Event Date
Speaker: Dr. Weiyi Liu, Scripps Institution of Oceanography, UC San Diego
Title: From Thermodynamics to Seismology: Constraining Earth’s Deep Interior
Abstract: Understanding the composition and thermal structure of Earth’s deep interior is essential for explaining its dynamics and evolution. Geochemistry alone, however, cannot fully constrain these properties. Seismic observations provide complementary constraints, but interpreting them in terms of composition and temperature requires thermodynamic models that connect material properties to seismic observables. In this talk, I will present a new thermodynamic model for multicomponent liquid iron alloys and its application to constraining the composition and thermal state of Earth’s outer core. I will discuss how inferences depend on the choice of seismic reference model, motivating direct comparisons with seismic data. I will then show how seismic observations (e.g., coda waves and normal modes), combined with thermodynamic models of mantle minerals and liquid iron, can be used to constrain the composition of Earth's mantle and core. These results address whether Earth’s mantle composition is consistent with chondritic proportions, whether seismic observations support compositional differences between the upper and lower mantle, what such differences may reveal about mantle evolution and whether hydrogen is supported as a component of Earth’s core.