title: Multiple S-isotopic evidence for episodic shoaling of anoxic water during Late Permian mass extinction.
abstract: Global fossil data show that profound biodiversity loss preceded the final catastrophe that killed nearly 90% marine species on a global scale at the end of the Permian. Many hypotheses have been proposed to explain this extinction and yet still remain greatly debated. Here, we report analyses of all four sulphur isotopes ((32)S, (33)S, (34)S and (36)S) for pyrites in sedimentary rocks from the Meishan section in South China. We observe a sulphur isotope signal (negative δ(34)S with negative Δ(33)S) that may have resulted from limitation of sulphate supply, which may be linked to a near shutdown of bioturbation during shoaling of anoxic water. These results indicate that episodic shoaling of anoxic water may have contributed to the profound biodiversity crisis before the final catastrophe. Our data suggest a prolonged deterioration of oceanic environments during the Late Permian mass extinction.
authors.affiliation: CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China. yashen@ustc.edu.cn
authors.forename: Yanan
authors.initials: Y
authors.lastname: Shen
authors.forename: James
authors.initials: J
authors.lastname: Farquhar
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Andrew
authors.initials: A
authors.lastname: Masterson
authors.forename: Tonggang
authors.initials: T
authors.lastname: Zhang
authors.forename: Boswell A
authors.initials: BA
authors.lastname: Wing
mesh_terms: D000818:Animals; D002681:China; D053476:Extinction, Biological; D005580:Fossils; D019015:Geologic Sediments / Q000737:chemistry*; D007501:Iron / Q000032:analysis*; D013440:Sulfides / Q000032:analysis*; D013455:Sulfur / Q000032:analysis*; D013460:Sulfur Isotopes / Q000032:analysis*; D014872:Water Movements
chemical_list: D013440:Sulfides; D013460:Sulfur Isotopes; C011342:pyrite; D013455:Sulfur; D007501:Iron