Abstract

Processes in Earth’s mantle govern our planet’s inner dynamics and control surface plate tectonics. As such, a quantitative understanding of the physical properties of the mantle is pivotal to model Earth’s dynamic evolution, including the long-term chemical interactions between mantle and atmosphere that are vital to the development of habitability on Earth. Here, I will discuss recent results of experimental measurements to constrain physical properties of Earth mantle minerals at conditions relevant to Earth’s deep mantle. The experiments are performed by optical spectroscopy and synchrotron x-ray diffraction in (heated) diamond-anvil cells. I will focus on (i) the seismic signature of “water” in Earth’s transition zone constrained by multi-sample loading Brillouin spectroscopy experiments, and (ii) the effect of the iron spin transition in Earth’s lower mantle on the compression behaviour of ferropericlase measured by time-resolved x-ray diffraction in dynamic diamond-anvil cells.

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