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1.
By means of microscopy and laser Raman spectroscopy,the authors studied the fluid inclusions in petrography.The results show that there exist three-phase CO2 -bearing and two-phase aqueous inclusions in gold ore;the fluid of NaCl-H2O--CO2 system went through immiscibility in ore-forming process.Ore-forming fluids were of low salinity(0.82%-5.40%NaCleqv),low density(0.54-0.93 g/cm3);mineralization tempera-ture were concentrated in 320℃--340℃,with ore-forming pressure in 62-126 MPa and mineralization depth in 6.34-9.35 km.The fluid inclusions in quartz are generally characterized by a small amount of CO2 and N2.Combined with recent results of the isotopic analysis for fluid inclusions and dating data,it was indicated that the main ore-forming fluids derived mainly from source of mantle-derived fluids with a small amount of magmatic fluid and meteoric water.The genetic type was mesothermal gold deposits involved by mantle-derived fluids.  相似文献   

2.
The South Narimalahei area is located on the north side of the Middle Kunlun fault in the eastern section of the East Kunlun composite orogenic belt. The ore body is veined and controlled by structures and se-condary fissures, which occurs in the structural alteration fracture zone in the Late Triassic granodiorite. In this deposit, copper mineralization is closely related to silicification and sericification. The formation process of the deposit includes hydrothermal mineralization and supergene oxidation. In this paper, the fluid inclusion minera-logy, microscopic temperature measurement and stable isotope studies have been carried out for ore of the main mineralization stage. The results show that the primary gas-liquid two-phase inclusions and a small amount of single-liquid inclusions are mainly developed in the quartz in the main mineralization stage. The results of microscopic temperature measurement show that the ore-forming fluid which has low temperature(151.7℃--205.8℃), low salinity(2.06 wt%--4.94 wt%NaCl), low density(0.86--0.92 g/cm~3) and shallow formation(1.5--3.0 km) is a hydrothermal solution of NaCl-H_2O system. Hydrogen and oxygen isotope results show that the ore-forming fluids mainly come from atmospheric precipitation, with a small amount of magmatic fluids participating. It is preliminarily determined that the South Narimalahei copper polymetallic deposit is a low-temperature hydrothermal vein deposit.  相似文献   

3.
the Sishanlinchang gold-silver deposit is mainly composed of gold-quartz vein type ores.It has many kinds of sulfides and gold in high grade.The Au has a close correlation with As,Pb,Ag and Cu.Geochemically,the deposit is characterized by relatively enrichment in LREE with moderate or lower Eu negative anomaly.Sulfur isotopes appear as single and deep source,and lead isotopes indicate the Pb is from the earth’s mantle and crust,which mainly are orogenic belt Pb,the ore-forming fluid has a temperature of 215℃-350℃ and a low salinity with a mixture of characteristics of magmaitc hydrothermal and meteoric water.The ore-forming age is 111.1-111.4 Ma.The deposit is formed in mineralization and precipitation of metallogenic materials caused by the mixture of the magmatic hydrothermal fluid and meteoric water.  相似文献   

4.
通过对含金石英脉中矿物包裹体的研究,探讨了文峪金矿形成的物理化学条件,指出文峪金矿是在地表较浅部位形成的中-低温热液型矿床,其成矿母液为低盐度Na-Ca-Cl-CO2系列热液流体。运用了包体测温和包体化学成分以及盐度、密度等资料,对该矿进行了深部成矿预测,认为文峪金矿深部有宫金矿体存在,具有广阔的找矿勘探前景。  相似文献   

5.
湖北铜绿山铜铁(金)矿床是长江中下游地区典型的矽卡岩型矿床。为了探究其矽卡岩的成因,进行了包裹体的岩相学观察,显微测温和激光拉曼分析。研究结果表明,铜绿山矿床流体包裹体的均一温度为180~700℃,盐度w(NaCleqv)为1.74%~55.7%;从矽卡岩期到石英—硫化物期,成矿流体从高温、高盐度向低温、低盐度演化;激光拉曼显示熔融包裹体中包含石榴石、方解石、赤铁矿和水。综合包裹体的岩相学及相组成特征,铜绿山矿床的早期矽卡岩应为岩浆成因。   相似文献   

6.
The Diakha gold deposit is located in the southeastern margin of the highly prospective/productive Paleoproterozoic( Birimian) Kédougou-Kéniéba Inlier. Gold mineralization is closely associated with a narrow,sub-vertical,NE-trending shear corridor. The corridor is to the east of a sinistrally reactivated D1 west-dipping fault,which emanated from SMSZ( D2 reverse-sinistral regional structure). The mineralization is hosted by fine-grained sandstone and breccias units associated with a moderate to strong hydrothermal alteration,which is dominated by albitization,carbonization,silicification,hematization,and chloritization. Diakha field data and laboratory analysis suggest the existence of two main stages of hydrothermal mineralization,namely stage I and stage II. Stage I is of a breccias type of mineralization and represents the major gold bearing stage. It isassociated with hematite + calcite + ankerite/dolomite and quartz pervasive alteration,controlled by the predominantly brittle-ductile NNE to NE-shearing structures of the main deformation event D2. Stage II is represented by the second minor hydrothermal episode,showing local quartz-tourmaline and tremolite alteration which is structurally controlled by the dipping S3 cleavage formed during D3 deformation. Petrographic and microthermometric studies of fluid inclusions from quartz veins reveal the presence of early dominant carbonic CO2-pure and aqueous-carbonic CO2-rich( LCO2+ VCO2± H2 O) in stage I. The exclusively aqueous H2 O + Na Cl ± CO2 fluid inclusions( L-type) are observed in stage II. Interpretation shows that the ore-forming fluids originated from a homogeneous H2 O-CO2 fluid during phase separation,with trapping temperatures of 250℃ to 280℃ and low salinity( 6 wt % Na Cl equiv),indicating an estimated trapping pressure for the deposit between 610 to 800 bars.  相似文献   

7.
贾公台金矿床是秦祁昆造山系南祁连党河南山地区最具代表性的金矿床之一。为了查明其矿床成因类型,对贾公台金矿床进行矿床地质特征的系统性研究和成矿主阶段流体包裹体的测温及激光拉曼测试分析。结果表明:矿床位于NW向与NE向构造的交汇部位,矿化产于下奥陶统上岩组浅变质海相碎屑岩和花岗岩中,严格受NW向断裂控制;矿体主要呈脉状、透镜状,Au品位较高(1.98×10-6),有害组分少,且伴生Ag;成矿主阶段流体包裹体类型为气液两相包裹体及少量气体包裹体;成矿流体为低盐度、低CO2含量的NaCl-H2O体系,成矿温度为236℃~245℃(中温),成矿压力为48.7~51.4MPa,对应深度为5.56~5.72km;经与浅成热液型金矿、造山型金矿主要特征进行对比,初步厘定贾公台金矿床为浅成热液型金矿床。  相似文献   

8.
通过湖南部分金锑矿床年代学特征研究表明,170~150 Ma为华南集中成矿的高峰期,谢家山金锑矿通过白云母Ar-Ar测得成矿年龄160±2 Ma,受燕山运动Ⅰ影响,剧烈的构造作用与岩浆活动为成矿作用提供了动力学基础和储矿空间。流体包裹体地球化学、硫同位素和氢氧同位素的研究表明,谢家山金锑矿的成矿流体显示中低温(153.8~270.0℃)、低盐度(0.88~5.71%)、低密度(0.90~0.95 g·m~(-3))的特征。换算出其成矿压力范围是50~100 MPa,计算成矿深度为1.82~3.78 km,显示矿床成矿深度不大。该矿形成于中低温、低压环境条件下,成矿溶液主要为大气降水,早期伴有深源物质,并经历了多期次的构造与变质作用。谢家山金锑矿属矿床成因应该属于沉积—变质热液充填金锑矿床。  相似文献   

9.
新疆阿尔泰铁矿成矿流体及成矿过程   总被引:2,自引:0,他引:2  
以新疆阿尔泰铁矿为研究对象,综述铁矿成矿背景,划分成因类型和成矿时期,对典型矿床地质特征进行描述,研究成矿流体的温度和盐度以及成矿流体来源,最后探讨构造演化与铁矿成矿作用。结果表明:铁矿成因类型可划分为火山岩型、矽卡岩型、伟晶岩型、与花岗岩有关的热液型、与基性岩体有关的钒钛磁铁矿型和砂矿型;矽卡岩矿床流体包裹体从矽卡岩阶段到退化蚀变阶段再到石英-硫化物-碳酸盐阶段的均一温度(从200℃~500℃到200℃~350℃,再到160℃~300℃)以及流体盐度(NaCleq)峰值(从4.5%~21.5%到3.5%~20.5%,再到1.5%~17.5%)逐渐降低;托莫尔特铁(锰)矿沉积期成矿流体以中低温(集中在160℃~300℃)、低盐度(主要集中在4%~9%和14%~20%)为特征;两棵树伟晶岩型铁矿成矿流体为中温(173℃~290℃)、低盐度(0.35%~16.05%);氢和氧同位素特征表明,火山沉积型铁矿沉积期成矿流体是海水与岩浆水的混合,矽卡岩阶段成矿流体主要为岩浆水,石英-硫化物-碳酸盐阶段成矿流体主要为大气降水,混合少量岩浆水,同时两棵树伟晶岩型铁矿成矿流体主要来源于岩浆水和大气降水的混合;碳和氧同位素表明,矽卡岩型铁矿成矿流体中碳主要来自深部岩浆,少量来自海相碳酸盐岩。  相似文献   

10.
The Qinggouzi stibnite deposit is located in Huashan Town, Jilin Province, in the northeastern margin of North China Craton(NCC). It is controlled by fault structures, hosted within structurally controlled felsic dykes, predominantly surrounded by phyllite, schist and quartzite. This study presents the results of fluid inclusions studies, intending to determine the source of the fluid responsible for ore-formation, hence exploring its metallogenesis. The aqueous biphase inclusions are identified in the stibnite-bearing quartz veins of the deposit. Moreover, aqueous biphase inclusions are further classified into(1) biphase liquid-rich inclusions(1 a) and(2) biphase gas-rich inclusions(1 b) depending upon liquid to gas ratio trapped within the fluid inclusions. Homogenization temperatures for(1 a) and(1 b) range between 114.8℃ to 422℃ and 128.3℃ to 267.5℃, respectively. 1 a and 1 b have salinities of 0.18% to 16.14% NaCl_(eqv) and 1.22% to 12.88% NaCl_(eqv), and density range from 0.43 to 1.02 g/cm~3 and 0.81 to 0.98 g/cm~3, respectively. Sulfur isotopic analysis indicates δ~(34)S_(V-CDT) from 4.4×10~(-3) to 6.5×10~(-3), with an average of 5.2×10~(-3), whereas H isotopes values on δD_(V-SMOW) standard are-100.8×10~(-3) and-107.5×10~(-3), while O isotopes data on δ~(18)O_(V-SMOW) standard range between 20.1×10~(-3) and 20.4×10~(-3). Fluid inclusions study, combining with sulfur and H-O isotopic data reveal that the ore-forming fluids originated from deep source and were subsequently contaminated by meteoric water. Hydrostatic pressure calculation shows that the minimum and maximum pressures are 11.65 and 42.33 MPa, and relevant depths of deposit are estimated to be 1.16 and 4.23 km. Finally, we inferred that Qinggouzi stibnite deposit is a medium-low temperature, low salinity hydrothermal deposit, which is formed by deep source and later contaminated by meteoric water, and is classified as epizonal deposit in terms of orogenic series.  相似文献   

11.
Haigou gold deposit is a typical orogenic gold deposit. There are a reasonable amount of fluid inclusions in the gold deposit,including three types: CO2-H2O-Na Cl inclusions,pure CO2 inclusions and Na Cl-H2 O inclusions,of which most of them are CO2-bearing inclusions. The fluid salinity is 1. 43%- 9. 08%,mainly concentrated in the range of 4. 69%- 5. 41%,the density of CO2 is 0. 69- 0. 80 g / cm3,indicating that the mineralization fluid is low-medium salinity and low density fluid. A series of studies on gold-bearing quartz vein and fluid inclusions show that there exists a positive correlation between the degree of the gold mi-neralization and the amount of CO2 in the inclusions,which means the more CO2-bearing inclusions there are,the higher the content of gold is. CO2 is mainly derived from mantle fluid,and the ore-forming fluid should be derived from mantle fluid and the crust shallow fluid. The conclusions have important denotative meaning on the metallogenic mechanism of orogenic gold deposit and the deep prospecting on metal deposit.  相似文献   

12.
洒西钨铍矿床位于滇东南老君山钨锡多金属成矿区。确定早期似层状矿体和晚期脉状矿体的流体性质、来源和演化过程, 并对其流体地球化学和同位素进行约束, 可以有效探讨洒西钨铍矿床成矿机制, 为老君山矿集区下一步找矿工作提供理论思考。洒西钨铍矿床脉状矿体的形成经历了硅酸盐阶段、氧化物-硫化物阶段和碳酸盐-萤石阶段, 白钨矿和绿柱石主要形成于前两阶段。对洒西钨铍矿床脉状矿体不同阶段石英中的流体包裹体进行了岩相学特征、显微测温、激光拉曼光谱分析等研究, 并对早期似层状矿体和晚期脉状矿体矿石中石英的氢-氧同位素组成进行了测试。结果表明: 该矿床内脉状矿体的流体包裹体主要有富液相包裹体、富气相包裹体和含子矿物多相包裹体3种类型。流体包裹体的气相成分以H2O主, 含少量还原性气体如C2H2等, 液相成分也以H2O为主。从硅酸盐阶段到碳酸盐-萤石阶段, 包裹体的均一温度和盐度(NaCleq)峰值范围分别为240~360℃、2.35%~13.81%;220~310℃、4.03%~9.86%和190~270℃、2.41%~6.88%。从硅酸盐阶段到碳酸盐-萤石阶段, 成矿流体的温度呈现降低趋势, 盐度也呈降低趋势。成矿流体总体上属中-高温度、低盐度、贫CO2、含部分还原性气体的NaCl-H2O流体体系。早期似层状矿体石英样品δDV-SMOW值变化范围小, 为-102.8‰~-99.0‰, δ18OV-SMOW值为11.7‰~13.0‰, δ18OH2O值为3.16‰~6.46‰; 晚期脉状矿体氧化物-硫化物阶段石英样品δDV-SMOW值变化范围较大, 为-99.6‰~-69.5‰, δ18OV-SMOW值为11.2‰~14.1‰, δ18OH2O值为3.08‰~6.73‰。综合表明成矿流体主要是岩浆水, 混合有少量大气降水或有机水, 流体可能发生了沸腾作用, 加之温度的降低, 导致晚期脉状矿体氧化物-硫化物阶段主要成矿物质的沉淀。洒西钨铍矿床属于中高温热液矿床。   相似文献   

13.
本文仅对广西灌阳县古怪冲锡矿床的岩石、矿石中的石英流体包裹体特征研究,探索了成岩、成矿的物理化学条件。认为成矿流体源于花岗岩浆,含锡云英岩是残余岩浆期的产物,伟晶岩与含锡石英脉具岩浆期后热液属性。根据石英包裹体的各种数据,可确定成矿物质来源,划分成岩、成矿阶段,以及矿床形成的物理化学条件。  相似文献   

14.
扬子地块东南缘是我国重要的铅锌成矿带,而其中凤凰矿田尚缺系统研究。以凤凰铅锌矿床为研究对象,运用流体包裹体地质学、同位素地球化学以及显微激光拉曼光谱等方法对成矿流体特征、流体来源及流体成分开展了系统研究。结果表明:矿床中闪锌矿和与成矿有关的脉石矿物中流体包裹体较发育;包裹体主要为气液两相,其均一温度介于111.2~177℃,盐度介于4.1%~25.2%,密度介于0.98~1.09 g/cm3,总体为低温、中高盐度、中等密度流体;石英、闪锌矿中单个包裹体成分拉曼光谱测试结果表明,气液两相包裹体中气相成分主要为CH4,液相主要为H2O,纯气相包裹体主要成分为CH4;H-O同位素分析结果表明,成矿流体主要为建造水,表明来自盆地中的建造水萃取了深部地层中的成矿物质,并与沉积物中有机物干馏作用产生的CH4等一起形成还原性成矿流体,沿同生断裂构造等通道向上运移,铅锌等成矿物质在浅部敖溪组白云岩中沉淀成矿。   相似文献   

15.
盘子涧金矿地处山东胶东地区蓬莱—栖霞金成矿带南部,是典型的石英脉型金矿,Au品位高,目前对该矿床成矿流体来源的研究尚不深入。在详细的矿相学观察及黄铁矿显微结构研究基础上,对盘子涧金矿主成矿阶段(石英-黄铁矿(绢云母)阶段和金-石英-多金属硫化物阶段)的载金黄铁矿进行了流体包裹体He-Ar同位素组成分析。结果表明:盘子涧金矿载金黄铁矿中流体包裹体的3He丰度为(3.49~8.50)×10^-14 cm^3 STP·g^-1,4He丰度为(2.46~5.06)×10^-8 cm^3 STP·g^-1,3He/4He值为0.8 Ra^1.2 Ra(Ra为大气3He/4He值,Ra=1.39×10^-6),成矿流体表现出以富集地幔为主导的壳幔混合特征;40Ar丰度为(1.02~2.65)×10^-7 cm^3 STP·g^-1,40Ar/36Ar值为896.3~1724.1,是大气饱和水40Ar/36Ar值的2~3倍,与中国东北部幔源岩样品40Ar/36Ar值相近,推测成矿流体主要来源于富集地幔,成矿流体中存在着一定量的地壳放射性成因40Ar,表明地壳流体参与了成矿作用。综上所述,推断山东胶东地区盘子涧金矿成矿流体为以富集地幔流体为主导的壳幔混合流体。  相似文献   

16.
The Wadi Sharis orogenic gold deposit in northwestern Yemen is related to the fault and shear zones vein at medium depth in the crust in the Neoproterozoic meta-sedimentary and meta-volcanosedimentary succession of greenschist to amphibolite facies metamorphism.Three distinct fluid inclusion types have been identified in the gold-bearing quartz sulphide veins of the deposit:(1) type I:vapour-liquid two-phase(VH2O-LH2O),(2) type II:three-phase CO2(VCO2-LH2O-LCO2) and(3) type III:vapour-rich(LCO2-VCO2) inclusions.Six analysis of individual fluid inclusion indicate the fluid inclusions comprise mainly of H2O and CO2.Formation P-T conditions recorded by fluid inclusions in quartz crystals correspond to 180℃-380℃ and up to 130 MPa,as indicated by high-density CO2 bubbles(up to 0.98 g/cm3) observed in some inclusions.The estimated crystallization pressures correspond to approximately 4-10 km of overburden,assuming a lithostatic load.The salinity ranges from 0 to 22 wt%.The deposit holds at 0.2-5 g/t Au and contains low-moderate salinity.  相似文献   

17.
苏旭亮 《山东国土资源》2014,30(2):20-23,28
文登市侯家地区处于牟乳成矿带东南侧,区内分布有数个小型"金牛山"式金矿床,矿体多受近EW向构造蚀变带控制,为充填在蚀变带中的多金属硫化物石英脉型金矿,属深熔浅成中低温岩浆热液型金矿床。总结金矿地质特征,依据成矿条件分析了找矿前景,指出重点工作区。  相似文献   

18.
本文用动力成矿观点对小秦岭金矿田富矿体的形成提出了新的解释,对本区的动力成矿特点作了较详细的说明。文中联系到地壳演化的不同阶段对金矿的富化过程进行了较深入的讨论,并提出了新的成矿系列。笔者以基础地质、大地构造和同位素年龄资料为依据对小秦岭金矿田含金石英脉的成因提出了与前人不同的新观点,认为它是晋宁晚期岩浆期后热液矿床。  相似文献   

19.
滇黔交界地区玄武岩铜矿流体包裹体地球化学特征   总被引:2,自引:0,他引:2  
为了探讨玄武岩铜矿成矿流体的特征,对滇黔交界地区峨眉山玄武岩铜矿3个成矿期次铜矿石中石英和方解石的气液包裹体进行了激光拉曼成分研究和均一温度、盐度测定,对古石油包裹体通过荧光显微镜进行了成分鉴定.结果表明:第1、2期次成矿流体主要为盆地卤水,其气液包裹体气液比小(一般5%~10%),w(NaCl)为8%~22%,气相为...  相似文献   

20.
In order to understand the mechanism(s) of gold precipitation in the anorthosite- hosted Sangchon gold deposits in the Hadong area, Korea, chemical speciation and reaction path calculations were accomplished by geochemical modeling.The modeling consisted of three- step procedures: reaction with anorthosite, then the simple cooling of the reacted fluid,and finally the boiling of metalliferous fluid. The principal vein minerals of the Sangchon deposits consist of quartz, sericite,kaolinite, pyrite, galena, chalcopyrite, sphalerite and acanthite. The sulfide mineralization is typically zoned from pyrite (preferentially at vein margins) to galena and sphalerite (toward vein center). Electrum is intimately associated with pyrite + chalcopyrite and sphalerite. By comparing the results of modeling with the observed mineral assemblages and paragenesis,the most appropriate evolution path of ore fluids was suggested as follow: reaction of a single fluid with anorthosite at 300℃,then the isobaric cooling of the fluid at temperatures from 2500° to 100℃3 , and then the boiling and cooling of the fluid due to the decrease of pressure and temperature. Calculations also show that all of the observed alteration minerals formed due to fluid - anorthosite interaction at early period, whereas most of sulfides and electrum were precipitated mainly due to cooling.The abundance of gold in veins depends critically on the ratio of total base metals plus iron to sulfide in the aqueous phase,because gold is transported as Au(HS)2- whose solubility is very sensitive to the sulfide activity. Our results of geochemical modeling generally fit to the observed mineral assemblages and mineral composition, indicating the usefulness of numerical simulation for elucidating the genesis of gold deposits.  相似文献   

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