Isotopic chemostratigraphy across the Early–Middle Frasnian transition (Late Devonian) on the South Polish carbonate shelf: A reference for the global punctata Event

The coupled high-resolution carbon isotope data from whole-rock limestone and organic matter samples of the transitans (Early Frasnian), punctata and the earliest hassi Zones (Middle Frasnian) from the South Polish carbonate shelf successions reveal the presence of a large, multi-part δ13C excursion, one of the largest known carbon cycle disturbance of Devonian period. This Early–Middle Frasnian (E–MF) δ13C perturbation consists of two positive...