biostudies-literatureRigo MItalian MURItalian MUR (Ministero dell'Università e della Ricerca)Japan Society for the Promotion of Science15574https://www.ebi.ac.uk/biostudies/studies/S-EPMC11227520biostudies-literatureUnknown14(1)The latest Triassic was characterised by protracted biotic extinctions concluding in the End-Triassic Extinction (~ 200 Ma) and a global carbon cycle perturbation. The onset of declining diversity is closely related to reducing conditions that spread globally from upper Sevatian (uppermost Norian) to across the Norian-Rhaetian boundary, likely triggered by unusually high volcanic activity. We correlate significant organic carbon cycle perturbations to an increase of CO₂ in the ocean-atmosphere system, likely outgassed by the Angayucham igneous province, the onset of which is indicated by the initiation of a rapid decline in ⁸⁷Sr/⁸⁶Sr and ¹⁸⁸Os/¹⁸⁷Os seawater values. A possible causal mechanism involves elevated CO₂ levels caScientific reportsUnveiling a new oceanic anoxic event at the Norian/Rhaetian boundary (Late Triassic).PMC11227520JP20K0411316KK0104PRIN 2017W2MARECardinali AOnoue TJin XTomimatsu YWu QKatz MERigo MMaron MDu YBertinelli Avan Wieren CSSatolli STackett LSCampbell HLei JZXZaffani MConcheri GGodfrey LSato HfalseUnveiling a new oceanic anoxic event at the Norian/Rhaetian boundary (Late Triassic).The latest Triassic was characterised by protracted biotic extinctions concluding in the End-Triassic Extinction (~ 200 Ma) and a global carbon cycle perturbation. The onset of declining diversity is closely related to reducing conditions that spread globally from upper Sevatian (uppermost Norian) to across the Norian-Rhaetian boundary, likely triggered by unusually high volcanic activity. We correlate significant organic carbon cycle perturbations to an increase of CO₂ in the ocean-atmosphere system, likely outgassed by the Angayucham igneous province, the onset of which is indicated by the initiation of a rapid decline in ⁸⁷Sr/⁸⁶Sr and ¹⁸⁸Os/¹⁸⁷Os seawater values. A possible causal mechanism involves elevated CO₂ levels ca2024-01-01T00:00:00Z2024 Jul2025-04-22T15:31:30.127Z2025-04-06T01:26:14.96ZS-EPMC112275203897186710.1038/s41598-024-66343-z