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Spangenberg JE, Bosco-Santos A. Sulfur isotope analyses using 3× elemental analysis/isotope ratio mass spectrometry: Saving helium and energy while reducing analytical time and costs. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2024; 38:e9866. [PMID: 39041642 DOI: 10.1002/rcm.9866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 06/21/2024] [Accepted: 06/23/2024] [Indexed: 07/24/2024]
Abstract
RATIONALE Helium (He) and energy shortages have caused price increases and reduced their availability. Using three combustion reactions per acquisition of carbon and nitrogen isotope ratios saves 50% He and energy during the elemental analysis/isotope ratio mass spectrometry (EA/IRMS). This approach needs to be tested for sulfur isotope (δ34S) analyses. METHODS A new method to measure δ34S in three sequential combustion reactions within one EA/IRMS acquisition was developed. The same material or blank samples could be used in the three reactions. After SO2 was used, a N2 purging method was employed to prolong the lifetime of the valves in the EA/IRMS interface. The 3×EA/IRMS was applied to measure δ34S in precious samples, such as Ag2S from acid-volatile and chromium-reducible sulfur extracted with a multiple-port setup. RESULTS The 3×EA/IRMS-δ34S method was validated with replicate analyses of international reference materials and laboratory standards with a wide range of mineralogical compositions and δ34S values. The method provided a strategic advantage for the δ34S measurements of small precious samples (measured between blanks). The accuracy and precision of the 3×EA/IRMS values effectively matched those obtained using conventional EA/IRMS, with good agreement between the mean ± SD values and the recommended values with their uncertainties. CONCLUSIONS Compared with the conventional EA/IRMS, the proposed method provides accurate and precise δ34S measurements of the sulfate and sulfide samples while saving approximately 50% of He, energy, SO2 reference gas, O2, analysis time, and cost. Notably, 3×EA/IRMS can provide up to three δ34S values unaffected by memory effects.
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Affiliation(s)
- Jorge E Spangenberg
- Institute of Earth Surface Dynamics (IDYST), University of Lausanne, Lausanne, Switzerland
| | - Alice Bosco-Santos
- Institute of Earth Surface Dynamics (IDYST), University of Lausanne, Lausanne, Switzerland
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Zhao C, Guo Q, Zhang T, Han X, Usman D. Procedures from samples to sulfur isotopic data: A review. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2024; 38:e9733. [PMID: 38591181 DOI: 10.1002/rcm.9733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 01/31/2024] [Accepted: 02/18/2024] [Indexed: 04/10/2024]
Abstract
RATIONALE Sulfur isotopes have been widely used to solve some key scientific questions, especially in the last two decades with advanced instruments and analytical schemes. Different sulfur speciation and multiple isotopes analyzed in laboratories worldwide and in situ microanalysis have also been reported in many articles. However, methods of sampling to measurements are multifarious, and occasionally some inaccuracies are present in published papers. Vague methods may mislead newcomers to the field, puzzle readers, or lead to incorrect data-based correlations. METHODS We have reviewed multiple methods on sulfur isotopic analyses from the perspectives of sampling, laboratory work, and instrumental analysis in order to help reduce operational inhomogeneity and ensure the fidelity of sulfur isotopic data. We do not deem our proposed solutions as the ultimate standard methods but as a lead-in to the overall introduction and summary of the current methods used. RESULTS It has been shown that external contamination and transformation of different sulfur species should be avoided during the sampling, pretreatment, storage, and chemical treatment processes. Conversion rates and sulfur isotopic fractionations during sulfur extraction, purification, and conversion processes must be verified by researchers using standard or known samples. The unification of absence of isotopic fractionation is needed during all steps, and long-term monitoring of standard samples is recommended. CONCLUSION This review compiles more details on different methods in sampling, laboratory operation, and measurement of sulfur isotopes, which is beneficial for researchers' better practice in laboratories. Microanalyses and molecular studies are the frontier techniques that compare the bulk sample with the elemental analysis/continuous flow-gas source stable isotope ratio mass spectrometry method, but the latter is widely used. The development of sulfur isotopic measurements will lead to the innovation in scientific issues with sulfur proxies.
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Affiliation(s)
- Changqiu Zhao
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qingjun Guo
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Tonggang Zhang
- College of Geosciences, China University of Petroleum, Beijing, China
| | - Xiaokun Han
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
| | - Dawuda Usman
- Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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Spangenberg JE, Saintilan NJ, Palinkaš SS. Safe, accurate, and precise sulfur isotope analyses of arsenides, sulfarsenides, and arsenic and mercury sulfides by conversion to barium sulfate before EA/IRMS. Anal Bioanal Chem 2022; 414:2163-2179. [PMID: 35066601 PMCID: PMC8821489 DOI: 10.1007/s00216-021-03854-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 12/03/2021] [Accepted: 12/15/2021] [Indexed: 11/28/2022]
Abstract
AbstractThe stable isotope ratios of sulfur (δ34S relative to Vienna Cañon Diablo Troilite) in sulfates and sulfides determined by elemental analysis and isotope ratio mass spectrometry (EA/IRMS) have been proven to be a remarkable tool for studies of the (bio)geochemical sulfur cycles in modern and ancient environments. However, the use of EA/IRMS to measure δ34S in arsenides and sulfarsenides may not be straightforward. This difficulty can lead to potential health and environmental hazards in the workplace and analytical problems such as instrument contamination, memory effects, and a non-matrix-matched standardization of δ34S measurements with suitable reference materials. To overcome these practical and analytical challenges, we developed a procedure for sulfur isotope analysis of arsenides, which can also be safely used for EA/IRMS analysis of arsenic sulfides (i.e., realgar, orpiment, arsenopyrite, and arsenian pyrite), and mercury sulfides (cinnabar). The sulfur dioxide produced from off-line EA combustion was trapped in an aqueous barium chloride solution in a leak-free system and precipitated as barium sulfate after quantitative oxidation of hydrogen sulfite by hydrogen peroxide. The derived barium sulfate was analyzed by conventional EA/IRMS, which bracketed the δ34S values of the samples with three international sulfate reference materials. The protocol (BaSO4-EA/IRMS) was validated by analyses of reference materials and laboratory standards of sulfate and sulfides and achieved accuracy and precision comparable with those of direct EA/IRMS. The δ34S values determined by BaSO4-EA/IRMS in sulfides (arsenopyrite, arsenic, and mercury sulfides) samples from different origins were comparable to those obtained by EA/IRMS, and no sulfur isotope fractionations were introduced during sample preparation. We report the first sulfur isotope data of arsenides obtained by BaSO4-EA/IRMS.
Graphical abstract
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Affiliation(s)
- Jorge E Spangenberg
- Institute of Earth Surface Dynamics (IDYST), University of Lausanne, 1015, Lausanne, Switzerland.
| | - Nicolas J Saintilan
- Institute of Geochemistry and Petrology, Department of Earth Sciences, ETH, 8092, Zürich, Switzerland
| | - Sabina Strmić Palinkaš
- Department of Geosciences, UiT The Arctic University of Norway in Tromsø, 9037, Tromsø, Norway
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Cooccurring Activities of Two Autotrophic Pathways in Symbionts of the Hydrothermal Vent Tubeworm Riftia pachyptila. Appl Environ Microbiol 2021; 87:e0079421. [PMID: 34190607 DOI: 10.1128/aem.00794-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Genome and proteome data predict the presence of both the reductive citric acid cycle (rCAC; also called the reductive tricarboxylic acid cycle) and the Calvin-Benson-Bassham cycle (CBB) in "Candidatus Endoriftia persephonae," the autotrophic sulfur-oxidizing bacterial endosymbiont from the giant hydrothermal vent tubeworm Riftia pachyptila. We tested whether these cycles were differentially induced by sulfide supply, since the synthesis of biosynthetic intermediates by the rCAC is less energetically expensive than that by the CBB. R. pachyptila was incubated under in situ conditions in high-pressure aquaria under low (28 to 40 μmol · h-1) or high (180 to 276 μmol · h-1) rates of sulfide supply. Symbiont-bearing trophosome samples excised from R. pachyptila maintained under the two conditions were capable of similar rates of CO2 fixation. Activities of the rCAC enzyme ATP-dependent citrate lyase (ACL) and the CBB enzyme 1,3-bisphosphate carboxylase/oxygenase (RubisCO) did not differ between the two conditions, although transcript abundances for ATP-dependent citrate lyase were 4- to 5-fold higher under low-sulfide conditions. δ13C values of internal dissolved inorganic carbon (DIC) pools were varied and did not correlate with sulfide supply rate. In samples taken from freshly collected R. pachyptila, δ13C values of lipids fell between those collected for organisms using either the rCAC or the CBB exclusively. These observations are consistent with cooccurring activities of the rCAC and the CBB in this symbiosis. IMPORTANCE Previous to this study, the activities of the rCAC and CBB in R. pachyptila had largely been inferred from "omics" studies of R. pachyptila without direct assessment of in situ conditions prior to collection. In this study, R. pachyptila was maintained and monitored in high-pressure aquaria prior to measuring its CO2 fixation parameters. Results suggest that ranges in sulfide concentrations similar to those experienced in situ do not exert a strong influence on the relative activities of the rCAC and the CBB. This observation highlights the importance of further study of this symbiosis and other organisms with multiple CO2-fixing pathways, which recent genomics and biochemical studies suggest are likely to be more prevalent than anticipated.
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Bryant RN, Jones C, Raven MR, Gomes ML, Berelson WM, Bradley AS, Fike DA. Sulfur isotope analysis of microcrystalline iron sulfides using secondary ion mass spectrometry imaging: Extracting local paleo-environmental information from modern and ancient sediments. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33:491-502. [PMID: 30561860 DOI: 10.1002/rcm.8375] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 12/11/2018] [Accepted: 12/14/2018] [Indexed: 06/09/2023]
Abstract
RATIONALE Sulfur isotope ratio measurements of bulk sulfide from marine sediments have often been used to reconstruct environmental conditions associated with their formation. In situ microscale spot analyses by secondary ion mass spectrometry (SIMS) and laser ablation multiple-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) have been utilized for the same purpose. However, these techniques are often not suitable for studying small (≤10 μm) grains or for detecting intra-grain variability. METHODS Here, we present a method for the physical extraction (using lithium polytungstate heavy liquid) and subsequent sulfur isotope analysis (using SIMS; CAMECA IMS 7f-GEO) of microcrystalline iron sulfides. SIMS sulfur isotope ratio measurements were made via Cs+ bombardment of raster squares with sides of 20-130 μm, using an electron multiplier (EM) detector to collect counts of 32 S- and 34 S- for each pixel (128 × 128 pixel grids) for between 20 and 960 cycles. RESULTS The extraction procedure did not discernibly alter pyrite grain-size distributions. The apparent inter-grain variability in 34 S/32 S in 1-4 μm-sized pyrite and marcasite fragments from isotopically homogeneous hydrothermal crystals was ~ ±2‰ (1σ), comparable with the standard error of the mean for individual measurements (≤ ±2‰, 1σ). In contrast, grain-specific 34 S/32 S ratios in modern and ancient sedimentary pyrites and marcasites can have inter- and intra-grain variability >60‰. The distributions of intra-sample isotopic variability are consistent with bulk 34 S/32 S values. CONCLUSIONS SIMS analyses of isolated iron sulfide grains yielded distributions that are isotopically representative of bulk 34 S/32 S values. Populations of iron sulfide grains from sedimentary samples record the evolution of the S-isotopic composition of pore water sulfide in their S-isotopic compositions. These data allow past local environmental conditions to be inferred.
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Affiliation(s)
- Roger N Bryant
- Department of Earth & Planetary Sciences, Washington University in Saint Louis, St Louis, MO, 63130, USA
| | - Clive Jones
- Department of Earth & Planetary Sciences, Washington University in Saint Louis, St Louis, MO, 63130, USA
| | - Morgan R Raven
- Department of Earth & Planetary Sciences, Washington University in Saint Louis, St Louis, MO, 63130, USA
- Department of Earth Science, University of California, Santa Barbara, CA, 93106-9630, USA
| | - Maya L Gomes
- Department of Earth & Planetary Sciences, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - William M Berelson
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, 90089-0740, USA
| | - Alexander S Bradley
- Department of Earth & Planetary Sciences, Washington University in Saint Louis, St Louis, MO, 63130, USA
| | - David A Fike
- Department of Earth & Planetary Sciences, Washington University in Saint Louis, St Louis, MO, 63130, USA
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Yang LW, Liu C, Yang T. An evaluation on the extraction capability of anion exchange membranes for high-precision sulfur isotope measurement by multiple-collector inductively coupled plasma mass spectrometry. RSC Adv 2019; 9:31224-31232. [PMID: 35527964 PMCID: PMC9072498 DOI: 10.1039/c9ra04121d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 09/23/2019] [Indexed: 11/21/2022] Open
Abstract
Anion exchange membranes (AEMs) are adept at extracting sulfate for sulfur isotope analyses by multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) from natural samples typically with low sulfate concentrations.
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Affiliation(s)
- Liu Willow Yang
- State Key Laboratory for Mineral Deposits Research
- School of Earth Sciences and Engineering
- Nanjing University
- Nanjing 210093
- P. R. China
| | - Chenhui Liu
- State Key Laboratory for Mineral Deposits Research
- School of Earth Sciences and Engineering
- Nanjing University
- Nanjing 210093
- P. R. China
| | - Tao Yang
- State Key Laboratory for Mineral Deposits Research
- School of Earth Sciences and Engineering
- Nanjing University
- Nanjing 210093
- P. R. China
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Muscovite 40Ar/39Ar Age and H-O-S Isotopes of the Shimensi Tungsten Deposit (Northern Jiangxi Province, South China) and Their Metallogenic Implications. MINERALS 2017. [DOI: 10.3390/min7090162] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Liu C, Bian XP, Yang T, Lin AJ, Jiang SY. Matrix effects of calcium on high-precision sulfur isotope measurement by multiple-collector inductively coupled plasma mass spectrometry. Talanta 2016; 151:132-140. [PMID: 26946020 DOI: 10.1016/j.talanta.2016.01.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 12/30/2015] [Accepted: 01/08/2016] [Indexed: 11/29/2022]
Abstract
Multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) has been successfully applied in the rapid and high-precision measurement for sulfur isotope ratios in recent years. During the measurement, the presence of matrix elements would affect the instrumental mass bias for sulfur and these matrix-induced effects have aroused a lot of researchers' interest. However, these studies have placed more weight on highlighting the necessity for their proposed correction protocols (e.g., chemical purification and matrix-matching) while less attention on the key property of the matrix element gives rise to the matrix effects. In this study, four groups of sulfate solutions, which have different concentrations of sulfur (0.05-0.60mM) but a constant sequence of atomic calcium/sulfur ratios (0.1-50), are investigated under wet (solution) and dry (desolvation) plasma conditions to make a detailed evaluation on the matrix effects from calcium on sulfur isotope measurement. Based on a series of comparative analyses, we indicated that, the matrix effects of calcium on both measured sulfur isotope ratios and detected (32)S signal intensities are dependent mainly on the absolute calcium concentration rather than its relative concentration ratio to sulfur (i.e., atomic calcium/sulfur ratio). Also, for the same group of samples, the matrix effects of calcium under dry plasma condition are much more significant than that of wet plasma. This research affords the opportunity to realize direct and relatively precise sulfur isotope measurement for evaporite gypsum, and further provides some suggestions with regard to sulfur isotope analytical protocols for sedimentary pore water.
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Affiliation(s)
- Chenhui Liu
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, PR China; Collaborative Innovation Center of South China Sea Studies, Nanjing University, Nanjing 210093, PR China
| | - Xiao-Peng Bian
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, PR China; Collaborative Innovation Center of South China Sea Studies, Nanjing University, Nanjing 210093, PR China
| | - Tao Yang
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, PR China; Beijing SHRIMP Center, Institute of Geology Chinese Academy of Geological Sciences, Beijing 102206, PR China; Collaborative Innovation Center of South China Sea Studies, Nanjing University, Nanjing 210093, PR China.
| | - An-Jun Lin
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, PR China; Thermo Fisher Scientific China Co., Ltd, Guangzhou 510030, PR China
| | - Shao-Yong Jiang
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, PR China; State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, PR China; Faculty of Earth Resources and Collaborative Innovation Center for Scarce and Strategic Mineral Resources, China University of Geosciences, Wuhan 430074, PR China
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Hanousek O, Berger TW, Prohaska T. MC ICP-MS δ(34)S(VCDT) measurement of dissolved sulfate in environmental aqueous samples after matrix separation by means of an anion exchange membrane. Anal Bioanal Chem 2015; 408:399-407. [PMID: 26438477 PMCID: PMC4709390 DOI: 10.1007/s00216-015-9053-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 09/14/2015] [Accepted: 09/15/2015] [Indexed: 12/03/2022]
Abstract
Analysis of 34S/32S of sulfate in rainwater and soil solutions can be seen as a powerful tool for the study of the sulfur cycle. Therefore, it is considered as a useful means, e.g., for amelioration and calibration of ecological or biogeochemical models. Due to several analytical limitations, mainly caused by low sulfate concentration in rainwater, complex matrix of soil solutions, limited sample volume, and high number of samples in ecosystem studies, a straightforward analytical protocol is required to provide accurate S isotopic data on a large set of diverse samples. Therefore, sulfate separation by anion exchange membrane was combined with precise isotopic measurement by multicollector inductively coupled plasma mass spectrometry (MC ICP-MS). The separation method proved to be able to remove quantitatively sulfate from matrix cations (Ca, K, Na, or Li) which is a precondition in order to avoid a matrix-induced analytical bias in the mass spectrometer. Moreover, sulfate exchange on the resin is capable of preconcentrating sulfate from low concentrated solutions (to factor 3 in our protocol). No significant sulfur isotope fractionation was observed during separation and preconcentration. MC ICP-MS operated at edge mass resolution has enabled the direct 34S/32S analysis of sulfate eluted from the membrane, with an expanded uncertainty U (k = 2) down to 0.3 ‰ (a single measurement). The protocol was optimized and validated using different sulfate solutions and different matrix compositions. The optimized method was applied in a study on solute samples retrieved in a beech (Fagus sylvatica) forest in the Vienna Woods. Both rainwater (precipitation and tree throughfall) and soil solution δ34SVCDT ranged between 4 and 6 ‰, the ratio in soil solution being slightly lower. The lower ratio indicates that a considerable portion of the atmospherically deposited sulfate is cycled through the organic S pool before being released to the soil solution. Nearly the same trends and variations were observed in soil solution and rainwater δ34SVCDT values showing that sulfate adsorption/desorption are not important processes in the studied soil. Sulfate separation by means of an anion exchange resin on a plastic membrane ![]()
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Affiliation(s)
- Ondrej Hanousek
- VIRIS Laboratory, Department of Chemistry, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 24, 3430, Tulln, Austria.,Institute of Forest Ecology, Department of Forest- and Soil Sciences, University of Natural Resources and Life Sciences Vienna, Peter-Jordan-Strasse 82, 1190, Vienna, Austria
| | - Torsten W Berger
- Institute of Forest Ecology, Department of Forest- and Soil Sciences, University of Natural Resources and Life Sciences Vienna, Peter-Jordan-Strasse 82, 1190, Vienna, Austria
| | - Thomas Prohaska
- VIRIS Laboratory, Department of Chemistry, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 24, 3430, Tulln, Austria.
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Benkó Z, Mogessie A, Molnár F, Krenn K, Poulson SR, Hauck S, Severson M, Arehart GB. Hydrothermal alteration and Cu-Ni-PGE mobilization in the charnockitic rocks of the footwall of the South Kawishiwi intrusion, Duluth Complex, USA. ORE GEOLOGY REVIEWS 2015; 67:170-188. [PMID: 26594080 PMCID: PMC4617465 DOI: 10.1016/j.oregeorev.2014.11.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 09/14/2014] [Accepted: 11/17/2014] [Indexed: 06/05/2023]
Abstract
In the Neoarchean (~ 2.7 Ga) contact metamorphosed charnockitic footwall of the Mesoproterosoic (1.1 Ga) South Kawishiwi intrusion of the Duluth Complex, the primary metamorphic mineral assemblage and Cu-Ni-PGE sulfide mineralization is overprinted by an actinolite + chlorite + cummingtonite + prehnite + pumpellyite + quartz + calcite hydrothermal mineral assemblage along 2-3 cm thick veins. In calcite, hosted by the hydrothermal alteration zones and in a single recrystallized quartz porphyroblast, four different fluid inclusion assemblages are documented; the composition of these fluid inclusions provide p-T conditions of the fluid flow, and helps to define the origin of the fluids and evaluate their role in the remobilization and reprecipitation of the primary metamorphic sulfide assemblage. Pure CO2 fluid inclusions were found as early inclusions in recrystallized quartz porphyroblast. These inclusions may have been trapped during the recrystallization of the quartz during the contact metamorphism of the footwall charnockite in the footwall of the SKI. The estimated trapping pressure (1.6-2.0 kbar) and temperature (810-920 °C) conditions correspond to estimates based on felsic veins in the basal zones of the South Kawishiwi intrusion. Fluid inclusion assemblages with CO2-H2O-NaCl and CH4-N2-H2O-NaCl compositions found in this study along healed microfractures in the recrystallized quartz porphyroblast establish the heterogeneous state of the fluids during entrapment. The estimated trapping pressure and temperature conditions (240-650 bar and 120-150 °C for CO2-H2O-NaCl inclusions and 315-360 bar and 145-165 °C for CH4-N2-H2O-NaCl inclusions) are significantly lower than the p-T conditions (> 700 °C and 1.6-2 kbar) during the contact metamorphism, indicating that this fluid flow might not be related to the cooling of the Duluth Complex and its contact aureole. The presence of chalcopyrite inclusions in these fluid inclusions and in the trails of these fluid inclusion assemblages confirms that at least on local scale these fluids played a role in base metal remobilization. No evidences have been observed for PGE remobilization and transport in the samples. The source of the carbonic phase in the carbonic assemblages (CO2; CH4) could be the graphite, present in the metasedimentary hornfelsed inclusions in the basal zones of the South Kawishiwi intrusion. The hydrothermal veins in the charnockite can be characterized by an actinolite + cummingtonite + chlorite + prehnite + pumpellyite + calcite (I-II) + quartz mineral assemblage. Chlorite thermometry yields temperatures around 276-308 °C during the earliest phase of the fluid flow. In the late calcite (II) phase, high salinity (21.6-28.8 NaCl + CaCl2 equiv. wt.%), low temperature (90-160 °C), primary aqueous inclusions were found. Chalcopyrite (± sphalerite ± millerite), replacing and intersecting the early hydrothermal phases, are associated to the late calcite (II) phase. The composition of the formational fluids in the Canadian Shield is comparable with the composition of the studied fluid inclusions. This suggests that the composition of the fluids did not change in the past 2 Ga and base metal remobilization by formational fluids could have taken place any time after the formation of the South Kawishiwi intrusion. Sulfur isotope studies carried out on the primary metamorphic (δ34S = 7.4-8.9‰) and the hydrothermal sulfide mineral assemblage (δ34S = 5.5-5.7‰) proves, that during the hydrothermal fluid flow the primary metamorphic ores were remobilized.
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Affiliation(s)
- Zsolt Benkó
- Institute of Earth Sciences, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Aberra Mogessie
- Institute of Earth Sciences, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Ferenc Molnár
- Geological Survey of Finland, Betonimiehenkuja 4, 02151 Espoo, Finland
| | - Kurt Krenn
- Institute of Earth Sciences, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Simon R. Poulson
- Department of Geological Sciences & Engineering, University of Nevada — Reno, 1664 N. Virginia St., Reno, NV 89557-0138, USA
| | - Steven Hauck
- Natural Resources Research Institute, University of Minnesota, 5013 Miller Trunk Highway, Duluth, MN 55811-1442, USA
| | - Mark Severson
- Natural Resources Research Institute, University of Minnesota, 5013 Miller Trunk Highway, Duluth, MN 55811-1442, USA
| | - Greg B. Arehart
- Department of Geological Sciences & Engineering, University of Nevada — Reno, 1664 N. Virginia St., Reno, NV 89557-0138, USA
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Rapid and high-precision measurement of sulfur isotope and sulfur concentration in sediment pore water by multi-collector inductively coupled plasma mass spectrometry. Talanta 2014; 132:8-14. [PMID: 25476272 DOI: 10.1016/j.talanta.2014.08.053] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Revised: 08/06/2014] [Accepted: 08/07/2014] [Indexed: 11/22/2022]
Abstract
We have developed a technique for the rapid, precise and accurate determination of sulfur isotopes (δ(34)S) by MC-ICP-MS applicable to a range of sulfur-bearing solutions of different sulfur content. The 10 ppm Alfa-S solution (ammonium sulfate solution, working standard of the lab of the authors) was used to bracket other Alfa-S solutions of different concentrations and the measured δ(34)SV-CDT values of Alfa-S solutions deviate from the reference value to varying degrees (concentration effect). The stability of concentration effect has been verified and a correction curve has been constructed based on Alfa-S solutions to correct measured δ(34)SV-CDT values. The curve has been applied to AS solutions (dissolved ammonium sulfate from the lab of the authors) and pore water samples successfully, validating the reliability of our analytical method. This method also enables us to measure the sulfur concentration simultaneously when analyzing the sulfur isotope composition. There is a strong linear correlation (R(2)>0.999) between the sulfur concentrations and the intensity ratios of samples and the standard. We have constructed a regression curve based on Alfa-S solutions and this curve has been successfully used to determine sulfur concentrations of AS solutions and pore water samples. The analytical technique presented here enable rapid, precise and accurate S isotope measurement for a wide range of sulfur-bearing solutions - in particular for pore water samples with complex matrix and varying sulfur concentrations. Also, simultaneous measurement of sulfur concentrations is available.
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Lin AJ, Yang T, Jiang SY. A rapid and high-precision method for sulfur isotope δ(34)S determination with a multiple-collector inductively coupled plasma mass spectrometer: matrix effect correction and applications for water samples without chemical purification. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2014; 28:750-756. [PMID: 24573806 DOI: 10.1002/rcm.6838] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Revised: 01/11/2014] [Accepted: 01/13/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Previous studies have indicated that prior chemical purification of samples, although complex and time-consuming, is essential in obtaining precise and accurate results for sulfur isotope ratios using multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). In this study, we introduce a new, rapid and precise MC-ICP-MS method for sulfur isotope determination from water samples without chemical purification. METHODS The analytical work was performed on an MC-ICP-MS instrument with medium mass resolution (m/Δm ~ 3000). Standard-sample bracketing (SSB) was used to correct samples throughout the analytical sessions. Reference materials included an Alfa-S (ammonium sulfate) standard solution, ammonium sulfate provided by the lab of the authors and fresh seawater from the South China Sea. A range of matrix-matched Alfa-S standard solutions and ammonium sulfate solutions was used to investigate the matrix (salinity) effect (matrix was added in the form of NaCl). A seawater sample was used to confirm the reliability of the method. RESULTS Using matrix-matched (salinity-matched) Alfa-S as the working standard, the measured δ(34)S value of AS (-6.73 ± 0.09‰) was consistent with the reference value (-6.78 ± 0.07‰) within the uncertainty, suggesting that this method could be recommended for the measurement of water samples without prior chemical purification. The δ(34)S value determination for the unpurified seawater also yielded excellent results (21.03 ± 0.18‰) that are consistent with the reference value (20.99‰), thus confirming the feasibility of the technique. CONCLUSIONS The data and the results indicate that it is feasible to use MC-ICP-MS and matrix-matched working standards to measure the sulfur isotopic compositions of water samples directly without chemical purification. In comparison with the existing MC-ICP-MS techniques, the new method is better for directly measuring δ(34)S values in water samples with complex matrices; therefore, it can significantly accelerate analytical turnover.
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Affiliation(s)
- An-Jun Lin
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, 210093, P.R.China
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Moyes AB, Schauer AJ, Siegwolf RTW, Bowling DR. An injection method for measuring the carbon isotope content of soil carbon dioxide and soil respiration with a tunable diode laser absorption spectrometer. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2010; 24:894-900. [PMID: 20201033 DOI: 10.1002/rcm.4466] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We present a novel technique in which the carbon isotope ratio (delta(13)C) of soil CO(2) is measured from small gas samples (<5 mL) injected into a stream of CO(2)-free air flowing into a tunable diode laser absorption spectrometer (TDL). This new method extends the dynamic range of the TDL to measure CO(2) mole fractions ranging from ambient to pure CO(2), reduces the volume of sample required to a few mL, and does not require field deployment of the instrument. The measurement precision of samples stored for up to 60 days was 0.23 per thousand. The new TDL method was applied with a simple gas well sampling technique to obtain and measure gas samples from shallow soil depth increments for CO(2) mole fraction and delta(13)C analysis, and subsequent determination of the delta(13)C of soil-respired CO(2). The method was tested using an artificial soil system containing a controlled CO(2) source and compared with an independent method using the TDL and an open soil chamber. The profile and chamber estimates of delta(13)C of an artificially produced CO(2) flux were consistent and converged to the delta(13)C of the CO(2) source at steady state, indicating the accuracy of both methods under controlled conditions. The new TDL method, in which a small pulse of sample is measured on a carrier gas stream, is analogous for the TDL technique to the development of continuous-flow configurations for isotope ratio mass spectrometry. While the applications presented here are focused on soil CO(2), this new TDL method could be applied in a number of situations requiring measurement of delta(13)C of CO(2) in small gas samples with ambient to high CO(2) mole fractions.
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Affiliation(s)
- Andrew B Moyes
- Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112, USA.
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Mann JL, Vocke RD, Kelly WR. Revised delta34S reference values for IAEA sulfur isotope reference materials S-2 and S-3. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2009; 23:1116-1124. [PMID: 19288548 DOI: 10.1002/rcm.3977] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Revised delta(34)S reference values with associated expanded uncertainties (95% confidence interval (C.I.)) are presented for the sulfur isotope reference materials IAEA-S-2 (22.62 +/- 0.16 per thousand) and IAEA-S-3 (-32.49 +/- 0.16 per thousand). These revised values are determined using two relative-difference measurement techniques, gas source isotope ratio mass spectrometry (GIRMS) and double-spike multi-collector thermal ionization mass spectrometry (MC-TIMS). Gas analyses have traditionally been considered the most robust for relative isotopic difference measurements of sulfur. The double-spike MC-TIMS technique provides an independent method for value-assignment validation and produces revised values that are both unbiased and more precise than previous value assignments. Unbiased delta(34)S values are required to anchor the positive and negative end members of the sulfur delta (delta) scale because they are the basis for reporting both delta(34)S values and the derived mass-independent Delta(33)S and Delta(36)S values.
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Affiliation(s)
- Jacqueline L Mann
- Inorganic Chemical Metrology Group, Analytical Chemistry Division, National Institute of Standards and Technology, 100 Bureau Drive, MS8391, Gaithersburg, MD 20899, USA.
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Druhan JL, Conrad ME, Williams KH, N'Guessan L, Long PE, Hubbard SS. Sulfur isotopes as indicators of amended bacterial sulfate reduction processes influencing field scale uranium bioremediation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:7842-7849. [PMID: 19031870 DOI: 10.1021/es800414s] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Aqueous uranium (U(VI)) concentrations in a contaminated aquifer in Rifle Colorado have been successfully lowered through electron donor amended bioreduction. Samples collected during the acetate amendment experiment were analyzed for aqueous concentrations of Fe(ll), sulfate, sulfide, acetate, U(VI), and delta(34)S of sulfate and sulfide to explore the utility of sulfur isotopes as indicators of in situ acetate amended sulfate and uranium bioreduction processes. Enrichment of up to 7% per hundred in delta(34)S of sulfate in down-gradient monitoring wells indicates a transition to elevated bacterial sulfate reduction. A depletion in Fe(II), sulfate, and sulfide concentrations atthe height of sulfate reduction, along with an increase in the delta(34)S of sulfide to levels approaching the delta(34)S values of sulfate, indicates sulfate limited conditions concurrent with a rebound in U(VI) concentrations. Upon cessation of acetate amendment, sulfate and sulfide concentrations increased, while delta(34)S values of sulfide returned to less than -20% per hundred and sulfate delta(34)S decreased to near-background values, indicating lower levels of sulfate reduction accompanied by a corresponding drop in U(VI). Results indicate a transition between electron donor and sulfate-limited conditions at the height of sulfate reduction and suggest stability of biogenic FeS precipitates following the end of acetate amendment.
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Affiliation(s)
- Jennifer L Druhan
- Department of Earth and Planetary Science, University of California, Berkeley, California 94720, USA.
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Fritzsche F, Tichomirowa M. Signal improvement in elemental analyzer/continuous flow isotope ratio mass spectrometry for samples with low sulfur contents using a pre-concentration technique for on-line concentration adjustment. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:1679-82. [PMID: 16637004 DOI: 10.1002/rcm.2488] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Elemental analyzer/continuous flow isotope ratio mass spectrometry (EA/CF-IRMS) has become a standard procedure for the determination of delta(34)S values. Common procedures are, however, frequently less than satisfactory for organic as well as for mineral samples with very low concentrations of sulfur (<2000 ppm). Here we present a method which employs cold trapping of SO(2) to adjust the gas concentration for subsequent isotope signature determination. Analytical accuracy is comparable with common EA/CF-IRMS analysis without trapping, showing a precision of better than +/-0.4 per thousand in delta(34)S (1 SD). The virtual absence of memory effects was established by analyzing adjacent samples exhibiting a large difference in delta(34)S and by prolonged freezing of the carrier gas, yielding virtually no S concentration peak. The method was tested using less than 15% (6 microg) of the S required for a conventional isotope analysis at comparable signal intensity. Even smaller samples can be analyzed with high precision. This facilitates the on-line delta(34)S determination in small biological and mineral samples, minimizing matrix effects in various materials including sandstone, soil, and plant samples.
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Affiliation(s)
- Florian Fritzsche
- Institute of Soil Science and Soil Geography, University of Bayreuth, 95440 Bayreuth, Germany.
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Poulson SR. The effect of sulfate-delta18O upon on-line sulfate-delta34S analysis, and implications for measurements of delta33S and Delta33S. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:105-107. [PMID: 15593062 DOI: 10.1002/rcm.1754] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
On-line delta34S analysis of sulfate using an elemental analyzer has a number of advantages vs. conventional off-line techniques, such as ease of operation, rapidity, and the requirement for small amounts of material. Although the analyses are performed by converting sulfate into SO2 gas, the effect of sulfate-delta18O composition upon the SO2-delta18O composition and the value of delta66 during elemental analysis, and ultimately the calculated sulfate-delta34S composition, has rarely been addressed. Three BaSO4 samples were prepared with known identical delta34S compositions, but with a wide range of delta18O compositions. delta18O values were shown to range over 40 per thousand, but conventional on-line delta34S analyses verified that the sulfate-delta34S compositions were identical. These results indicate that conventional on-line analysis of sulfate-delta34S is unaffected by the value of sulfate-delta18O, and suggest that sulfide-delta34S standards can be used to calibrate sulfate-delta34S analyses (and vice versa). Moreover, these results suggest that it may be possible to use on-line sulfur isotope analysis of SO2 to measure delta33S and Delta33S in addition to delta34S, as a faster and safer alternative to the SF6 technique currently utilized, and hence promote further study of mass-independent sulfur isotope fractionation effects.
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Affiliation(s)
- Simon R Poulson
- Department of Geological Sciences MS-172, University of Nevada-Reno, Reno, NV 89557, USA.
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Croft DJ, Pye K. Multi-technique comparison of source and primary transfer soil samples: an experimental investigation. Sci Justice 2004; 44:21-8. [PMID: 14964818 DOI: 10.1016/s1355-0306(04)71681-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The comparison of soil samples is of long-standing and increasing interest in forensic science. Routine comparisons should involve the use of several techniques in combination. A wide range of analytical techniques can be used, choice being dependent on several factors including sample size and character, time constraints and cost limitations. In this paper results are presented for experiments carried out to test the effectiveness of four of the available analytical techniques (spectro-photometric colour determination, laser diffraction particle size analysis, stable isotope analysis and chemical element analysis) used to compare single source and primary transfer soil samples. Four soil types and five footwear types were used. All four techniques showed excellent precision and good resolving power between soil types. Only relatively small differences were obtained between source and transferred soil samples in terms of colour, stable carbon and nitrogen isotope ratios and elemental chemistry. Slight but significant differences were found in grain size, indicating that the primary transfer process is to some extent grain size selective.
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Affiliation(s)
- D J Croft
- Kenneth Pye Associates Ltd., Crowthorne Business Estate, Old Wokingham Road, Crowthorne, Berkshire RG45 6AW, United Kingdom
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Alexander B, Thiemens MH, Farquhar J, Kaufman AJ, Savarino J, Delmas RJ. East Antarctic ice core sulfur isotope measurements over a complete glacial-interglacial cycle. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2003jd003513] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- B. Alexander
- Department of Chemistry and Biochemistry; University of California, San Diego; La Jolla California USA
| | - M. H. Thiemens
- Department of Chemistry and Biochemistry; University of California, San Diego; La Jolla California USA
| | - J. Farquhar
- Earth Systems Science Interdisciplinary Center and Department of Geology; University of Maryland; College Park Maryland USA
| | - A. J. Kaufman
- Earth Systems Science Interdisciplinary Center and Department of Geology; University of Maryland; College Park Maryland USA
| | - J. Savarino
- Laboratoire de Glaciologie et Géophysique de l'Environnement; St. Martin d'Hères France
| | - R. J. Delmas
- Laboratoire de Glaciologie et Géophysique de l'Environnement; St. Martin d'Hères France
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Affiliation(s)
- Michael E. Lipschutz
- Department of Chemistry, Wetherill Laboratory, 560 Oval Drive, Purdue University, West Lafayette, Indiana 47907-2038, Department of Chemistry, Indiana State University, Terre Haute, Indiana 47809-5901, and Department of Earth and Environmental Sciences, The George Washington University, 2029 G Street N.W., Washington, D.C. 20006
| | - Stephen F. Wolf
- Department of Chemistry, Wetherill Laboratory, 560 Oval Drive, Purdue University, West Lafayette, Indiana 47907-2038, Department of Chemistry, Indiana State University, Terre Haute, Indiana 47809-5901, and Department of Earth and Environmental Sciences, The George Washington University, 2029 G Street N.W., Washington, D.C. 20006
| | - John M. Hanchar
- Department of Chemistry, Wetherill Laboratory, 560 Oval Drive, Purdue University, West Lafayette, Indiana 47907-2038, Department of Chemistry, Indiana State University, Terre Haute, Indiana 47809-5901, and Department of Earth and Environmental Sciences, The George Washington University, 2029 G Street N.W., Washington, D.C. 20006
| | - F. Bartow Culp
- Department of Chemistry, Wetherill Laboratory, 560 Oval Drive, Purdue University, West Lafayette, Indiana 47907-2038, Department of Chemistry, Indiana State University, Terre Haute, Indiana 47809-5901, and Department of Earth and Environmental Sciences, The George Washington University, 2029 G Street N.W., Washington, D.C. 20006
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Current literature in mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2001; 36:446-457. [PMID: 11333450 DOI: 10.1002/jms.91] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Grassineau NV, Nisbet EG, Bickle MJ, Fowler CM, Lowry D, Mattey DP, Abell P, Martin A. Antiquity of the biological sulphur cycle: evidence from sulphur and carbon isotopes in 2700 million-year-old rocks of the Belingwe Belt, Zimbabwe. Proc Biol Sci 2001; 268:113-9. [PMID: 11209879 PMCID: PMC1088579 DOI: 10.1098/rspb.2000.1338] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Sulphur and carbon isotopic analyses on small samples of kerogens and sulphide minerals from biogenic and non-biogenic sediments of the 2.7 x 10(9) years(Ga)-old Belingwe Greenstone Belt (Zimbabwe) imply that a complex biological sulphur cycle was in operation. Sulphur isotopic compositions display a wider range of biological fractionation than hitherto reported from the Archaean. Carbon isotopic values in kerogen record fractionations characteristic of rubisco activity methanogenesis and methylotrophy and possibly anoxygenic photosynthesis. Carbon and sulphur isotopic fractionations have been interpreted in terms of metabolic processes in 2.7 Ga prokaryote mat communities, and indicate the operation of a diverse array of metabolic processes. The results are consistent with models of early molecular evolution derived from ribosomal RNA.
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Affiliation(s)
- N V Grassineau
- Department of Geology, Royal Holloway, University of London, Surrey, UK.
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