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1.
小西弓金矿床是北山造山带南带重要的中型金矿床,矿体产出受韧性剪切带控制。热液成矿过程由早到晚分为石英-黄铁矿阶段、石英-多金属硫化物阶段和石英-碳酸岩阶段。石英-黄铁矿阶段石英中发育富液二相、富气二相和含CO2三相流体包裹体,均一温度范围为228℃~438℃,盐度为4.03%~17.50%NaCleqv,属中高温、中低盐度流体。石英-多金属硫化物阶段石英中发育富液二相、富气二相、含CO2三相和纯液相流体包裹体,均一温度范围为182℃~376℃,盐度为3.23%~12.21%NaCleqv。流体演化过程中发生了流体沸腾和混合作用,这可能是导致金沉淀富集的主要机制。流体沸腾温度区间约为268℃~347℃。成矿早阶段石英中流体包裹体的δ18 O和δD值分别为8.0‰~8.3‰和-84‰~-107‰。结合矿床地质特征和氢氧同位素研究认为,初始成矿流体来自变质热液,晚阶段有大气降水加入。  相似文献   

2.
商旭金矿床处于班公湖-怒江缝合带中段南侧,位于藏北双湖县境内,是班公湖-怒江缝合带已发现的可能是造山型的金矿床。矿体赋存于中-下侏罗统木嘎岗日群浅变质复理石中,受北西西向断裂构造控制,金矿化与石英脉密切相关。含矿石英脉中见较多黄铁矿、黄铜矿、方铅矿、闪锌矿等硫化物,自然金沿石英裂隙分布,少量分布在黄铁矿裂隙中。岩相学特征和激光拉曼测定结果显示,商旭金矿床中存在两类流体包裹体:1富液相包裹体(L型);2含CO2包裹体(C型),此类包裹体主要为CO2三相包裹体,见CO2两相包裹体。显微测温结果表明:1L型包裹体的均一温度为89.6~409.8℃,盐度ω(NaCleq)为0.35%~9.34%,流体密度为0.55~0.98g/cm3;2C型包裹体的均一温度为264.3~395.2℃,盐度ω(NaCleq)为4.62%~9.74%,流体密度为0.66~0.81g/cm3。商旭金矿床成矿流体具有富CO2、中低温度、低盐度、低密度的特征,与典型造山型金矿成矿流体特征相似。同时,商旭金矿床成矿流体的氢氧同位素组成分别为δD=-108‰~-89‰、δ18 O=-0.8‰~5.8‰,表明成矿流体主要来自变质水与建造水的混合。综合流体包裹体和氢氧同位素证据,进一步论证商旭金矿床为造山型金矿。  相似文献   

3.
合仁坪金矿床位于湘西柳林汊金矿带,是典型的钠长石-石英脉型金矿床,本文对其进行了较系统的成矿流体地球化学研究。结果表明,与成矿有关的石英和方解石中的流体包裹体主要为气液两相包裹体。石英中包裹体的均一温度范围为111~375℃,盐度为0.18%~7.86%的NaCl;方解石中包裹体的均一温度范围为196~271℃,盐度为4.18%~6.74%的NaCl;成矿溶液的密度为0.633~0.997g/cm~3,表明该矿床的成矿流体均属于中低温、低盐度和低密度的流体;成矿压力为4~209MPa,成矿深度约为1.2~6.8km,该矿床是在中低压力、中浅成条件下形成的。激光拉曼探针分析表明,包裹体中的气相成分有CO_2、CO、CH_4和N_2,液相成分为H_2O和CO_3~(2-),指示含有机质的沉积物变质脱水可能是成矿流体来源的方式。对石英和钠长石氢氧同位素研究表明,该矿成矿流体的δ~(18)O_(H_2O)值为7.1‰~10.8‰,δD_(H_2O)值介于-69‰~-55‰,合仁坪金矿的成矿流体主要来源于变质水。  相似文献   

4.
黑龙江省马连金矿床流体包裹体特征及其地质意义   总被引:4,自引:1,他引:3       下载免费PDF全文
为确定马连金矿成矿流体性质,笔者对成矿期石英开展详细的流体包裹体和氢氧同位素研究,包裹体岩相学和显微测温结果表明:石英中主要发育气相包裹体、液相包裹体和纯液相包裹体;包裹体均一温度为148~255℃(峰值为180~210℃),盐度为1.7%~7.5%Na Cleqv(峰值2%~4%Na Cleqv),属于低温、低盐度金矿床。激光拉曼和群体包裹体成分分析显示:成矿流体气相成分以H2O为主,CO2、CH4次之,液体主要成分为Ca2+、Na+、SO42-和F-,其次为K+、Mg2+、NO3-和Cl-,成矿流体属于Na Cl-H2O±CO2±CH4体系。包裹体氢氧同位素研究表明:成矿流体δDV-SMOW值介于-92.3‰~-113.4‰,δ18OH2O值介于2.5‰~3.5‰,具有岩浆水和大气降水混合的特征,结合成矿流体特征,认为流体不混溶或沸腾作用导致相分离是马连金矿沉淀主要原因。  相似文献   

5.
泥堡金矿床是黔西南台地相区以断控型矿体为主、层状型矿体为辅的复合型金矿床。断控型矿体主要发育于低角度的逆冲断层中,层状型矿体主要发育于断控型矿体之上穹窿构造核部的上二叠统龙潭组和中二叠统大厂层中。根据脉体的穿插关系和矿物共生组合,将成矿过程从早到晚划分为石英-黄铁矿阶段、石英-黄铁矿-毒砂阶段和方解石-石英-多金属硫化物±萤石阶段。泥堡金矿床两类矿体中流体包裹体类型相同,包括水溶液包裹体、CO_2-H_2O包裹体和CO_2包裹体。层状型矿体早阶段石英中流体包裹体均一温度范围为194~305℃,盐度范围为0.70%~7.81%NaC leqv,石英的δ~(18)O_(V-SMOW)为22.7~23.6‰,计算得到的δ~(18)OH 13.5‰,~-62‰;2O为12.6‰~石英中流体包裹体水的δD_(H_2O)为-84‰中阶段石英中流体包裹体均一温度范围为125~278℃,盐度范围为0.53%~6.46%NaC leqv,石英的δ~(18)O_(V-SMOW)为16.6‰~23.5‰,计算得到的δ~(18)O_(H_2O)为4.4‰~11.3‰,石英中流体包裹体水的δDH~-65‰;3~2O为-80‰晚阶段方解石中流体包裹体均一温度范围为13197℃,盐度范围为0.53%~7.45%NaC leqv,萤石中流体包裹体均一温度范围为102~264℃,盐度范围为0.18%~4.49%NaC leqv,方解石的δ~(18)O_(V-SMOW)为20.6‰~22.7‰,计算得到的δ~(18)OH 3‰~10.4‰,2O为8.方解石中流体包裹体水的δD_(H_2O)为-56‰~-47‰,δ13CV-PDB为-6.6‰~-1.6‰。断控型矿体中阶段石英中流体包裹体均一温度范围为126~296℃,盐度范围为0.35%~8.29%NaC leqv,石英的δ~(18)O_(V-SMOW)为21.9‰~23.7‰,计算得到的δ~(18)OH9.8‰~11.6‰,2O为石英中流体包裹体水的δDHNaC leqv,2O为-85‰;晚阶段方解石中流体包裹体均一温度范围为118~236℃,盐度范围为0.53%~7.02%方解石的δ~(18)O_(V-SMOW)为19.8‰~21.5‰,计算得到的δ~(18)OH~10.4‰,2O为8.7‰方解石中流体包裹体水的δDH‰~-55‰,2O为-67δ13CV-PDB为-7.0‰~-4.7‰。流体包裹体和稳定同位素研究结果表明,两类矿体成矿流体性质和来源一致,且具有相似的演化过程。泥堡金矿床的成矿流体来源于大气降水和海水的混合,并且从早阶段到晚阶段,海水所占的比例逐渐增大,碳主要来自海相碳酸盐岩的溶解。  相似文献   

6.
哈图金矿床位于新疆北部准噶尔盆地西缘哈图断裂和安齐断裂夹持的狭长地带中。矿床受安齐断裂及其周围伴生的次一级断裂的控制,主要产出石英脉型和蚀变岩型2种金矿体。根据矿物共生关系和脉体穿插关系,将哈图金矿床从早到晚划分为3个成矿阶段。石英脉流体包裹体研究显示,矿体存在3种类型的流体包裹体,分别为Ⅰ型:富液相L+V两相包裹体;Ⅱ型:富气相L+V两相包裹体;Ⅲ型:CO2-H2O型三相包裹体。早阶段发育Ⅰ型、Ⅱ型和Ⅲ型包裹体,均一温度293~379℃,流体盐度为1.0%~5.7%。中(主)阶段发育Ⅰ型、Ⅱ型和Ⅲ型包裹体,均一温度213~291℃,流体盐度为0.5%~5.9%。晚阶段只发育Ⅰ型包裹体,均一温度148~216℃,流体盐度为1.4%~4.0%。经过压力和深度计算,成矿压力为49~97 MPa,对应深度在4.8~9.4 km。根据哈图金矿石英的δ18OV-SMOW值为20.4‰~21‰,计算得到平衡水的δ18OH2O值在8.6‰~14.7‰,同时测得石英包裹体水的δ18DH2O为-77.2‰~-64.5‰。和前人研究结果对比,认为哈图金矿床为造山型中-低温热液金矿床,成矿流体是以大气降水为主体受岩浆和变质影响的低盐度CO2-H2O体系。  相似文献   

7.
辽宁小佟家堡子金矿床位于华北克拉通北缘。矿区出露地层为元古宇辽河群大石桥组大理岩和盖县组片岩,断裂构造控制着矿体的产出。矿石类型包括石英脉型和蚀变岩型。围岩蚀变类型有硅化、绢云母化和碳酸盐化。成矿过程划分为早、中、晚3个阶段,依次为石英±黄铁矿阶段、石英-多金属硫化物阶段和石英-碳酸盐阶段,金主要沉淀于石英-多金属硫化物阶段。流体包裹体研究表明,小佟家堡子矿床发育富液两相包裹体、富气两相包裹体、含CO_2包裹体和纯CO_2包裹体。成矿早阶段石英中仅见富液两相包裹体,包裹体均一温度介于311~408℃之间,盐度介于5.9%~14.3%NaCl eqv之间;成矿中阶段石英中发育富液两相包裹体、富气两相包裹体、含CO_2包裹体和纯CO_2包裹体,包裹体均一温度介于268~376℃之间,盐度介于4.1%~13.0%NaCl eqv之间;成矿晚阶段石英中仅见富液两相包裹体,均一温度介于201~254℃之间,盐度介于1.6%~7.6%NaCl eqv之间。成矿流体具中温、低盐度、富CO_2的特征,属于H_2O-NaCl±CO_2体系。流体不混溶作用是金沉淀的主要机制。成矿流体的δ~(18)OW值为0.3‰~2.3‰,δD_W值为-99.8‰~-96.2‰,表明成矿流体以岩浆水为主,混合部分变质水和大气降水。金属硫化物的δ~(34)S值介于+4.6‰~+12.9‰。金属硫化物的铅同位素比值变化较小,~(206)Pb/~(204)Pb=17.671~18.361,~(207)Pb/~(204)Pb=15.569~15.659,~(208)Pb/~(204)Pb=37.695~37.937。S-Pb同位素组成表明成矿物质主要来自辽河群变质岩和晚三叠世岩浆岩。黄铁矿中流体包裹体3He/4He值为0.27~0.53 Ra,地幔流体参与成矿作用的比例为2.9%~5.8%,地壳流体占主导地位。  相似文献   

8.
云南省富宁县者桑金矿床成矿流体特征   总被引:1,自引:0,他引:1  
通过云南者桑金矿床中流体包裹体岩相学、显微测温、稀土元素、氢氧同位素的分析,探讨了成矿流体特征。研究表明:存在液体包裹体、纯液体包裹体、纯气体包裹体和含液体CO2包裹体4种流体包裹体类型;液体包裹体均一温度为83.4~248.2℃,盐度为0.18%~6.45%,密度为0.85~1.0 g/cm3,成矿压力为10.9~59.4 MPa,成矿深度为0.2~2.2 km;各成矿阶段石英及方解石稀土元素特征表明,其成矿物理化学条件为还原环境。δ18OH2O值为-6.1‰~4.9‰;δDV-SMOW值为-40.3‰~-74.8‰,表明成矿流体来源为大气降水,岩矿石有机碳含量达到0.12%~0.45%,金品位与有机质含量呈正相关,黄铁矿及毒砂δ34SV-CDT值为9.2‰~10.2‰,表明者桑金矿床成矿热液中硫化物沉淀所需硫源为围岩中有机质与硫酸盐反应提供的还原硫。成矿热液在下渗过程中混合建造水,受到岩浆烘烤作用及地温梯度影响后再向上循环,金矿化发生在成矿流体的热循环与赋矿围岩的相互作用过程中,并在构造有利部位沉淀富集。  相似文献   

9.
江苏观山铜铅金矿床成矿流体地球化学和成因   总被引:3,自引:1,他引:2  
观山铜铅金矿矿石中含有4种类型的流体包裹体:(Ⅰ)纯液相水溶液包裹体;(Ⅱ)富液相气液两相水溶液包裹体;(Ⅲ)富气相气液两相水溶液包裹体;(Ⅳ)纯气相包裹体。它们的气相分数变化较大,显示成矿过程中可能发生过沸腾作用。流体包裹体的显微测温结果显示,成矿流体的冰点温度为-0.3℃~-4.7℃,流体盐度w(NaCleq)变化范围为0.48%~7.39%,均一温度为133~304℃,对应流体密度为0.70~0.98g/cm3。同位素测定显示成矿流体的氢氧同位素组成分别为δD水=-81.0‰~-90.0‰,δ18O水=0.1‰~2.3‰,说明成矿流体主要为大气降水,但在矿体深部可能有少量岩浆水的加入。热液方解石碳同位素δ13C方解石=-1.2‰~2.9‰,显示其中的C主要来源于流体对流循环过程中对基底岩石中碳酸盐地层的溶解。综合成矿地质特征、成矿流体的证据与围岩蚀变类型,初步推断观山铜铅金矿为高硫型浅成低温热液金属矿床,沸腾作用可能是引起矿质发生沉淀富集成矿的重要因素之一。  相似文献   

10.
胶东半岛大磨曲家金矿床成矿流体物理化学条件演化   总被引:2,自引:1,他引:1  
胶东大磨曲家金矿床流体包裹体包括水溶液包裹体、富CO2包裹体和高盐卤水包裹体3种类型,前两者发育较多,高盐卤水包裹体发育极少。流体包裹体显微测温及盐度、密度、压力估算显示,水溶液包裹体均一温度为98~376℃,据冰点温度估算,盐度为0.53%~8.28%,水溶液包裹体均一压力低于50×105Pa;富CO2包裹体完全均一温度为255~348℃,盐度为2.42%~11.43%,均一压力为1 000×105~2 500×105Pa;富CO2包裹体中CO2均一温度为23.0~32.4℃,指示该类包裹体可能含有数量不等的CH4或H2S。静水压力体制下,根据纯CO2包裹体均一压力估算成矿深度约为1 km。在270℃左右,均一压力从富CO2包裹体到水溶液包裹体急剧降低,指示成矿流体在270℃左右可能发生过一次减压沸腾过程,成矿流体盐度和密度在270℃左右也有显著的变化。因此,沸腾作用及其引起的成矿流体物理化学条件的急剧变化可能是导致大磨曲家金矿床成矿物质沉淀的重要机制。  相似文献   

11.
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others.  相似文献   

12.
最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提  相似文献   

13.
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.  相似文献   

14.
《Applied Geochemistry》2001,16(2):137-159
Five hundred and ninety-eight samples of terrestrial moss (Hylocomium splendens and Pleurozium schreberi) collected from a 188,000 km2 area of the central Barents region (NE Norway, N Finland, NW Russia) were analysed by ICP-AES and ICP-MS. Analytical results for Al, B, Ba, Ca, K, La, Mg, Mn, Na, P, Rb, Si, Sr, Th, U and Y concentrations are reported here. Graphical methods of data analysis, such as geochemical maps, cumulative frequency diagrams, boxplots and scatterplots, are used to interpret the origin of the patterns for these elements. None of the elements reported here are emitted in significant amounts from the smelting industry on the Kola Peninsula. Despite the conventional view that moss chemistry reflects atmospheric element input, the nature of the underlying mineral substrate (regolith or bedrock) is found to have a considerable influence on moss composition for several elements. This influence of the chemistry of the mineral substrate can take place in a variety of ways. (1) It can be completely natural, reflecting the ability of higher plants to take up elements from deep soil horizons and shed them with litterfall onto the surface. (2) It can result from naturally increased soil dust input where vegetation is scarce due to harsh climatic conditions for instance. Alternatively, substrate influence can be enhanced by human activity, such as open-cast mining, creation of ‘technogenic deserts’, or handling, transport and storage of ore and ore products, all of which magnify the natural elemental flux from bedrock to ground vegetation. Seaspray is another natural process affecting moss composition in the area (Mg, Na), and this is most visible in the Norwegian part of the study area. Presence or absence of some plant species, e.g., lichens, seems to influence moss chemistry. This is shown by the low concentrations of B or K in moss on the Finnish and Norwegian side of the (fenced) border with Russia, contrasting with high concentrations on the other side (intensive reindeer husbandry west of the border has selectively depleted the lichen population).  相似文献   

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This paper discusses the result of the detailed investigations carried out on the coal characteristics, including coal petrography and its geochemistry of the Pabedana region. A total of 16 samples were collected from four coal seams d2, d4, d5, and d6 of the Pabedana underground mine which is located in the central part of the Central-East Iranian Microcontinent. These samples were reduced to four samples through composite sampling of each seam and were analyzed for their petrographic, mineralogical, and geochemical compositions. Proximate analysis data of the Pabedana coals indicate no major variations in the moisture, ash, volatile matter, and fixed carbon contents in the coals of different seams. Based on sulfur content, the Pabedana coals may be classified as low-sulfur coals. The low-sulfur contents in the Pabedana coal and relatively low proportion of pyritic sulfur suggest a possible fresh water environment during the deposition of the peat of the Pabedana coal. X-ray diffraction and petrographic analyses indicate the presence of pyrite in coal samples. The Pabedana coals have been classified as a high volatile, bituminous coal in accordance with the vitrinite reflectance values (58.75–74.32 %) and other rank parameters (carbon, calorific value, and volatile matter content). The maceral analysis and reflectance study suggest that the coals in all the four seams are of good quality with low maceral matter association. Mineralogical investigations indicate that the inorganic fraction in the Pabedana coal samples is dominated by carbonates; thus, constituting the major inorganic fraction of the coal samples. Illite, kaolinite, muscovite, quartz, feldspar, apatite, and hematite occur as minor or trace phases. The variation in major elements content is relatively narrow between different coal seams. Elements Sc,, Zr, Ga, Ge, La, As, W, Ce, Sb, Nb, Th, Pb, Se, Tl, Bi, Hg, Re, Li, Zn, Mo, and Ba show varying negative correlation with ash yield. These elements possibly have an organic affinity and may be present as primary biological concentrations either with tissues in living condition and/or through sorption and formation of organometallic compounds.  相似文献   

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The Kuskokwim River at Bethel, Alaska, drains a major mercury-antimony metallogenic province in its upper reaches and tributaries. Bethel (population 4000) is situated on the Kuskokwim floodplain and also draws its water supply from wells located in river-deposited sediment. A boring through overbank and floodplain sediment has provided material to establish a baseline datum for sediment-hosted heavy metals. Mercury (total), arsenic, antimony, and selenium contents were determined; aluminum was also determined and used as normalizing factor. The contents of the heavy metals were relatively constant with depth and do not reflect any potential enrichment from upstream contaminant sources.  相似文献   

20.
《Chemical Geology》2007,236(1-2):13-26
We examined the coprecipitation behavior of Ti, Mo, Sn and Sb in Ca–Al–Mg fluorides under two different fluoride forming conditions: at < 70 °C in an ultrasonic bath (denoted as the ultrasonic method) and at 245 °C using a Teflon bomb (denoted as the bomb method). In the ultrasonic method, small amounts of Ti, Mo and Sn coprecipitation were observed with 100% Ca and 100% Mg fluorides. No coprecipitation of Ti, Mo, Sn and Sb in Ca–Al–Mg fluorides occurred when the sample was decomposed by the bomb method except for 100% Ca fluoride. Based on our coprecipitation observations, we have developed a simultaneous determination method for B, Ti, Zr, Nb, Mo, Sn, Sb, Hf and Ta by Q-pole type ICP-MS (ICP-QMS) and sector field type ICP-MS (ICP-SFMS). 9–50 mg of samples with Zr–Mo–Sn–Sb–Hf spikes were decomposed by HF using the bomb method and the ultrasonic method with B spike. The sample was then evaporated and re-dissolved into 0.5 mol l 1 HF, followed by the removal of fluorides by centrifuging. B, Zr, Mo, Sn, Sb and Hf were measured by ID method. Nb and Ta were measured by the ID-internal standardization method, based on Nb/Mo and Ta/Mo ratios using ICP-QMS, for which pseudo-FI was developed and applied. When 100% recovery yields of Zr and Hf are expected, Nb/Zr and Ta/Hf ratios may also be used. Ti was determined by the ID-internal standardization method, based on the Ti/Nb ratio from ICP-SFMS. Only 0.053 ml sample solution was required for measurement of all 9 elements. Dilution factors of ≤ 340 were aspirated without matrix effects. To demonstrate the applicability of our method, 4 carbonaceous chondrites (Ivuna, Orgueil, Cold Bokkeveld and Allende) as well as GSJ and USGS silicate reference materials of basalts, andesites and peridotites were analyzed. Our analytical results are consistent with previous studies, and the mean reproducibility of each element is 1.0–4.6% for basalts and andesites, and 6.7–11% for peridotites except for TiO2.  相似文献   

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