Готові списки джерел за темами / Trace element chemistry

Добірка наукової літератури з теми "Trace element chemistry"

Автор: Grafiati
Опубліковано: 10 грудня 2022
Оновлено: 28 січня 2023

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Статті в журналах з теми "Trace element chemistry"

1

Feneyrol, Julien, Gaston Giuliani, Daniel Ohnenstetter, Benjamin Rondeau, Emmanuel Fritsch, Anthony E. Fallick, Daniel Ichang'i, et al. "New typology and origin of tsavorite based on trace-element chemistry." European Journal of Mineralogy 26, no. 2 (April 11, 2014): 293–308. http://dx.doi.org/10.1127/0935-1221/2014/0026-2367.

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2

Wong, Gifford J., Robert L. Hawley, Eric R. Lutz, and Erich C. Osterberg. "Trace-element and physical response to melt percolation in Summit (Greenland) snow." Annals of Glaciology 54, no. 63 (2013): 52–62. http://dx.doi.org/10.3189/2013aog63a602.

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AbstractSurface melt on a glacier can perturb the glaciochemical record beyond the natural variability. While the centre of the Greenland ice sheet is usually devoid of surface melt, many high-Arctic and alpine ice cores document frequent summertime melt events. Current hypotheses interpreting melt-affected ice-core chemistry rely on preferential elution of certain major ions. However, the precise nature of chemistry alteration is unknown because it is difficult to distinguish natural variability from melt effects in a perennially melt-affected site. We use eight trace-element snow chemistry records recovered from Summit, Greenland, to study spatial variability and melt effects on insoluble trace chemistry and physical stratigraphy due to artificially introduced meltwater. Differences between non-melt and melt-affected chemistry were significantly greater than the spatial variability in chemistry represented by nearest-neighbour pairs. Melt-perturbed trace elements, particularly rare earth elements, retained their seasonal stratigraphies, suggesting that trace elements may serve as robust chemical indicators for annual layers even in melt-affected study areas. Results suggest trace-element transport via meltwater percolation will deposit eluted material down-pit in refrozen areas below the nearest-surface chemistry peak. In our experiments, snow chemistry analyses are more sensitive to melt perturbations than density changes or unprocessed near-infrared digital imagery.
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3

Caporuscio, Florie A., and Joseph R. Smyth. "Trace element crystal chemistry of mantle eclogites." Contributions to Mineralogy and Petrology 105, no. 5 (October 1990): 550–61. http://dx.doi.org/10.1007/bf00302494.

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4

Baker, A. R., W. M. Landing, E. Bucciarelli, M. Cheize, S. Fietz, C. T. Hayes, D. Kadko, et al. "Trace element and isotope deposition across the air–sea interface: progress and research needs." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, no. 2081 (November 28, 2016): 20160190. http://dx.doi.org/10.1098/rsta.2016.0190.

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The importance of the atmospheric deposition of biologically essential trace elements, especially iron, is widely recognized, as are the difficulties of accurately quantifying the rates of trace element wet and dry deposition and their fractional solubility. This paper summarizes some of the recent progress in this field, particularly that driven by the GEOTRACES, and other, international research programmes. The utility and limitations of models used to estimate atmospheric deposition flux, for example, from the surface ocean distribution of tracers such as dissolved aluminium, are discussed and a relatively new technique for quantifying atmospheric deposition using the short-lived radionuclide beryllium-7 is highlighted. It is proposed that this field will advance more rapidly by using a multi-tracer approach, and that aerosol deposition models should be ground-truthed against observed aerosol concentration data. It is also important to improve our understanding of the mechanisms and rates that control the fractional solubility of these tracers. Aerosol provenance and chemistry (humidity, acidity and organic ligand characteristics) play important roles in governing tracer solubility. Many of these factors are likely to be influenced by changes in atmospheric composition in the future. Intercalibration exercises for aerosol chemistry and fractional solubility are an essential component of the GEOTRACES programme. This article is part of the themed issue ‘Biological and climatic impacts of ocean trace element chemistry’.
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5

Pavlovic, Dragana, Marija Pavlovic, Milica Markovic, Branko Karadzic, Olga Kostic, Snezana Jaric, Miroslava Mitrovic, Ivan Grzetic, and Pavle Pavlovic. "Possibilities of assessing trace metal pollution using Betula pendula Roth. leaf and bark - experience in Serbia." Journal of the Serbian Chemical Society 82, no. 6 (2017): 723–37. http://dx.doi.org/10.2298/jsc170113024p.

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In this study, both seasonal and spatial variations in trace metal uptake, as well as concentration of photosynthetic pigments in Silver birch (Betula pendula Roth.) trees in five urban parks in Pancevo, Smederevo, Obrenovac and Belgrade (Serbia) affected by different anthropogenic activities were studied. The characteristics of soil were assessed in terms of texture, pH and trace element content. Concentrations of boron, strontium and zinc in both leaves and bark showed an increasing temporal trend, however, copper showed an opposite seasonal trend. A higher accumulation of trace elements was noticed in leaves compared to bark. The obtained results for photosynthetic pigments showed low sensitivity of birch to B, Cu, Sr and Zn contamination, indicating that birch tolerates pollution and climate stress by increasing the amount of pigments. Analysis of the effects on soil chemistry of trace element accumulation in plant tissues proved that soil chemistry poorly explains the variability of elements in bark (27.6 %) compared to leaves (82.99 %). Discriminant analysis showed that Belgrade and Smederevo are clearly separated from the other three sites.
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6

Lodders, Katharina, and Bruce Fegley. "Condensation Chemistry of Circumstellar Grains." Symposium - International Astronomical Union 191 (1999): 279–90. http://dx.doi.org/10.1017/s0074180900203185.

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Thermochemical equilibrium calculations are successful in predicting the mineralogy as well as the major and trace element chemistry of circumstellar grains found in meteorites. The calculations also explain observations of dust close to AGB stars (within 1–3 stellar radii). The trace element chemistry in circumstellar graphite, SiC, and other refractory carbide grains agrees with equilibrium condensation calculations for circumstellar shells of carbon stars. Observed trace element abundance patterns in N stars are complementary to those found in SiC grains indicating fractional condensation in circumstellar shells. Condensation temperatures depend upon total pressure, C/O ratio, nitrogen abundances, and overall metallicity. Therefore for condensation temperatures to be meaningful, the total pressure and elemental abundances (i.e., C/O ratio, metallicity) must be specified.
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7

Wise, M. A. "Trace element chemistry of lithium-rich micas from rare-element granitic pegmatites." Mineralogy and Petrology 55, no. 1-3 (1995): 203–15. http://dx.doi.org/10.1007/bf01162588.

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8

Zinkutė, Rimantė, Ričardas Taraškevičius, and Tomas Želvys. "Major elements as possible factors of trace element urban pedochemical anomalies." Open Chemistry 9, no. 2 (April 1, 2011): 337–47. http://dx.doi.org/10.2478/s11532-011-0012-z.

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AbstractThe relationship between real total contents of the major elements Na, Mg, Al, Si, P, S, K, Ca, Ti, Fe and the trace elements Ag, As, B, Ba, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Sn, V, U, Zn in topsoil from the central part of Vilnius is analysed. The amounts of most elements were determined by energy-dispersive X-ray fluorescence, while amounts of Ag, B, Co were measured by optical atomic emission spectrophotometry. Two factors were distinguished according to major elements: anthropogenic (A) including Ca, Mg, Fe, P, S and clayey (C) including K, Al, Ti. Boron, Mn, Cr and U are significantly correlated with members of both factors, Sb with none of them and other trace elements either with all (Cu, Zn, Pb, Se, Ba, Ni, Co) or with separate (V, Ag, Sn, Mo, As) members of the A-factor. Only B, Mn, Cr, U (partly their additive index Z1) are influenced by the C-factor, while twelve other trace elements (also their additive index Z2) are influenced by the A-factor. The additive index Z of all 17 elements is also affected by the A-factor. Four groups of sites have been distinguished according to normal or higher contents of both factors. The majority of trace element anomalies are related to the sites affected by the A-factor.
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9

Sell, Bryan Keith, and Scott Douglas Samson. "A tephrochronologic method based on apatite trace-element chemistry." Quaternary Research 76, no. 1 (July 2011): 157–66. http://dx.doi.org/10.1016/j.yqres.2011.03.007.

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AbstractGeochemical correlation of ash-fall beds with conventional tephrochronologic methods is not feasible when original glass composition is altered. Thus, alternative correlation methods may be required. Initial studies of heavily altered Paleozoic tephra (K-bentonites) have suggested the potential for employing trace-element concentrations in apatite as ash-fall bed discriminators. To further test the utility of apatite trace-element tephrochronology, we analyzed apatite phenocrysts from unaltered volcanic rocks with an electron microprobe: nine samples from rocks erupted during the Quaternary and one sample from a rock erupted during the Paleogene. The resulting apatite trace-element data provide unique bed discriminators despite within-crystal variability. Each of the volcanic rocks studied possesses unique trends in Mg, Cl, Mn, Fe, Ce and Y concentrations in apatite. The results from this study establish an important tephrochronologic method that can be applied to nearly all portions of the Phanerozoic stratigraphic record and greatly assist development of an advanced timescale. In addition to establishing a fingerprint for a particular eruption, apatite chemistry provides useful information about the source magma.
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Davis, Catherine V., Jennifer S. Fehrenbacher, Claudia Benitez-Nelson, and Robert C. Thunell. "Trace Element Heterogeneity Across Individual Planktic Foraminifera from the Modern Cariaco Basin." Journal of Foraminiferal Research 50, no. 2 (April 1, 2020): 204–18. http://dx.doi.org/10.2113/gsjfr.50.2.204.

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ABSTRACT The trace element composition of planktic foraminifera shells is influenced by both environmental and biological factors (‘vital effects’). As trace elements in individual foraminifera shells are increasingly used as paleoceanographic tools, understanding how trace element ratios vary between individuals, among species, and in response to high frequency environmental variability is of critical importance. Here, we present a three-year plankton tow record (2010–2012) of individual shell trace element (Mg, Sr, Ba, and Mn) to Ca ratios in the planktic species Globigerina ruber (pink), Orbulina universa, and Globorotalia menardii collected throughout the upper 100 m of Cariaco Basin. Plankton tows were paired with in situ measurements of water column chemistry and hydrography. The Mg/Ca ratio reflects different calcification temperatures in all three species when calculated using species-specific temperature relationships from single-species averages of Mg/Ca. However, individual shell Mg/Ca often results in unrealistic temperate estimates. The Sr/Ca ratios are relatively constant among the four species. Ratios of Mn/Ca and Ba/Ca are highest in G. menardii and are not reflective of elemental concentrations in open waters. The Mn/Ca ratio is elevated in all species during upwelling conditions, and a similar trend is demonstrated in Neogloboquadrina incompta shells from the California margin collected during upwelling periods. Together this suggests that elevated shell Mn/Ca may act as a tracer for upwelling of deeper water masses. Our results emphasize the large degree of trace element variability present among and within species living within a limited depth habitat and the roles of biology, calcification environment, and physical mixing in mediating how trace element geochemistry reflects environmental variability in the surface ocean.
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Більше джерел

Дисертації з теми "Trace element chemistry"

1

Beere, Hugh Graham. "Study of trace element determination by ion chromatography with chemiluminescence detection." Thesis, University of Plymouth, 1995. http://hdl.handle.net/10026.1/1874.

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This thesis details the development of several highly sensitive liquid chromatography post-column reaction detectors based on chemiluminescence (CL) for the ion chromatography (IC) determination of metal species in a range of sample types. The first chapter describes a non-selective multi-element CL detector based on metal-ligand reactions involving cobalt (11) and EDTA. A complexation reaction was designed so that eluting metal species displaced or produced equivalent amount of free cobalt ions which then catalysed the CL oxidation of luminol. The effect of pH, temperature and reaction time was investigated and optimised. It was found that the detector responded to a wide range of metals capable of forming EDTA complexes, even the relatively weak complexes such as those of magnesium and calcium. However, problems with the high back-ground signal limited sensitivity to the low ug 1-1 range. The next chapter deals with the development of a highly sensitive IC method for the determination of two environmentally important chromium species, namely chromium (III) and chromium (VI). A rapid ion exchange separation was achieved using a single column with potassium chloride eluent. This was incorporated into a luminol-H2O2 CL detector, specific for chromium (III). On-line reduction was required in order to visualise the chromium (VI). Detection limits for chromium (III) and chromium (VI) wer 0.05 ug 1-1 and 0.1 /ug 1-1 respectively. Good results were obtained with a freshwater standard reference material and lyophilised samples as part of the author’s participation in a Bureau Communtaire de reference (BCR) certification exercise. Sample pH was found to have considerable influence on the stability of the species and this is described and discussed. The third and largest part of the study involved the development of an IC system for the ultra-trace determination of silver in pressurised water reactor (PWR) primary coolant, of particular concern to the nuclear power industry. A novel ion exchange separation was achieved on hydrophillic resins giving excellent separation from divalent cations. A CL post column reaction detector was designed based on the oxidation of luminol with persulphate. Good quantitative performance was accomplished based on the analysis of a certified reference material and simulated PWR coolant with detection limit for silver of 0.05 /ug 1-1. Finally, a CL detection system was developed for determining gold (III) after IC separation. A novel aspect was that no added co-oxidant was required for the luminol reaction. Results for a standard reference metal alloy sample was in good agreement with the certified value. Again, high sensitivity was achieved with a detection limit of 0.25 ug 1-1.
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2

Eisenhauer, Gary Bernard. "Trace-element chemistry of Quarternary ostracods as a palaeosalinity indicator in marginal marine environments." Thesis, Kingston University, 1999. http://eprints.kingston.ac.uk/20628/.

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The aim of this project is to evaluate the use of shell chemistry as a salinity indicator in marginal marine environments through the analysis of the elements Mg and Sr, although the significance of Mn and Fe concentrations are also assessed, within the ostracod valve and calculation of subsequent trace-element/Ca ratios. Two contrasting approaches were investigated; a modern environment where the salinity gradient is well established, and supported by previous work and field measurements (The Fleet, Dorset) and a Holocene sediment sequence where salinity was inferred from faunal palaeoecology of foraminifera and ostracods (Core SB1, Son Bou, Menorca). The species Cytherois fischeri, Leptocythere castanea, Leptocythere lacertosa, Loxoconcha rhomboidea and Xestoleberis nitida were analysed from the Fleet and generally show no relation to the host water chemistry and high variability at each study site, reflecting the tidal nature of the waterbody. However, L. lacertosa does show a weak negative trend in Mg/Ca across the transect, similar to the inverse relationships reported in a few previous studies (Teeter & Quick, 1990; Keyser et al., 1993 and Boomer, pers. comm.). Positive correlations between Sr/Ca ratios and nominal shell weight for all five species, suggests that part of the Sr content within the valve is simply related to the weight of the shell (i.e. the heavier the valve the more Sr within) and was not subsequently taken up in equilibrium with the host water. The species Cyprideis torosa and Loxoconcha elliptica were analysed from core SB1. The C. torosa Sr/Ca ratio correlated very strongly with the faunal and floral records, reflecting the environmental changes and salinity variations suggested along with the presence/absence of marine connections. The L. elliptica Sr/Ca record and Mg/Ca records for both species do not display such distinct correlations, although more subtle shifts involving increased variability do correlate with more unstable episodes and overall trends in the mean also correlate to hypothesised long term salinity trends. Positive correlation between L. elliptica Sr/Ca and nominal shell weight indicates that part of the Sr within the valve is simply related to the weight of the shell, thereby making the environmental evidence available from the L. elliptica chemistry record more limited than that of the C. torosa record. Therefore, despite the fact that the Fleet has a reduced tidal flow compared to a normal estuary, it would appear that the water chemistry is still too variable for the ostracod shell chemistry technique to be used as a reliable indicator of water chemistry, although the technique can be of limited use where corroborative evidence from other sources is necessary to support any conclusions.
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3

Muskara, Uftade. "Provenance Studies On Limestone Archaeological Artifacts Using Trace Element Analysis." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608429/index.pdf.

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Trace element composition of archaeological artifacts is commonly used for provenance studies. Limestone has generally studied by geologists and there are a few researches done by various archaeological sciences. Although it is a common material for buildings and sculpture it is been thought that limestone used had not imported like marbles. Limestone figurines from Datç
a/Emecik excavations are classified as Cypriote type, which was very popular through 6th century B.C. in the Mediterranean region. Since this type of figurines was found at Emecik numerously to determine its provenance was an important problem. Emecik figurines were examined for their some major, trace elements and REE compositions and results were compared with geological samples which were taken from a near by quarry. Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES), Inductively Coupled Plasma-Mass Spectrometry (ICPMS) have been used for analysis. The methods have been optimized by using standard reference material NIST 1d, NCS DC 73306, and IGS40.
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4

Dalbeck, Paul C. "Crystallography, stable isotope and trace element analysis of Mytilus edulis shells in the context of ontogeny." Thesis, University of Glasgow, 2008. http://theses.gla.ac.uk/1870/.

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Living systems exert exquisite control over biomineral production determining mineral type, polymorph, morphology and ultrastructure and ultimately producing biomineral structures that perform a range of functions. In addition to this biological control, the environment also influences aspects of biomineralisation. In marine invertebrates, biominerals record seawater chemistry and temperature at deposition. Past chemistry and temperature information is interpreted via proxies such as oxygen isotope and Mg/Ca ratios in calcium carbonate biominerals and used to help predict future climatic trends. Proxies must be robust and accurate yet the presence of biological or biologically-induced kinetic effects, many of which are a consequence of ontogeny, can make it difficult to isolate the environmental signal. In many cases, proxies are applied without detailed knowledge or assessment of shell microstructures and how this is altered as the animal ages. Interpretation of detailed crystallographic, chemical and isotopic changes in the context of ontogeny is therefore essential. This study considers crystallography, trace element chemistry and stable isotopic composition of six ontogenetic stages of farmed Mytilus edulis collected from a single location at the same time. The shell of Mytilus edulis is comprised of two calcium carbonate polymorphs: an outer layer of prismatic calcite and an inner layer of nacreous aragonite, both with very different morphologies. The crystallographic ultrastructure is analysed through Electron Backscatter Diffraction (EBSD) and Scanning Electron Microscopy (SEM). No significant changes in crystallography are evident between ontogenetic stages. Crystallographic orientation of calcite is more strictly constrained towards the polymorph interface and from anterior to posterior in all stages of ontogeny. Further evidence of ‘mineral bridging’ is observed in nacre. The minor element distribution varies between the polymorphs, through the shell thickness and between ontogenetic stages. Younger specimens have higher Mg, S and Sr concentrations while older specimens have increasing Na concentrations. Mg and S are present in the calcite layer but are virtually absent in aragonite. While Na and Sr occur in both polymorphs, higher concentrations occur in aragonite. Changes in Na and Sr concentrations in the aragonite layer can be linked to prismatic bands of myostracal aragonite in the nacre. A decrease in Na concentration through the calcite layer toward the polymorph interface is observed in all specimens. Increases in Mg and S concentration in the calcite layer near the interface are often observed. Greater trace element concentrations are also observed in the umbo region of the shell. Stable oxygen isotope signatures show small amounts of variation between regions of the shell and between ontogenetic stages. Decreasing δ18O values are observed in older animals and in the posterior edge of the shell. Large variations of δ18O are also observed through the shell thickness which cannot be accounted for by environmental changes. The majority of δ18O data falls within the expected range for equilibrium of calcite and aragonite with ambient seawater. No significant change is observed in δ13C values between ontogenetic stages or through the shell. Values of δ13C and δ18O co-vary in aragonite but not calcite. Refinement in crystallography occurs in conjunction with changes in trace element chemistry and stable oxygen isotope composition moving towards the shell posterior. This indicates a change as the animal grows, resulting in differences in chemical information retained in different parts of the shell. The differences in trace element chemistry between polymorphs and isotopic and chemistry changes across the shell thickness indicate changes that can be attributed to ultrastructure as crystal habit, polymorph and orientation change occur across the shell thickness. These results suggest that greater understanding of factors involved in biomineralising systems is required before undertaking work involving application of climate proxies.
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5

Smith, Kurt Thomas. "Evaluation of fin ray and fin spine chemistry as indicators of environmental history for five fish species." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/261.

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Knowledge of environmental history is important for the management and conservation of fish populations. Multiple methods to tag or mark fish have been developed (e.g., radio transmitters, coded wire tags, PIT tags, genetic markers), however, each of these methods has limitations. Naturally occurring and artificial chemical markers in otoliths have recently been used to determine natal origins and environmental history of fishes in both marine and freshwater environments and are not subject to the shortcomings of conventional tagging methods. However, few studies have evaluated the application of fish fin rays as a non-lethal alternative to fish otoliths as a recorder of individual fish environmental history. Therefore, I evaluated the application of artificial and naturally occurring chemical markers in fish fin rays as tracers of individual environmental histories. Specifically, I sought to determine 1) if age-0 lake sturgeon pectoral fin rays could be marked by immersion in strontium carbonate (SrCO3) enriched with the stable isotope 86Sr (86SrCO3), 2) whether natural differences in otolith and fin spine chemistry are present in catfish species collected from the Mississippi River basin, and 3) whether natural differences in fin ray chemistry are present in smallmouth bass from different rivers and streams in northern Illinois. Results from the first objective indicated that age-0 lake sturgeon were marked with 83% success when reared in water enriched with 100 µg/L of 86SrCO3, compared to control fish, and mark retention was maintained for at least 120 d following the labeling period. Results of the second objective indicated that both catfish otolith Sr:Ca, δ18O, and δ13C and fin spine Sr:Ca differed among sites, reflecting geographic differences in water chemistry at source locations. Both structures classified fish to their environment of capture with a high degree of accuracy, except in the Middle and Lower Mississippi Rivers where many recent immigrants appeared to be present. Similarly, smallmouth bass fin ray core Sr:Ca differed among sites, reflecting previously documented differences in water chemistry among streams and rivers in northern Illinois. Classification accuracy of smallmouth bass to their environment of capture based on fin ray Sr:Ca was variable, as some rivers had similar water chemistry signatures. The use of artificial chemical marks in fin rays will be useful when marking small fish that may not respond well to physical tags, when non-lethal recovery is desirable, and to distinguish between multiple batches of stocked fish (i.e. to evaluate factors such as stocking location and timing, fish size, and when fish may become interspersed into the existing population). Natural chemical signatures in pectoral fin rays or fin spines may provide a non-lethal alternative to otoliths for gathering information on environmental history (e.g. stock mixing, recruitment sources) of smallmouth bass and catfishes, consistent with recent demonstrations of this technique's effectiveness in other fish species. Ultimately, the use of artificial and naturally occurring chemical marks in fish fin rays provides a non-lethal alternative method to evaluate the environmental history of all life stages of fish
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6

Johansson, Linn. "Trace Element Levels in Scalp Hair from Adolescents in Río Negro, Argentina : Link to Environmental and Dietary Factors." Thesis, Linnéuniversitetet, Institutionen för naturvetenskap, NV, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-16048.

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This study provides an insight into a provincial region of a developing country, namely Río Negro, Argentina and possible links between diet, environmental factors (especially water quality) and human health. Measuring levels of trace elements in scalp hair is a known method for assessing nutritional status. Levels of Ca, Fe, Mg, K, Na, As, Cr, Co, Cu, I, Mn, Mo, Ni, Se, V, Zn, Al, Cd, Pb, Rb and Hg in scalp hair from adolescents of the age 14 to 18 years in a rural and an urban population of Río Negro were analysed by inductively coupled plasma mass spectroscopy (ICP-MS). The hypothesis is that levels of trace elements reflect lifestyle factors such as smoking, beverage and food selection and consumption patterns and are directly linked to dehydration and could be associated with future health problems. Furthermore, environmental factors, such as (i) indecent water systems and governmental subsidised food in the rural/urban population, and (ii) ingestion or inhalation of arsenic (from naturally high sources of water, dust and foodstuffs) may also be linked to present and future health problems. The relationship between environmental and dietary factors could be implicated with the onset of diseases such as diabetes type II, obesity or hypothyroidism. The results show that both study populations in the region are exposed to several trace elements in exceedingly high amounts such as As and Mn through tap water which may induce cancers. Also, regular soft drink consumption is associated with low Cr level in this population. Evidence was not obtained for assessing potential dehydration. In terms of understanding the relationship between these factors, methods for assessing dehydration and dietary consumption need to be perfected, and other demographic issues and methods for quantifying obesity and health status will require further research.
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7

Emproto, Christopher Robert. "Column Anion and Trace Element Chemistry of Apatite from Crustal Carbontite Deposits in the Grenville Province: Implications for Crustal Carbontite Genesi." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami1596134287925232.

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Brisbin, Judith Ann. "EXTRACTION TECHNIQUES FOR TRACE ELEMENT DETERMINATIONS OF BIOLOGICAL AND ENVIRONMENTAL SAMPLES INCLUDING ELEMENTAL SPECIATION OF LOBSTER USING INDUCTIVELY COUPLED PLASMA - MASS SPECTROMETRY." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin998412111.

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9

Bergbower, Joshua N. "Trace and Rare Earth Element Chemistry of Fluorite from the Illinois-Kentucky Fluorspar District and its Implications for the Origins of Mineralizing Fluids." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1530269153862162.

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10

Palacios-Fest, Manuel Roberto. "Trace element shell chemistry of continental ostracodes and the applicability of experimentally-derived multiple regression models to paleoenvironmental reconstructions in southwestern North America." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186915.

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Lacustrine ostracodes have been studied during the last three decades because of their apparent utility in reconstructing aquatic paleoenvironments. These microcrustaceans are ideal for paleoenvironmental analysis because: (1) they are cosmopolitan and abundant lacustrine inhabitants; (2) they show high diversity; (3) they are sensitive to climate-related limnological variations; (4) their valves incorporate some trace elements from host waters that may provide information on paleolimnologic conditions; and (5) their valve calcification appears to be in oxygen stable isotopic equilibrium with the host water. I designed a two-part research project to understand the significance of ostracode shell chemistry in response to the environment. First, an experiment to determine the Mg²⁺and Sr²⁺ partition coefficients (K(p)) for Limnocythere staplini, a widely distributed species in North America was executed to establish its applicability to the geologic record. Three hundred specimens of this species were individually cultured in 20 ml capped vials at discrete temperatures (15, 20 and 25 °C) and conductivities (10, 15, 20, 25, 30 μMohs/cm). After the ostracodes molted, the carapaces were removed for Ca²⁺, Mg²⁺, and Sr²⁺ analysis by inductively coupled plasma mass spectrometry (ICP-MS). Ostracode shell chemistry shows that ᵐ(Mg/Ca)(valve} is temperature dependent but not related to ᵐ(Mg²⁺/Ca²⁺)(water}. ᵐ(Sr/Ca)(valve} is dependent on TDS and possibly to ᵐ(Sr²⁺/Ca²⁺)(water}. Experimental results are applicable to a limited number of water bodies within the ranges of these analyses. Second, the equations generated in these experiments were used in a case study from the geologic record to test the applicability of this technique. Las Acequias Hohokam irrigation system provided the material for the first attempt to use ostracode shell chemistry to reconstruct the history of canal operation during Hohokam occupation (8th-15th Century A.D.). One hundred and twenty nine valves of Limnocythere staplini were analyzed by ICP-MS. I studied these valve data and associated information to determine the human water usage patterns and impact on the environment by ancient Native Americans. Current results suggest that experimental ᵐ(Mg/Ca)(valve} ratios may be used as a paleothermometer to reconstruct aquatic paleoenvironments. ᵐ(Sr/Ca)(valve} may prove to be a reliable source for reconstructing paleosalinity. The combined trace element analyses provides a powerful tool for understanding both paleoclimatic and human impact changes. However, paleoenvironmental reconstructions through partition coefficients is not warranted because thermodynamic equilibrium may not exist between water and Limnocythere staplini.
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Книги з теми "Trace element chemistry"

1

Horowitz, Arthur J. A primer on sediment-trace element chemistry. 2nd ed. [Doraville, GA]: U.S. Geological Survey, 1991.

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Horowitz, Arthur J. A primer on sediment-trace element chemistry. 2nd ed. [Doraville, GA]: U.S. Geological Survey, 1991.

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Horowitz, Arthur J. A primer on sediment-trace element chemistry. 2nd ed. [Doraville, GA]: U.S. Geological Survey, 1991.

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J, Horowitz Arthur, ed. A primer on sediment-trace element chemistry. 2nd ed. Chelsea, Mich: Lewis Publishers, 1991.

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5

L, Ebdon, and Royal Society of Chemistry (Great Britain), eds. Trace element speciation for environment, food, and health. Cambridge, UK: Royal Society of Chemistry, 2001.

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6

Yavuz, Ataman O., ed. Trace element analysis of food and diet. Cambridge, UK: RSC Pub., 2006.

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7

S, Subramanian K., and Woittiez J. R. W, eds. Element analysis of biological samples: Principles and practice. Boca Raton: CRC Press, 1998.

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8

Kuzʹmin, Vitaliĭ Andrii︠a︡novich. Geokhimii︠a︡ pochv i︠u︡ga Vostochnoĭ Sibiri. Irkutsk: Izd-vo In-ta geografii SO RAN, 2005.

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9

Woods, Paul F. Nutrient and trace-element enrichment of Coeur d'Alene Lake, Idaho. Boise, Idaho: U.S. Dept. of the Interior, U.S. Geological Survey, 1996.

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Woods, Paul F. Nutrient and trace-element enrichment of Coeur d'Alene Lake, Idaho. Boise, Idaho: U.S. Dept. of the Interior, U.S. Geological Survey, 1996.

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Частини книг з теми "Trace element chemistry"

1

McWeeny, D. J., H. M. Crews, and R. C. Massey. "Speciation Chemistry of Foods." In Biological Trace Element Research, 248–56. Washington, DC: American Chemical Society, 1991. http://dx.doi.org/10.1021/bk-1991-0445.ch019.

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Savory, J., M. G. Savory, and M. R. Wills. "Trace Metal Analysis and Quality Assurance in Clinical Chemistry." In Biological Trace Element Research, 113–19. Washington, DC: American Chemical Society, 1991. http://dx.doi.org/10.1021/bk-1991-0445.ch009.

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3

Honeyman, Bruce D. "Surface Chemistry, Colloids and Trace-Element Scavenging." In Marine Particles: Analysis and Characterization, 437–51. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm063p0437.

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4

Foust, Richard D., J. Richard Ambler, and Larry D. Turner. "Trace Element Analysis of Pueblo II Kayenta Anasazi Sherds." In Advances in Chemistry, 125–43. Washington, DC: American Chemical Society, 1989. http://dx.doi.org/10.1021/ba-1988-0220.ch007.

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5

Hope-Simpson, M., and W. Richards. "Practical and Regulatory Challenges in Controlling Trace Element Inputs to Soils from Land Application of Fluidized Bed Combustion Residues." In Chemistry of Trace Elements in Fly Ash, 63–74. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/978-1-4757-4757-7_5.

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6

Stalder, Marcel, and Abraham Rozendaal. "Trace and rare earth element chemistry of garnet and apatite as discriminant for Broken Hill-Type mineralization, Namaqua Province, South Africa." In Mineral Deposit Research: Meeting the Global Challenge, 699–702. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/3-540-27946-6_178.

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7

Tack, Filip M. G. "Trace Elements: General Soil Chemistry, Principles and Processes." In Trace Elements in Soils, 9–37. Chichester, UK: John Wiley & Sons, Ltd, 2010. http://dx.doi.org/10.1002/9781444319477.ch2.

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8

Suzuki, Nobuo. "Radiometric determination of trace elements." In Topics in Current Chemistry, 35–55. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/3-540-52423-1_2.

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9

Gaubert, S., L. Lambs, and G. Berthon. "Copper-Histidine and -NSAID Complexes in Fenton Chemistry." In Therapeutic Uses of Trace Elements, 139–44. Boston, MA: Springer US, 1996. http://dx.doi.org/10.1007/978-1-4899-0167-5_21.

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10

Savory, J., and M. R. Wills. "Biological Monitoring of Exposure to Toxic Trace Elements." In Clinical Chemistry, 83–92. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4613-0753-2_9.

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Тези доповідей конференцій з теми "Trace element chemistry"

1

Beaudoin, Casey, and G. Nelson Eby. "TRACE ELEMENT CHEMISTRY OF EMERALDS." In 53rd Annual GSA Northeastern Section Meeting - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018ne-310734.

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2

Harkness, Jennifer S., and Thomas H. Darrah. "TRACE METAL AND RARE EARTH ELEMENT CHEMISTRY OF MODERN HUMAN BONE." In GSA Annual Meeting in Indianapolis, Indiana, USA - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018am-321810.

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3

Scibiorski, Elisabeth, and Peter Cawood. "The trace element chemistry of titanite varies with host rock lithology." In Goldschmidt2021. France: European Association of Geochemistry, 2021. http://dx.doi.org/10.7185/gold2021.6536.

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4

Barbato, Allison Kay, Barbara L. Dutrow, and Darrell J. Henry. "CATHODOLUMINESCENCE AND TRACE ELEMENT CHEMISTRY OF SILLIMANITE: EVIDENCE FOR MULTIPLE METAMORPHIC REACTIONS." In GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-299153.

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Stearn, Madelaine. "GEOCHEMICAL ANALYSIS OF LASCAR VOLCANO: DIFFUSION CHRONOMETRY, MINERAL CHEMISTRY, AND TRACE ELEMENT CHEMISTRY OF ZIRCON AND PLAGIOCLASE." In GSA Annual Meeting in Phoenix, Arizona, USA - 2019. Geological Society of America, 2019. http://dx.doi.org/10.1130/abs/2019am-338090.

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6

Gale, Chesley Philip, and Jason F. Kaiser. "ASSESSING GEOTHERMAL ENERGY POTENTIAL IN SOUTHERN UTAH USING THE TRACE ELEMENT CHEMISTRY OF GRANITIC INTRUSIONS." In GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-305051.

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7

Hruska, Grace, Jade Star Lackey, and Kyle R. McCarty. "TITANITE U-PB AGE AND TRACE ELEMENT CHEMISTRY: TRACING COOLING AND ALTERATION IN SIERRA NEVADA BATHOLITH." In GSA Annual Meeting in Phoenix, Arizona, USA - 2019. Geological Society of America, 2019. http://dx.doi.org/10.1130/abs/2019am-340573.

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8

Senol, Naci Sertug, and Daniel Gregory. "Testing Pyrrhotite Trace Element Chemistry as a Vector Towards the Mineralization in the Sullivan Deposit, B.C." In Goldschmidt2022. France: European Association of Geochemistry, 2022. http://dx.doi.org/10.46427/gold2022.10285.

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9

Fulton, Anne, Elizabeth Holley, and Patrick J. Sack. "WINDOWS INTO HYDROTHERMAL FLUID CHEMISTRY VIA NANOSCALE ANALYSES OF SULFIDE TRACE ELEMENT ZONING IN CARLIN GOLD DEPOSITS." In GSA 2020 Connects Online. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020am-353968.

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10

Karvinen, S., A. Heinonen, and C. Beier. "Apatite as a tracer for magmatic-hydrothermal ore-forming processes." In Project KO5125 ARLIN Arctic Layered Intrusions as a Source of Critical Metals for Green Economy European Neighbourhood Instrument Cross-Border Cooperation Programme Kolarctic 2014-2020. GI KSC RAS, 2021. http://dx.doi.org/10.31241/arlin.2021.019.

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This project focuses on the trace element chemistry of igneous apatite in various magmatic systems with the use of in situ analytical techniques. The composition of apatite may possibly be used as a tracer for various magmatic-hydrothermal processes due to the breadth of chemical substitutions possible within the structure. Apatite is found in many mineralized layered intrusions as a minor phase. Apatite may be utilized in the tracking of metasomatic fluids in layered intrusions or in geochronological studies in the absence of other commonly used phases i.e. zircon. Apatite accumulations can be exploited economically for phosphorus and possibly for rare earth elements as well.
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Звіти організацій з теми "Trace element chemistry"

1

Olson, Angela, and Lav Tandon. Actinide Analytical Chemistry Overview ICP Trace Element Analysis (Including U, Np). Office of Scientific and Technical Information (OSTI), January 2022. http://dx.doi.org/10.2172/1840858.

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2

Birk, D., and J. C. White. Trace Elements in Bituminous Coals, Roof Clays, and Under Clays of the Sydney Basin, Nova Scotia: Ash Chemistry, Element Sites, and Mineralogy. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1990. http://dx.doi.org/10.4095/129042.

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3

Neyedley, K., J. J. Hanley, Z. Zajacz, and M. Fayek. Accessory mineral thermobarometry, trace element chemistry, and stable O isotope systematics, Mooshla Intrusive Complex (MIC), Doyon-Bousquet-LaRonde mining camp, Abitibi greenstone belt, Québec. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328986.

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The Mooshla Intrusive Complex (MIC) is an Archean polyphase magmatic body located in the Doyon-Bousquet-LaRonde (DBL) mining camp of the Abitibi greenstone belt, Québec, that is spatially associated with numerous gold (Au)-rich VMS, epizonal 'intrusion-related' Au-Cu vein systems, and shear zone-hosted (orogenic?) Au deposits. To elucidate the P-T conditions of crystallization, and oxidation state of the MIC magmas, accessory minerals (zircon, rutile, titanite) have been characterized using a variety of analytical techniques (e.g., trace element thermobarometry). The resulting trace element and oxythermobarometric database for accessory minerals in the MIC represents the first examination of such parameters in an Archean magmatic complex in a world-class mineralized district. Mineral thermobarometry yields P-T constraints on accessory mineral crystallization consistent with the expected conditions of tonalite-trondhjemite-granite (TTG) magma genesis, well above peak metamorphic conditions in the DBL camp. Together with textural observations, and mineral trace element data, the P-T estimates reassert that the studied minerals are of magmatic origin and not a product of metamorphism. Oxygen fugacity constraints indicate that while the magmas are relatively oxidizing (as indicated by the presence of magmatic epidote, titanite, and anhydrite), zircon trace element systematics indicate that the magmas were not as oxidized as arc magmas in younger (post-Archean) porphyry environments. The data presented provides first constraints on the depth and other conditions of melt generation and crystallization of the MIC. The P-T estimates and qualitative fO2 constraints have significant implications for the overall model for formation (crystallization, emplacement) of the MIC and potentially related mineral deposits.
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4

Potter, E. G., P. Acosta-Góngora, L. Corriveau, J. F. Montreuil, and Z. Yang. Uranium enrichment processes in metasomatic iron oxide and alkali-calcic systems as revealed by uraninite trace element chemistry - supplementary data. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328300.

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5

Brenan, J. M., K. Woods, J. E. Mungall, and R. Weston. Origin of chromitites in the Esker Intrusive Complex, Ring of Fire Intrusive Suite, as revealed by chromite trace element chemistry and simple crystallization models. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328981.

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To better constrain the origin of the chromitites associated with the Esker Intrusive Complex (EIC) of the Ring of Fire Intrusive Suite (RoFIS), a total of 50 chromite-bearing samples from the Black Thor, Big Daddy, Blackbird, and Black Label chromite deposits have been analysed for major and trace elements. The samples represent three textural groups, as defined by the relative abundance of cumulate silicate phases and chromite. To provide deposit-specific partition coefficients for modeling, we also report on the results of laboratory experiments to measure olivine- and chromite-melt partitioning of V and Ga, which are two elements readily detectable in the chromites analysed. Comparison of the Cr/Cr+Al and Fe/Fe+Mg of the EIC chromites and compositions from previous experimental studies indicates overlap in Cr/Cr+Al between the natural samples and experiments done at >1400oC, but significant offset of the natural samples to higher Fe/Fe+Mg. This is interpreted to be the result of subsolidus Fe-Mg exchange between chromite and the silicate matrix. However, little change in Cr/Cr+Al from magmatic values, owing to the lack of an exchangeable reservoir for these elements. A comparison of the composition of the EIC chromites and a subset of samples from other tectonic settings reveals a strong similarity to chromites from the similarly-aged Munro Township komatiites. Partition coefficients for V and Ga are consistent with past results in that both elements are compatible in chromite (DV = 2-4; DGa ~ 3), and incompatible in olivine (DV = 0.01-0.14; DGa ~ 0.02), with values for V increasing with decreasing fO2. Simple fractional crystallization models that use these partition coefficients are developed that monitor the change in element behaviour based on the relative proportions of olivine to chromite in the crystallizing assemblage; from 'normal' cotectic proportions involving predominantly olivine, to chromite-only crystallization. Comparison of models to the natural chromite V-Ga array suggests that the overall positive correlation between these two elements is consistent with chromite formed from a Munro Township-like komatiitic magma crystallizing olivine and chromite in 'normal' cotectic proportions, with no evidence of the strong depletion in these elements expected for chromite-only crystallization. The V-Ga array can be explained if the initial magma responsible for chromite formation is slightly reduced with respect to the FMQ oxygen buffer (~FMQ- 0.5), and has assimilated up to ~20% of wall-rock banded iron formation or granodiorite. Despite the evidence for contamination, results indicate that the EIC chromitites crystallized from 'normal' cotectic proportions of olivine to chromite, and therefore no specific causative link is made between contamination and chromitite formation. Instead, the development of near- monomineralic chromite layers likely involves the preferential removal of olivine relative to chromite by physical segregation during magma flow. As suggested for some other chromitite-forming systems, the specific fluid dynamic regime during magma emplacement may therefore be responsible for crystal sorting and chromite accumulation.
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6

Ames, D. E., and G. Tuba. Epidote-amphibole and accessory phase mineral chemistry as a vector to low-sulphide platinum group element mineralization, Sudbury: laser ablation ICP-MS trace element study of hydrothermal alteration. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2015. http://dx.doi.org/10.4095/296695.

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7

Kontak, D. J., A. M. McDonald, R. Poulin, J. Petrus, and M B McClenaghan. Scheelite as a possible ore-deposit discriminator based on luminescence, trace-element chemistry, delta-18O signature, fluid inclusions, and U-Pb geochronology. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2017. http://dx.doi.org/10.4095/306315.

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8

Spry, P. G., M. V. Pollock, K. A. Tott, A. E. Koenig, R A Both, and J. A. Ogierman. Trace element chemistry of indicator silicates and oxides as vectors to metamorphosed sediment-hosted Pb-Zn-Ag and Cu-Au deposits in the Cambrian Kanmantoo Group, South Australia. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2017. http://dx.doi.org/10.4095/306311.

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9

Neyedley, K., J. J. Hanley, P. Mercier-Langevin, and M. Fayek. Ore mineralogy, pyrite chemistry, and S isotope systematics of magmatic-hydrothermal Au mineralization associated with the Mooshla Intrusive Complex (MIC), Doyon-Bousquet-LaRonde mining camp, Abitibi greenstone belt, Québec. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328985.

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Анотація:
The Mooshla Intrusive Complex (MIC) is an Archean polyphase magmatic body located in the Doyon-Bousquet-LaRonde (DBL) mining camp of the Abitibi greenstone belt, Québec. The MIC is spatially associated with numerous gold (Au)-rich VMS, epizonal 'intrusion-related' Au-Cu vein systems, and shear zone-hosted (orogenic?) Au deposits. To elucidate genetic links between deposits and the MIC, mineralized samples from two of the epizonal 'intrusion-related' Au-Cu vein systems (Doyon and Grand Duc Au-Cu) have been characterized using a variety of analytical techniques. Preliminary results indicate gold (as electrum) from both deposits occurs relatively late in the systems as it is primarily observed along fractures in pyrite and gangue minerals. At Grand Duc gold appears to have formed syn- to post-crystallization relative to base metal sulphides (e.g. chalcopyrite, sphalerite, pyrrhotite), whereas base metal sulphides at Doyon are relatively rare. The accessory ore mineral assemblage at Doyon is relatively simple compared to Grand Duc, consisting of petzite (Ag3AuTe2), calaverite (AuTe2), and hessite (Ag2Te), while accessory ore minerals at Grand Duc are comprised of tellurobismuthite (Bi2Te3), volynskite (AgBiTe2), native Te, tsumoite (BiTe) or tetradymite (Bi2Te2S), altaite (PbTe), petzite, calaverite, and hessite. Pyrite trace element distribution maps from representative pyrite grains from Doyon and Grand Duc were collected and confirm petrographic observations that Au occurs relatively late. Pyrite from Doyon appears to have been initially trace-element poor, then became enriched in As, followed by the ore metal stage consisting of Au-Ag-Te-Bi-Pb-Cu enrichment and lastly a Co-Ni-Se(?) stage enrichment. Grand Duc pyrite is more complex with initial enrichments in Co-Se-As (Stage 1) followed by an increase in As-Co(?) concentrations (Stage 2). The ore metal stage (Stage 3) is indicated by another increase in As coupled with Au-Ag-Bi-Te-Sb-Pb-Ni-Cu-Zn-Sn-Cd-In enrichment. The final stage of pyrite growth (Stage 4) is represented by the same element assemblage as Stage 3 but at lower concentrations. Preliminary sulphur isotope data from Grand Duc indicates pyrite, pyrrhotite, and chalcopyrite all have similar delta-34S values (~1.5 � 1 permille) with no core-to-rim variations. Pyrite from Doyon has slightly higher delta-34S values (~2.5 � 1 permille) compared to Grand Duc but similarly does not show much core-to-rim variation. At Grand Duc, the occurrence of Au concentrating along the rim of pyrite grains and associated with an enrichment in As and other metals (Sb-Ag-Bi-Te) shares similarities with porphyry and epithermal deposits, and the overall metal association of Au with Te and Bi is a hallmark of other intrusion-related gold systems. The occurrence of the ore metal-rich rims on pyrite from Grand Duc could be related to fluid boiling which results in the destabilization of gold-bearing aqueous complexes. Pyrite from Doyon does not show this inferred boiling texture but shares characteristics of dissolution-reprecipitation processes, where metals in the pyrite lattice are dissolved and then reconcentrated into discrete mineral phases that commonly precipitate in voids and fractures created during pyrite dissolution.
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10

Reid, M. S., X. Wang, N. Utting, and C. Jiang. Comparison of water chemistry of hydraulic-fracturing flowback water from two geological locations at the Duvernay Formation, Alberta, Canada. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/329276.

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We analyzed and compared the water chemistry between 17 Fox Creek region samples, each from a different well, and 23 Three Hills region samples from a single well. Overall, the two regions were similar in chemical composition but showed small differences in some lower abundance dissolved elements. Additionally, we investigated changes in water chemistry of FPW over time from a single well. The majority of water quality parameters and water chemistry remained constant over the 7-month sampling time. Major ion chemistry showed increasing concentrations of Ca and Mg, and a decreasing concentration of SO4. Several trace elements also showed small trends of both increasing and decreasing concentrations over time. There was a strong correlation between Ca and Mg concentrations in both the Fox Creek region samples and Three Hills region samples, which is an indication of the mixing of formation water. However, the correlation between B and Sr was different among two region samples, which is likely due to the delayed mixing of formation water with the fracturing fluids during the flowback at different time periods of post fracturing. Likewise, Fox Creek region samples showed correlations between concentrations of Cl and Ca, Na and Ca, and Na and Mg, but these correlations were not seen in the Three Hills region samples. Geochemical modeling demonstrates that there are potential scales formed in the flowback water, but most of the minerals are still in the dissolution state in the formation. Stable isotopic analysis confirmed the mixing of injection water and the formation water.
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