δ34S character of organosulfur compounds in kerogen and bitumen fractions of sedimentary rocks

Abstract

and bitumen fractions is likely reflective of differences in timing of production, reduced sulfur sources or organic sulfurisation mechanism.

Stable Isotope Geochemistry of the Organic Elements within Shales and Crude Oils: A Comprehensive Review

“…Amrani et al [ 64 ] proposed a method for analyzing individual sulfur organic compounds using a gas chromatography–multi-collector–inductively coupled mass spectrometer (GC-MC-ICP-MS). Sample sizes are at orders of magnitude smaller than what is commonly used for SO 2 and SF6 [ 84 ] due to poor detection limits. The GC-MC-ICP-MS method does not require any chemical preparation and allows for simultaneous collection of all four sulfur isotopes; however, it has lesser precision than other methods.…”

The application of compound-specific sulfur isotopes to the oil–source rock correlation of Kurdistan petroleum

“…This leads to residual kerogen being slightly enriched in S from which oil was subsequently expelled at higher maturity. Alternatively, 34 S depleted H 2 S might be formed via the secondary cracking of higher MW OSCs in the bitumen, as was suggested to account for 34 S enriched OSCs produced by the hydrogen pyrolysis (HyPy) treatment of several S-rich kerogens (Grotheer et al, 2017). S isotopic trends evident from a simulated thermal maturity study of Type II-S source rocks (Rosenberg et al, 2017) included the evolution of H 2 S that was a few ‰ depleted in  34 S than the immature kerogen, consistent with a kinetic control favouring release of 32 S, although the residual kerogen and oil released showed only a minor 34 S enrichment ( 34 S increase of +0.4‰).…”

Precambrian Organic Matter

“…Further discoveries of taxonomically informative organic-walled microscopic and macroscopic fossils and of indigenous and diagnostic molecular fossils (Schinteie and Brocks 2017) can be used to improve phylogenies derived from the DNA of contemporary organisms (Dacks et al 2016), to calibrate and test molecular clocks (Gold et al 2017), and overall, to provide further insight into the emergence and diversification of complex life on the Earth (Knoll and Nowak 2017). Last, but not least, the ability to measure the isotopic compositions of multiple elements in the same sample of organic matter, or even the same microscopic fossil, opens new windows into the microbial physiologies and the evolution of Precambrian biogeochemical cycles (Ader et al 2016;Grotheer et al 2017;House et al 2000;Sessions 2016;Stüeken et al 2016;Williford et al 2015).…”