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Sediments sulfur isotopes

Bruchert V, Knoblauch C, Jorgensen BB (2001) Controls on stable sulfur isotope fractionation during bacterial sulfate reduction in Arctic sediments. Geochim Cosmochim Acta 65 763-776 Bryan BA, Shearer G, Skeeters JL, Kohl DH (1983) Variable expression of the nitrogen isotope effect associated with denitrification of nitrate. J Biol Chem 258 8613-8617 Canfield DE (2001) Biogeochemistry of sulfur isotopes. Rev Mineral Geochem 43 607-636 Chau YK, Riley JP (1965) The determination of selenium in sea water, silicates, and marine organisms. Anal Chim Acta 33 36-49... [Pg.314]

Habicht KS, Canfield DE (1997) Sulfur isotope fractionation during bacterial sulfate reduction in organic-rich sediments. Geochim CosmochimActa61(24) 5351-5361 Habicht KS, Gade M, Thamdrup B, Berg P, Canfield DE (2002) Calibration of sulfate levels in the Archean ocean. Science 298 2372-2374... [Pg.315]

Frankenberger Jr. WT, Engberg RA (eds), Marcel Dekker, New York, p 281-296 Lyons TW (1997) Sulfur isotopic trends and pathways of iron sulfide formation in upper Holocene sediments of the anoxic Black Sea. Geochim Cosmochim Acta 61(16) 3367-3382... [Pg.315]

Jones HD, Kesler SE, Furman FC, Kyle JR (1996) Sulfur isotope geochemistry of southern Appalachian Mississippi Valley-type depopsits. Econ Geol 91 355-367 Jprgensen BB, BOttcher MA, Lflschen H, Neretin LN, Volkov 11 (2004) Anaerobic methane oxidation and a deep H2S sink generate isotopically heavy sulfides in Black Sea sediments. Geochim Cosmochim Acta 68 2095-2118... [Pg.251]

Rouxel O, Galy A, Elderfield H (2006) Germanium isotope variations in igneous rocks and marine sediments. Geochim Cosmochim Acta 70 3387-3400 Rouxel O, Ono S, Alt J, Rumble D, Ludden J (2008) Sulfur isotope evidence for microbial sulfate reduction in altered oceanic basalts at ODP Site 801. Earth Planet Sd Lett 268 110-123 Rozanski K, Sonntag C (1982) Vertical distribution of deuterium in atmospheric water vapour. Tellus 34 135-141... [Pg.266]

Rudnicki MD, Elderfield H, Spiro B (2001) Fractionation of sulfur isotopes during bacterial sulfate reduction in deep ocean sediments at elevated temperatures. Geochim Cosmochim Acta 65 777-789... [Pg.266]

Sulfur isotopes also show mass-independent effects that are probably produced by the same photochemical mechanism as oxygen effects in the Earth s upper atmosphere. Mass independent variations in sulfur from Martian meteorites have been interpreted to result from volcanic injections of SO2 and H2S into the Martian atmosphere followed by photolysis, which fractionates the sulfur isotopes. There is also evidence from ancient terrestrial sediments that the same photo lytic process was operating on sulfur in the Earth s atmosphere prior to 2.4 Ga, before oxygen began to accumulate in the atmosphere (see review by Thiemens, 2006). [Pg.224]

These examples convincingly demonstrate that specific OSC are formed during the early stages of diagenesis by reactions of reduced sulfur species with specific biogenic substrates. The reactive substrates are proposed to contain either carbon-carbon double bonds or other reactive functional groups that react with either hydrogen sulfide or polysulfides to form the OSC (88). These views are consistent with evidence from sulfur isotopes that H2S produced by microbial sulfate reduction is the major source of reduced sulfur in sediments... [Pg.24]

Two Type II-S kerogens (as defined by Orr (i)) from the onshore Santa Maria Basin Monterey formation were pyrolyzed in this study to determine (a) the distribution of sulfur and its isotopic composition among the various products formed during artificial maturation, and (b) maturation trends reflected in the sulfur isotopic and elemental S/C ratios of kerogens, and in the variation of C and H isotopes. In addition, S isotopes in pyrites, kerogens and bitumens from the two Monterey shale samples were examined to speculate on the mode of S incorporation into Santa Maria Basin sediments. [Pg.576]

Figure 10.12. A. Carbon isotopic composition of major groups of higher plants and autotrophic microorganisms compared with oxidized carbon (CO2, HCO3, CC>32 )- The triangles are mean values. (After Holser et al 1988 Schidlowski, 1988). B. Sulfur isotopic composition of bacteriogenic sulfide in modern marine anaerobic sediments (open bars, 1-6) and in the Permian Kupferschiefer (black bar, 7) compared with oxidized sulfate of modem (1-6) and Permian seawater (+11 %o). The black triangles are mean values. (After Holser et al., 1988.)... Figure 10.12. A. Carbon isotopic composition of major groups of higher plants and autotrophic microorganisms compared with oxidized carbon (CO2, HCO3, CC>32 )- The triangles are mean values. (After Holser et al 1988 Schidlowski, 1988). B. Sulfur isotopic composition of bacteriogenic sulfide in modern marine anaerobic sediments (open bars, 1-6) and in the Permian Kupferschiefer (black bar, 7) compared with oxidized sulfate of modem (1-6) and Permian seawater (+11 %o). The black triangles are mean values. (After Holser et al., 1988.)...
Stable sulfur isotopes can be effectively used to examine important geochemical processes associated with redox changes in sedimentary environments. For example, S042- reduction in salt marsh sediments yields isotopically depleted 534S porewater sulfide the uptake of H2S by marsh plants also results in isotopically depleted [Pg.173]

Figure 12.5 Sulfur isotopic budget based on mass isotopic fluxes (bar graphs) and their isotopic composition on a monthly basis in coastal marine sediments of cape Lookout Bight, NC (USA). Units are in mol S m-2 m-1. (Modified from Chanton and Martens, 1987b.)... Figure 12.5 Sulfur isotopic budget based on mass isotopic fluxes (bar graphs) and their isotopic composition on a monthly basis in coastal marine sediments of cape Lookout Bight, NC (USA). Units are in mol S m-2 m-1. (Modified from Chanton and Martens, 1987b.)...
Chanton, J.P., and Martens, C.S. (1987b) Biogeochemical cycling in an organic-rich coastal marine basin. 8. A sulfur isotopic budget balanced by differential diffusion across the sediment-water interface. Geochim. Cosmochim. Acta 51, 1201-1208. [Pg.561]

Jprgensen, B.B. (1979) A theoretical model of the stable sulfur isotope distribution in marine sediments. Geochim. Cosmochim. Acta 43, 363-374. [Pg.605]

The connection between weathering, evaporation, bacterial activity in marine sediments in shallow water areas and stable sulfur isotope distribution was studied by Holser and Kaplan (1966), Nielsen and Ricke (1969), Nielsen (1968), and Eremenko and Pankina (1972). The sulfur isotope ratios of evaporite sulfates show enrichment of 34S in the Devonian deposits (5 +23 °/oo), a pronounced dip in the Permian ( 5 +12 °/oo), values of +20 °/oo in the Triassic, a fall (+17 to +15 °/oo) in the Jurassic and Cretaceous, stabilizing in the Tertiary to the Recent value of +20 °/oo. [Pg.162]

Pavlov, A. A., and Kasting, J. F. (2002). Mass-independent fractionation of sulfur isotopes in archean sediments Strong evidence for an anoxic archean atmosphere. Astrobiology 2, 27—41. [Pg.1561]

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See also in sourсe #XX -- [ Pg.350 , Pg.412 ]



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