Earth Seminar 01 May - Assistant Professor Victoria Petryshyn

Taking the Temperature of the Tethys: What stromatolites can tell us about the end-Triassic mass extinctions

Abstract

The end-Triassic mass extinction interval is associated with a sharp rise in atmospheric CO2 and coincided with the eruption of the Central Atlantic Magmatic Province, a large igneous province responsible for the massive atmospheric input of potentially climate-altering volatile compounds. The extinction mechanism is debated, but both short-term cooling related to sulfur aerosols, and longer-term warming related to CO2 emissions—essentially opposite hypotheses—are suggested triggers. Until now, no temperature records spanning this crucial interval were available to provide a baseline or to differentiate between hypothesized mechanisms. Clumped-isotope paleothermometry of shallow marine microbialites are coupled with climate modeling and rare-earth element analyses to reconstruct temperature and environmental conditions of the shallow Tethys and at the extinction horizon.

Biography

Dr. Victoria Petryshyn is an Asst. Professor in the Environmental Studies Program at the University of Southern California. A geobiologist by training, she studies the interactions between Earth and life, specializing in reconstructing climate and environmental conditions during key milestones in the evolution of life, and important transitions in Earth History. She specifically looks at the changes in carbon dioxide/oxygen levels and temperature at times of rapid transformation (such as mass extinctions, glaciations, or radiations).