Identification of sulfate in natural carbonates by x-ray absorption spectroscopy

Pingitore, Nicholas E.; Meitzner, G.; Love, Karen M.

doi:10.1016/0016-7037(95)00142-5

Cited by 103 publications

(64 citation statements)

References 23 publications

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“…The Na-S-Mg correlations can be related to the fact that ~40-60% of SO 4 2-in seawater is ion paired with Na + and Mg 2+ (i.e., NaSO 4 -and MgSO 4 0 ) (e.g., Byrne, 2002); therefore, we suggest that these ion pairs as well as Na + , Mg 2+ and SO 4 2-may be incorporated into any type of marine aragonite. Pingitore et al (1995) showed, by X-ray absorption spectroscopy, that S exists as SO 4 2-in coral skeletons. It is still unclear whether Na + , Mg 2+ and SO 4 2-can occupy specific sites in the crystal lattices of biogenic and abiogenic marine aragonites.…”

Section: Indicate Results Of 5 Coral Powder Samples (Shown As Differementioning

confidence: 99%

Na/Ca variability in coral skeletons

2010

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Section: Indicate Results Of 5 Coral Powder Samples (Shown As Differementioning

confidence: 99%

Na/Ca variability in coral skeletons

2010

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“…Sulfate is structurally substituted into the carbonate lattice during carbonate precipitation, and the concentration of CAS is proportional to ambient sulfate concentrations during carbonate precipitation (20,34). How CAS concentration specifically scales with seawater sulfate concentration is not well-known and can be influenced by a number of factors (e.g., temperature, mineralogy, and crystal growth rate).…”

Section: Diagenetic Influence On Carbonate Precipitationmentioning

confidence: 99%

“…Carbon isotope values of DIC show an initial decrease with depth linked to remineralization of 12 C-enriched organic matter with a variety of oxidants (oxygen, Mn 4þ , Fe 3þ , nitrate, and sulfate) and then shift to markedly positive values in the methanic zone, where 12 C from organic matter is preferentially incorporated into methane (19). Sulfate is structurally substituted into the carbonate lattice during carbonate precipitation (20), and therefore carbonateassociated sulfate (CAS) incorporated during precipitation in the methanic zone should have extremely positive δ 34 S values. Further, because sulfate must be essentially depleted before the onset of appreciable methanogenesis, CAS concentrations in methanic carbonates should be very low.…”

mentioning

confidence: 99%

Sulfur record of rising and falling marine oxygen and sulfate levels during the Lomagundi event

Planavsky

Bekker

Hofmann

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

183

130

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Carbonates from approximately 2.3-2.1 billion years ago show markedly positive δ 13 C values commonly reaching and sometimes exceeding þ10‰. Traditional interpretation of these positive δ 13 C values favors greatly enhanced organic carbon burial on a global scale, although other researchers have invoked widespread methanogenesis within the sediments. To resolve between these competing models and, more generally, among the mechanisms behind Earth's most dramatic carbon isotope event, we obtained coupled stable isotope data for carbonate carbon and carbonate-associated sulfate (CAS). CAS from the Lomagundi interval shows a narrow range of δ 34 S values and concentrations much like those of Phanerozoic and modern marine carbonate rocks. The δ 34 S values are a close match to those of coeval sulfate evaporites and likely reflect seawater composition. These observations are inconsistent with the idea of diagenetic carbonate formation in the methanic zone. Toward the end of the carbon isotope excursion there is an increase in the δ 34 S values of CAS. We propose that these trends in C and S isotope values track the isotopic evolution of seawater sulfate and reflect an increase in pyrite burial and a crash in the marine sulfate reservoir during ocean deoxygenation in the waning stages of the positive carbon isotope excursion.Lomagundi excursion | Great Oxidation Event | Precambrian

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“…Sulfur and magnesium K-edge X-ray absorption near edge structure (XANES) has also been applied to the characterization of the chemical environment (e.g., Pingitore et al, 1995;Morra et al, 1997;Finch and Allison, 2008;Foster et al, 2008;Cusack et al, 2008;Yoshimura et al, 2013a). XAS can be used in combination with X-ray fluorescence with a focused X-ray beam (i.e., micro-X-ray fluorescence; µ-XRF) to determine the speciation-specific spatial element distribution in biogenic carbonates and to generate time series of trace-element profiles in biogenic CaCO 3 with high lateral resolution.…”

Section: T Yoshimura Et Al: Fluctuations Of Sulfate S-bearing Aminmentioning

confidence: 99%

Fluctuations of sulfate, S-bearing amino acids and magnesium in a giant clam shell

et al. 2014

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Abstract. We used micro-X-ray fluorescence combined with X-ray photoabsorption spectroscopy to investigate speciation-specific sulfur profiles in the inner shell layer of a giant clam (Hippopus hippopus). The sulfate, S-bearing amino acids, and total sulfur profiles indicated that inorganic sulfate was the dominant component in the shell of this bivalve. Sulfur profiles in the inner shell layer showed clear annual fluctuations that varied by more than one order of magnitude, from < 50 to 1420 ppm, and sulfate and total sulfur maxima became higher with age, whereas no ontogenetic trend was noticeable in the profile of S-bearing amino acids. A change in the carbonate ion concentration in the calcifying fluid would suggest that an ontogenetic increase in the relative activity of sulfate ions to carbonate ions in the calcifying fluid affects sulfate concentrations in the shells. These results suggest that trace sulfur profiles in the shell of the giant clam may reflect both cyclic shell growth related to environmental factors such as insolation and temperature and ontogenetic changes of the calcifying fluid chemistry mediated by physiological processes. The observed S profile implies a clear change in calcifying fluid chemistry towards less alkaline condition with age. Magnesium fluctuations suggested that Mg was incorporated into the shells at high growth rates during warm seasons. The spectrum of Mg K-edge X-ray absorption near edge structure (XANES) and comparison of Mg and S-bearing amino acids profiles indicated that a pronounced effect of the organic fraction or disordered phases were observed in aragonitic shell of H. hippopus rather than regulated substitution into the aragonite crystal lattice.

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Identification of sulfate in natural carbonates by x-ray absorption spectroscopy

Cited by 103 publications

References 23 publications

Na/Ca variability in coral skeletons

Na/Ca variability in coral skeletons

Sulfur record of rising and falling marine oxygen and sulfate levels during the Lomagundi event

Fluctuations of sulfate, S-bearing amino acids and magnesium in a giant clam shell

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