EPSS Colloquium fall-2019

The chemical composition of seawater is a critical boundary condition for reconstructing biogeochemical cycles, interpreting geochemical proxy measurements, and understanding the co-evolution of life and Earth’s surface environments. However, much about the evolution of seawater chemistry remains unknown, and very few quantitative constraints exist on Precambrian ocean composition. I will present a new method using the geochemical behavior of marine evaporite deposits to constrain seawater chemistry, in particular the relative concentrations of sulfate, calcium, and carbonate alkalinity. Using observations of evaporite deposits from the Neogene through the Archean, I will explore the implications of this work for understanding the Great Oxidation Event and Earth’s habitability.