁矿可能提供了部分硫,黄铁矿的热电系数范围较大,毒砂亏砷,金,砷最大可能是含矿热液带入的,成岩期黄铁矿可能提供了部分硫,黄铁矿的热电系数范围较大,空穴导型,电子导型均有,以空穴型为主,矿带内化物的硫同位素呈多垛状产出,但主要集中于6‰－17‰之间,铅同位素反映了造山带特征,与汞锑矿石的铅同位素相近,金锑成矿与深大断裂的活动有关。     

陶金坪金矿区控矿规律及找矿方向分析

陶金坪金矿区主要矿体均产出于新元古界板溪群五强溪组上段浅变质碎屑岩系岩层劈理化带由陡变缓的交接部位,严格受陶金坪―龙鼻桥复背斜控制,成带状分布,褪色化、硅化、毒砂化、辉锑矿化等与成矿关系密切。矿区内单个矿床规模均为小型金锑矿床,江溪垄―中都连接部位的晒谷岩矿段构造成矿条件好,重砂异常明显,预计能探明一处小型砷金矿床。芭蕉冲区域是江东湾矿段的北东延伸,伞溪坳区域水系沉积物异常明显,是下一步预查工作的选择靶区。     

南秦岭赋存于沉积岩中的金龙山金矿带主要载金矿物黄铁矿、毒砂研究

金龙山金矿是产于南秦岭镇安-旬阳晚古生代沉积盆地细碎屑岩-碳酸盐建造中的微细浸染型金矿.主要载金矿物毒砂、黄铁矿,粒度多为10~100 μm,约为次显微状金颗粒直径的1000倍左右.黄铁矿为含砷黄铁矿,并常作为原生沉积成因草莓状、球菌状黄铁矿的增生环带,因而常规方法无法分离出原生沉积成因黄铁矿与热液阶段黄铁矿、毒砂.用于单矿物化学分析、同位素、热电性测定的黄铁矿样品多为热液改造后多阶段黄铁矿的混合样品,毒砂的含金性比黄铁矿更好.成岩期黄铁矿无砷或砷很低,金矿成矿阶段黄铁矿亏硫,毒砂亏砷.金、砷最大可能是含矿热液带入的,成岩期黄铁矿可能提供了部分硫.黄铁矿的热电系数范围较大,空穴导型、电子导型均有,以空穴型为主.矿带内硫化物的硫同位素呈多垛状产出,但主要集中于6‰~17‰之间.铅同位素反映了造山带特征,与汞锑矿石的铅同位素相近,金锑成矿与深大断裂的活动有关.     

湖南省桃江县板溪锑矿床地质特征研究

板溪锑矿床位于桃江板溪锑矿成矿带内,开采历史悠久,但对区域地质和矿床地质缺乏深入研究。为了在区域上进一步寻找该类型锑矿,在充分收集前人资料和野外调研的基础上,总结区域地质、矿床地质特征,深入研究控矿因素和成矿时代。结果表明: 锑矿多分布于区域性大断裂旁侧次级断裂与背斜交汇处,深断裂控制金锑成矿带的展布,矿体主要产于NW向、NE向、近EW向、NNW向和NNE向次级断裂中; 区域锑矿的形成开始于加里东期,在燕山期达到高峰。矿区背斜或背斜倾伏端控制了矿床的定位,而背斜中的次级褶皱、断裂、层间破碎带及倾伏端等控制了矿体。矿体主要赋存于前寒武纪冷家溪群、板溪群浅变质岩系中,其次赋存于南华纪—志留纪、泥盆纪—石炭纪的碎屑岩及碳酸盐岩中; 围岩蚀变主要有毒砂化、黄铁矿化、硅化、绢云母化、绿泥石化、碳酸盐化等; 矿石自然类型有石英-辉锑矿矿石、黄铁矿-石英-辉锑矿矿石、毒砂-黄铁矿-石英-辉锑矿矿石、碳酸盐-石英-辉锑矿矿石; 矿床成矿时代属燕山期。研究成果为进一步开展板溪锑矿床找矿提供借鉴和指导作用。     

一种未定名的钴矿物结构研究

对东昆仑肯德可克钴铋金多金属矿床发现的未定名的钴矿物成分和晶体结构进行了研究.该矿物是以Co、Fe、As和S为主组成的正交晶系矿物,与毒砂、钴毒砂、铁硫砷钴矿和斜硫砷钴矿不同,表明该矿物为一种新的钴工业矿物.     

甘肃岷县寨上金矿床地质特征及成因初探

寨上金矿床位于西秦岭岷-礼前渊盆地西侧南部,发育在不同岩性和不同粒度组成海底斜坡扇环境下的浊积岩系中。主要的含矿建造为晚泥盆系e组的一套沉积岩系。岩石具有碳-钙-泥质沉积岩高频叠置组合。控矿构造属于韧性-脆性递进剪切变形构造性质,该构造呈NWW向延伸,南倾,倾角30°～50°,具有递进多期多阶段活动的特点,是本区控矿和成矿的主要决定因素。含矿围岩热液蚀变作用微弱,主要表现为浸染状、细脉状-浸染状的含砷黄铁矿化、毒砂化、微细脉与细网脉状硅化、铁白云石化,均与金矿化密切相关。矿石构造以微细粒稀疏浸染状构造、微细脉-稀疏浸染状构造、团块-浸染状构造、草莓状构造为主,矿石结构以自形-半自形微细粒状结构、半自形-他形粒状结构、增生环带结构、包含结构为主。矿区发现了南、北两个矿带,北矿带主要发育黄铁矿型金矿体、黄铁矿-毒砂型金矿体、锑-金型金矿体;南矿带主要发育铜金矿体。因此认为,①中泥盆统e组细碎屑岩-碳酸盐岩为本区矿源层;②寨上金矿区控矿构造属于韧-脆性递进剪切变形构造性质,具有递进多期多阶段活动的特点,是本区控矿和成矿的主要决定因素;③含砷黄铁矿、毒砂的增生环带,是由含砷低的黄铁矿或毒砂内核和含砷较高的黄铁矿或毒砂增生环带构成;④矿床具有后生中低温热液特点,将寨上金矿确定为经典卡林型矿床类型。     

Gold mineralization in the West Hoggar shear zone,Algeria

The Amesmessa gold prospect is located along a vertical N-S-trending crustal-scale ductile shear zone; stretching lineations are subhorizontal. This major shear zone is a Late Pan African dextral strike-slip fault of the Pharusian Belt of the Tuareg Shield (Algeria). The Amesmessa shear zone is asymmetric: strong thermal and deformational gradients are present along its western border where biotitic ultramylonites are in contact with a rigid Archean complex (In Ouzzal block), whereas there is a progressive gradation, through mylonite then protomylonite, to the Proterozoic gneiss of the Eastern block which displays co-axial Pan African structures. The Amesmessa shear zone is characterized by the presence of a felsic dike complex emplaced during shearing, and forming the most important parent material for ultramylonites. Basic magmas and carbonatites also intruded within the shear zone. The gold-rich quartz veins are located within the ultramylonitic western part of the shear zone. These N-S-trending laminated quartz veins formed during the late increments of shearing (plastic/brittle transition), by repeated syntectonic hydraulic fracturing along zones of rheological contrast parallel to foliation. The ore mineral association (pyrite, galena, native gold, sphalerite) crystallized in the deformed quartz matrix along late shear planes. Undeformed E-W trending banded quartz veins are present in the mylonitic eastern part of the shear zone; their gold content is low and no native gold has been observed. A strong hydrothermal alteration resulted in the development (along the walls of the N-S gold-bearing quartz veins) of a 5-m-wide carbonate-sericite-albite-pyrite secondary mineral association which implies an important CO₂ supply and moderate temperature conditions. There is no alteration halo around the E-W quartz veins. Ultramylonites, hydrothermally altered rocks and quartz veins display similar REE patterns characterized by strong LREE enrichments. Shear-related fluids could be likely parental fluids for the Amesmessa gold mineralization and the associated hydrothermal alteration. Hydrothermal fluids were drawn into dilation zones and filled opening fractures along the main planar discontinuity of the most deformed rocks. The supply of CO₂ may come from a deep-seated source as suggested by the presence of carbonatite dikes in the shear zones and the existence of CO₂-H₂O-rich fluid inclusions in quartz. The location of the gold-bearing quartz veins in the western part of the shear zone can be explained by the presence of strong thermal and rheological gradients.     

The Archaean gold mineralization in Rämepuro, llomantsi greenstone belt, Eastern Finland

The Rämepuro gold mineralization is situated in the Hattu sub-belt of the Archaean Ilomantsi greenstone belt, Eastern Finland. It consists of gold-bearing quartz veins located mainly within the shear zone contact between felsic volcanics and sedimentary rocks. The quartz veins cutting all the types of Archaean rocks are composed mainly of quartz and tourmaline and minor amounts of pyrite, pyrrothite, chalcopyrite, sphalerite, siderite, hedleyite, native bismuth and gold. The highest amounts of gold are found in the quartz-tourmaline veins, with abundant chalcopyrite and sphalerite. Gold has its best correlation with Bi, Te, S, Zn and Cu. The minor mineralogical alterations (sericirization, saussuritizarion, chloritization) are connected with variations in some major elements. The quartz veins were emplaced under greenschist facies conditions after the peak in the lower amphibolite facies metamorphism.     

四川锦屏山地区金矿床的成矿机理和成因探讨

在对研究区典型金矿床的矿化地质特征、围岩蚀变特征分析的基础上,讨论了四川锦屏山地区金矿床的成矿机理和矿床成因。锦屏山地区金矿床的含矿围岩以浅变质的三叠系粉砂质片岩为主,金矿床围岩中广泛发育碳酸岩化（早期）和硅化（后期）,前者以铁白云石化为特征,后者以黄铁绢英岩化、绿泥石化和石英脉发育为特征。碳酸岩化主要发生在碳酸岩脉与泥质粉砂岩的接触带上的粉砂岩一侧,由碳酸岩脉侵入时的热液交代岩石中的泥质矿物而形成。金矿体的走向与碳酸岩化带的产状基本一致,金主要富集于硅化强烈、黄铁绢英岩化发育地段。碳酸岩化地层中具有较高的含金背景,指示成矿物质金来源于地幔,而矿化主要发生在黄铁绢英岩化和硅化带及石英硫化物脉中。结合矿床的同位素地球化学特征,认为研究区金矿的成矿作用主要是后期热液的改造作用中金元素发生再次富集的结果。金矿的形成经历了碳酸岩脉侵入、地层发生铁白云石化并初步富集形成矿源层（岩）阶段和以硫化物石英脉为代表的热液期的大规模富集成矿两个阶段,矿床的成因类型因属于改造型金矿床。     

玲珑金矿田10号断裂及其成矿分析

10号是玲珑金矿田内发育的一条高角度断裂,构造岩破碎,结构松散.除其内部碎裂石英脉部分重新胶结外,其他构造岩均未胶结.经过构造特征分析,其形成于主成矿阶段,而后期又发生多次活动,近几年在该断裂中发现了具有工业价值的矿体,通过剖面与平面地质资料的对比分析、化学取样分析及玲珑金矿田成矿时期研究,10号断裂内发育的工业矿体属早期形成的石英脉矿体与后期断裂叠加的结果,早期形成的石英脉在构造动力作用下发生破碎并分散到断裂带中,加上金元素在地质历史时期内发生短距离运移,形成了目前的工业矿体.10号断裂多次活动对早期形成的矿脉起破坏作用并使金元素重新分配.     

新疆胜利达坂金矿区金矿化特征

胜利达坂金矿区,发育近EW向的韧性剪切带。该剪切带是区内金矿的主要控矿构造,控制了矿床、矿体及矿化体的分布。矿体主要沿韧性剪切带糜棱面理分布。矿石的主要类型是浸染糜棱岩型和变形石英脉型。成矿的最有利部位是剪切带内应力梯度大的地带。区内乳白色变形石英脉具有很大的找金潜力。该区金矿属韧性剪切带型金矿。     

青海双朋西-斜长支沟地区金矿成矿地质条件及成矿规律

双朋西—斜长支沟地区是青海东部较为重要的贵金属和有色金属成矿区。在已探明的金矿床中,有矽卡岩型、破碎蚀变岩型、石英脉型三类。金的成矿作用受构造-岩浆控制,在不同的岩性组合中分布着不同类型的金矿。矽卡岩型和石英脉型金矿赋存于二叠系中,破碎蚀变岩型金矿赋存于三叠系中。     

~(40)/Ar~(39)Ar Ages of Auriferous Quartz Veins from the Fengyang and Zhangbaling Regions and Their Geological Significance

1IntroductionAuriferousquartzveinsarecommonintheFengyangandZhangbalingregionsofAnhuiProvinceandtheyconstitutetheRongdu ,Zhuding ,Dagongshan ,MaoshanandShangchenggolddepositsandalotofgoldperspectives .TheRb SrisochronagesofalterationmineralsfromtheRongduandDagongshangolddepositsare (10 9.0± 4 .4 )Maand (15 3.76± 11.2 )Ma ,respectively (Dongetal .,1995 ) .Thereisalargedifferenceinagebetweenthetwogolddeposits ,butitcanbeseenthatthegolddepositswereformedinLateJurassictoEarlyCretaceous .A…     

益阳硐坡金矿地质特征及富集规律初步探讨

益阳岩金矿床的勘查研究表明，该区含金石英脉均受剪切片理化带控制。构造剪切作用形成塑性变形褶皱和糜棱岩化，并使早期石英脉发生塑性变形或脆性碎裂，为成矿提供了构造空间。随着剪切作用的持续进行，派生了里德尔共轭裂隙，再次为金矿化提供了容矿空间。含矿溶液沿裂隙充填或胶结后期糖粒状石英，形成特殊的合会剪切带型金矿。因此，本文提出在北东一近东西向雪峰孤形构造带找金时，应视剪切片理化带为重点靶区，４１８队在硐坡矿段的金矿预测与验证说明，这一认识具有指导意义。     

冀北东坪金矿床深部-外围的构造-蚀变-流体成矿研究

冀北东坪金矿田是我国首次在碱性杂岩体内发现的金矿床,曾被认为是与碱性岩有关的金矿床。近年来年代学数据表明,东坪-后沟一带金矿的赋矿碱性杂岩体形成于海西期,而成矿却主要发生在燕山期。金矿床严格受构造裂隙控制,构造-蚀变-流体成矿作用显著,钾长石化是最重要的蚀变。由未蚀变岩石向矿体和断裂带中心方向,典型的构造-蚀变-矿化分带依次为:0-原岩(二长岩、正长岩)带,I-微斜长石化带,II硅化绢云母化微斜长石岩带,III碎裂微斜长石岩带,及IV断层泥。从0带到III带,Au含量增加,Ag、Cu、Pb、Zn、Mo也略有增加。东坪金矿构造-蚀变-矿化阶段可分为4个:Ⅰ钾长石-石英脉阶段;Ⅱ黄铁矿-白色石英阶段;Ⅲ多金属硫化物-烟灰色石英脉阶段;Ⅳ晚期碳酸盐阶段。深部中段各阶段脉石英的流体包裹体研究表明, 在I、II、III阶段均发育富CO₂包裹体。第Ⅰ阶段钾长石石英脉L-V型包裹体均一温度(Th)为220.3~359℃,盐度1.1%~3.1% NaCleqv;H₂O-CO₂型包裹体Th在346.5~383.5℃。第Ⅱ阶段黄铁矿白色石英脉中L-V型包裹体Th范围是217.2~372.5℃,盐度在1.1%~5.7% NaCleqv;H₂O-CO₂型包裹体Th在241.2~396.7℃,盐度为2.2%~6.2% NaCleqv。第Ⅲ阶段的烟灰色石英脉中L-V型包裹体Th范围为158.2~350.5℃,盐度在0.7%~5.5% NaCleqv;H₂O-CO₂型包裹体Th范围在215.2~378℃之间,盐度范围在3.0%~6.0% NaCleqv。第Ⅳ阶段晚期石英脉L-V型包裹体Th范围为151.2~249.8℃,盐度在0.9%~8.3% NaCleqv。矿区外围转枝莲矿段的II阶段白色石英脉中包裹体的Th范围为220~416.2℃,III阶段烟灰色石英脉的Th范围为195.3~425℃。富金石英脉形成于中高温(＞300℃,可达400℃以上)、中深压力(70~160MPa以上)条件下。其成矿背景、热液蚀变、矿物共生组合及流体性质与典型的造山型金矿有一定的差别,归属于"与侵入岩有关的金矿床"更合理。     

Gold Mineralization and Occurrence of Sinter in the Hoshino Area, Fukuoka Prefecture, Japan

Abstract. Several epithermal gold deposits occur in the Hoshino area, which is located in the western end of the late Cenozoic Hohi volcanic zone, north‐central Kyushu, Japan. The area is characterized by intermediate to felsic extrusive rocks of Pliocene age. In the Hoshino area, the shallow manifestation of the hydrothermal activity is exposed on the surface. Several outcrops of sinter are still preserved on the top of hydro thermally altered volcanic rocks, and high‐grade gold‐bearing quartz veins occur on the surface at lower levels. The hydrothermal alteration resulted into well‐developed alteration zones. The zonal alteration pattern, primarily of near‐neutral pH type, is characterized by the outer smectite zone of a lower temperature, and the inner mixed layer minerals zone of a higher temperature. Quartz vein‐related or fracture‐controlled alteration, is represented by the occurrence of interstratified illite/smectite and K‐feldspar, suggesting a potassium‐enriched alteration. The mineralization in the Hoshino area is recognized on the surface by the occurrence of gold‐bearing quartz veins distributed mainly in the mixed layer minerals zone. The fracture system related to the gold mineralization is mainly characterized by NW‐SE trend. The alteration pattern and the mineralogical composition of the veins suggest that the mineralizing fluids had near‐neutral pH and the mineralization is of low‐sulfidation‐type. Fluid inclusion data and textures observed in quartz veins indicate that gold precipitated during boiling. The chemical composition of quartz veins shows that high‐grade gold‐bearing quartz veins are characterized by higher content of Al₂O₃, K₂O and Rb. Several outcrops of silica‐sinters are distributed on the top of the mixed layer minerals zone. Although their structures are not very well preserved, because of later silicification, the Hoshino sinters still show characteristic textures identical to those observed in modern sinters, such as the presence of plant fossil incorporated into the sinters, the strongly developed depositional laminations and the columnar structures perpendicular to the depositional surfaces. Quartz is the only silica mineral constituting the Hoshino sinters presently. The conversion of amorphous silica into quartz was probably governed by higher temperatures resulting from later hydrothermal activity. This later hydrothermal activity is reflected by the intense silicification affecting mainly the lower parts of the sinters and also by the presence of quartz veins cutting the sinters. The distribution of sinters in the Hoshino area is very significant. The presence beneath the sinters of concealed high‐grade gold‐bearing quartz veins should be highly considered and exploration work is strongly suggested.