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Ingo Horn - One of the best experts on this subject based on the ideXlab platform.
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investigation on elemental and Isotopic Fractionation during 196 nm femtosecond laser ablation multiple collector inductively coupled plasma mass spectrometry
Spectrochimica Acta Part B: Atomic Spectroscopy, 2007Co-Authors: Ingo Horn, Friedhelm Von BlanckenburgAbstract:Abstract Despite the large number of successful applications of laser ablation, elemental and Isotopic Fractionation coupled to inductively coupled plasma mass spectrometry (ICP-MS) remain as the main limitations for many applications of this technique in the fields of analytical chemistry and Earth Sciences. A substantial effort has been made to control such Fractionations, which are well-established features of nanosecond laser ablation systems. Technological advancements made over the past decade now allow the ablation of solids by femtosecond laser pulses in the deep ultraviolet (UV) region at wavelengths less than 200 nm. Here the use of femtosecond laser ablation and its effects on elemental and Isotopic Fractionation is investigated. The Pb/U system is used to illustrate elemental Fractionation and stable Fe isotopes are used to illustrate Isotopic Fractionation. No elemental Fractionation is observed beyond the precision of the multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) measurements. Without a matrix match between standard and sample, elemental Fractionation is absent even when using different laser ablation protocols for standardization and samples (spot versus raster). Furthermore, we found that laser ablation-induced isotope ratio drifts, commonly observed during nanosecond laser ablation, are undetectable during ultraviolet femtosecond laser ablation. So far the precision obtained for Fe isotope ratio determinations is 0.1‰ (2 standard deviation) for the 56 Fe/ 54 Fe ratio. This is close to that obtainable by solution multiple-collector inductively coupled plasma mass spectrometry. The accuracy of the results appears to be independent of the matrix used for standardization. The resulting smaller particle sizes reduce Fractionation processes. Femtosecond laser ablation carries the potential to solve some of the difficulties encountered during the two prior decades since the introduction of laser ablation.
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Investigation on elemental and Isotopic Fractionation during 196 nm femtosecond laser ablation multiple collector inductively coupled plasma mass spectrometry
Spectrochimica Acta - Part B Atomic Spectroscopy, 2007Co-Authors: Ingo Horn, Friedhelm Von BlanckenburgAbstract:Despite the large number of successful applications of laser ablation, elemental and Isotopic Fractionation coupled to inductively coupled plasma mass spectrometry (ICP-MS) remain as the main limitations for many applications of this technique in the fields of analytical chemistry and Earth Sciences. A substantial effort has been made to control such Fractionations, which are well-established features of nanosecond laser ablation systems. Technological advancements made over the past decade now allow the ablation of solids by femtosecond laser pulses in the deep ultraviolet (UV) region at wavelengths less than 200 nm. Here the use of femtosecond laser ablation and its effects on elemental and Isotopic Fractionation is investigated. The Pb/U system is used to illustrate elemental Fractionation and stable Fe isotopes are used to illustrate Isotopic Fractionation. No elemental Fractionation is observed beyond the precision of the multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) measurements. Without a matrix match between standard and sample, elemental Fractionation is absent even when using different laser ablation protocols for standardization and samples (spot versus raster). Furthermore, we found that laser ablation-induced isotope ratio drifts, commonly observed during nanosecond laser ablation, are undetectable during ultraviolet femtosecond laser ablation. So far the precision obtained for Fe isotope ratio determinations is 0.1‰ (2 standard deviation) for the 56Fe/54Fe ratio. This is close to that obtainable by solution multiple-collector inductively coupled plasma mass spectrometry. The accuracy of the results appears to be independent of the matrix used for standardization. The resulting smaller particle sizes reduce Fractionation processes. Femtosecond laser ablation carries the potential to solve some of the difficulties encountered during the two prior decades since the introduction of laser ablation. © 2007 Elsevier B.V. All rights reserved.
Friedhelm Von Blanckenburg - One of the best experts on this subject based on the ideXlab platform.
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Investigation on elemental and Isotopic Fractionation during 196 nm femtosecond laser ablation multiple collector inductively coupled plasma mass spectrometry
Spectrochimica Acta - Part B Atomic Spectroscopy, 2007Co-Authors: Ingo Horn, Friedhelm Von BlanckenburgAbstract:Despite the large number of successful applications of laser ablation, elemental and Isotopic Fractionation coupled to inductively coupled plasma mass spectrometry (ICP-MS) remain as the main limitations for many applications of this technique in the fields of analytical chemistry and Earth Sciences. A substantial effort has been made to control such Fractionations, which are well-established features of nanosecond laser ablation systems. Technological advancements made over the past decade now allow the ablation of solids by femtosecond laser pulses in the deep ultraviolet (UV) region at wavelengths less than 200 nm. Here the use of femtosecond laser ablation and its effects on elemental and Isotopic Fractionation is investigated. The Pb/U system is used to illustrate elemental Fractionation and stable Fe isotopes are used to illustrate Isotopic Fractionation. No elemental Fractionation is observed beyond the precision of the multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) measurements. Without a matrix match between standard and sample, elemental Fractionation is absent even when using different laser ablation protocols for standardization and samples (spot versus raster). Furthermore, we found that laser ablation-induced isotope ratio drifts, commonly observed during nanosecond laser ablation, are undetectable during ultraviolet femtosecond laser ablation. So far the precision obtained for Fe isotope ratio determinations is 0.1‰ (2 standard deviation) for the 56Fe/54Fe ratio. This is close to that obtainable by solution multiple-collector inductively coupled plasma mass spectrometry. The accuracy of the results appears to be independent of the matrix used for standardization. The resulting smaller particle sizes reduce Fractionation processes. Femtosecond laser ablation carries the potential to solve some of the difficulties encountered during the two prior decades since the introduction of laser ablation. © 2007 Elsevier B.V. All rights reserved.
Friedhelm Von Blanckenburg - One of the best experts on this subject based on the ideXlab platform.
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investigation on elemental and Isotopic Fractionation during 196 nm femtosecond laser ablation multiple collector inductively coupled plasma mass spectrometry
Spectrochimica Acta Part B: Atomic Spectroscopy, 2007Co-Authors: Ingo Horn, Friedhelm Von BlanckenburgAbstract:Abstract Despite the large number of successful applications of laser ablation, elemental and Isotopic Fractionation coupled to inductively coupled plasma mass spectrometry (ICP-MS) remain as the main limitations for many applications of this technique in the fields of analytical chemistry and Earth Sciences. A substantial effort has been made to control such Fractionations, which are well-established features of nanosecond laser ablation systems. Technological advancements made over the past decade now allow the ablation of solids by femtosecond laser pulses in the deep ultraviolet (UV) region at wavelengths less than 200 nm. Here the use of femtosecond laser ablation and its effects on elemental and Isotopic Fractionation is investigated. The Pb/U system is used to illustrate elemental Fractionation and stable Fe isotopes are used to illustrate Isotopic Fractionation. No elemental Fractionation is observed beyond the precision of the multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) measurements. Without a matrix match between standard and sample, elemental Fractionation is absent even when using different laser ablation protocols for standardization and samples (spot versus raster). Furthermore, we found that laser ablation-induced isotope ratio drifts, commonly observed during nanosecond laser ablation, are undetectable during ultraviolet femtosecond laser ablation. So far the precision obtained for Fe isotope ratio determinations is 0.1‰ (2 standard deviation) for the 56 Fe/ 54 Fe ratio. This is close to that obtainable by solution multiple-collector inductively coupled plasma mass spectrometry. The accuracy of the results appears to be independent of the matrix used for standardization. The resulting smaller particle sizes reduce Fractionation processes. Femtosecond laser ablation carries the potential to solve some of the difficulties encountered during the two prior decades since the introduction of laser ablation.
Detlef Gunther - One of the best experts on this subject based on the ideXlab platform.
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the nature and sources of laser induced Isotopic Fractionation in laser ablation multicollector inductively coupled plasma mass spectrometry
Journal of Analytical Atomic Spectrometry, 2003Co-Authors: Simon E Jackson, Detlef GuntherAbstract:Coupling laser ablation sampling with MC-ICP-MS detection allows rapid, in situ determination of isotope ratios. However, measured isotope ratios can show large biases relative to the true ratio. We show that, at low laser pulse energies (3 J cm−2), the laser ablation aerosol of copper metal possessed a 65Cu/63Cu ratio that deviated by more than 12 e units (12 parts per 10,000) from that of the sample. At high pulse energies (9 J cm−2 and above), near Isotopically stoichiometric ablation generally occurred. However, even at high pulse energies, on-line laser ablation-MC-ICP-MS Cu isotope ratios showed large biases (15–48 e units) from the target sample. Filtering larger particles (>0.5 µm) from the ablation aerosol was accompanied by a reduction in signal that was generally much smaller than the associated reduction in volume transport (a factor of 2.8–84 for ablations in Ar), suggesting that volatilisation and ionisation of particles in the ICP was incomplete. Filtered aerosols always yielded Isotopic values that were closer to the true value than unfiltered aerosols by an average of 18 e units. These data suggest that, while significant Isotopic Fractionation occurred at the ablation site at low laser fluence, the dominant source of Isotopic Fractionation at high laser fluence was the preferential volatilisation of 63Cu during incomplete vaporisation and ionisation in the ICP of particles greater than approximately 0.5 µm in diameter.
Frédéric Moynier - One of the best experts on this subject based on the ideXlab platform.
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Isotopic Fractionation of zirconium during magmatic differentiation and the stable isotope composition of the silicate earth
Geochimica et Cosmochimica Acta, 2019Co-Authors: Edward C Inglis, Frédéric Moynier, Fangzhen Teng, John Creech, Zhengbin Deng, Martin Bizzarro, Matthew G Jackson, Paul S SavageAbstract:Abstract High-precision double-spike Zr stable isotope measurements (expressed as δ94/90ZrIPGP-Zr, the permil deviation of the 94Zr/90Zr ratio from the IPGP-Zr standard) are presented for a range of ocean island basalts (OIB) and mid-ocean ridge basalts (MORB) to examine mass-dependent Isotopic variations of zirconium in Earth. Ocean island basalt samples, spanning a range of radiogenic Isotopic flavours (HIMU, EM) show a limited range in δ94/90ZrIPGP-Zr (0.046 ± 0.037‰; 2sd, n = 13). Similarly, MORB samples with chondrite-normalized La/Sm of >0.7 show a limited range in δ94/90ZrIPGP-Zr (0.053 ± 0.040‰; 2sd, n = 8). In contrast, basaltic lavas from mantle sources that have undergone significant melt depletion, such as depleted normal MORB (N-MORB) show resolvable variations in δ94/90ZrIPGP-Zr, from −0.045 ± 0.018 to 0.074 ± 0.023‰. Highly evolved igneous differentiates (>65 wt% SiO2) from Hekla volcano in Iceland are Isotopically heavier than less evolved igneous rocks, up to 0.53‰. These results suggest that both mantle melt depletion and extreme magmatic differentiation leads to resolvable mass-dependent Zr isotope Fractionation. We find that this Isotopic Fractionation is most likely driven by incorporation of light isotopes of Zr within the 8-fold coordinated sites of zircons, driving residual melts, with a lower coordination chemistry, towards heavier values. Using a Rayleigh Fractionation model, we suggest a αzircon-melt of 0.9995 based on the whole rock δ94/90ZrIPGP-Zr values of the samples from Hekla volcano (Iceland). Zirconium Isotopic Fractionation during melt-depletion of the mantle is less well-constrained, but may result from incongruent melting and incorporation of Isotopically light Zr in the 8-fold coordinated M2 site of orthopyroxene. Based on these observations lavas originating from the effect of melt extraction from a depleted mantle source (N-MORB) or that underwent zircon saturation (SiO2 > 65 wt%) are removed from the dataset to give an estimate of the primitive mantle Zr isotope composition of 0.048 ± 0.032‰; 2sd, n = 48. These data show that major controls on Zr Fractionation in the Earth result from partial melt extraction in the mantle and by zircon Fractionation in differentiated melts. Conversely, fertile mantle is homogenous with respect to Zr isotopes. Zirconium mass-dependent Fractionation effects can therefore be used to trace large-scale mantle melt depletion events and the effects of felsic crust formation.
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the iron isotope composition of enstatite meteorites implications for their origin and the metal sulfide fe Isotopic Fractionation factor
Geochimica et Cosmochimica Acta, 2014Co-Authors: Frédéric Moynier, Kun Wang, Paul S SavageAbstract:Abstract Despite their unusual chemical composition, it is often proposed that the enstatite chondrites represent a significant component of Earth’s building materials, based on their terrestrial similarity for numerous isotope systems. In order to investigate a possible genetic relationship between the Fe isotope composition of enstatite chondrites and the Earth, we have analyzed 22 samples from different subgroups of the enstatite meteorites, including EH and EL chondrites, aubrites (main group and Shallowater) and the Happy Canyon impact melt. We have also analyzed the Fe Isotopic compositions of separated (magnetic and non-magnetic) phases from both enstatite chondrites and achondrites. On average, EH3–5 chondrites (δ56Fe = 0.003 ± 0.042‰; 2 standard deviation; n = 9; including previous literature data) as well as EL3 chondrites (δ56Fe = 0.030 ± 0.038‰; 2 SD; n = 2) have identical and homogeneous Fe Isotopic compositions, indistinguishable from those of the carbonaceous chondrites and average terrestrial peridotite. In contrast, EL6 chondrites display a larger range of Isotopic compositions (−0.180‰ Enstatite achondrites (aubrites) also exhibit a relatively large range of Fe isotope compositions: all main group aubrites are enriched in the light Fe isotopes (δ56Fe = −0.170 ± 0.189‰; 2 SD; n = 6), while Shallowater is, Isotopically, relatively heavy (δ56Fe = 0.045 ± 0.101‰; 2 SD; n = 4; number of chips). We take this variation to suggest that the main group aubrite parent body formed a discreet heavy Fe isotope-enriched core, whilst the Shallowater meteorite is most likely from a different parent body where core and silicate material remixed. This could be due to intensive impact-induced shearing stress, or the ultimate destruction of the Shallowater parent body. Analysis of separated enstatite meteorite mineral phases show that the magnetic phase (Fe metal) is systematically enriched in the heavier Fe isotopes when compared to non-magnetic phases (Fe hosted in troilite), which agrees with previous experimental observations and theoretical calculations. The difference between magnetic and non-magnetic phases from enstatite achondrites provides an equilibrium metal–sulfide Fe Isotopic Fractionation factor of Δ56Femetal–troilite = δ56Femetal − δ56Fetroilite of 0.129 ± 0.060‰ (2 SE) at 1060 ± 80 K, which confirms the predictions of previous theoretical calculations.
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iron zinc magnesium and uranium Isotopic Fractionation during continental crust differentiation the tale from migmatites granitoids and pegmatites
Geochimica et Cosmochimica Acta, 2012Co-Authors: M Telus, Frédéric Moynier, Nicolas Dauphas, F L H Tissot, Fangzhen Teng, Peter I Nabelek, Paul R Craddock, Lee A GroatAbstract:Abstract The causes of some stable Isotopic variations in felsic rocks are not well understood. In particular, the origin of the heavy Fe Isotopic compositions (i.e., high δ56Fe values, deviation in ‰ of the 56Fe/54Fe ratio relative to IRMM-014) of granites with SiO2 > 70 wt.% compared with less silicic rocks is still debated. It has been interpreted to reflect Isotopic Fractionation during late stage aqueous fluid exsolution, magma differentiation, partial melting, or Soret (thermal) diffusion. The present study addresses this issue by comparing the Fe Isotopic compositions of a large range of differentiated crustal rocks (whole rocks of migmatites, granitoids, and pegmatites; mineral separates) with the Isotopic compositions of Zn, Mg and U. The samples include granites, migmatites and pegmatites from the Black Hills, South Dakota (USA), as well as I-, S-, and A-type granitoids from Lachlan Fold Belt (Australia). The nature of the protolith (i.e., I- or S-type) does not influence the Fe Isotopic composition of granitoids. Leucosomes (partial melts in migmatites) tend to have higher δ56Fe values than melanosomes (melt residues) indicating that partial melting of continental crust material can possibly fractionate Fe isotopes. No clear positive correlation is found between the Isotopic compositions of Mg, U and Fe, which rules out the process of Soret diffusion in the systems studied here. Zinc isotopes were measured to trace fluid exsolution because Zn can easily be mobilized by aqueous fluids as chloride complexes. Pegmatites and some granitic rocks with high δ56Fe values also have high δ66Zn values. In addition, high-SiO2 granites show a large dispersion in the Zn/Fe ratio that cannot easily be explained by magma differentiation alone. These results suggest that fluid exsolution is responsible for some of the Fe Isotopic Fractionation documented in felsic rocks and in particular in pegmatites. However, some granites with high δ56Fe values have unfractionated δ66Zn values and were presumably poor in fluids (e.g., A-type). For these samples, iron Isotopic Fractionation during magma differentiation is a viable interpretation. Equilibrium Fe Isotopic Fractionation factors between silicic melts and minerals remain to be characterized to quantitatively assess the role of fractional crystallization on iron isotopes in granitoids.
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Isotopic Fractionation of cu in plants
Chemical Geology, 2011Co-Authors: Charlotte Weinstein, Frédéric Moynier, Kun Wang, Randal C Paniello, Julien Foriel, Jeffrey G Catalano, Sylvain PichatAbstract:Abstract Knowledge of the copper cycle in the plant–soil–water system is needed in order to better constrain proper plant micronutrient nutrition, control pollution, and determine sustainable soil management practices. Here, we report the Cu Isotopic compositions of different components (seeds, germinated seeds, leaves, and stems) of the dicot, lentil ( Lens culinaris ), and of two monocots, Virginia wild rye ( Elymus virginicus ) and hairy-leaved sedge ( Carex hirsutella) . According to our data, the Isotopic compositions of these plants are systematically enriched in the lighter isotope of Cu ( 63 Cu) in comparison to the soil in which they grow. Furthermore, different components within the plants themselves are Isotopically fractionated. The shoots (stems, leaves and seeds) are systematically lighter than the germinated seeds of the plants and the Cu Isotopic compositions of individual leaves correlate with their heights on the plant. These results are similar to what has been observed for Zn isotopes, which are assumed to be transported through plants by means of diffusion and kinetic Fractionation across cell membranes. Because of this similarity, we suggest that the same transport mechanisms are also responsible for the observed Isotopic Fractionation of Cu. As a side-note, the Cu Isotopic variations measured in plants are similar in magnitude to the differences previously measured in various soils, and therefore should not be neglected while interpreting the Isotopic composition of soils.
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Isotopic Fractionation of Cu in tektites
Geochimica et Cosmochimica Acta, 2010Co-Authors: Frédéric Moynier, Christian Koeberl, Pierre Beck, Fred Jourdan, Philippe TeloukAbstract:Tektites are terrestrial natural glasses of up to a few centimeters in size that were produced during hypervelocity impacts on the Earth's surface. It is well established that the chemical and Isotopic composition of tektites is generally identical to that of the upper terrestrial continental crust. Tektites typically have very low water content, which has generally been explained by volatilization at high temperature; however, the exact mechanism is still debated. Because volatilization can fractionate isotopes, comparing the Isotopic composition of volatile elements in tektites with those of their source rocks may help to understand the physical conditions during tektite formation. Interestingly, volatile chalcophile elements (e.g., Cd and Zn) seem to be the only elements for which Isotopic Fractionation is known so far in tektites. Here, we extend this study to Cu, another volatile chalcophile element. We have measured the Cu Isotopic composition for 20 tektite samples from the four known different strewn fields. All of the tektites (except the Muong Nong-types) are enriched in the heavy isotopes of Cu (1.98 < delta(61)Cu < 6.99) in comparison to the terrestrial crust (delta(65)Cu approximate to 0) with no clear distinction between the different groups. The Muong Nong-type tektites and a Libyan Desert Glass sample are not fractionated, (delta(65)Cu approximate to 0) in comparison to the terrestrial crust. To refine the Cu Isotopic composition of the terrestrial crust, we also present data for three geological reference materials (delta(65)Cu approximate to 0). An increase of delta(65)Cu with decreasing Cu abundance probably reflects that the Isotopic Fractionation occurred by evaporation during heating. A simple Rayleigh distillation cannot explain the Cu Isotopic data and we suggest that the Isotopic Fractionation is governed by a diffusion-limited regime. Copper is Isotopically more fractionated than the more volatile element Zn (delta(66/64)Zn up to 2.49 parts per thousand). This difference of behavior between Cu and Zn is predicted in a diffusion-limited regime, where the magnitude of the Isotopic Fractionation is regulated by the competition between the evaporative flux and the diffusive flux at the diffusion boundary layer. Due to the difference of ionic charge in silicates (Zn(2+) vs. Cu(+)), Cu has a diffusion coefficient that is larger than that of Zn by at least two orders of magnitude. Therefore, the larger Isotopic Fractionation in Cu than in Zn in tektites is due to the significant difference in their respective chemical diffusivity. (C) 2009 Elsevier Ltd. All rights reserved.