Sedimentary organic matter, sulfur

Pyrite is a major sink for reduced sulfur from the JH S/S0/]- system to the extent that reactive iron is available. In sediments with limited amounts of reactive iron, reduced sulfur species in the H2S/S°/H2SX system are available for reaction with the sedimentary organic matter. 

They suggested that this could be a major pathway for the incorporation of sulfur into sedimentary organic matter during early diagenesis. 

Table IV. Relative importance of abundances of dissolved sulfate (S042-), sedimentary organic matter (OM), and sedimentary iron (Fe) in controlling the sulfur geochemistry in Flodelle Creek (FC), Great Lakes (GL), Walker Lake (WL), Great Salt Lake (GSL), Soap Lake (SL) sediments and Green River (GRF) and Rundle (RF) Formations. XXX, greatest X, least...

Environmental conditions are usually considered to be the main factors controlling for sulfur content of sedimentary organic matter (1). The favourable sedimentary conditions proposed for incorporation of sulfur into organic matter include organic matter richness, anaerobic conditions, and iron depleted environments. Under anaerobic conditions, if sulfate is available, bacterial sulfate-reduction is promoted and the resulting inorganic sulfur species are able to react with and become incorporated into organic matter. 

Characterization of Organically Bound Sulfur in High-Molecular-Weight, Sedimentary Organic Matter Using Flash Pyrolysis and Raney Ni Desulfurization... 

Relationship between Molecular Weight and Organic Sulfur in Sulfur-Rich Sedimentary Organic Matter... 

Figure 14. Relationship between the degree of intermolecular versus intramolecular sulfur cross-linking and molecular weight for sulfur-rich sedimentary organic matter.

Note. Organic Sulfur in Macromolecular Sedimentary Organic Matter, Part IV 4Current address Fye Laboratory, Department of Chemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543... 

One of the main reasons for the recent interest in organic sulfur in sedimentary organic matter is the growing evidence that it plays a role in the petroleum generation process. Organically-bound sulfur has been implicated in the formation of low API gravity, asphaltene-rich petroleums at a low level of thermal exposure (1). Recent studies indicate that... 

This view of the likely acids involved in creating Precambrian soils on Earth is supported by the isotopic composition of carbon, nitrogen, and sulfur in sedimentary organic matter, carbonates, sulfates, and sulfides, which are surprisingly similar to their modem counterparts back to 3,500 Ma, and unlike meteoritic or mantle values (Schidlowski et al, 1983 Des Marais, 1997 Canfield and Teske, 1996). 

In the environment. More generally, the results imply that a major chemical pathway for the Incorporation of sulfur into organic geopolymers is by reaction of HS with reactive sites, e.g. oleflnlc double bonds, displaceable halogens (39). within sedimentary organic matter. The Michael addition reaction of HS to acrylic acid may be used as a model case of such interactions. 

Significance of and evaluation of its imprint on sedimentary organic matter I. The role of reduced sulfur species in the diagenetic stage A conceptual review... 

Aizenshtat Z., Krein E. B., Vairavamurthy M. A. A. and Goldstein T. P. (1995) Role of sulfur in the transformations of sedimentary organic matter a mechanistic overview. In Geochemical Transformation of Sedimentary Sulfur (eds. M. A A. Vairavamurthy and A. Schoonen), pp. 16-39 American Chemical Society Symposium Series 612. 

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