TRIASSIC TIME SCALE FROM ASTRONOMICAL-TUNED MAGNETOSTRATIGRAPHY

The majority of the Triassic stages now have a standardized magnetic polarity scale with verified astronomical-cycle durations for those polarity zones using marine and terrestrial sections. Induan Stage = 2.0 myr, with cyclo-magnetostratigraphy sections in marine South China (Meishan GSSP, Chaohu candidate for Olenekian GSSP, Xiakou) and verified in terrestrial Germanic Basin. Olenekian Stage = 3.1 myr, with cyclo-magnetostratigraphy sections in same locations, plus Olenekian-Anisian boundary cyclo-magnetostratigraphy at Guandao and Wantou (marine South China). Anisian Stage = 5.3 myr, with cyclo-magnetostratigraphy section at Guandao, and lower Anisian duplicated in Germanic Basin. Ladinian Stage = current gap in coverage. Carnian Stage = lower part spans at least 4 myr, with cyclo-magnetostratigraphy in marine South China (Wayao, Guizhou) and partial verification in Germanic Basin boreholes. Upper part = current gap in coverage. Norian Stage = either 11 myr (if using Austrian candidate for Rhaetian GSSP conodont marker) or 15 myr (if using Italian candidate for Rhaetian GSSP conodont marker); with cyclo-magnetostratigraphy from terrestrial Newark Basin (eastern USA) with verification of lower polarity pattern mainly from marine Italy and upper pattern from marine Austria. RhaetianStage = either 8 myr (if using Austrian candidate for Rhaetian GSSP conodont marker) or 4 myr (if using Italian candidate for Rhaetian GSSP conodont marker); with cycle-magnetostratigraphy from terrestrial Newark Basin with verification in terrestrial Sichuan cycle-magnetic sections.

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