Wildfires, Weathering and Warming: A High Latitude Southern Hemisphere paleoclimate record of the Triassic from Tasmania

Tasmania was located at 62-74° S in the Triassic, a position today occupied by the frozen rocky Antarctic continent. Sedimentary archives of the Triassic from Tasmania present a unique opportunity to examine a high latitude archive of a world that was in a significant state of climatic and environmental flux from the end-Permian mass extinction (~252 Ma) to the Late Triassic, Norian Manicouagen bollide impact, ~214 Ma . Here we present new sedimentological and geochemical data spanning these major events from two core records (~300m each) located in Bicheno, Eastern Tasmania. These cores represent deposition of organic rich sediments in a coastal environment, that spans the Permo–Triassic boundary through the Norian. This data includes new carbon isotopes, charcoalfied wood abundances, sedimentological evaluation and pXRF data. The Permo-Triassic Event (PTE) is marked by a -6‰ excursion in δ¹³C_TOC  with a change from Upper Parmeener Marine sequence limestones to more organic rich Upper Parmeener Freshwater sequences which includes mudstones, volcanic sandstones and tuffs. The Earliest Triassic is relatively condensed suggesting a relatively cold interval, with low sedimentation following on from the PTE. Other notable events include the Carnian Pluvial Event (CPE), with a marked increase in the abundance of charcoalified fossil wood, a -4‰ δ¹³C_TOC excursion and increased weathering suggesting significant changes to the hydrological cycle and the climate during this interval. There is also evidence of the Middle Norian Event with a -4‰ δ¹³C_TOC  excursion. This sedimentological and chemostratigraphic record from Tasmania represents a unique high latitude Southern Hemisphere record of climate change through the Triassic with evidence of significant paleoclimatic and environmental change near the South Pole.