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1.
金厂特大型金矿床的地质特征与成因研究   总被引:18,自引:0,他引:18  
金厂特大型金矿床产于吉黑东部兴凯地块太平岭隆起与老黑山断陷的交接部位,矿区外围出露新元古界黄松群变质岩系。本区燕山期岩浆活动可分为5期,分别为燕山早期第一阶段闪长岩(δ52-1)、燕山早期第二阶段文象花岗岩(γo52-2)、燕山早期第三阶段花岗岩(γ52-3)、燕山晚期第一阶段花岗斑岩(γπ53-1)、燕山晚期第二阶段闪长玢岩脉(δμ53-2),形成岩浆穹窿型构造和隐爆角砾岩筒构造,并叠加大规模的热液蚀变活动,金矿化与第4、5期岩浆活动紧密相关。金矿矿体产状有三种类型:岩浆穹窿构造型、隐爆角砾岩型和环状放射状断裂型。矿石类型主要有含金黄铁矿化石英脉、含金石英黄铁矿脉、含金多金属硫化物石英脉、含金黄铁矿化方解石脉等。金矿成矿年龄为119.40 -122.53 Ma。金矿体受统一的构造-岩浆流体蚀变系统控制,成矿物质来源于深部,成矿流体为岩浆水,晚阶段有少量大气水加入。成矿环境为中高温、中等压力,流体盐度为中等偏高,流体性质为弱碱性、弱还原性,属于K -Na - Ca2 -Cl--SO42-型流体。金在成矿流体中以[Au(HS)2]-、[AuCl2]-、[Au(CO3)]-及[Au(HCO3)2]-等络合物形式存在,当温度、压力下降时,溶液由酸性演化为弱酸性再到弱碱性时,络合物离解,金沉淀成矿。  相似文献   

2.
甘肃北山拾金坡金矿床地质特征及成因分析   总被引:1,自引:1,他引:1  
安国堡 《矿床地质》2006,25(4):483-490
拾金坡金矿是甘肃北山南带较为典型的含金硫化物石英脉型金矿床,矿化富集与加里东晚期—海西早期拾金坡复式岩体密切相关。矿体产于岩体的内接触带,产出部位明显受近EW向断裂破碎带的控制。矿体主要为大脉状、脉状、透镜状。矿床中发育一套典型的中温热液成因的矿物组合,矿石以强烈的绢云母化、碳酸盐化、硅化和黄铁矿化为特征,矿石的金属矿物组合为自然金_银金矿_黄铁矿_方铅矿_闪锌矿_黄铜矿,矿化属中温热液成因。硫和铅同位素显示成矿金属物质主要来自围岩,即斑状花岗岩;氢和氧同位素组成表明成矿流体来自花岗岩浆水。成矿时代属早—中海西期。因此可推断,拾金坡金矿床属于与构造_岩浆活动有关的中温岩浆热液成因矿床。  相似文献   

3.
晋东北燕山期岩浆活动受区域性构造控制,具有北东成带,带内成区的分布规律,时间上可划分为150~160Ma、130~140Ma和85~127Ma三个高峰期。岩浆岩可划分为以花岗闪长岩—二长花岗岩—中细粒-粗粒斑状黑云母花岗岩等和以闪长岩—花岗闪长斑岩—花岗斑岩—石英斑岩等为主体的两大岩石组合,后者与金多金属矿床成矿关系密切。主要岩浆岩为过铝质碱性岩类,具有埃达克质岩石的亲和性;成因上属于I型,具同源演化关系。其形成可能与华北板块中生代岩石圈大规模减薄所引发的壳幔相互作用密切相关。与燕山期岩浆活动相对应,区域金多金属成矿也具有集中分布和多期成矿的特点。在类型上,主要包括斑岩型Mo-Au矿床、矽卡岩-热液脉型Au、Fe矿床和爆破角砾岩-热液石英脉型Au或Cu-Ag,Ag-Pb-Zn等矿床。有时在同一个成矿集中区内可见有多型一体的复杂组合,并在空间上具有明确的元素分带关系;在时间上,150~160Ma,主要与(二长)闪长岩或石英闪长岩、花岗闪长岩等有关,形成以钼-金为主的矿化;130~140Ma,主要与石英闪长岩、石英斑岩等有关,形成大规模金矿化;85~127Ma,主要与花岗斑岩、石英斑岩、隐爆角砾岩等相关,形成了强烈的银多金属矿化。不同类型矿床成矿热液主要源自相关的岩浆体系。华北板块中生代发生区域性构造体制转折,岩石圈大规模减薄及在此背景下发生的陆内造山作用是区域大规模岩浆活动和成矿作用的重要动力学机制。  相似文献   

4.
新疆西南天山金矿床主要类型、特征及成矿作用   总被引:6,自引:1,他引:6  
文章在总结前人研究成果的基础上,综合论述了西南天山金矿的成矿地质背景、金矿床的时空分布和基本特征。根据矿床地质特征和控矿因素,将西南天山的金矿划分为与剪切带有关的金矿床、与侵入岩有关的金矿床(包括斑岩型)、石英-重晶石脉型金矿床、与火山岩有关的金矿床和矽卡岩型金矿床5类,其中与剪切带有关的金矿床是最重要的矿床类型。探讨了西南天山金矿的成矿时代、成矿物质和成矿流体来源,以及成矿地球动力学机制。提出与剪切带有关的金矿床成矿物质主要来源于岩浆和海相碳酸盐岩,成矿流体主要来源于岩浆水或主要来自大气降水,混合少量岩浆水。石英-重晶石脉型金矿床成矿物质来自容矿地层,成矿流体主要来源于沉积建造水。与剪切带有关的金矿、与侵入岩有关的金矿、石英重晶石脉型金矿和矽卡岩型金矿成矿时代主要集中在二叠纪—三叠纪,形成于后碰撞构造演化阶段。斑岩型和浅成低温热液型金矿床形成于岛弧挤压环境。  相似文献   

5.
TheWulong lode deposit contains over 80 tonnes of gold with an average grade of 5.35 g/t.It is one of the largest deposits in Dandong City,Liaoning Province in northeast China.Previous studies on the deposit focused on its geological characteristics,geochemistry,fluid inclusions,and the timing of gold mineralization.However,controversy remains regarding the origin of the ore-forming fluids and metals,and the genesis of the gold deposit.This paper presents zircon UePb and pyrite RbeSr ages and S,Pb,He,and Ar isotopic results along with quartz H and O isotopic data for all litho-units associated with the deposit.Laser ablation inductively coupled mass spectrometry measurements yielded zircon UePb dates for samples of pre-mineralization rocks like granite porphyry dike,the Sanguliu granodiorite,fine-grained diorite,and syn-mineralization diorite,as well as post-mineralization dolerite,and lamprophyre;their emplacement ages are 1261 Ma,1241 Ma,1231 Ma,1201 Ma,1192 Ma,and 1152 Ma,respectively.The pyrite RbeSr isochron age is 1191 Ma,indicating that both magmatism and mineralization occurred during the Early Cretaceous.The d18OH2O values of ore-forming hydrothermal fluids from the quartzepolymetallic sulfide vein stage vary from 4.8&to 6.5&,and the dDV-SMOW values are between67.7&and75.9&,indicating that the ore-forming fluids were primarily magmatic.The noble gas isotope compositions of fluid inclusions hosted in pyrite suggest that the ore-forming fluids were dominantly derived from crustal sources with minor mantle input.Sulfur isotopic values of pyrite vary between 0.2&and 3.5&,suggesting that S was derived from a homogeneous magmatic source or possibly from fluids derived from the crust.The Pb isotopic compositions of sulfides(207Pb/204Pb?15.51 e15.71,206Pb/204Pb?17.35e18.75,208Pb/204Pb?38.27e40.03)indicate that the Pb of the Wulong gold deposit is a mixture of crust and mantle components.Geochronological and geochemical data,together with the regional geological history,indicate that Early Cretaceous magmatism and mineralization of the Wulong gold deposit occurred during the rollback of the subducting Paleo-Pacific Plate,which resulted in lithospheric thinning and the destruction of the North China Craton(NCC),which indicates that the deposit is of magmaticehydrothermal origin.  相似文献   

6.
The Hadamengou gold deposit is located in the western segment of the northern margin of the North China Craton (NCC). It is hosted by Archean metamorphic rocks of the Wulashan Group. The main ore types include gold-bearing quartz vein type, gold-bearing quartz-potassic feldspar vein type, and gold-bearing altered rock type. Gold mineralization is closely related to K-feldspathization. Hydrogen and oxygen isotope data indicate that ore-forming fluids were dominated by magmatic water mixed with minor meteoric water. Sulfur and lead isotope data indicate that metallogenic materials were mainly supplied by the magmatic and Archean Wulashan Group. The gold mineralization was mainly formed during the Early Indosinian tectonic movement, which drove ore-forming fluids to the favorable depositional environment. The northern margin of the NCC is a prospective area for gold exploration. Gold deposits hosted by or related to alkaline intrusions have become one of the most important mineral exploration targets in northern China.  相似文献   

7.
辽东地区金矿床类型、成矿特征及找矿潜力   总被引:3,自引:1,他引:2  
辽东地区是我国重要的金矿集区之一,中生代构造、岩浆活动强烈,并伴生强烈的金成矿作用。根据金矿床时空分布及成矿特征,将辽东地区划分为三个金矿集区:青城子、五龙、猫岭。矿集区内金矿包括石英脉型金矿和蚀变岩型金矿这两种类型,并分别受高角度断裂和低角度断裂构造体系控制。辽东地区金矿成矿时代主要为早白垩世,少量早侏罗世。已有H-O同位素、成矿流体及地质研究表明:(1)区内金成矿与中生代岩浆活动有关、受断裂构造控制,并以强烈硅化-绢云母化为特征标志;(2)区内金矿床属于岩浆热液型矿床;(3)充填作用和混合作用可能是辽东地区金矿床成矿物质沉淀的机制。辽东地区金矿成矿系统按其产出环境及特点,可分为两个亚系统:产于中生代花岗质岩体内岩浆热液金成矿系统(五龙式)及产于古元古代变质岩中岩浆热液金成矿系统(青城子式、猫岭式)。结合区域找矿进展和近期研究工作,建立了辽东地区金矿找矿预测地质模型,认为本区具有与胶东地区相似的金矿成矿条件,成矿潜力巨大,研究工作对区域矿产勘查部署工作有指导意义。  相似文献   

8.
罗山金矿床是胶东玲珑金矿田最大的金矿床之一,同时发育蚀变岩型矿化和石英脉型矿化。本研究在系统的野外和镜下工作基础上,利用电感耦合等离子体质谱(ICP-MS)技术分析了载金黄铁矿的微量和稀土元素,对比了蚀变岩型和石英脉型矿石载金黄铁矿稀土和微量元素特征,探讨了成矿流体的性质与来源。黄铁矿稀土总含量较低,多呈较明显的"右倾"式稀土配分模式,总体表现出负Eu异常,基本无Ce异常; Hf/Sm、Th/La、Nb/La值均<1,推断成矿流体为富Cl的还原性流体。Co/Ni比值范围在0. 08~3. 77,平均值为1. 09; Co/Ni值以及Co、Ni、Bi、Cu和Zn含量均与变质热液型金矿平均含量相近; Y/Ho比值范围总体在21~32之间,与中国东部大陆地壳Y/Ho比值(20~35)基本重合;结合个别样品的弱正Eu异常以及前人的研究成果,推断成矿流体与变质热液类似,主要来源于古太平洋板块俯冲板片脱水和脱碳作用,且可能有长英质岩浆流体和地壳流体的混入。蚀变岩型和石英脉型矿石内的载金黄铁矿的稀土、微量元素组成没有明显区别,Y/Ho、Nb/Ta和Zr/Hf比值变化范围均很小,表明两类矿石的载金黄铁矿为同一期热液活动作用的产物。  相似文献   

9.
高永宝  李文渊  李侃  钱兵 《矿床地质》2017,36(2):463-482
东昆仑祁漫塔格地区位于青藏高原北缘,为典型的大陆边缘增生造山带,经历了漫长的古生代—早中生代增生造山过程,其中以早中生代岩浆活动与成矿作用最为发育。文章系统总结了区内早中生代侵入岩分布及成因,对与其相关矿床地质、成矿流体特征及成矿物质来源进行分析,进一步探讨了祁漫塔格地区早中生代大陆地壳增生过程中的壳幔混合岩浆活动与成矿作用的关联。研究结果认为,中二叠世—早三叠世以俯冲阶段的侧向增生为主,中-晚三叠世以碰撞-后碰撞阶段的垂向增生为主,与成矿有关的岩浆岩主要为中-晚三叠世石英闪长岩、花岗闪长岩、二长花岗岩、正长花岗岩、花岗斑岩等,以I型、A型花岗岩为主,且多见暗色包体,Sr-Nd-Hf同位素组成表明其源于古陆壳物质的重熔,有地幔物质的参与,由地幔底侵古老陆壳,幔源基性岩浆与壳源花岗质岩浆发生不同程度混合作用而形成。与该时期岩浆活动关系密切的主要为斑岩型铜钼矿床、矽卡岩型铁多金属矿床、层控矽卡岩型铅锌矿床、与碱性花岗岩有关稀有金属矿化等。成矿时代集中于248~210 Ma,成矿流体主要来源于岩浆热液,成矿物质具有壳幔混合来源,区内中-晚三叠世大陆垂向增生过程中的壳-幔岩浆混合作用为区域大规模金属成矿提供大量热能、成矿流体及成矿物质。  相似文献   

10.
滇西北红山铜矿床成矿流体地球化学特征及矿床成因   总被引:6,自引:3,他引:3  
红山铜矿床为滇西北地区一大型斑岩-矽卡岩型铜多金属矿床,它产于印支期石英闪长玢岩及燕山期石英二长斑岩体内及其周边地层中,其形成经历了多期次热液叠加成矿作用过程.流体包裹体岩相学、显微测温及碳、氢、氧稳定同位素综合研究表明,矿区早期成矿流体为中高温、高盐度NaCl-H2O体系热液,主要来源于印支晚期岛弧型岩浆活动,对区内矽卡岩型矿化形成起了重要作用;晚期成矿流体为中高温、高盐度NaCl-CO2-H2O体系热液,主要来源于隐伏的燕山期后造山伸展型花岗质岩浆侵入体,形成了区内斑岩型Cu、Mo及相关的Pb、Zn多金属矿化.因此,红山铜矿床是两期岩浆热液叠加成矿作用结果.  相似文献   

11.
Abstract. The Baolun quartz vein type Au deposit, is located at the southwestern Hainan Island. It occurs next to a Triassic ilmenite-series/S-type syenogranite complex. A 40Ar/39Ar plateau age for muscovite from the master orebody is dated to be 219.4±0.6 Ma, suggesting that the gold deposit genetically related to the granite pluton. In the Baolun mining area, orebodies of auriferous quartz vein and wall rock alteration occur in NNW-striking fracture zones hosted by weakly metamorphosed turbidite of the Lower Silurian age. Eight fracture zones, 400∼1300 m long and 10∼30 m wide, have been identified. The five fracture zones of them form orebodies. The ores are mainly of quartz vein type. More than 20 orebodies in shapes of vein and lens of 195∼751 m in length and 0.20∼7.49 m in thickness are known, and 14 of them occur in the No. 1 vein belt. Silicification, sericitization and pyritization are closely related to the Au mineralization. The ores exhibit commonly 1.54∼29.48 g/t in Au grade, partially >98 g/t. The master orebody is 720 m long and 2.62 m thick in average, with 9.53∼29.27 g/t Au. Gold reserves of more than 70 t have been proven by geological exploration. More than 20 metallic minerals including native gold and sulfides such as pyrite, pyrrhotite, chalcopyrite, and others are identified to be formed in four ore-forming stages: (1) Au-coarse grain quartz stage, (2) Au-fine grained quartz stage, (3) Au-bismuthide-bismuth sulfosalt-sulfide-quartz stage, and (4) calcite-sulfide-quartz stage. The Au mineralization in this deposit occurred mainly in the first three stages. A variety of Bi- and Te-bearing minerals is closely associated with native gold suggesting that the mineralization may take place in a relatively high temperature.  相似文献   

12.
内蒙古达茂旗北部岩浆活动与铜、金成矿作用   总被引:2,自引:0,他引:2  
汤超 《地质与勘探》2013,49(2):224-235
内蒙古达茂旗北部岩浆岩分布广泛,以加里东期和华力西晚期为主。加里东期侵入岩以闪长岩、石英闪长岩及斜长花岗岩为主;华力西晚期侵入岩以闪长岩、石英闪长岩、黑云母花岗岩、二长花岗岩及钾长花岗岩为主。经研究发现,铜矿化多与闪长岩、石英闪长岩及花岗闪长岩有关;金矿化多与石英闪长岩、斜长花岗岩及黑云母花岗岩有关;铜、金矿床(点)均产于岩体内或其外接触带的火山岩中,暗示铜、金矿(点)的形成与岩浆活动密切相关。进一步研究发现本区铜、金矿化主要受华力西晚期岩浆活动控制。通过对研究区成矿地质背景的讨论及与斑岩型铜、金矿床地质特征的对比,指出本区具备寻找斑岩型铜、金矿床的潜力。  相似文献   

13.
河南西峡石板沟金矿成矿流体地球化学及矿床成因讨论   总被引:5,自引:2,他引:3  
张德会  刘伟 《现代地质》1999,13(2):130-136
石板沟金矿是近年在豫西南发现的一个剪切带容矿的脉状金矿。根据流体包裹体地球化学研究,分析了矿床成矿流体地球化学特征,讨论了金的沉淀机制和矿床成因。构造蚀变岩型金矿的形成主要与热液蚀变作用有关,石英脉型金矿的形成,则可能主要与岩浆热液与变质热液的混合作用有关。矿质主要源自晋宁期岩浆岩,成矿流体和热能主要来自海西期花岗岩。矿床为剪切带容矿的中低温热液金矿床。  相似文献   

14.
Gold deposits in intrusive masses include the veinlet dissemination,quartz vein and veinlet dissemination vein types,They are distributed in fracture zones along the endocontact zone of a batholith or in the centre and edge of a stock.The metallogenic epochs are Yenshanian,Hercynian,Archean,Proterozoic and Himalayan,The gold deposits are characterized by a big difference in time span between gold mineralization and the formation of host masses Ore-forming materials were derived from the masses and auriferous strata and ore-forming fluids came from meteoric and formation waters.When circulating water was heated by ascending heat flow,gold would be extracted,concentrated and transported from auriferous rocks and then precipitated in the masses during the late tectonic movement,Finally gold deposits were formed in the intrusive masses.  相似文献   

15.
刘屯金矿床为含金硫化物石英脉型,矿体直接围岩为晚太古代混合花岗岩。区域上建平群大营子组为金的矿源层,金成矿与中生代构造岩浆活动密切相关。含金石英脉(矿脉)严格地受近东西向断裂构造控制。据硫同位素组成证明矿石、围岩、中生代侵入岩具有同一性,为幔源硫。氢氧同位素组成则显示了成矿溶液的多成因特征。矿石中铅同位素为古老的铅体系,与中生代岩体的长石铅属同一源地。通过时矿床成因的探讨,认为是"岩浆热源-混合热液"型复成因金矿床,成矿时代为燕山期。  相似文献   

16.
吉林延边闹枝金矿床地质特征及矿床成因   总被引:2,自引:1,他引:1  
闹枝金矿床地处延边—东宁金矿带西段,为一主体产于海西期花岗闪长岩体内的石英脉型矿床。矿床地质特征及含金石英脉内流体包裹体研究结果表明,该区含金石英脉中主要发育气液两相及少量的含子矿物三相、气相--富气相包裹体。气液两相包裹体均一温度为283.5℃~375.9℃,盐度为3.4~8.13 wt%NaCl;富气相包裹体均一温度为416.5℃~431.6℃;含NaCl子矿物三相流体包裹体均一温度为303.9℃~393.2℃,盐度为38.21~45.3 wt%NaCl。包裹体氢、氧同位素分析结果表明,成矿流体以岩浆热液为主,可能混有少量大气降水。矿床成因属中温岩浆热液金矿床。  相似文献   

17.
宝兴沟金矿床为近年来在漠河前陆盆地南缘新发现的大型金矿床。区内发育石英闪长岩、闪长玢岩、花岗细晶岩等侵入岩,矿体主要产于石英闪长岩、闪长玢岩内部及其与二十二站组砂岩的内外接触带中。地球化学研究表明,石英闪长岩具高钾、低钛、富碱特征,花岗细晶岩具高硅、高钾、低钛、富碱特征,二者均为高钾钙碱性系列岩石,富集大离子亲石元素Rb、Ba、Sr等,亏损高场强元素Nb、Ta、Ti和重稀土元素Yb、Y,但二者稀土元素特征和配分曲线差异较大,不具成因联系。矿石与石英闪长岩、闪长玢岩具有相似的微量元素、稀土元素组成和稀土元素配分曲线,表明石英闪长岩、闪长玢岩为成矿提供了热液和成矿物质等,与成矿具有密切的成因联系。LA-ICP-MS锆石U-Pb同位素测年结果显示,石英闪长岩成岩时间为118.13~121.77 Ma,限定了宝兴沟金矿床的形成时间不早于118Ma,为早白垩世,形成于太平洋板块俯冲后的伸展环境。漠河前陆盆地除中-晚侏罗世侵入岩外,早白垩世中酸性侵入岩对区域成矿也具有重要的作用,是今后找矿的重要方向之一。  相似文献   

18.
尖尖石金矿成因类型为与岩浆岩有关的混合热液充填交代型金矿床。区内侵入岩主要为晋宁期闪长岩、石英闪长岩、斜长花岗岩以及混合质花岗岩。区内主要控矿构造为近南北一北西向的逆断层,断层性质为压扭断层,总体走向近南北向。断裂构造为矿质运移和矿质充填提供了通道和赋存空间。  相似文献   

19.
黑龙江金厂金矿田岩浆和成矿作用的LA-ICPMS锆石定年   总被引:4,自引:1,他引:3  
鲁颖淮  张宇  赖勇  王艳忠 《岩石学报》2009,25(11):2902-2912
黑龙江金厂金矿床为中亚造山带东段大型的浆控热液成矿系统,但成矿及其相关岩浆活动的时间研究薄弱.为厘定金厂金矿的形成时间和构造背景,本文利用单颗粒锆石激光探针LA-ICP-MS定年技术获得了赋矿花岗岩围岩和成矿闪长岩的锆石U-Pb年龄.结果表明,锆石韵律性环带结构发育,Th/U比值集中于0.5~1.5之间,具有岩浆锆石特征.两组锆石~(205)Pb/~(238)U谐和年龄分别为202.1±3.0Ma和111.5±1.2Ma,代表了两期岩浆.流体活动的时间;一组谐和性较差的蚀变花岗岩锆石~(206)Pb/~(208)U加权平均年龄为198.0±3.9Ma,指示赋矿花岗岩受到后期热液作用的影响而年龄偏小.据此认为,不同期次的岩浆-流体成矿事件在同一空间叠加复合是金厂大型金矿系统形成的重要原因;202Ma左右的岩浆一流体成矿事件缘于古亚洲洋闭合后大陆碰撞体制的岩浆作用,而111Ma左右的岩浆一流体成矿事件则缘于太平洋板块俯冲诱发的岩浆弧或弧后大陆伸展体制的岩浆活动.  相似文献   

20.
Mineral assemblages and chemical compositions of ore minerals from the Boroo gold deposit in the North Khentei gold belt of Mongolia were studied to characterize the gold mineralization, and to clarify crystallization processes of the ore minerals. The gold deposit consists of low‐grade disseminated and stockwork ores in granite, metasedimentary rocks and diorite dikes. Moderate to high‐grade auriferous quartz vein ores are present in the above lithological units. The ore grades of the former range from about 1 to 3 g/t, and those of the latter from 5 to 10 g/t, or more than 10 g/t Au. The main sulfide minerals in the ores are pyrite and arsenopyrite, both of which are divisible into two different stages (pyrite‐I and pyrite‐II; arsenopyrite‐I and arsenopyrite‐II). Sphalerite, galena, chalcopyrite, and tetrahedrite are minor associated minerals, with trace amounts of bournonite, boulangerite, geerite, alloclasite, native gold, and electrum. The ore minerals in the both types of ores are variable in distribution, abundance and grain size. Four modes of gold occurrence are recognized: (i) “invisible” gold in pyrite and arsenopyrite in the disseminated and stockwork ores, and in auriferous quartz vein ores; (ii) microscopic native gold, 3 to 100 µm in diameter, that occurs as fine grains or as an interstitial phase in sulfides in the disseminated and stockwork ores, and in auriferous quartz vein ores; (iii) visible native gold, up to 1 cm in diameter, in the auriferous quartz vein ores; and (iv) electrum in the auriferous quartz vein ores. The gold mineralization of the disseminated and stockwork ores consists of four stages characterized by the mineral assemblages of: (i) pyrite‐I + arsenopyrite‐I; (ii) pyrite‐II + arsenopyrite‐II; (iii) sphalerite + galena + chalcopyrite + tetrahedrite + bournonite + boulangerite + alloclasite + native gold; and (iv) native gold. In the auriferous quartz vein ores, five mineralization stages are defined by the following mineral assemblages: (i) pyrite‐I; (ii) pyrite‐II + arsenopyrite; (iii) sphalerite + galena + chalcopyrite; (iv) Ag‐rich tetrahedrite‐tennantite + bournonite + geerite + native gold; and (v) electrum. The As–Au relations in pyrite‐II and arsenopyrite suggest that gold detected as invisible gold is mostly attributed to Au+1 in those minerals. By applying the arsenopyrite geothermometer to arsenopyrite‐II in the disseminated and stockwork ores, crystallization temperature and logfs2 are estimated to be 365 to 300 °C and –7.5 to –10.1, respectively.  相似文献   

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