Who: Dr. Kathryn Snell
Title: "Paleoclimate and paleoelevation in the western United States, 80 Ma to Present"
Where: Hubbs 4500
When: Monday, October 14th. Refreshments at 3:00PM, Talk at 3:15PM
Paleoclimate and paleoelevation in the western United States, 80 Ma to Present
The western USA evolved through the last 80 Ma in response to the transition from dominantly contractional to dominantly extensional tectonics, and from greenhouse to icehouse climate conditions with progressive aridification. Stable isotopes are used to reconstruct past climate and elevation by exploiting sensitivities of the isotopic composition of water, as recorded in authigenic minerals, to temperature and altitude. However, the carbonate clumped isotope thermometer provides estimates of paleotemperature and the oxygen isotope composition of water, in ways that remove some assumptions. I'll present results from an ongoing study of paleotemperatures for the western USA using clumped isotope paleotemperature estimates as a record of summer temperatures in ancient lakes and soils, combined with compilation of previous paleobotanical records of MAT. With these data, we will address current questions about the climatic and tectonic evolution of the western USA.
BIO: Katie did her PhD with Paul Koch at UC Santa Cruz, and worked on terrestrial paleoclimate during the early Cenozoic and paleoelevation of the Late Cretaceous Nevadaplano. She currently a postdoc at Caltech, where she has been working with John Eiler and Brian Wernicke to expand this work to look broadly at terrestrial paleoclimate and paleoelevation in the western USA since the Cretaceous using compiled paleotemperture records. In addtion to these main topics, she has dabbled in d13C chemostratigraphy in China across the K-Pg boundary, paleoelevation and diagenesis studies in Tibet, diagenesis of aragonitic samples.