Positive Sulfate Sulfur Isotope Excursion Indicates Large-Scale Pyrite Burial and Marine Anoxia during the End–Triassic Mass Extinction

The late Rhaetian–early Hettangian transition is characterised by the emplacement of Central Atlantic magmatic province and associated climatic effects, coincident with a severe biotic crisis (~201.5 Ma). The oxygen deficiency in the ocean realm is possibly linked to this significant loss in marine biodiversity. However, direct evidence of contemporaneous development of marine anoxia on a global scale has been lacking and the relationship between oxygen and extinction is unclear. Here we report carbonate-associated sulfate δ34S data from three sections across the Late Triassic–Early Jurassic transition. We find synchronous large positive δ34S shifts with a magnitude of >10‰ in the latest…