Albertiana Research Article
Dal Corso, J. 2025. Carnian Events. Albertiana, vol. 49, 1–11.
Abstract – The Carnian Pluvial Episode (CPE; Late Triassic) was an interval of C-cycle perturbations, global warming and biological turnover, occurring between ca. 234 and 232 Ma. The C-cycle perturbations are recorded as discrete sharp negative C-isotope excursions (NCIEs) in marine and terrestrial sedimentary successions around the world, and at least two warming phases are shown by O-isotope data from conodont apatite. The estimated duration of each CPE’s NCIE is similar to the duration of NCIEs associated with other Mesozoic major environmental and biological changes. Also similar with other events are the calculated rates of CO2 emissions into the atmosphere–ocean system during each NCIE. The successive C-cycle perturbations could have had different impacts on environments and ecosystems. Hence, considering the CPE as a single “event” results in flawed understanding of the triggers and mechanisms of Carnian paleoenvironmental changes, and bias comparative studies. I here argue that a change in perspective is necessary, including considering the Carnian C-cycle perturbations as separate events, and revising the current most common subdivision of the Carnian stage into new substages that allow for better stratigraphic control. This is relevant because the events that occurred during the Carnian might have caused the rise of flora and fauna that later dominated terrestrial and marine ecosystems, e.g., dinosaurs and pelagic calcifiers. The fact that these events occurred within a maximum timeframe of 2.5 million years remains significant, and their temporal closeness should be acknowledged.