Assessment of the natural variability of B, Cd, Cu, Fe, Pb, Sr, Tl and Zn concentrations and isotopic compositions in leaves, needles and mushrooms using single sample digestion and two-column matrix separation

Carbon isotopes in Neogene-age fossil teeth and paleosol carbonates are commonly interpreted in the context of past distributions of C3 and C4 vegetation. These two plant types have very different distributions in relation to climate and ecology, and provide a robust basis for reconstructing terrestrial paleoclimates and paleoenvironments during the Neogene. Carbon isotopes in pre-Neogene fossil teeth are usually interpreted in the context of changes in the δ13C value of atmospheric CO2, and variable climate-dependent carbon-isotope discrimination in C3 plants. Carbon isotopes in pre-Neogene soil carbonates can be used to estimate past levels of atmospheric CO2. Oxygen isotopes in fossil teeth and paleosol carbonates primarily are influenced by the oxygen isotopic compositions of ancient rainfall and surface waters. The oxygen isotopic composition of rainfall is has a complex, but tractable, relationship with climate, and variably relates to temperature, elevation, precipitation amount, and other factors. Mammal species that rely on moisture in dietary plant tissues to satisfy their water requirements (rather than surface drinking water) may have oxygen isotopic compositions that track aridity. Thus, oxygen isotopes of fossil mammals can place broad constraints on paleoaridity. Carbonate clumped isotope thermometry allows for reconstruction of soil temperatures at the time of pedogenic carbonate mineralization. The method is unique because it is the only thermodynamically based isotopic paleothermometer that does not require assumptions about the isotopic composition of the fluid in which the archive mineral formed. Soil temperature reflects a complex interplay of air temperature, solar radiative heating, latent heat effects, soil thermal diffusivity, and seasonal variations of these parameters. Because plants and most animals live in and/or near the soil, soil temperature is an important aspect of terrestrial (paleo)climate.

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Status-quo of carbonate cadmium isotope compositions as a paleo-productivity proxy

10.5194/egusphere-egu21-825 ◽

2021 ◽

Author(s):

Simon V. Hohl

Keyword(s):

Isotopic Composition ◽

Isotope Composition ◽

Status Quo ◽

Ambient Seawater ◽

Isotopic Compositions ◽

Marine Carbonates ◽

The Status ◽

State Changes ◽

Underlying Processes ◽

Isotope Systematics

Cadmium (Cd) and isotope systematics are emerging tools for studying the biogeochemical cycling of micronutrients in the oceans, and sedimentary archives, as Cd concentrations in seawater show a nutrient-like behaviour, with surface depletion and deep water enrichments. However, the underlying processes are yet to be fully understood. The Cd concentration and isotopic composition of seawater are set by the balance of Cd inputs (and their isotopic composition) and the fractionation on removal to sedimentary sinks. The most favoured explanation is the Cd utilisation by marine phototrophic biomass, causing the surface water&#8217;s dissolved Cd pool depletion creating a depth gradient of increasing Cd concentrations and lighter isotopic compositions. Under incomplete oxidative recycling, organic matter may act as an effective Cd sink and authigenic minerals may store the ambient seawater&#8217;s Cd isotope composition.Consequently, stable Cd isotope compositions in marine carbonates show broad variations linked to paleo-productivity and redox state changes. Additional fractionation processes govern the Cd isotopic compositions of marine sediments. Besides biological utilisation, experimental Cd partitioning into authigenic calcites or sulphides under variable redox and salinity conditions has been shown. &#160;Therefore, when applying Cd isotopes in carbonates, other geochemical proxies must be evaluated very carefully to understand the involved Cd fractionation processes. This presentation aims to present the status quo of research done on authigenic and biologic carbonates and carbonate leachates in carbonatic shales to show the strengths and pitfalls of this new emerging bio-geoscience isotope proxy and its use for paleoenvironmental reconstructions on Earth and beyond.&#160;&#160;

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The chlorine-isotopic composition of lunar KREEP from magnesian-suite troctolite 76535

American Mineralogist ◽

10.2138/am-2020-7467 ◽

2020 ◽

Vol 105 (8) ◽

pp. 1270-1274

Author(s):

Francis M. McCubbin ◽

Jessica J. Barnes

Keyword(s):

Isotopic Composition ◽

Melt Inclusions ◽

Melt Inclusion ◽

Isotopic Fractionation ◽

Magma Ocean ◽

Geochemical Composition ◽

Isotopic Compositions ◽

Stable Isotopic ◽

Lunar Samples

Abstract We conducted in situ Cl isotopic measurements of apatite within intercumulus regions and within a holocrystalline olivine-hosted melt inclusion in magnesian-suite troctolite 76535 from Apollo 17. These data were collected to place constraints on the Cl-isotopic composition of the last liquid to crystallize from the lunar magma ocean (i.e., urKREEP, named after its enrichments in incompatible lithophile trace elements like potassium, rare earth elements, and phosphorus). The apatite in the olivine-hosted melt inclusion and within the intercumulus regions of the sample yielded Cl-isotopic compositions of 28.3 ± 0.9‰ (2σ) and 30.3 ± 1.1‰ (2σ), respectively. The concordance of these values from both textural regimes we analyzed indicates that the Cl-isotopic composition of apatites in 76535 likely represents the Cl-isotopic composition of the KREEP-rich magnesian-suite magmas. Based on the age of 76535, these results imply that the KREEP reservoir attained a Cl-isotopic composition of 28–30‰ by at least 4.31 Ga, consistent with the onset of Cl-isotopic fractionation at the time of lunar magma ocean crystallization or shortly thereafter. Moreover, lunar samples that yield Cl-isotopic compositions higher than the value for KREEP are likely affected by secondary processes such as impacts and/or magmatic degassing. The presence of KREEP-rich olivine-hosted melt inclusions within one of the most pristine and ancient KREEP-rich rocks from the Moon provides a new opportunity to characterize the geochemistry of KREEP. In particular, a broader analysis of stable isotopic compositions of highly and moderately volatile elements could provide an unprecedented advancement in our characterization of the geochemical composition of the KREEP reservoir and of volatile-depletion processes during magma ocean crystallization, more broadly.

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Isotopic compositions of the elements 2013 (IUPAC Technical Report)

Pure and Applied Chemistry ◽

10.1515/pac-2015-0503 ◽

2016 ◽

Vol 88 (3) ◽

pp. 293-306 ◽

Cited By ~ 282

Author(s):

Juris Meija ◽

Tyler B. Coplen ◽

Michael Berglund ◽

Willi A. Brand ◽

Paul De Bièvre ◽

...

Keyword(s):

Critical Evaluation ◽

Single Sample ◽

International Union ◽

Applied Chemistry ◽

Isotopic Compositions ◽

Technical Report ◽

Isotopic Abundances

AbstractThe Commission on Isotopic Abundances and Atomic Weights (ciaaw.org) of the International Union of Pure and Applied Chemistry (iupac.org) has revised the Table of Isotopic Compositions of the Elements (TICE). The update involved a critical evaluation of the recent published literature. The new TICE 2013 includes evaluated data from the “best measurement” of the isotopic abundances in a single sample, along with a set of representative isotopic abundances and uncertainties that accommodate known variations in normal terrestrial materials.

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Gypsum speleothems record the triple oxygen (δ17O and δ18O) and hydrogen (δ2H) isotopic composition of cave dripwater: potential paleoenvironmental implications

10.5194/egusphere-egu2020-6938 ◽

2020 ◽

Author(s):

Fernando Gazquez ◽

Veronica Chiarini ◽

Andrea Columbu ◽

Jo De Waele ◽

Philippe Audra ◽

...

Keyword(s):

Isotopic Composition ◽

Ostwald Ripening ◽

Environmental Parameters ◽

Effect Of Temperature ◽

Seepage Water ◽

Isotopic Compositions ◽

Ne Italy ◽

Show Evidence ◽

Interface Science ◽

Entire Dataset

Gypsum (CaSO4&#8729;2H2O) speleothems (i.e. stalactites, stalagmites, etc.) in caves form frequently through dissolution of the gypsum host-rock by seepage water and subsequent secondary mineral re-precipitation from gypsum-saturated solutions [1]. Gypsum takes its structurally-bound hydration water (GHW) from the liquid; the isotopic composition (&#948;17O, &#948;18O and &#948;2H) of GHW reflects that of cave dripwater at the time of mineral crystallization, with insignificant effect of temperature on the liquid-GHW isotope fractionation factors [2]; therefore, GHW may be used to reconstruct the isotopic composition of paleo-dripwater in caves. Here we investigate the triple oxygen and hydrogen isotopic composition of GHW in speleothems from circum-Mediterranean gypsum caves, including the gypsum karsts of Emilia Romagna (NE Italy), Sorbas (SE Spain), Sicily and Mesaoria (Cyprus), all of them hosted in gypsum of Messinian age (ca. 5.5 Ma). The climatic settings of the studied caves range from semiarid (i.e. Sorbas and Mesaoria, <300 mm&#183;yr-1) to relatively wet (i.e. Emilia Romagna and Sicily >600 mm&#183;yr-1).Our results reveal that most gypsum speleothems in these caves precipitated from unevaporated solutions (e.g. d-excess >8&#8240; and 17Oexcess >10 per meg), with isotopic compositions similar to those of local meteoric/seepage waters and close to the local meteoric water lines (LMWL) of each region. Gypsum crystallization in absence of evaporation can be explained by the mechanism known as Ostwald ripening [3], a solution-mediated recrystallization under constant temperature by which older crystals (i.e. Messinian gypsum) dissolve to feed new crystals (i.e. gypsum speleothems). Only GHW in speleothems from the Sorbas caves show evidence for solution evaporation prior mineral precipitation. Gypsum speleothems in several caves of Emilia Romagna crystallized from unevaporated waters with significantly different triple oxygen and hydrogen isotopic compositions (e.g. Ca&#180; Castellina cave: &#948;18O=-8.3&#177;0.3&#8240;, &#948;2H=-55.2&#177;1.7&#8240;, 17Oexcess=33&#177;9 per meg; Abisso Bentini cave: &#948;18O=-10.6&#177;0.3&#8240;, &#948;2H=-73.4&#177;1.8&#8240;, 17Oexcess=47&#177;13 per meg). In absence of chronological data, this can be interpreted as (1) gypsum speleothems formed in different climatic periods or (2) do at present from waters that seepage into the epikarst during different times of the year. Either way, gypsum records the mean isotopic composition of seepage water under distinct environmental conditions in this region.The &#948;18O and 17Oexcess values across the entire dataset are negatively correlated, unlike &#948;18O and d-excess values that are, positively correlated for &#948;18O<-6&#8240; and negatively correlated for &#948;18O>-6&#8240;. We suggest that the different behaviors of 17Oexcess and d-excess derive from their distinct sensitivities to environmental parameters (i.e. RH and temperature) during formation of water vapor at the moisture source of rain and local effects during rainfall events in each area. We conclude that gypsum speleothems of known ages may be useful as archives for triple oxygen and hydrogen isotope reconstructions of paleo-rainfall.[1] G&#225;zquez et al. 2017. Chemical Geology, v. 452, p. 34&#8211;46; [2] G&#225;zquez et al. 2017. Geochimica et Cosmochimica Acta, v. 198, p. 259&#8211;270; [3] Kahlweit, 1975. Advances in Colloid and Interface Science, v. 5, p. 1&#8211;35.

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Developing Micro-Raman Mass Spectrometry for Measuring Carbon Isotopic Composition of Carbon Dioxide

Applied Spectroscopy ◽

10.1366/000370207781393244 ◽

2007 ◽

Vol 61 (7) ◽

pp. 701-705 ◽

Cited By ~ 18

Author(s):

Masashi Arakawa ◽

Junji Yamamoto ◽

Hiroyuki Kagi

Keyword(s):

Isotopic Composition ◽

Intensity Ratio ◽

High Spatial Resolution ◽

Carbon Isotopic Composition ◽

Peak Intensity Ratio ◽

Factors Affecting ◽

Isotopic Compositions ◽

Carbon Isotopic ◽

Peak Intensity ◽

The Relationship

We investigated the applicability of micro-Raman spectroscopy for determining carbon isotopic compositions (13C/12C) of minute CO2 fluid inclusions in minerals. This method is nondestructive and has sufficiently high spatial resolution (1 μm) to measure each fluid inclusion independently. Raman spectra of CO2 fluid have 12CO2-origin peaks at about 1285 cm−1 and 1389 cm−1 (v12− and v12+) and a 13CO2-origin peak at about 1370 cm−1 (v13+). The relationship between carbon isotopic compositions and peak intensity ratios of v12+ and v13+ was calibrated. Considering several factors affecting the peak intensity ratio, the error in obtained carbon isotopic composition was 2% (20‰). The reproducibility of the intensity ratio under the same experimental environment was 0.5% (5‰). Within these error values, we can distinguish biogenic CO2 from abiogenic CO2.

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Isotopic compositions of the elements 2009 (IUPAC Technical Report)

Pure and Applied Chemistry ◽

10.1351/pac-rep-10-06-02 ◽

2011 ◽

Vol 83 (2) ◽

pp. 397-410 ◽

Cited By ~ 559

Author(s):

Michael Berglund ◽

Michael E. Wieser

Keyword(s):

Mass Spectrometry ◽

Isotope Ratio ◽

Critical Evaluation ◽

Isotope Ratio Mass Spectrometry ◽

Atomic Weight ◽

Single Sample ◽

International Union ◽

Isotopic Compositions ◽

Technical Report ◽

Isotopic Abundances

The Commission on Isotopic Abundances and Atomic Weights (CIAAW) of the International Union of Pure and Applied Chemistry (IUPAC) completed its last update of the isotopic compositions of the elements as determined by isotope-ratio mass spectrometry in 2009. That update involved a critical evaluation of the published literature and forms the basis of the table of the isotopic compositions of the elements (TICE) presented here. For each element, TICE includes evaluated data from the “best measurement” of the isotope abundances in a single sample, along with a set of representative isotope abundances and uncertainties that accommodate known variations in normal terrestrial materials. The representative isotope abundances and uncertainties generally are consistent with the standard atomic weight of the element Ar(E) and its uncertainty U[Ar(E)] recommended by CIAAW in 2007.

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Also tropical freshwater ostracods show a seasonal life cycle

10.5194/bg-2017-38 ◽

2017 ◽

Author(s):

Juliane Meyer ◽

Claudia Wrozyna ◽

Albrecht Leis ◽

Werner Piller

Keyword(s):

Life Cycle ◽

Environmental Factors ◽

Isotopic Composition ◽

Temporal Variations ◽

South Florida ◽

Population Variation ◽

Instrumental Data ◽

Mean Values ◽

Isotopic Signatures ◽

Isotopic Compositions

Abstract. Isotopic signatures of ostracod shells became common proxies for the reconstruction of paleo-environmental conditions. Their isotopic composition is the result of the composition of their host water and the phenology and ecology of the target species. The sum of spatial and temporal variations from environmental factors in the species habitat defines the maximum isotopic variation of a population during the time of their shell formation. Here we present isotopic signatures (δ18O, δ13C) of living Cytheridella ilosvayi (Ostracoda) and chemical and isotopic compositions of 14 simultaneously sampled freshwater habitats in South Florida and instrumental data of the region. The chemical and isotopic compositions of the selected sites characterize the different habitats and show the influence of the source water, biological activity and the duration of exposure to the surface. Isotopic signatures of C. ilosvayi shells correlate well with the isotopic composition of their host waters. Within-sample variability of repeated isotopic measurements of ostracod shells reflect habitat dependent ranges and indicate temperature and the δ18O composition of precipitation (δ18Oprec) as regional environmental factors responsible for the population variation. Instrumental data of water temperature and δ18Oprec were used to calculate the monthly variation of a theoretical calcite in rivers of Florida showing distinct seasonal variations in values and ranges. Different configurations of the theoretical calcite were compared to the within-sample variability to identify possible calcification periods of C. ilosvayi. For a plausible calcification period the ostracod isotopic range has to correlate with mean values of the theoretical calcite with a slight positive offset (vital effect) and the extension of the theoretical calcite range. The tested model suggests a seasonal calcification period of C. ilosvayi in early spring. The surprising seasonality of a tropical ostracod life cycle is probably coupled to the hydrologic cycle of Florida. The results of this study contribute to the application of ostracod isotopes in modern calibration studies and their potential use in paleontology.

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Oxygen and Hydrogen isotopic composition of tap waters in France

Geological Society London Special Publications ◽

10.1144/sp507-2020-207 ◽

2021 ◽

pp. SP507-2020-207

Author(s):

V. Daux ◽

B. Minster ◽

A. Cauquoin ◽

O. Jossoud ◽

M. Werner ◽

...

Keyword(s):

Isotopic Composition ◽

Geographical Origin ◽

Atlantic Coast ◽

Regional Scale ◽

Content Type ◽

Isotopic Compositions ◽

Manufactured Products ◽

The Alps ◽

Supplementary Material ◽

Hydrogen Isotopic Composition

AbstractThe isotopic composition of oxygen (δ18O), and hydrogen (δ2H) are widely used to locate the geographical origin of biological remains or manufactured products. In this paper, we analyze the distributions of δ18O and δ2H in tap waters sampled across France, and in precipitation interpolated with OIPC and modelled with the isotope-enabled ECHAM6-wiso model. Our aim is to provide isoscapes usable in archaeology and forensics and evaluate if modelled data could be surrogates for measured ones.The δ18O and δ2H in the 396 tap waters sampled vary spatially within a range of 10‰ and 77‰ respectively. Their consistent distributions follow rules summarized by the effects of altitude and distance from the coast. Their variations along the year are small. Therefore, the database provides a solid reference for δ18O and δ2H of the water supply system at the regional scale. The areas with the most uncommon oxygen and hydrogen isotopic compositions (Atlantic coast South of Brittany and the highest elevations in the Alps) are the most accurately traceable areas in provenancing studies.The isotopic compositions of modelled precipitation have the same spatial distributions but different absolute values from those of tap waters. Therefore, our results favour the use of statistical isoscapes rather than GCM-based isoscapes in provenancing studies.Supplementary material at https://doi.org/10.6084/m9.figshare.c.5256034

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Earth’s water may have been inherited from material similar to enstatite chondrite meteorites

Science ◽

10.1126/science.aba1948 ◽

2020 ◽

Vol 369 (6507) ◽

pp. 1110-1113 ◽

Cited By ~ 5

Author(s):

Laurette Piani ◽

Yves Marrocchi ◽

Thomas Rigaudier ◽

Lionel G. Vacher ◽

Dorian Thomassin ◽

...

Keyword(s):

Solar System ◽

Isotopic Composition ◽

Carbonaceous Chondrite ◽

Earth’S Crust ◽

Outer Solar System ◽

Volatile Elements ◽

Earth’S Mantle ◽

Isotopic Compositions ◽

Enstatite Chondrite ◽

Earth's Crust

The origin of Earth’s water remains unknown. Enstatite chondrite (EC) meteorites have similar isotopic composition to terrestrial rocks and thus may be representative of the material that formed Earth. ECs are presumed to be devoid of water because they formed in the inner Solar System. Earth’s water is therefore generally attributed to the late addition of a small fraction of hydrated materials, such as carbonaceous chondrite meteorites, which originated in the outer Solar System where water was more abundant. We show that EC meteorites contain sufficient hydrogen to have delivered to Earth at least three times the mass of water in its oceans. EC hydrogen and nitrogen isotopic compositions match those of Earth’s mantle, so EC-like asteroids might have contributed these volatile elements to Earth’s crust and mantle.

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