Tempo of the end-Permian event: High-resolution cyclostratigraphy at the Permian-Triassic boundary

The Permian-Triassic (P-T) boundary is marked by the most severe mass extin ction in the geologic record. High-resolution cyclo-stratigraphy on a 10(4) yr scale across the P-T boundary in a core from the Carnic Alps (Austria) revealed significant cycles in the ratio similar to 40:10:4.7:2.3 m, identi fied with Milankovitch cycles of similar to 412:100:40:20 k.y. (eccentricit y 1 and 2, obliquity, and precession), Wavelet analysis indicates continuit y of deposition across the boundary, with an average accumulation rate of s imilar to 10 cm/k.y. The dramatic faunal changes at the P-T boundary can be constrained within an interval of <60 k.y. (possibly <8 k.y.), with the ac companying sharp negative global carbon-isotope shift within <30 k.y., sugg esting a catastrophic cause.