共查询到20条相似文献，搜索用时 31 毫秒
1.
Synthesis and Preliminary Characterisation of New Silicate, Phosphate and Titanite Reference Glasses 总被引：3，自引：0，他引：3
Stephan Klemme Stefan Prowatke Carsten Münker Charles W. Magee Yann Lahaye Thomas Zack Simone A. Kasemann E. Joan A. Cabato Benjamin Kaeser 《Geostandards and Geoanalytical Research》2008,32(1):39-54
Eleven synthetic silicate and phosphate glasses were prepared to serve as reference materials for in situ microanalysis of clinopyroxenes, apatite and titanite, and other phosphate and titanite phases. Analytical results using different micro-analytical techniques showed that the glass fragments were homogeneous in major and trace elements down to the micrometre scale. Trace element determinations using inductively coupled plasma-mass spectrometry (ICP-MS), multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS), laser-ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) and secondary ionisation mass spectrometry (SIMS) showed good agreement for most elements (Li, Be, B, Cs, Rb, Ba, Sr, Ga, Pb, U, Th, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Er, Tm, Yb, Lu, Zr, Hf, Ta, Nb) studied and provide provisional recommended values. 相似文献
2.
Laser Ablation ICP-MS Analysis of Geological Materials Prepared as Lithium Borate Glasses 总被引：9，自引：0，他引：9
Stephen M. Eggins 《Geostandards and Geoanalytical Research》2003,27(2):147-162
A simple, rapid and precise method is described for determining trace elements by laser ablation (LA)-ICP-MS analysis in bulk geological materials that have been prepared as lithium borate glasses following standard procedures for XRF analysis. This approach reliably achieves complete sample digestion and provides for complementary XRF and LA-ICP-MS analysis of a full suite of major and trace elements from a single sample preparation. Highly precise analysis is enabled by rastering an ArF excimer laser (λ= 193nm) across fused samples to deliver a constant sample yield to the mass spectrometer without inter-element fractionation effects during each analysis. Capabilities of the method are demonstrated by determination of twenty five trace elements (Sc, Ti, V, Ga, Rb, Sr, Y, Zr, Nb, Cs, Ba, REE, Hf, Ta, Pb, Th and U) in a diverse range of geological reference materials that includes peridotites, basalts, granites, metamorphic rocks and sediments. More than 90% of determinations are indistinguishable from published reference values at the 95% confidence level. Systematic bias greater than 5% is observed for only a handful of elements (Zr, Nb and U) and may be attributed in part to inaccurate calibration values used for the NIST SRM 612 glass in the case of Zr and Nb. Detection limits for several elements, most notably La, are compromised at ultra-trace levels by impurities in the lithium borate flux but can be corrected for by subtracting appropriate procedural blanks. Reliable Pb analysis has proved problematic due to variable degrees of contamination introduced during sample polishing prior to analysis and from Pt-crucibles previously used to fuse Pb-rich samples. Scope exists for extending the method to include internal standard element/isotope spiking, particularly where integrated XRF analysis is not available to characterise major and trace elements in the fused lithium borate glasses prior to LA-ICP-MS analysis. 相似文献
3.
V. B. Naumov V. A. Dorofeeva A. V. Girnis V. V. Yarmolyuk 《Geochemistry International》2014,52(5):347-364
Using our database on major, trace, and volatile element contents in melt inclusions in minerals and quenched glasses of volcanic rocks reported in the literature, we compared the mean contents of 71 chemical elements in melts from the mid-ocean ridges (MORB) of the Atlantic, Pacific, and Indian oceans and determined the mean MORB composition for all the oceans of the Earth (global MORB composition). Mean ratios of incompatible trace and volatile components (H2O/Ce, K2O/Cl, Nb/U, Ba/Rb, Ce/Pb, Nb/U, etc.) were calculated for magmatic melts from all the oceans. Variations of these parameters were estimated, and significant differences between the melts of the Atlantic and Pacific oceans were established. 相似文献
4.
Trace element partitioning between apatite and silicate melts 总被引：7，自引：0，他引：7
We present new experimental apatite/melt trace element partition coefficients for a large number of trace elements (Cs, Rb, Ba, La, Ce, Pr, Sm, Gd, Lu, Y, Sr, Zr, Hf, Nb, Ta, U, Pb, and Th). The experiments were conducted at pressures of 1.0 GPa and temperatures of 1250 °C. The rare earth elements (La, Ce, Pr, Sm, Gd, and Lu), Y, and Sr are compatible in apatite, whereas the larger lithophile elements (Cs, Rb, and Ba) are strongly incompatible. Other trace elements such as U, Th, and Pb have partition coefficients close to unity. In all experiments we found DHf > DZr, DTa ≈ DNb, and DBa > DRb > DCs. The experiments reveal a strong influence of melt composition on REE partition coefficients. With increasing polymerisation of the melt, apatite/melt partition coefficients for the rare earth elements increase for about an order of magnitude. We also present some results in fluorine-rich and water-rich systems, respectively, but no significant influence of either H2O or F on the partitioning was found. Furthermore, we also present experimentally determined partition coefficients in close-to natural compositions which should be directly applicable to magmatic processes. 相似文献
5.
吉南老岭地区早白垩世铝质A型花岗岩的厘定及其构造意义 总被引：1，自引：0，他引：1
主微量元素分析和LA-ICP-MS锆石U-Pb年龄显示吉南老岭地区的头道、老岭、上绿水桥和高台子岩体为一套早白垩世铝质A型花岗岩.主要岩性为钾长花岗岩、晶洞钾长花岗岩、花岗斑岩和花岗岩.LA-ICP-MS锆石U-Pb年龄为121~125Ma.主量元素具有富Si、alk, 贫Fe、Mg、Ca、Ti的特征; 微量元素亏损Ba、Sr、Ti、Nb、Ta、P, 富集K、Rb、Th等不相容元素; 稀土元素具有中等到强烈的负铕异常及右倾海鸥型的球粒陨石标准化稀土配分模式.元素地球化学特征表明岩体为铝质A型花岗岩(A/CNK=0.82~1.15, A/NK=1.00~1.28).岩石具有较低的不相容元素Ce/Nb、Y/Nb、Yb/Ta比值, 为A1型非造山花岗岩.研究表明吉南老岭地区早白垩世时处于非造山的伸展构造环境, 是华北板块东部早白垩世伸展地球动力学背景在吉林南部地区的岩浆活动体现. 相似文献
6.
Alessia Borghini Silvio Ferrero Patrick J. O’Brien Oscar Laurent Christina Günter Martin A. Ziemann 《Journal of Metamorphic Geology》2020,38(3):207-234
Garnet of eclogite (formerly termed garnet clinopyroxenite) hosted in lenses of orogenic garnet peridotite from the Granulitgebirge, NW Bohemian Massif, contains unique inclusions of granitic melt, now either glassy or crystallized. Analysed glasses and re-homogenized inclusions are hydrous, peraluminous, and enriched in highly incompatible elements characteristic of the continental crust such as Cs, Li, B, Pb, Rb, Th, and U. The original melt thus represents a pristine, chemically evolved metasomatic agent, which infiltrated the mantle via deep continental subduction during the Variscan orogeny. The bulk chemical composition of the studied eclogites is similar to that of Fe-rich basalt and the enrichment in LILE and U suggest a subduction-related component. All these geochemical features confirm metasomatism. In comparison with many other garnet+clinopyroxene-bearing lenses in peridotites of the Bohemian Massif, the studied samples from Rubinberg and Klatschmühle are more akin to eclogite than pyroxenites, as reflected in high jadeite content in clinopyroxene, relatively low Mg, Cr, and Ni but relatively high Ti. However, trace elements of both bulk rock and individual mineral phases show also important differences making these samples rather unique. Metasomatism involving a melt requiring a trace element pattern very similar to the composition reported here has been suggested for the source region of rocks of the so-called durbachite suite, that is, ultrapotassic melanosyenites, which are found throughout the high-grade Variscan basement. Moreover, the Th, U, Pb, Nb, Ta, and Ti patterns of these newly studied melt inclusions (MI) strongly resemble those observed for peridotite and its enclosed pyroxenite from the T-7 borehole (Staré, České Středhoři Mountains) in N Bohemia. This suggests that a similar kind of crustal-derived melt also occurred here. This study of granitic MI in eclogites from peridotites has provided the first direct characterization of a preserved metasomatic melt, possibly responsible for the metasomatism of several parts of the mantle in the Variscides. 相似文献
7.
Anastassia Yu. Borisova Michel Pichavant Michael Wiedenbeck Frédéric Candaudap 《Geochimica et cosmochimica acta》2006,70(14):3702-3716
The dacite pumice erupted from Mt. Pinatubo on June 15, 1991 (whole-rock, rhyolitic groundmass glasses and homogenized melt inclusions) has been analyzed using inductively coupled plasma-mass spectrometry (ICP-MS), nanosecond and femtosecond laser ablation ICP-MS and secondary ion mass spectrometry (SIMS) to evaluate its ore-forming potential. Data suggest that adakite magmas are metal-rich and concentrate ore metals during magmatic differentiation. Sulfides segregate in limited amounts under the hydrous, oxidizing conditions typical of adakitic magmas resulting in incompatible behavior for Au (6-22 ppb), Cu (26-77 ppm), and Pb, Mo, As, and Sb in melts of dacitic to rhyolitic compositions. Metal transfer from this adakite magma to the coexisting aqueous phase was favored by the peraluminous composition of the rhyolitic melt and high aqueous chloride concentrations. Mass balance calculations suggest that the pre-eruptive aqueous phase could have extracted a minimum of 100 t Au and 5 × 105 t Cu from the Mt. Pinatubo magma. Our data suggest that intrusives having adakitic signatures are genetically associated with Au-Cu and Cu-Mo mineralization, auriferous porphyry copper deposits, and epithermal gold veins. High H2O, Cl, Sr/Y, Pb/Ce, Mo/Ce, As/Ce and Sb/Ce in Mt. Pinatubo melts reflect the contribution of deep fluids derived from subducted sediments and altered MORBs in the dacite genesis. The slab-derived fluids carrying mobile elements are likely responsible for the enrichment of adakite magmas in gold, associated metals and H2O, and may explain the exceptional ore-forming potential of adakite magmatism. 相似文献
8.
New trace element data were obtained by ICP-MS for 58 samples representing eight intrusive phases of the Raumid granite Pluton. All of the rocks, except for one sample that was deliberately taken from a greisenized zone, were not affected by postmagmatic fluid alteration. The sequential accumulation of incompatible trace elements (Rb, Ta, Nb, Pb, U, and others) in the Raumid Pluton from the early to late phases coupled with a decrease in incompatible element contents (Sr, Eu, Ba, and others) indicates a genetic link between the granites of all phases via fractional crystallization of a granite melt. The REE distribution patterns of final granite phases are typical of rare-metal granites. The Ta content in the granites of phase 8 is only slightly lower than that of typical rare-metal granites. Greisenization disturbed the systematic variations in trace element distribution formed during the magmatic stage. The ranges of trace element contents (Rb, Sr, Ta, Nb, and others) and ratios (Rb/Sr, La/Lu, Eu/Eu*, and others) in the Raumid granite overlap almost entirely the ranges of granitic rocks of various compositions, from the least differentiated with ordinary trace element contents to rare-metal granites. This indicates that the geochemical signature of rare-metal granites can develop at the magmatic stage owing to fractional crystallization of melts, which is the case for the melt of the Raumid granite. 相似文献
9.
俯冲玄武质洋壳的部分熔融作用是一种重要的大陆生长作用，但是陆壳物质在俯冲过程中能否发生部分熔融缺少直接的证据。笔者利用已有的微量元素分配系数，讨论了岛弧玄武岩在脱水和部分熔融2种过程中微量元素行为和铅同位素演化的差异。Pb在2种过程中都属于不相容元素，但在脱水过程中其不相容性明显高于Rb、Ba、Th、U，而在熔融过程中则低于上述元素，在ω(Rb)/ω(Pb)-ω(Rb)、ω（Ba)/ω(Pb)-ω(Ba)、ω（Th)/ω(Pb)-ω(Th)、ω（U）／ω(Pb)-ω(U)相关图上2种过程的演化方向差别明显。此外，Pb和Th、U的相容性的差异也使得石榴石和绿辉石的单矿物铅同位素在2种过程中明显不同。在此基础上，结合大别－苏鲁榴辉岩的实测数据，认为大别－苏鲁榴辉岩可能部分是岛弧玄武岩部分熔融后的残余体，部分为单纯脱水的产物。大陆玄武质岩石在俯冲过程中也可能发生部分熔融作用。 相似文献
10.
XRF AND INAA DETERMINATIONS OF MAJOR AND TRACE ELEMENTS IN GEOLOGICAL SURVEY OF JAPAN IGNEOUS AND SEDIMENTARY ROCK STANDARDS 总被引：1，自引：0，他引：1
Major and trace element analyses have been obtained by wavelength dispersive X-ray fluorescence for the Geological Survey of Japan Igneous rock series and selected samples from the Sedimentary rock series reference samples. Additional trace element data for the Igneous rock series were obtained by instrumental neutron activation analysis. Samples were analyzed multiple times for 10 major elements (with loss-on-ignition) and the following trace elements; As, Ba, Ce, Co, Cr, Cs, Cu, Eu, Ga, Hf, La, Lu, Nb, Nd, Ni, Pb, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, U, V, W, Y, Yb, Zn and Zr. 相似文献
11.
甘肃北山小西弓金矿区石英正长斑岩LA-ICP-MS锆石U-Pb年龄和地球化学特征 总被引：1，自引：0，他引：1
通过高精度的LA-ICP-MS锆石U-Pb测年,获得北山南带小西弓金矿区石英正长斑岩的形成年龄为247.5±2.2Ma,属中三叠世。地球化学分析表明,该岩体为准铝质、钾玄岩系列,主量元素高硅(Si O_2=65.8%~66.2%)、富碱(Na_2O+K_2O=8.99%~9.41%)、低钙(Ca O=1.72%~2.19%)、贫镁(Mg O=0.63%~0.70%);轻稀土元素富集,重稀土元素亏损,弱负Eu异常。大离子亲石元素Rb、Th、U、K和Pb富集,同时Ba、Sr、P、Ti和Eu亏损,并具高104*Ga/Al值和高Zr+Nb+Ce+Y含量,表现出A型花岗岩的特征。北山南带三叠纪岩浆活动强烈,高分异I型-A型花岗岩大量发育,暗示区域内三叠纪处于造山后伸展环境。 相似文献
12.
H. B. West M. O. Garcia F. A. Frey A. Kennedy 《Contributions to Mineralogy and Petrology》1988,100(3):383-397
Most Hawaiian basaltic shield volcanoes are capped by moderately to strongly evolved alkalic lavas (MgO<4.5 wt.%). On Mauna Kea Volcano the cap is dominantly composed of hawaiite with minor mugearite. Although these lavas contain dunite and gabbroic xenoliths, they are nearly aphyric with rare olivine and plagioclase phenocrysts and xenocrysts. The hawaiites are nearly homogeneous in radiogenic isotope ratios (Sr, Nd, Pb) and they define coherent major and trace element abundance trends. These compositional trends are consistent with segregation of a plagioclase-rich cumulate containing significant clinopyroxene and Fe-Ti oxides plus minor olivine. Elements which are usually highly incompatible, e.g., Rb, Ba, Nb, are only moderately incompatible within the hawaiite suite because these elements are incorporated into feldspar (Rb, Ba) and oxides (Nb). However, in the most evolved lavas abundances of the most incompatible elements (P, La, Ce, Th) exceed (by 5–10%) the maximum enrichments expected from models based on major elements. Apparently, the crystal fractionation process was more complex than simple, closed system fractionation. The large amounts of clinopyroxene in the fractionating assemblage and the presence of dense dunite xenoliths with CO2 inclusions formed at minimum pressures of 2 kb are consistent with fractionation occurring at moderate depths. Crystal segregation along conduit or magma chamber walls is a possible mechanism for explaining compositional variations within these alkalic cap lavas. 相似文献
13.
通过对龙王山灰白色细粒石英闪长岩和灰白色细粒二长花岗岩样品进行LA-ICP-MS锆石U-Pb测年结果属于晚志留世侵入岩。岩石地球化学特征表明,为高钾过铝质-准铝质碱钙性岩;稀土元素Eu具有弱负异常特征;微量元素中Ta、Nb、gr、Sr、Ti、P相对贫化,Rb、Th、Hf、Ba、Sc、K、Ce、Nd、Sm含量相对富集。Rb／Sr平均值为0．30,介于上地幔值与地壳值之间,反映出壳幔源的特点,为s型花岗岩。综合分析该期花岗岩是弧陆碰撞向陆陆碰撞转化阶段构造背景下形成的同碰撞花岗岩。 相似文献
14.
By the example of the Orlovka massif of Li-F granites in Eastern Transbaikalia, the major- and trace-element (Li, Be, B, Ta,
Nb, W, REE, Y, Zr, and Hf) compositions of the parental melt and the character of its variations during the formation of the
differentiated rock series were quantitatively estimated for the first time on the basis of electron and ion microprobe analysis
and Raman spectroscopy of rehomogenized glasses of melt inclusions in quartz. It was shown that the composition of the Orlovka
melt corresponded to a strongly evolved alumina-saturated granitoid magma (A/CNK = 1.12–1.55) rich in normative albite, poor
in normative quartz, and similar to ongonite melts. This magma was strongly enriched in water (up to 9.9 ± 1.1 wt %) and fluorine
(up to 2.8 wt %). Most importantly, this massif provided the first evidence for high B2O3 contents in melts (up to 2.09 wt %). The highest contents of trace elements were observed in the melt from pegmatoid bodies
in the amazonite granites of the border zone: up to 5077 ppm Li, 6397 ppm Rb, 313 ppm Cs, 62 ppm Ta, 116 ppm Nb, and 62 ppm
W. Compared with the daughter rock, the Orlovka melt was depleted at all stages of formation in SiO2 (by up to 6 wt %), Na2O (by up to 2.5 wt %), and, to a smaller extent, in Ti, Fe, Mg, Sr, and Ba, but was enriched in Mn, Rb, F, B, and H2O. 相似文献
15.
为了解酸性矿山排水（AMD）影响下水库沉积物中微量元素的质量分数水平及其分布特征,对常年受酸性废水影响的贵州兴仁猫石头水库沉积物中26种微量元素的质量分数、相关性及控制因素进行了分析。结果表明：猫石头水库沉积物柱中Sr、Ba、Zr、V、Cr和As质量分数平均值超过了100 μg/g,其中As质量分数最高,平均值超过800 μg/g;Be、Ta、Co、Ag、Cd、Sn和Se质量分数的平均值都在5 μg/g以下;其他元素质量分数平均值则在10~60 μg/g之间。相较未受AMD影响的水系沉积物,研究区水库沉积物具有明显的As和Sb富集特征。水库沉积物中Li、Be、Rb、Sr、Cs、Ba、Sc、Y、Zr、Hf、Nb、Ta、Th之间存在显著正相关关系,而As与这些元素之间存在显著负相关关系。元素相关分析、因子分析及微量元素图解表明,Li、Be、Rb、Sr、Cs、Ba、Sc、Y、Zr、Hf、Nb、Ta、Th、Cr、Sb等元素受控于流域岩石化学风化和土壤物理侵蚀,这也是控制研究区元素分布最重要的因素,而Cu、Cd等重金属元素则与AMD对地层中元素的溶蚀析出和有机质等细颗粒物的吸附有关。另外,研究区重金属元素中,Cd、Cu、Pb、Cr、Zn的生态风险轻微,而As和Sb则具有很强的潜在生态风险。 相似文献
16.
浙西开化地区皖浙边界断裂带西侧浅变质岩系中发育了一套以流纹岩为主的酸性火山岩。两个流纹岩样品的锆石LA-ICP-MS U-Pb定年分别给出了785±5 Ma和781±10 Ma的结果,显示为南华裂谷期的产物。岩石地球化学分析显示:该流纹岩富硅偏碱,铝饱和指数A/CNK大于1.11,显示过铝质特点;稀土元素总量高,相对富集轻稀土元素,具中等Eu负异常;相对富集Rb、Th、U、Pb等强不相容元素,而相对亏损亲石元素Ba、Sr、Nb、Ta,Zr含量较高。与壳源花岗质岩浆的地球化学特征相似。在微量元素构造判别图中显示为板内火山岩。结合地质背景分析,认为其形成于大陆裂谷环境,可能与华南地幔柱活动有关。 相似文献
17.
Analytical data on 34 geochemically significant trace elements (Sc, V, Cr, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Cs, Ba, Hf, Ta, Pb, The, U and REE) by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS), for 13 reference rock samples obtained from the Geological Survey of Finland are presented. For many elements, especially most of the heavy-REE, concentrations are reported here for the first time. 相似文献
18.
用X-荧光光谱测定岩石中低量稀土元素的仪器参数和测定条件,文[1]已作过讨论。本文介绍样品分析所采用的基本校正,谱线重叠校正和背景处理方法,并将这些方法应用于其他少量和痕量元素的测定。基体的吸收校正岩石样品中最重的主元素是铁,镧系元素La～Er的La线和Ti,Sc,Cr,Mn,Fe, 相似文献
19.
本文对苏北地区锦屏组磷矿石及地层样品进行了岩相学及地球化学分析,研究了磷矿初始沉积环境和源区特征。磷矿类微量元素富集Ba、Pb、U、Sr,贫Th、Ta、Nb、Ti;REE配分曲线为LREE富集型,Ce负异常,表明成矿环境为陆缘海,且成矿过程受深海热水沉积和生物作用影响。Sr、Nd同位素初始值判断磷灰岩物质来源为年轻的地壳物质。绿片岩类微量元素富集Rb、Th、K,贫Th、U、Ta、Nb、Sr、Ti;REE配分曲线为LREE富集型,判断其原岩为陆源碎屑岩。（混合）片麻岩类微量元素富集Pb、Th、K,亏损Ba、Ta、Nb、Sr、Ti;REE配分曲线为LREE富集型,具地幔源区特征。 相似文献
20.
V. B. Naumov V. A. Dorofeeva A. V. Girnis V. V. Yarmolyuk 《Geochemistry International》2017,55(7):629-653
Mean concentrations of major components, trace elements, and volatile components in magmatic melts from Earth’s major geodynamic environments are estimated using our database (which comprises more than 1200000 analyses for 75 chemical elements—state for the beginning of 2016) on melt inclusions and quench glasses of rocks). The geodynamic environments are classified into (I) environments of oceanic plate spreading (mid-oceanic ridges), (II) areas affected by mantle plumes in oceanic plates (oceanic islands and lava plateaus), (III and IV) subduction-related environments (III are magmatic zones in island arcs, and IV are magmatic zones in active continental margins, in which magma-generating processes involve the continental crust), (V) continental rifts in areas with continental hotspots, and (VI) backarc spreading zones. The distribution of SiO2 concentrations (>71000 analyses) in natural magmatic melts in all geodynamic environments is obviously bimodal, with maxima at 50–52 and 72–76 wt % SiO2. Herein we discuss only mafic melts (40–54 wt % SiO2). Mean concentrations and confidence levels are calculated for each geodynamic environment for the first time in three variants: from melt inclusions in minerals, from quench glasses in rocks, and from all data. Systematic variations in the mean compositions of melt inclusions and glasses in rocks are detected for all geodynamic environments. Primitive mantle-normalized multielemental patterns for mean concentrations of elements are constructed for magmatic melts from all geodynamic environments, and the mean ratios and their variations are calculated for trace incompatible and volatile components (H2O/Ce, K2O/Cl, La/Y, Nb/U, Ba/Rb, Ce/Pb, etc.) in melts from all environments. 相似文献