滇中郝家河砂岩型铜矿床成矿作用过程的流体包裹体证据

通过对牟定郝家河砂岩型铜矿床的不同结构构造及矿化类型岩石中矿物包裹体特征的研究及对比,认为不同结构构造及矿化类型岩石的形成与不同成岩-成矿阶段流体的演化特点密切相关。流体包裹体测温数据表明其成矿作用主要经历3个成矿流体演化阶段:成岩期(均一温度:84℃~162℃)、主改造期(均一温度:145℃~227℃)及次改造期(均一温度:129℃~177℃)。3期流体的盐度变化不大,多处于4%~10%之间,而它们的气相成分主要为H2O,其次为CH4和CO2。成岩期流体演化形成了砂岩铜矿的初始矿源层及贫矿体,矿化程度高的地方甚至形成浸染状或纹层状矿石;改造-成矿期的流体则在原来基础上进一步演化形成现今受构造控制的条带状、脉状富矿体。     

东天山小热泉子矿床流体包裹体及矿床成因

小热泉子铜矿是东天山最早发现的铜矿床之一,但其成矿流体性质、演化,以及矿床成因尚不明确.通过对不同成矿期次流体包裹体开展显微测温和激光拉曼分析,结果表明小热泉子成矿可分为VMS成矿期（包含黄铁矿、黄铜矿-闪锌矿阶段）、热液叠加期（包含石英-硫化物、碳酸盐阶段）和表生期.VMS成矿期包裹体以水溶液型为主,少量含CO₂包裹体,其均一温度为234~392 ℃,盐度为3.5%~13.3% NaCleqv;热液叠加期包裹体为水溶液型,在122~296 ℃达到均一,盐度为1.4%~12.1% NaCleqv.激光拉曼分析显示包裹体成分以H₂O为主,含少量CO₂和SO₂.小热泉子铜矿早期高温-中高盐度的VMS成矿系统叠加了后期低温-中低盐度的热液系统,其成因类型应为典型的叠加型成矿系统.      

河北撒岱沟门斑岩型钼矿床流体特征对成矿过程的指示

撒岱沟门斑岩型钼矿床位于华北板块北缘东段,矿体产于印支期二长花岗岩中,矿化类型以细脉状、网脉状和浸染状辉钼矿为主.流体包裹体岩相学显示,成矿前期的无矿石英脉和成矿期含钼石英脉中流体包裹体形成较好,以气液两相为主,存在少量的单相包裹体和三相包裹体.流体包裹体显微测温研究结果显示,成矿前期包裹体的均一温度为196.2~390.0℃,盐度5.70%~17.52%（NaCl当量）;成矿期包裹体的均一温度为161.5~340.3℃,盐度在2.06%~13.29%（NaCl当量）.激光拉曼光谱测试结果显示,成矿早期以H₂O为主,存在少量CO₂和CO₃^2-;而成矿期包裹体成分中有H₂O和CO₂的两相包裹体、含CO₂的三相包裹体、SO₂和CH₄气体.流体特征变化指示成矿流体从成矿早期到晚期,温压条件不断降低,从氧化环境向还原环境转变.成矿流体经历了沸腾作用、流体不混溶作用,并伴随着大气降水混入形成了典型大陆碰撞体系下的浆控高温热液-斑岩型钼矿床.     

黑龙江省逊克县坤得气南山金矿床流体包裹体研究

坤得气南山金矿床产出于小兴安岭-张广才岭多金属成矿带北缘,矿体赋存于光华组硅化长石砂岩、细砂岩中.金矿化包括石英-黄铁矿、石英-多金属硫化物和石英-方解石3个成矿阶段.前两个阶段矿石硅化石英细脉中的石英矿物的流体包裹体,包括气液两相包裹体、富气相包裹体和含子矿物三相包裹体3种类型,并以气液两相包裹体为主.流体包裹体的均一温度变化范围在234.8~420.5℃之间,盐度（NaCl当量质量分数）变化在2.6%~33.6%之间,可分为高温低盐度、中高温中低盐度和中高温中高盐度类.流体包裹体气相成分主要为H₂O、CO₂;液相成分也以H₂O、CO₂为主,含有Na⁺、K⁺、Ca²⁺、Mg²⁺离子;子矿物主要为石盐.3类包裹体在同一矿物颗粒中同时共生发育,表明捕获流体为不均匀流体状态,显示成矿过程中存在一定程度的溶体不混溶作用.根据流体包裹体研究结果,确定矿床为浅成热液成因,而且矿床深部具有找寻斑岩型矿化的潜力.     

山东谢家沟金矿流体包裹体研究及其地质意义

山东谢家沟金矿是新发现的产于玲珑型花岗岩中的蚀变岩型金矿。对3个成矿阶段含矿流体的温度、压力和成分分析表明,矿床属于浅成中温热液矿床。含矿流体的演化是从高温向低温、从低盐度、低密度向高盐度、高密度的转变。Ⅰ成矿阶段流体包裹体均一温度为320~350 ℃,盐度为2.7%~6.6%,密度为0.498~0.886 g/cm³;Ⅱ成矿阶段包裹体均一温度为270~330 ℃,盐度为3.6%~8.4%,密度为0.571~0.959 g/cm³;Ⅲ成矿阶段包裹体均一温度为250~290 ℃,盐度为5.8%~10.6%,密度为0.724~1.158 g/cm³。流体成分以CO₂和H₂O为主,尚有CO、CH₄、H₂S、SO₂、N₂等,流体中CO2含量与矿石金品位正相关。据不同类型包裹体共生组合及流体演化特征,认为流体的不混溶性是导致大量金沉淀的主要原因。     

河南伏牛山金矿成矿流体性质及找矿意义

伏牛山东麓主要发育中低温热液型和构造蚀变岩型金矿,矿床分布受区域剪切带控制。两类金矿床各自赋存的围岩不同,且其流体包裹体中的盐度、密度、Na⁺/K⁺比值及氢、氧同位素组成显示出较大的差异,表明围岩及成矿流体性质对成矿起联合控制作用。根据包裹体同位素分析,推测成矿物质来源于变质水且有岩浆水和雨水的混入。结合单矿物电子探针测定结果,计算了围岩成岩、变质及成矿的温度、压力和沉淀条件。同时确定了富CO₂包裹体的泡腾包裹体群、液相成分的高硫富HCO₃^-、气相成分中高CO₂及CO₂/H₂O比值等特点是寻找此类金矿床的重要包裹体标志。     

云南东川铜矿床流体演化与成矿机制研究

东川铜矿床是我国重要的沉积岩容矿的层状铜矿床(SSC),具有显著的多层位成矿特征和典型的铜硫化物分带。本研究以不同层位铜矿体的流体包裹体为研究对象,通过岩相学观察、显微测温和激光拉曼成分分析,发现东川群多层位铜矿体存在浅色和深色包裹体2种类型:浅色包裹体成分以H₂O为主,含丰富的石盐子晶和少量钾盐、硬石膏子晶,代表了氧化型含矿卤水,具中低温(140~300 ℃)、中高盐度(12%~44%)的特征,属于Na ⁺、K ⁺、Ca ²⁺-Cl ^-(SO₄ ^2-)型盆地卤水,主要来源于海相蒸发岩的溶解和层间建造水;深色的含有机质包裹体代表了还原型流体,来源于黑山组碳质板岩和落雪组中的藻类生物分解。东川铜矿床以落雪组的含叠层石砂质白云岩作为主要沉淀系统,黑山组碳质板岩为隔挡层,形成一个流体封闭的物理化学圈闭,氧化含矿卤水通过供给系统运移到具还原性质的沉淀系统中,与还原型富硫流体和含有机质的地层发生混合反应,形成多层位的层状铜矿体和层控脉状铜矿体。     

青海东昆仑阿斯哈金矿Ⅰ号脉成矿流体地球化学特征和矿床成因

阿斯哈金矿位于东昆中隆起带东段,是东昆仑重要的金、铁多金属成矿带。金矿的容矿围岩为印支早期闪长岩和黑云母花岗岩,NNE向和NW向断裂为主要的容矿构造,Ⅰ号脉为该金矿主要的矿脉之一,云煌岩与金矿脉空间关系密切。流体包裹体主要有富CO₂三相和气液两相2种类型。流体盐度（w(NaCl)）为1.83%~8.13%,流体密度为0.69~0.87 g/cm³,成矿温度为155.3~425.6 ℃。成矿Ⅰ阶段流体为低盐度、富CO₂的高温流体;成矿Ⅱ阶段富CO₂型和气液两相流体包裹体共存,发生了以CO₂逸失为特征的不混溶或沸腾,致使残余流体盐度升高;成矿Ⅲ阶段为气液两相包裹体。激光拉曼光谱分析表明,流体气相成分主要有CO₂、CH4、N₂。结合氢、氧和硫同位素组成分析认为,成矿流体主要为幔源流体,晚期有大气水的加入。通过等容线图解法估算成矿压力为98~132 MPa,估算成矿深度为8.16~9.58 km。通过与典型造山型金矿特征对比,阿斯哈金矿为中成造山型金矿,矿床形成于早印支期陆内造山由挤压向伸展转换时期。     

内蒙古额尔古纳地区七一牧场铅锌矿床成矿流体特征及成因探讨

七一牧场矿床是内蒙古额尔古纳成矿带内新发现的一个铅锌矿床,具有大中型矿床的成矿潜力.为确定该矿床的成矿流体特征及成因类型,对主成矿阶段的石英开展了流体包裹体岩相学观察、显微测温和激光拉曼光谱分析.结果表明,石英中主要发育富液相、富气相、CO₂三相和少量含子矿物三相包裹体;包裹体的均一温度为132~342℃,大致集中在130~200℃和240~320℃;两相包裹体的盐度范围在0.5%~9.9%,含CO₂三相包裹体的盐度为3.0%~11.9%,属低盐度.根据子矿物熔化温度得出含子矿物三相包裹体的盐度为42.4%和44.2%.激光拉曼光谱分析显示,包裹体中气相成分主要为H₂O和CO₂.认为流体的沸腾作用是矿质沉淀的重要机制,该矿床属赋存于中生代火山岩中与浅成-超浅成岩浆作用有关的中低温热液脉型矿床.     

海南高通岭石英脉型钼矿床成矿流体来源与成矿机制研究

高通岭矿床是海南岛典型的石英脉型钼矿床。基于流体包裹体以及H、O、S、Pb同位素研究,本文对高通岭石英脉型钼矿床成矿流体性质、成矿物质来源及成矿机制进行了讨论。结果表明,(1)流体包裹体以富液两相水溶液(A-L型)为主,次为富液两相含CO₂水溶液(AC-L型)和富气两相含CO₂溶液(AC-V型); A-L及AC-L型包裹体均一成液相, AC-V型包裹体均一成气相。均一成液相和均一成气相的包裹体共生指示流体不混溶或沸腾。拉曼结果显示流体成分以H₂O为主,其次是CO₂,含微量N₂、CH₄和H₂等气体;成矿期流体包裹体均一温度为180～280℃,盐度为4.0%～8.2%NaCleqv;(2)H-O同位素组成显示成矿流体具有岩浆水与大气降水混合特点; δ³⁴S值域为-0.9‰～5.5‰,均值2.8‰,属于深源硫;(3)Pb同位素组成及特征参数暗示其具有岩浆作用带来的地幔Pb与上地壳Pb混合成因。据此,高通岭钼矿床成矿流体...     

A Study of Ore-forming Fluids in the Shimensi Tungsten Deposit, Dahutang Tungsten Polymetallic Ore Field, Jiangxi Province, China

The Dahutang tungsten polymetallic ore field is located north of the Nanling W-Sn polymetallic metallogenic belt and south of the Middle—Lower Yangtze River Valley Cu-Mo-Au-Fe porphyry-skarn belt.It is a newly discovered ore field,and probably represents the largest tungsten mineralization district in the world.The Shimensi deposit is one of the mineral deposits in the Dahutang ore field,and is associated with Yanshanian granites intruding into a Neoproterozoic granodiorite batholith.On the basis of geologic studies,this paper presents new petrographic,microthermometric,laser Raman spectroscopic and hydrogen and oxygen isotopic studies of fluid inclusions from the Shimensi deposit.The results show that there are three types of fluid inclusions in quartz from various mineralization stages:liquid-rich two-phase fluid inclusions,vapor-rich two-phase fluid inclusions,and three-phase fluid inclusions containing a solid crystal,with the vast majority being liquid-rich two-phase fluid inclusions.In addition,melt and melt-fluid inclusions were also found in quartz from pegmatoid bodies in the margin of the Yanshanian intrusion.The homogenization temperatures of liquid-rich two-phase fluid inclusions in quartz range from 162 to 363℃ and salinities are 0.5wt%-9.5wt%NaCI equivalent.From the early to late mineralization stages,with the decreasing of the homogenization temperature,the salinity also shows a decreasing trend.The ore-forming fluids can be approximated by a NaCl-H_2O fluid system,with small amounts of volatile components including CO_2,CH_4 and N_2,as suggested by Laser Raman spectroscopic analyses.The hydrogen and oxygen isotope data show that δ5D_(V-smow) values of bulk fluid inclusions in quartz from various mineralization stages vary from-63.8‰ to-108.4‰,and the δ~(18)O_(H2O) values calculated from the δ~(18)O_(V-)smow values of quartz vary from-2.28‰ to 7.21‰.These H-O isotopic data are interpreted to indicate that the ore-forming fluids are mainly composed of magmatic water in the early stage,and meteoric water was added and participated in mineralization in the late stage.Integrating the geological characteristics and analytical data,we propose that the ore-forming fluids of the Shimensi deposit were mainly derived from Yanshanian granitic magma,the evolution of which resulted in highly differentiated melt,as recorded by melt and melt-fluid inclusions in pegmatoid quartz,and high concentrations of metals in the fluids.Cooling of the ore-forming fluids and mixing with meteoric water may be the key factors that led to mineralization in the Dahutang tungsten polymetallic ore field.     

Geology,Fluid Inclusions,and Isotopic Geochemistry of the Jinman Sediment‐Hosted Copper Deposit in the Lanping Basin,China

The Jinman Cu polymetallic deposit is located within Middle Jurassic sandstone and slate units in the Lanping Basin of southwestern China. The Cu mineralization occurs mainly as sulfide‐bearing quartz–carbonate veins in faults and fractures, controlled by a Cenozoic thrust–nappe system. A detailed study of fluid inclusions from the Jinman deposit distinguishes three types of fluid inclusions in syn‐ore quartz and post‐ore calcite: aqueous water (type A), CO₂–H₂O (type B), and CO₂‐dominated (type C) fluid inclusions. The homogenization temperatures of CO₂–H₂O inclusions vary from 208°C to 329°C, with corresponding salinities from 0.6 to 4.6 wt.% NaCl equivalent. The homogenization temperatures of the aqueous fluid inclusions mainly range from 164°C to 249°C, with salinities from 7.2 to 20.2 wt.% NaCl equivalent. These characteristics of fluid inclusions are significantly different from those of basinal mineralization systems, but similar to those of orogenic or magmatic mineralization systems. The H and O isotope compositions suggest that the ore‐forming fluid is predominantly derived from magmatic water, with the participation of basinal brine. The δ³⁴S values are widely variable between ?9.7 ‰ and 9.7 ‰, with a mode distribution around zero, which may be interpreted by the variation in physico‐chemical conditions or by compositional variation of the sources. The mixing of a deeply sourced CO₂‐rich fluid with basinal brine was the key mechanism responsible for the mineralization of the Jinman deposit.     

论滇中砂岩铜矿浅、紫交互带赋矿及其金属硫化物分带之成因与成矿作用演化

康滇古大陆裂谷的发生和演化造就了楚雄盆地,沉积出煤、铜、盐旋回与含矿建造和矿床组合.铜矿的生成(特别是改造富集)与煤(有机质)、盐(热卤水)密切相关.大姚—牟定式砂岩铜矿以其规模最大而具代表性.它的成矿作用的演化是从风化沉积作用到成岩作用、后生作用再到改造作用.作用的结果是分别产生含铜有机质沉积体、成岩矿层、后生矿层和改造富矿体.层状矿体赋存于砂岩浅紫交互带是氧化性流体与还原性流体相汇于斯而发生氧化—还原反应沉积成岩的结果.其金属硫化物的生成顺序与分带是遵循S、O、Fe、Cu热液体系中矿物共生组合规律的,随介质条件、四元素浓度的差异而变化.     

Metallogenetic Mechanism and Timing of Late Superimposing Fluid Mineralization in the Dongguashan Diplogenetic Stratified Copper Deposit,Anhui Province

1 Introduction The region of the middle-lower reach of the Yangtze River is an important mineralized belt of Fe, Cu, Au, S and other elements, with a series of sedimentary-hydrothermal diplogenetic mineral deposits (Xu and Zhu, 1978; Liu et al., 1984; Gu and Xu, 1986; Gu et al., 1993, 2000; Zhai et al., 1992). Some geologists thought that the Carboniferous massive sulfide exhalative sediment was the basis of the late diplogenetic mineralization (Gu and Xu, 1986; Gu et al., 1993, 2000); o…     

Fluid Inclusions and C?H?O?S?Pb Isotopes: Implications for the Genesis of the Zhuanshanzi Gold Deposit on the Northern Margin of the North China Craton

The Zhuanshanzi gold deposit lies in the eastern section of the Xingmeng orogenic belt and the northern section of the Chifeng‐Chaoyang gold belt. The gold veins are strictly controlled by a NW‐oriented shear fault zone. Quartz veins and altered tectonic rock‐type gold veins are the main vein types. The deposits can be divided into four mineralization stages, and the second and third metallogenic stages are the main metallogenic stages. In this paper, based on the detailed field geological surveys, an analysis of the orebody and ore characteristics, microtemperature measurement of fluid inclusions, the Laser Raman spectrum of the inclusions, determination of C? H? O? S? Pb isotopic geochemical characteristics, and so on were carried out to explore the origin of the ore‐forming fluids, ore‐forming materials, and the genesis of the deposits. The results show that the fluid inclusions can be divided into four types: type I – gas–liquid two‐phase inclusions; type II – gas‐rich inclusions; type III– liquid inclusions; and type IV – CO₂‐containing three‐phase inclusions. However, they are dominated by type Ib – gas liquid inclusions and type IV – three‐phase inclusions containing CO₂. The gas compositions are mainly H₂O and CO₂, indicating that the metallogenic system is a CO₂? H₂O? NaCl system. The homogenization temperature of the ore‐forming fluid evolved from a middle temperature to a low temperature, and the temperature of the fluid was further reduced due to meteoric water mixing during the late stage, as well as a lack of CO₂ components, and eventually evolved into a simple NaCl? H₂O hydrothermal system. C? H? O? S? Pb isotope research proved that the ore‐forming fluids are mainly magmatic water during the early stage, with abundant meteoric water mixed in during the late stage. Ore‐forming materials originated mostly from hypomagma and were possibly influenced by the surrounding rocks, suggesting that the ore‐forming materials were mainly magmatic hydrothermal deposits, with a small amount of crustal component. The fluid immiscibility and the CO₂ and CH₄ gases in the fluids played an active and important role in the precipitation and enrichment of Au during different metallogenic stages. The deposit is considered a magmatic hydrothermal deposit of middle–low temperature.     

Fluid Inclusions,Stable Isotopes,and Geochronology of the Haobugao Lead‐Zinc Deposit,Inner Mongolia,China

The Haobugao deposit, located in the southern segment of the Great Xing'an Range, is a famous skarn‐related Pb‐Zn‐(Cu)‐(Fe) deposit in northern China. The results of our fluid inclusion research indicate that garnets of the early stage (I skarn stage) contain three types of fluid inclusions (consistent with the Mesozoic granites): vapor‐rich inclusions (type LV, with V_H2O/(V_H2O + L_H2O) < 50 vol %, and the majority are 5–25 vol %), liquid‐rich two‐phase aqueous inclusions (type VL, with V_H2O/(V_H2O + L_H2O) > 50 vol %, the majority are 60–80 vol %), and halite‐bearing multiphase inclusions (type SL). These different types of fluid inclusions are totally homogenized at similar temperatures (around 320–420°C), indicating that the ore‐forming fluids of the early mineralization stage may belong to a boiling fluid system. The hydrothermal fluids of the middle mineralization stage (II, magnetite‐quartz) are characterized by liquid‐rich two‐phase aqueous inclusions (type VL, homogenization temperatures of 309–439°C and salinities of 9.5–14.9 wt % NaCl eqv.) that coexist with vapor‐rich inclusions (type LV, homogenization temperatures of 284–365°C and salinities of 5.2–10.4 wt % NaCl eqv.). Minerals of the late mineralization stage (III sulfide‐quartz stage and IV sulfide‐calcite stage) only contain liquid‐rich aqueous inclusions (type VL). These inclusions are totally homogenized at temperatures of 145–240°C, and the calculated salinities range from 2.0 to 12.6 wt % NaCl eqv. Therefore, the ore‐forming fluids of the late stage are NaCl‐H₂O‐type hydrothermal solutions of low to medium temperature and low salinity. The δD values and calculated δ¹⁸O_SMOW values of ore‐forming fluids of the deposit are in the range of ?4.8 to 2.65‰ and ?127.3‰ to ?144.1‰, respectively, indicating that ore‐forming fluids of the Haobugao deposit originated from the mixing of magmatic fluid and meteoric water. The S‐Pb isotopic compositions of sulfides indicate that the ore‐forming materials are mainly derived from underlying magma. Zircon grains from the mineralization‐related granite in the mining area yield a weighted ²⁰⁶Pb/²³⁸U mean age of 144.8 ±0.8 Ma, which is consistent with a molybdenite Re‐Os model age (140.3 ±3.4 Ma). Therefore, the Haobugao deposit formed in the Early Cretaceous, and it is the product of a magmatic hydrothermal system.     

兰坪白秧坪铜银多金属矿床流体地球化学特征及成矿机制探讨

白秧坪铜银多金属矿床主要产于白垩系下统景星组石英砂岩、粉砂岩中 ,矿体受一组北东向的压扭性断层控制而呈似层状、脉状产于断裂带中。包裹体分析表明成矿流体为低温 (平均124～141℃ )、低矿化度的盆地卤水 ,流体的H、O同位素组成位于大气降水线附近 ,反映了水 /岩作用程度较低、水 /岩反应时限短 ,流体流动与循环速度较快。计算机模拟结果表明在景星组沉积之后的13～16Ma期间断裂作用所产生的断裂渗透性达到最大 ,此期间流体演化的温度也达到125～140℃。断裂作用所产生的高断裂渗透性对周围地层中的流体产生泵吸作用并形成流体流动的断裂引水渠 ,从而导致大量流体在断裂带中快速流动、循环和汇聚成矿     

Geologic, Fluid Inclusion and Stable Isotope Constraints on Mechanisms of Ore Deposition at the Datuanshan Copper Deposit, Middle–Lower Yangtze Valley, Eastern China

The Datuanshan deposit is one of the largest and most representative stratabound copper deposits in the Tongling area,the largest ore district in the Middle-Lower Yangtze River metallogenic belt.The location of the orebodies is controlled by the interlayer-slipping faults between the Triassic and Permian strata,and all the orebodies are distributed in stratiform shape around the Mesozoic quartz monzodiorite dikes.Based on field evidence and petrographic observations,four mineralization stages in the Datuanshan deposit have been identified:the skarn,early quartz-sulfide,late quartzsulfide and carbonate stages.Chalcopytite is the main copper mineral and mainly formed at the late quartz-sulfide stage.Fluid inclusions at different stages were studied for petrography,microthermometry,laser Raman spectrometry and stable isotopes.Four types of fluid inclusions,including three-phase fluid inclusions(type 1),liquid-rich fluid inclusions(type 2),vapour-rich fluid inclusions(type 3) and pure vapour fluid inclusions(type 4),were observed.The minerals from the skarn,early and late quartz-sulfide stages contain all fluid inclusion types,but only type 2 fluid inclusions were observed at the carbonate stage.Petrographic observations suggest that most of the inclusions studied in this paper are likely primary.The coexistence of different types of fluid inclusions with contrasting homogenization characteristics(to the liquid and vapour phase,respectively) and similar homogenization temperatures(the modes are 440-480℃,380-400℃ and 280-320℃ for the skarn,early and late quartz-sulfide stages,respectively) in the first three stages,strongly suggests that three episodes of fluid boiling occurred during these stages,which is supported by the hydrogen isotope data.Laser Raman spectra identified CH_4 at the skarn and early quartz-sulfide stages.Combined with other geological features,the early ore-forming fluids were inferred to be under a relatively reduced environment.The CO_2 component has been identified at the late quartz-sulfide and carbonate stages,indicating that the late ore-forming fluids were under a relatively oxidized environment,probably as a result of inflow of and mixing with meteoric water.In addition,microthermometric results of fluid inclusions and H-O isotope data mdicate that the ore forming fluids were dominated by magmatic water in the early stages(skarn and early quartz-sulfide stages) and mixed with meteoric water in the late stages(late quartz-sulfide and carbonate stages).The evidence listed above suggests that the chalcopyrite deposition in the Datuanshan deposit probably resulted from the combination of multiepisode fluid boiling and mixing of magmatic and meteoric water.     

川西北马脑壳金矿床成矿流体地球化学特征与性质

马脑壳金矿床是20世纪80年代末期在川西北地区发现的一大型微细浸染型矿床，它赋存于中三叠统扎尕山组地层之中，矿体产出受北西向次级断裂构造的控制。矿床的形成经历了成矿前金初步富集、热液成矿作用－原生矿石形成及麦生氧化－金次生再富集第三期主要成矿作用过程。热液金成矿作用可进一步划分为（1）黄铁矿－毒砂－石英；（Ⅱ）石英－（白钨矿）－辉锑矿；（Ⅲ）石英－雄（雌）黄及（Ⅳ）石英－方解石等4个矿化阶段，其中Ⅰ、Ⅱ阶段为金的主要沉淀富成矿阶段。系统的流体包裹体研究表明，成矿前（Ⅰ′）及热液成矿Ⅰ－Ⅳ阶段石英中共发育液相、纯液相、含CO2三相、富CO2相及含有机质等5种类型的原生流体包裹体。测温结果显示，Ⅰ′及Ⅰ-Ⅳ类石英中液相及含CO2三相包裹体均一温度为120－300℃，热液盐度为0．5％－11．0％；包裹体成分分析结果表明，热液阳离子以Na^ 、K^ 及Ca^2 为主，阴离子主要为HCO3^-及CI^-，气相组分除H2O外，尚含一定量的CO2及CH4等；热液pH值为6．7－72，Eh值为－0．85～0.69eV；成矿热液总体属中低温、低盐度、近中性和弱还原性的含有机质Na^ -K^ -Ca^2 -HCO3^--CI^-体系类型。H、O同位素研究结果表明，成矿前热液主要来源于变质水和地层建造水，成矿期以来大气降水不断 混入并逐步占据优势。主成矿阶段成矿热液发生过明显的注体混合相分离作用，对金的沉淀富集成矿起了重要作用。     

山东莱西山后金矿床流体包裹体特征

根据山后金矿床的矿物组合和矿物生成顺序,将成矿阶段划分为4个阶段:黄铁矿-石英(钾化)阶段、石英—黄铁矿(绢英岩化)阶段、金-石英-多金属硫化物阶段和石英-碳酸盐阶段。对区内主成矿阶段的石英中流体包裹体进行岩相学、显微测温及氢氧同位素进行分析。结果表明:矿石中的包裹体主要有含CO2三相包裹体、气液两相包裹体和CO2包裹体三种类型,矿石中的包裹体普遍富含CO2。成矿过程中,流体经历了CO2-H2O—Na Cl体系的不混溶作用。成矿流体具有低盐度(4.0~9.0 wt%Na Cl.eqv)和低密度(0.70~0.89 g/cm3)的特点。主成矿温度为260℃~300℃,成矿压力为83~100 MPa,对应成矿深度为7.45~8.25 km。流体包裹体氢氧同位素分析结果介于地幔初生水和岩浆水之间,部分向大气降水线方向漂移,表明山后金矿成矿流体以幔源流体为主,并有大气降水和其他流体的加入,初步确定山后金矿床是受断裂构造控制的中温热液脉型金矿床。