Sedimentary sulfur isotopes and Neoarchean ocean oxygenation.

ABSTRACT: Abrupt disappearance of mass-independent fractionation of sulfur isotopes (MIF-S) from the geologic record and an apparent ingrowth in seawater sulfate around 2.45 billion years ago (Ga) signal the first large-scale oxygenation of the atmosphere [the Great Oxygenation Event (GOE)]. Pre-GOE O₂ production is evident from multiple other terrestrial and marine proxies, but oceanic O₂ concentrations remain poorly constrained. Furthermore, current interpretations of S isotope records do not explain a concurrent expansion in the range of both MIF-S-diagnostic for low atmospheric O₂-and δ³⁴S beginning at 2.7 Ga. To address these unknowns, we developed a reaction-transport model to analyze the preservation patterns of sulfur isotopes in Archean sedimentar

SUBMITTER: Fakhraee M 

PROVIDER: S-EPMC5783677 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature