Fall 2019

Tuesdays at 3:30 PM
Natural Science Annex 101

October 1, 2019

Speaker: Scott Jasechko, UC Santa Barbara

Title: Drilling deeper wells only a short term ‘solution’ to water stress


Host: Margaret Zimmer

October 8, 2019

Speaker: Adi Torfstein, Hebrew Univeristy, Jerusalem

Title: Late Quaternary shifts in dust and rain patterns across the Levant and the Sahara Desert: lessons towards a warming world


Host: Adina Paytan

October 15, 2019

Speaker: Donna Blackman, UC San Diego

Title: Oceanic Core Complexes- use of their geophysical structure to assess interplay between tectonics, magmatism, and seawater circulation at slow-spreading centers


Host: Andrew Fisher

October 22, 2019

Speaker: Laura Schaefer, Stanford

Title: Atmosphere-Mantle feedbacks: importance of mantle oxidation state on atmospheric evolution

Abstract: The oxidation state of a rocky planet’s mantle has a strong influence on the composition of secondary atmospheres formed through outgassing. Understanding how mantle oxidation state depends on planetary bulk composition and how it changes with time due to planetary differentiation, atmospheric outgassing, and interactions with a planet’s volatile envelope is crucial to accurately predicting atmospheric compositions of rocky exoplanets. Distinguishing biosignature gases from geosignatures (false positive biosignatures produced by natural geological processes) will depend on understanding the geological processes operating on planets of different size and composition compared to the Earth. In this talk, I discuss models that explore how bulk composition, atmospheric escape and planetary differentiation (metal-silicate separation) influence mantle oxidation state and the resulting outgassed atmosphere. These and future models can help select the best exoplanetary targets for detailed characterization by future telescopes like the James Webb Space Telescope (JWST) by identifying planets with lower chances for producing false positive biosignatures.


Host: Jacob Abrahams

October 29 , 2019

Speaker: Baptiste Journaux, University of Washington


Host: Jason Ott and Myriam Telus

November 5, 2019

Speaker: Julie Meachen, Des Moines University

Title: Rappelling into the Pleistocene: A study of faunal response to a changing world


Host: Adrienne Ricker and Paul Koch

November 12, 2019

Speaker: Carlie Pietsch, San Jose State University


Host: Matthew Clapham

November 19, 2019

Speaker: Bradley Gooch, UC Davis


Host: Adam Price and Jenny Pensky

November 26, 2019

Speaker: Aditi Sheshadri, Stanford


Host: Nicole Feldl

December 3, 2019

Speaker: Ariana Ortiz, UCSC and UC Berkeley

Title: Carbon Sequestration in Wetlands: an interplay between burial and export


Host: Margaret Zimmer