scholarly journals Relation between cathodoluminescence and trace-element distribution of magmatic topaz from the Ary-Bulak massif, Russia

2016 ◽  
Vol 80 (5) ◽  
pp. 881-899 ◽  
Author(s):  
Andrea Agangi ◽  
Arnold Gucsik ◽  
Hirotsugu Nishido ◽  
Kiyotaka Ninagawa ◽  
Vadim S. Kamenetsky
Keyword(s):  
Trace Element ◽  
Inductively Coupled Plasma ◽  
Analytical Techniques ◽  
Trace Element Composition ◽  
Element Distribution ◽  
Trace Element Distribution ◽  
Clear Correlation ◽  
Cell Parameters ◽  
Near Ultraviolet ◽  
Stretching Vibration

AbstractIn order to define the cathodoluminescence (CL) properties of magmatic topaz and its relation with trace-element composition, we studied topaz phenocrysts from the Ary-Bulak ongonite massif, Russia using a wide array of analytical techniques. Scanning electron microscopy CL panchromatic images reveal strong variations, which define micrometre-scale euhedral growth textures. Several truncations of these growth textures occur in single grains implying multiple growth and resorption events. The CL-spectra of both CLbright and -dark domains have a major peak in the near-ultraviolet centred at 393 nm. Cathodoluminescence images taken after several minutes of electron bombardment show decreasing emission intensity. Electron microprobe analyses indicate high F concentrations (average OH/(OH + F) = 0.04 calculated by difference, 100 wt.% – total from electron probe microanalyses), consistent with what has been found previously in topaz-bearing granites, and the OH stretching vibration (∼3653 cm–1) was detected in Raman spectra. Laser ablation inductively-coupled plasma mass spectrometry traverses performed across the CL textures detected trace elements at ppm to thousands of ppm levels, including: Fe, Mn, Li, Be, B, P, Nb, Ta, W, Ti, Ga, light rare-earth elements, Th and U. Lithium, W, Nb and Ta appear to be correlated with CL intensity, suggesting a role for some of these elements in the activation of CL in topaz. In contrast, no clear correlation was found between CL intensity and F contents, despite the fact that the replacement of OH for F is known to affect the cell parameters of topaz.

scholarly journals Trace-Element Distribution on Sulfide Mineralization in Trento Province, NE Italy

Minerals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 736
Author(s):  
Gianluca Bianchini ◽  
Claudio Natali ◽  
Paolo Ferretti ◽  
Lara Casagrande ◽  
Manuel Conedera ◽  
...  
Keyword(s):  
Trace Element ◽  
Middle Ages ◽  
Inductively Coupled Plasma ◽  
Analytical Data ◽  
Element Distribution ◽  
Trace Element Distribution ◽  
Sulfide Mineralization ◽  
High Concentration ◽  
Thin Sections ◽  
Local Soil

Sulfide mineralization in the province of Trento (northeastern Italy) includes various mineral assemblages that are often silver-rich and have been exploited in different phases from the Middle Ages until the 20th century. This study investigates mineralized rocks from three historically important sites (Calisio mount, Erdemolo lake, and the locality of Cinque Valli), providing new analytical data (Inductively Coupled Plasma-Mass Spectrometry on bulk rocks, and Scanning Electron Microscopy on thin sections) that demonstrate that parageneses do not only include galena, chalcopyrite, and sphalerite but also accessory minerals, such as tetrahedrite, tennantite, acanthite, and sulfosalts (matildite/polybasite). This explains the high content of As (up to 278 ppm), Bi (up to 176 ppm), and Sb (up to 691 ppm) that are associated with Pb–Cu–Zn mineralization. Notably, trace-element ratios indicate that, although closely associated from a geographical point of view, the studied sites are not genetically related and have to be referred to in distinct mineralization events, possibly induced by three diverse magmatic and hydrothermal phases that occurred in the Variscan post-orogenic setting. Besides geological and petrogenetic reconstruction, the new data outline potential geochemical risks, as they reveal a high concentration of elements characterized by marked toxicity that can be transferred into the local soil and water. Therefore, future studies should be devoted to better investigating the metal distribution in the surroundings of ancient mining sites and their geochemical behavior during the weathering processes.

Growth, replacement and element diffusion in metamorphic garnet revealed by trace element mapping 

2021 ◽  
Author(s):  
Daniela Rubatto ◽  
Lanari Pierre ◽  
Marcel Burger ◽  
Bodo Hattendorf ◽  
Gunnar Schwarz ◽  
...  
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Inductively Coupled Plasma ◽  
Major Elements ◽  
Element Distribution ◽  
Garnet Growth ◽  
Trace Element Distribution ◽  
Rock Interaction ◽  
Growth Zoning ◽  
Element Mapping

<p>Garnet is one of the most robust and ubiquitous minerals that record element zoning during crustal metamorphism. In addition to major element distribution, zoning in trace elements can provide a wealth of information to document the changing conditions of garnet growth and modification. Trace element distribution in garnet grains was mapped in 2D in thin section with laser ablation inductively coupled plasma time of flight mass spectrometry (LA-ICP-TOFMS) and conventional LA-ICP-MS to achieve a lateral resolution of 15-5 µm and limits of detection for the heavy rare earth elements (REE) down to 0.2 µg/g (Rubatto et al. 2020).</p><p>In granulite-facies garnet, major elements show diffusional resetting, whereas trace elements still largely document the growth history. Enrichment of trace elements in the garnet mantle is attributed to the consumption of biotite (V, Cr) and the dissolution of zircon (Zr) and monazite (Y+REE) in the coexisting melt. Lu is notably enriched in the garnet mantle with implications for geochronology. The gradual zoning of Y+HREE between mantle and core is reconcilable with diffusion over ~200 µm in 10 My at temperatures of 750–800°C</p><p>In amphibolite facies garnet, Y+REE trace element zoning closely matches the growth zoning in Ca with no notable diffusive modification. Y+REE zoning is dominated by Rayleigh fractionation in the core and in the outer zones it shows annuli that mark the sporadic breakdown of accessory phases.</p><p>Garnet in eclogite facies samples that underwent fluid-rock interaction show growth zoning in major and trace elements, with local oscillations and sectors. In certain samples, the overall distribution of REE can be reconciled with diffusion-limited uptake. Where garnet displays fluid-related veinlets, visible in major elements, that cross-cut the primary growth zoning, the regular Y+REE and Cr growth zoning is not affected by the veinlets. This indicates that the veinlets did not form by a crack-seal mechanism but are rather related to a selective replacement process.</p><p> </p><p><strong>References </strong></p><p>Rubatto D, Burger M, Lanari P, Hattendorf B, Schwarz G, Neff C, Keresztes Schmidt P, Hermann J, Vho A, Günther D (2020) Identification of growth mechanisms in metamorphic garnet by high-resolution trace element mapping with LA-ICP-TOFMS. Contrib Mineral Petrol 175:61 doi.org/10.1007/s00410-020-01700-5</p>

Methylmercury and Trace Element Distribution in the Organs of Stenella coeruleoalba Dolphins Stranded on the French Mediterranean Coast

2014 ◽  
Vol 8 (1) ◽  
pp. 35-48 ◽  
Author(s):  
Emmanuel Wafo ◽  
Véronique Risoul ◽  
Thérèse Schembri ◽  
Véronique Lagadec ◽  
Frank Dhermain ◽  
...  
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Marine Pollution ◽  
Element Distribution ◽  
Mediterranean Coast ◽  
Trace Element Distribution ◽  
Slight Reduction ◽  
Stenella Coeruleoalba ◽  
Contamination Levels

The main objective of this study was to evaluate the contamination by mercury (Hg), methylmercury (Me-Hg), cadmium (Cd), selenium (Se), zinc (Zn), copper (Cu), iron (Fe) and manganese (Mn) in dolphins stranded on the French Mediterranean coast. The distributions of these contaminants in the organs of dolphins have also been studied. Overall, contamination levels varied according to the following sequence: liver > kidney > lung > muscle, except for cadmium (kidney > liver > lung > muscle). Size and sex of animals were also considered. Young dolphins were less impacted with trace elements than adults, except for copper. Among the studied parameters, the most important appeared to be the size of mammals. In addition, in the case of mercury and selenium, the sex of mammals seemed to be also relevant. The correlations between the concentrations of trace elements suggest the existence of detoxification processes. Since 1990s, using dolphins for tracing marine pollution, a slight reduction in the burden of the considered trace elements could be noted.

TRACE-ELEMENT DISTRIBUTION IN GIANT SPODUMENE CRYSTALS IN GRANITIC PEGMATITES FROM THE BLACK HILLS, SOUTH DAKOTA AND NEWRY, MAINE

2019 ◽  
Author(s):  
Stephan R. Hlohowskyj ◽  
◽  
Mona-Liza C. Sirbescu ◽  
James J. Student ◽  
Niels Hulsbosch ◽  
...  
Keyword(s):  
South Dakota ◽  
Trace Element ◽  
Element Distribution ◽  
Black Hills ◽  
Trace Element Distribution ◽  
Granitic Pegmatites

Major- and trace-element composition of REE-rich turkestanite from peralkaline granites of the Morro Redondo Complex, Graciosa Province, south Brazil

2010 ◽  
Vol 74 (4) ◽  
pp. 645-658 ◽  
Author(s):  
F. C. J. Vilalva ◽  
S. R. F. Vlach
Keyword(s):  
Trace Element ◽  
Inductively Coupled Plasma ◽  
Alkali Feldspar ◽  
Trace Element Composition ◽  
Inductively Coupled ◽  
Coupled Substitution ◽  
Plasma Mass Spectrometry ◽  
Compositional Variations ◽  
End Members ◽  
South Brazil

AbstractTurkestanite, a rare Th- and REE-bearing cyclosilicate in the ekanite–steacyite group was found in evolved peralkaline granitesfrom the Morro Redondo Complex, south Brazil. It occurswith quartz, alkali feldspar and an unnamed Y-bearing silicate. Electron microprobe analysis indicates relatively homogeneous compositions with maximum ThO2, Na2O and K2O contentsof 22.4%, 2.93% and 3.15 wt.%, respectively, and significant REE2O3 abundances(5.21 to 11.04 wt.%). The REE patterns show enrichment of LREE over HREE, a strong negative Eu anomaly and positive Ce anomaly, the latter in the most transformed crystals. Laser ablation inductively coupled plasma mass spectrometry trace element patterns display considerable depletions in Nb, Zr, Hf, Ti and Li relative to whole-rock sample compositions. Observed compositional variations suggest the influence of coupled substitution mechanisms involving steacyite, a Na-dominant analogue of turkestanite, iraqite, a REE-bearing end-member in the ekanite–steacyite group, ekanite and some theoretical end-members. Turkestanite crystals were interpreted as having precipitated during post-magmatic stages in the presence of residual HFSE-rich fluidscarrying Ca, the circulation of which wasenhanced by deformational events.

Trace element distribution in mineral inclusions in zoned garnets from eclogites of the Atbashi Range (South Tianshan)

2014 ◽  
Vol 52 (11) ◽  
pp. 939-961 ◽  
Author(s):  
N. I. Volkova ◽  
S. V. Kovyazin ◽  
S. I. Stupakov ◽  
V. A. Simonov ◽  
K. S. Sakiev
Keyword(s):  
Trace Element ◽  
Element Distribution ◽  
Trace Element Distribution ◽  
Mineral Inclusions ◽  
South Tianshan

Historical trace element distribution in sediments from the Mississippi River delta

2006 ◽  
Vol 29 (6) ◽  
pp. 1094-1107 ◽  
Author(s):  
Peter W. Swarzenski ◽  
Mark Baskaran ◽  
Robert J. Rosenbauer ◽  
William H. Orem
Keyword(s):  
Trace Element ◽  
Mississippi River ◽  
Element Distribution ◽  
River Delta ◽  
Trace Element Distribution ◽  
Mississippi River Delta
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