Ethan L. Grossman is a stable isotope geochemist who serves as the Michel T. Halbouty Chair in Geology in the Department of Geology and Geophysics and the Co-Director of the Stable Isotope Geosciences Facility (SIGF) at Texas A&M University (TAMU). During his tenure at TAMU Dr. Grossman and his students have developed and applied stable isotope and trace-element proxies to understand Earth system processes and history, with emphases on paleoclimate, paleoceanography, water resources, and subsurface microbiology. He is author of 89 publications including six book chapters, and a Fellow of the Geological Society of America and the American Association for the Advancement of Science.
Locked within the oxygen isotope ratios (18O/16O) of fossils and microfossils is a record of seawater temperature and δ18O composition. When combined with independent proxies, δ18O values can provide temperature, circulation, climate, and ice volume histories. This approach has led to robust understanding of Earth’s climate for the last 110 million years thanks to the record from deep sea cores; however, climate and especially ocean temperatures for the first 80% of the Phanerozoic (539 - 110 Ma), an interval for which deep sea sediments are not available, are far less constrained. Consequently, we have limited quantitation of the temperatures spanning the evolution and biodiversification of metazoan life, four of the five major mass extinctions, and massive perturbations in the carbon and sulfur cycles.
This talk examines the record for climate change and paleotemperature provided by 50,000+ oxygen isotope analyses of carbonate and phosphate fossils and microfossils. In interpreting this record, I will consider sample integrity and paleoecology, local oceanography, ice volume, and clumped isotope data to reconstruct tropical-subtropical temperatures through the Phanerozoic.
Arranged date for the seminar talk: Jan 24, 2020 at 11:15
BCCR lecture room 4020, Jahnebakken 5