A plot of genus extinction intensity throughout the past 540Ma (from Wikipedia)

The end-Permian mass extinction (ca. 251.9Ma) represents the most devastating loss of biodiversity during the Phanerozoic. The main phase in the latest Permian decimating ~60% of all marine species, including all plankton and some benthic groups (e.g. Erwin et al., 1994), however, spanned relatively short time (<61,000 years, Burgess et al., 2014). A negative carbon isotope (δ13C) excursion that accompanies the event suggests a significant perturbation to the global carbon cycle, likely induced by CO2 emissions during eruption of the Siberian Traps large igneous province (Clapham and Payne, 2011). Because the carbon cycle is linked with the Ca and Sr cycles through chemical weathering and carbonate precipitation, Ca and Sr isotopes could reveal key information about biochemical changes that occurred during the extinction.
This project utilizes high-precision analyses of Ca (δ44/40Ca), radiogenic Sr (87Sr/86Sr), and stable Sr (δ88/86Sr) isotope abundances in marine carbonate rocks and box-modeling to understand changes of weathering, hydrothermal, carbonate precipitation fluxes, and associated chemical changes across the P-Tr extinction. (Check our AGU2017 presentation!)