MODELING CONTINENTAL WEATHERING ACROSS THE END-PERMIAN MASS EXTINCTION

The end-Permian mass extinction event (EPME) occurred about 252 million years ago and is associated with the loss of 80-90% marine species and 70% terrestrial species. The Siberian Traps volcanism (ST) is postulated to be the driver of the EPME via the release of large amount of CO₂ into the atmosphere. Despite decades of research on the EPME, the impact of the Siberian Traps volcanism and subsequent climatic recovery remain poorly understood. It has been suggested that the Early Triassic warmth is maintained by high CO₂ degassing, and the silicate weathering that can typically sequester CO₂ from the atmosphere may have failed to do so. In order to test this hypothesis, we performed lithium isotope analysis in shales from the Finnmark and Trøndelag Platforms in Norway across the Permian-Triassic transition. The results follow similar trend as those in the carbonate-rich Meishan GSSP section published previously. A dynamic lithium cycle box model is used to explore in the parameter space the effect of increase in silicate weathering rate and intensity. Future work will focus on isotope inversion in cGENIE to better understand the relationship between silicate weathering and subsequent recovery of life in the Early Triassic.