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1.
<正>抱伦金矿床位于中国海南省西南部乐东县境内,是一个大型中温热液金矿床。该矿床以含金石英脉为主,蚀变岩型金矿脉次之。金矿脉呈NNW方向分布在志留系浅变质碎屑岩破碎带之中。68个矿石样品的多元素分析结果表明抱伦金矿床具有富Bi高Au的特点,属于Au-Bi-(低Te)-S流体体系。抱伦金矿床的金属矿物有自然金、黑铋金矿、硫铋金矿、自然铋、辉铋矿、辉铅铋矿、斜方辉铅铋矿、硫碲铅矿、硫铋碲矿,伴生矿物以磁黄铁矿、毒砂、黄铜矿为主,还有Fe-闪锌矿、方铅矿、黄铁矿等,脉石矿物主要  相似文献   

2.
陈武  薛纪越 《地质论评》1965,23(5):409-411
斜方辉铅铋矿零星地分布于赣南某些钨锡石英脉矿床中,有时可在个别矿床局部富集。以往本区一般把斜方辉铅铋矿描述成辉铋矿,并常谈到辉铋矿和方铅矿的共生。根据我们在野外对几个钨锡石英脉矿床中所采集的标本和经过室内的矿物鉴定,认为前人所指的辉铋矿矿物中的一部分矿物是斜方辉铅铋矿。  相似文献   

3.
河南公峪石英脉型金矿地质特征及应力场分析   总被引:1,自引:0,他引:1  
公峪金矿位于河南省祁雨沟隐爆角砾岩型金矿床的外围,为石英脉型金矿床,矿脉沿NNE、NE,NEE向断裂构造发育。矿石中金属矿物除黄铁矿、自然金、黄铜矿、方铅矿外,还出现少量碲铋矿,辉蹄铋矿,硫铋铅铜矿等含铋矿物;矿石中微量元素除Au外,还含有较多的Cu,Pb,Ag,与隐爆角砾岩型金矿床成分特征一致。构造应力场研究表明,燕山期以来,在矿区表现较强的应力场主要有3期,分别为早期近EW向挤压,中期NNW向  相似文献   

4.
东昆仑夏日哈木超大型岩浆镍钴硫化物矿床的工业价值,不仅取决于矿石中Co、Ni的含量,还取决于钴和镍关键金属的赋存状态和分布规律。笔者利用全自动矿物分析系统钻孔样品分析,确定Co和Ni在样品中有2种赋存状态:独立钴、镍矿物和含Co、Ni矿物。对钴、镍金属矿物进行原位主、微量元素分析发现,Co在钴、镍金属矿物中含量由高到低为:辉砷钴矿>砷镍矿、方硫铁镍矿、镍黄铁矿>红砷镍矿、磁铁矿>磁黄铁矿、黄铜矿;Ni在钴、镍金属矿物中含量由高到低为:砷镍矿、红砷镍矿>硫铋镍矿、方硫铁镍矿、镍黄铁矿>辉砷钴矿>磁铁矿、磁黄铁矿、黄铜矿。选择钻孔中体积分数占比最高的磁黄铁矿、镍黄铁矿和黄铜矿,进行原位核–边微量元素及面扫描分析发现,Co、 Ni在镍黄铁矿和黄铜矿单颗粒尺度上是均一分布的,两种矿物的Co/Ni值变化不大,表明矿物没有受到热液作用影响。然而,Ni在磁黄铁矿中分布不均一,并且矿物的Co/Ni值变化较大,表明磁黄铁矿对热液作用更为敏感。矿物原位主、微量元素分析结果显示,镍黄铁矿中的Co、Ni含量与镍、钴独立矿物接近,远超岩体中其他含钴、镍金属硫化物。因此,含Ni...  相似文献   

5.
我国南部一钨鉍石英脉中的含铋矿物   总被引:1,自引:0,他引:1       下载免费PDF全文
任英忱 《地质科学》1965,6(2):172-181
过去对我国南部钨鉍石英脉中的含鉍矿物的专门研究资料比较罕见。一般报告、文献中都将铅灰色、柱状的矿物认作为辉鉍矿;而在矿相工作中将反射率高、具淡黄色调的细小含鉍包裹体大部分都鉴定成为自然鉍,这与事实是有出入的。经研究表明:以前认作的辉鉍矿当中,除辉鉍矿外还有铅辉鉍矿、辉铅鉍矿、斜方辉铅鉍矿等;而前人认作的自然鉍则包括的更多,有碲鉍矿A、碲鉍矿B、多碲鉍矿、辉碲鉍矿等碲的独立矿物。这些矿物的发现,无疑将有利于矿石的综合利用,同时也为解释成矿过程中碲、硒、鉛、铅等元素的地球化学特性,提供了有意义的资料。  相似文献   

6.
本区金矿床的成因与晚中生代花岗岩类有关,分布范围广泛,分为3种类型:矽卡岩型、云英岩型及稀有金属石英脉型。矿体以脉状、网脉状、浸染状、块状等多种形式出现,在矿石中早期金多与铁、镍、钴的硫砷化物、砷化物紧密共生,晚期金则与含铋矿物共生(自然铋、辉铋矿、脆硫铋矿、碲化物和硫碲化物)。矿石中金为细粒金和次显微金;在矽卡岩型及云英岩型金矿石中,粒径小于0.1mm的金占总量的90%,而在稀有金属石英脉型金矿  相似文献   

7.
江西盘古山石英脉型钨矿床流体包裹体研究   总被引:14,自引:0,他引:14  
采用"流体包裹体组合"(FIA)的方法,在详细的岩相学观察的基础上,对盘古山钨矿床主要矿化阶段中早阶段的辉铋矿-黑钨矿-石英脉和晚阶段的(辉铋矿)-黑钨矿-石英脉石英中的流体包裹体进行了显微测温和拉曼探针的分析。该矿床主要矿化阶段含矿石英脉中包裹体主要包括H2O-NaCl型包裹体、H2O-NaCl-CO2型包裹体和少量的CO2型包裹体,富含CO2组分是盘古山钨矿成矿流体的明显特征。实验结果表明,矿床中主要矿化阶段石英脉中两相的H2O-NaCl型包裹体与H2O-NaCl-CO2型包裹体主要均一温度范围较为一致而前者盐度相对较高。辉铋矿-黑钨矿-石英脉中的H2O-NaCl型包裹体的均一温度明显高于(辉铋矿)-黑钨矿-石英脉中的H2O-NaCl型包裹体,但两者的盐度相差不大,从辉铋矿-黑钨矿-石英脉到(辉铋矿)-黑钨矿-石英脉,H2O-NaCl-CO2型包裹体数量减少,CO2型包裹体数量增多。对各类包裹体的激光拉曼探针测试表明,辉铋矿-黑钨矿-石英脉中和(辉铋矿)-黑钨矿-石英脉中的包裹体的组分相近,除水和CO2外,还含有少量的CH4和N2。盘古山钨矿的流体包裹体特征表明,以CO2逸失为特征的流体不混溶作用是矿床金属沉淀的主要机制。  相似文献   

8.
新嘎果矿床是西藏冈底斯成矿带北缘矽卡岩多金属成矿带的一个典型矽卡岩型铅锌矿床。矽卡岩矿体主要呈层状、似层状产于下白垩统塔克那组地层中。电子探针测试结果表明,矽卡岩矿物主要为钙铝榴石、钙铁辉石和绿帘石,少量的硅灰石、密绿泥石等,构成典型的钙质矽卡岩。金属矿物主要为闪锌矿、方铅矿、磁黄铁矿、黄铜矿、黄铁矿,少量的白铁矿、毒砂、自然铋、斜方辉铅铋矿、辉砷镍矿等。该矿床中石榴子石成分特征指示成矿环境是变化的,在早期进变质阶段由氧化环境向还原环境转变,而晚期退变质阶段由氧化环境向还原环境转变。金属矿物中闪锌矿主要为铁闪锌矿,表明其形成于中高温环境。而含铋的矿物主要为自然铋、斜方辉铅铋矿和方铅矿,并且在这些矿物中Ag和Bi的含量呈正相关性,指示铋对银的富集可能起着重要的作用;此外,铋也是新嘎果矿床重要的伴生有用元素,具有较高的综合利用价值。  相似文献   

9.
辽宁五龙金矿铋矿物与金矿化关系研究   总被引:6,自引:0,他引:6  
赵玉山  金成洙 《矿物学报》1994,14(1):88-91,T001
辽宁五龙金矿的铋矿物为辉铋矿,自然铋和辉铅铋矿,它们与金矿化关系非常密切,在高温条件下,Bi与Au呈固溶体形式或某种化合物形式存在,随着温度的下降,Bi与Au分离构成两种独立矿物,二者紧密共生,在含金石英矿体中,铋矿物的多少直接影响矿石品位,铋矿物是重要的金矿化指示矿物。  相似文献   

10.
湖南浏阳七宝山多金属矿床中的辉碲铋矿   总被引:1,自引:0,他引:1  
一、地质产状和共生组合 辉碲铋矿是一种产量少,但比较普遍的矿物。主要产于中温至高温含金石英脉或黄铜矿-斑铜矿-辉铜矿矿脉中。在接触交代矿床中也偶尔见到。常见辉碲铋矿与多种硫化矿物共生。 我们在研究湖南浏阳七宝山矽卡岩-热液多金届矿床时,发现辉碲铋矿产于磁铁矿矿石内,与磁铁矿共生。出熔的辉铋矿呈叶片状沿辉碲铋矿的解理分布。自然金分布在辉碲铋矿的晶面上。  相似文献   

11.
成矿系统嵌套分形结构和自有序效应   总被引:10,自引:0,他引:10  
成矿系统具有嵌套分形结构 ,岩石孔隙结构的传输性质制约着聚矿功能的实现。矿床(脉 )群聚分形分布特征明显 ,数量随时代先后呈幂律增长 ,成矿裂隙系统分维值大 ,高含量矿脉分维值低 ,这为隐伏矿床 (体 )预测提供了依据。裂隙生长是一种自组织临界现象 ,矿脉起源于微裂隙发展而成的张性裂隙 ,并最终形成脉系。超大型矿床的裂隙系统表现为临界分维状态 (5~ 12 5km ,D≈ 1 5;0 5~ 2 0km ,D≈ 1 3;1~ 10 0cm ,D≈ 1 5;0 0 0 36~ 0 18cm ,D =1 2 8~1 39)。成矿元素运移通过扩散和渗流实现 ,扩散速率的差异性导致运移路径的有序性 ,流体流动导致金及金属硫化物在界面处发生反应而沉淀成矿 ,矿床密度分布随矿化中心距离增大而减小的自有序效应保证了成矿系统的组织层次性。输运反应耦合成矿动力学计算机模拟验证了分形脉体演化模式和自有序效应。  相似文献   

12.
The ore deposits of The Granites goldfield are shear-hosted within Palaeoproterozoic amphibolite facies metasedimentary rocks in the Tanami Region, Northern Territory, Australia. The ore bodies are located within a 5- to 35-m thick sequence of steeply dipping unit of metamorphosed iron-rich metasedimentary rocks. Deformation at The Granites was complex and is characterized by five successive deformation phases (D1–5). Shear veins (central and oblique) are the dominant type of vein geometry, with minor development of extensional veins and reverse-fault related veins. Four generations of syn-tectonic veins, corresponding to D1, D3, D4, and D5, have been recognized and are comprised of quartz, quartz-carbonate, calc-silicate, and calcite. In addition, two generations of disseminated sulfide–arsenide mineralization, dominated by pyrrhotite, arsenopyrite, and loellingite, with minor pyrite, chalcopyrite and rare marcasite, formed syn-D1 and syn- to post-D3. Textural and structural evidence indicates deposition of gold was contemporaneous with the syn-D1 veins and sulfide–arsenide mineralization. Four hydrothermal phases are proposed for the formation of the veins and disseminated sulfide–arsenide assemblages. The first phase (D1) was responsible for transport and deposition of the majority of the gold. Minor remobilization and deposition of gold occurred during the D3 and D4 phases. Little is known about the nature of the D1 ore fluid, although a relatively low sulfur content is indicated by the assemblage pyrrhotite–arsenopyrite–loellingite+rare pyrite. The growth of amphibolite facies metamorphic minerals andalusite and almandine garnet during D1 indicates a high temperature for the fluid. The D3 hydrothermal phase coincided with peak metamorphism. D4 fluids were hypersaline, high temperature, CO2-poor, and H2S-poor. Editorial handling: L. Meinert  相似文献   

13.
2003年在广东大亚湾西北部新发现了一处火山岩型铀矿点,经刻槽取样分析,铀矿石品位高达0.459%。该处铀矿物成份主要是沥青铀矿和次生铀矿物,前者 UO_2最高为94%,Al_2O_3<1%,P_2O_5含量变化大,按照 P_2O_5含量可分两组,其一变化于2.23%~2.57%,另一组变化于17.96%~19.95%;次生铀矿物含 UO_3大约为60%左右,Al_2O_3在1.6%~3.0%之间,P_2O_5变化于10%~15%。对含矿岩石及围岩进行了岩石学和地球化学研究,结果表明,出露的岩石主要为流纹质岩石,与著名的相山矿田的岩石类型相似。岩石具有高的 LREE/HREE 值,Eu 负异常并不普遍。从主、微量元素及稀土元素特征来看,含矿岩石及围岩差别不大,总特征与一般的钙碱性火山岩相似。新发现的铀矿化带范围虽然不大,但含矿岩石铀品位高,所处构造环境与相山铀矿田的某些矿床有一定的相似性,是值得注意和进一步工作的地区。  相似文献   

14.
The southwestern Sabzevar basin is the north of Central Iranian Microcontinent hosts abundant mineral deposits, including exhalative Mn mineralization and Cu-Zn volcanogenic massive sulfide (VMS) deposits. Amongst them, the Nudeh Besshi-type Cu–Zn volcanogenic massive sulfide (VMS) deposit is hosted within the lower part of a Late Cretaceous volcano-sedimentary sequence composed of alkali olivine basalt flows and tuffaceous silty sandstone. Based on investigations into the ore geometry, mineralogy, and texture, we recognized three different ore facies: (1) a stockwork of sulfide-bearing quartz veins cutting across the footwall volcano-sedimentary rocks and representing the stringer zone; (2) a massive ore type, displaying replacement texture with pyrite, chalcopyrite, sphalerite, friedrichite, and minor magnetite; and (3) a bedded ore type, with laminated to disseminated pyrite and chalcopyrite. EPMA studies indicate a distinctive minor element distribution between the different ore types of the Nudeh deposit. The Fe content in the sphalerite ranges from 0.65–1.80?wt.%, indicating the Fe-poor nature of the sphalerite. However, the Cd content in sphalerite ranged between 0.164–0.278?wt.%. According to the mineral compositions, Zn, Se, and Ag are found in bornite as minor elements. In the bedded ore facies, the pyrite contains higher levels of Se (up to 0.35?wt.%). The Zn content in the friedrichite in all of the ore samples is low. The Co/Ni ratios in pyrite from the Nudeh ore are lower than those of most magmatic deposits, but are similar to those from volcanogenic deposits, and hence support the proposed hydrothermal origin of the deposit. Two generations of quartz, Q1 and Q2 in the stockwork veins, contain primary fluid inclusions and these contain two phases (liquid and vapor). The lack of vapor-rich inclusions or variable liquid/vapor ratios indicate that the fluids did not boil at the site of trapping. Salinity for both Q1 and Q2 fluid inclusions ranges between 2.2–6.8?wt.% eq. NaCl. Homogenization temperatures for inclusions in the Q1 and Q2 veins average at about 296?°C and are similar to the temperatures of hydrothermal fluids discharged through vents in many modern seafloor VMS deposit. The Nudeh Besshi-type VMS deposit appears to have formed on the seafloor and based on the salinity and temperature constraints from the underlying stockwork, a buoyancy plume model is proposed as a mechanism for precipitation.  相似文献   

15.
In the Noril’sk ore field, parkerite is a characteristic mineral of sulfide ore that metamorphosed under conditions of zeolite and prehnite-pumpellyite facies and of arsenide-calcite veins. The mineral occurs in ores containing bornite, anhydrite, magnetite, mackinawite (3–5 wt % Ni), valleriite, calcite, ankerite, native silver, native bismuth, violarite, Te-rich bismutohauchecornite, cupropentlandite enriched in Fe, Pd-rich breithauptite (1.5–2.5 wt % Pd), galena enriched in Cu (3.8 wt % Cu), and Ni arsenides and antimonides. Parkerite occurs in those place, where the primary ores have contained pockets and veins of graphic galena and chalcopyrite aggregates with associated Pt-Pd-Au-Ag minerals. Parkerite metacrysts in galena and Fe-Cu-Ni sulfides contain 6–16 and up to 5 wt % Pb, respectively. Parkerite rims replacing PGM aggregates and galena contain 1–3 wt % Pb. In calcite veins hosted in metamorphosed sulfide ores, parkerite is associated with native silver and bismuth, maucherite, cobaltite, chalcocite, and uraninite. Parkerite from these veins contains up to 0.5 wt % Pb. Thus, the Pb and Bi contents in parkerite basically depend on those of replaced minerals. Rare bismutohauchecornite is associated with parkerite.  相似文献   

16.
本文讨论了龙门山造山带中段上孟—漩口一线石英方解石脉的微量元素地球化学特征。结果表明:与方解石相比,石英杂质元素总量很低,特别是稀土元素含量远低于方解石,但K、Na、Cr、Co、Th 等则变化不大;石英与方解石均富集重稀土;石英与方解石的稀土元素配分型式总体相似,暗示其来源之间有一定的联系;石英和方解石脉均有强的铕正异常,不同层位的样品铕正异常强度不同,指示围岩条件的差异及形成条件的影响。  相似文献   

17.
刘军  靳淑韵 《中国地质》2010,37(2):324-333
弓长岭二矿区既是大型条带状铁矿床,同时又是大型磁铁富矿床,自1949年建矿以来,一直是鞍钢的主体矿山和高品位富矿的主要供应地。笔者在总结矿床地质特征的基础上,对矿区的主要变质岩-斜长角闪岩类的主量元素、微量元素和稀土元素进行了分析。结果显示:主量元素的平均化学成分与基性火山岩中玄武岩成分相似,MgO和CaO含量比较高,而且Na2OK2O;微量元素:相容元素Sc、V、Cr、Co、Ni、Cu的含量比较高,属于右倾型;(Rb/Yb)N值为5.95~132.93,平均值为49.34,远远大于1,为强不相容元素富集型;大离子亲石元素Rb、Ba、K、Sr明显富集,但Th、U强亏损;高场强元素中Zr、Hf明显富集,而Nb、P为中等亏损,Ti为弱亏损,与亏损型洋中脊拉斑玄武岩很相近;稀土元素具有∑REE低(21.09×10-6~69.13×10-6,平均40.44×10-6)、LREE略有富集(LREE/HREE=1.70~2.58,平均2.27;(La/Yb)N:0.93~4.27,平均值1.60)的稍右倾型或平坦型特征。轻稀土分馏不明显((La/Sm)N:0.87~3.28,平均值1.42)。根据主量、微量和稀土元素的特征,并结合环境构造判别图解,笔者认为,研究区斜长角闪岩的原岩为大洋中脊拉斑玄武岩。  相似文献   

18.
The Rajkonkoski ore occurrence is located within the region of the Karelian craton (AR2) and the Svecofennian folded belt (PR1) conjugation. It is presented by quartz-carbonate veins in metadoleriles and a zone of brecciation, crumple, and silification of carbonaceous shales within the volcanites of the Soanlakhtinsky suite (PR1). Ore mineralization in black shales and quartz veins has features of genetic similarity presenting different levels of the ore system controlled by different range strike-slip fault dislocations. At the Rajkonkoski ore occurrence, 41 ore minerals have been identified: 12 tellurides (native tellurium, hedleyite, pilsenite, tsumoite, tellurobismuthite, hessite, stuetzite, radclidzhite, joseite-B, altaite, volynskite, petzite); 4 bismuth-tellurides of the following compositions Bi3Te, Bi3Te2, BiTe4, PbBiTe; 3 selenides (clausthalite, tellurolaitakarite, native selenium); and 12 native metals (gold, silver, electrum, copper, iron, lead, tin, bismuth, osmiridium). The contents of the main ore minerals in places exceed 10%, and the concentrations of elements reach as follows: Cu and Pb, 5%; Zn, Bi, 1%; Se, 219 ppm; Te, 171 ppm; Sb, 3 ppm; As, 5 ppm; Ag, >0.1%; Au, 35.28 ppm. Ore mineralization is formed during the temperature interval from 550°C up to <170oC in the conditions of high activity of Se and Te, and beginning from medium temperatures (>300°C) complete miscibilities galenite-clausthalite and galenite-altaite are observed. In aggregate with a wide temperature interval (>400°C) of ore process evolution and mineral specia variety of telluride and native metal mineralizations, the original “torsion” of different temperature mineralizations makes it possible to determine the affiliation of the Rajkonkoski ore occurrence to the xenothermal type deposits or epithermal “alkaline,” gold-telluride A-type characterized by a close connection with magmatism of increased alkalinity and the original geochemical (Te-V-F) and mineral (tellurides of gold, silver and other metals, fluorite, roscoelite, vanadium-containing sulfides) associations. Taking into consideration that many of the xenothermal and epithermal A-type gold and silver deposits are large commercial objects, the prospects of the Rajkonkoski ore occurrence and the region of the Karelian craton and Svecofennian folded belt conjugation seem to be significant for noble metal mineralization.  相似文献   

19.
张志远  谢桂青  袁亮 《岩石学报》2023,(6):1847-1860
湘中是全球最大的锑金矿集区,近年来又陆续探明了一批钨矿床,但这些钨矿和锑金矿之间的关系目前尚不明确。曹家坝钨矿床是目前该矿集区内规模最大的钨矿床(19.03Mt@0.37%WO3),矿体与矽卡岩密切共生,成矿作用划分为矽卡岩阶段、退化蚀变阶段和石英-白钨矿-硫化物阶段。不同阶段白钨矿δ18OV-SMOW变化范围为6.0‰-7.9‰,δDV-SMOW变化范围为-79.1‰--68.9‰,对应的δ18OH2O变化范围为3.3‰-5.2‰。白钨矿(87Sr/86Sr)t变化范围为0.72215-0.73049,εNd(t)变化范围为-12.8--10.6。龙山锑金矿床是矿集区内发育的大型脉状锑金矿床(4.2Mt@3.4%Sb和3.7g/t Au),矿体赋存在震旦系江口组板岩中,发育两个世代的白钨矿与辉锑矿共生。白钨矿δ18OV-SMOW变化范围为5.4‰-9.0‰,δDV-SMOW变化范围为-72.9‰--60.2‰,对应的δ18OH2O变化范围为3.1‰-6.7‰。Sr-Nd-H-O多元同位素特征显示,曹家坝钨矿床的成矿物质和成矿流体以岩浆来源为主,龙山锑金矿床有岩浆流体参与成矿,两者均有少量板溪群基底地层和大气降水的加入。综合本次及前人研究成果,曹家坝钨矿床和龙山锑金矿床具有成因联系,二者均是湘中矿集区晚三叠世岩浆热液W-Sb-Au成矿系统的重要组成部分。  相似文献   

20.
Abstract: The Dongping deposit, located near the center of the northern margin of the north China craton, is one of the largest gold deposits in China. It is spatially, temporally, and genetically associated with the shallowly-emplaced Hercynian Shuiquan-gou alkaline intrusive complex. The complex intrudes high-grade metamorphic rocks of the Archean Sanggan Group along a deep-seated fault zone within the north China craton. Four major ore bodies (Nos. 1, 2, 22, and 70), consisting mainly of a set of en echelon lenses and veins, have been delineated at the Dongping deposit. Hypogene hydrothermal activities can be divided into four periods from early to late including: (1) gold-bearing K–feldspar–quartz stockworks and veins; (2) disseminated sulfide and gold zones; (3) gold-bearing quartz veins, and (4) barren calcite-quartz veins. Individual veins and stockwork systems can be traced along strike for 125 to 600 m and downdip for 100 to 600 m; they range from 0. 5 to 3 m in thickness. The mineralogical composition of the ore in the first three hypogene periods is relatively simple. It is composed of pyrite, galena, sphalerite, magnetite, specularite, chalcopyrite, native gold, electrum, calaverite, and altaite. Gangue minerals include K–feldspar, quartz, sericite, chlorite, epidote, albite, and calcite. Ore grade averages 6 g/t Au, but varies between 4. 14 and 22. 66 g/t Au. Gold is generally fine-grained and not visible in hand specimen. Fluid inclusions in ore-bearing quartz of periods 1, 2, and 3 are CO2–rich, variable salinity (2. 5–21 wt% equiv. NaCl), and have variable homogenization temperatures of 195° to 340°C. Quartz in the gold-bearing K–feldspar–quartz stockworks (period 1), disseminated sulfide and gold zones (period 2), and the gold-bearing quartz veins (period 3) has calculated δ18OH2O values between –1. 7 and 6. 9%, and δ values of fluid inclusion waters between –101 and –66%. All these isotope data of the ore-forming fluids plot between the magmatic fluid field and the meteoric water line. Sulfide minerals disseminated in host rocks show positive δ34S values of 1. 9 to 3. 5%. Pyrite separates from he gold-bearing K–feldspar–quartz stockworks and veins (period 1) have a δ34S range of –4. 3 to 0. 5%, whereas δ34S values of pyrite, chalcopyrite, galena, and sphalerite from the disseminated sul-fide and gold zones (period 2) and the gold-bearing quartz veins (period 3) vary from –5. 3 to –13. 4%. Gold ores are also characterized by relatively radiogenic lead isotope compositions compared to those of the alkaline syenite host rock. The data are interpreted as indicative of a mixing of lead from the alkaline intrusive complex with lead from Archean metamorphic rocks. The combined fluid inclusion measurements, sulfur, oxygen, hydrogen, and lead isotope data, and petrological observations indicate that the Dongping deposit was formed from the mixing of these magmatic fluids with meteoric waters. The deposit is, therefore, believed to be a product of Hercynian alkaline igneous processes within the north China craton.  相似文献   

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