Geocheminar Winter-2018

Geophysical and geochemical observations indicate anomalous mantle composition and structure in the deep mantle, for example in the Large Low Shear Velocity Provinces. Previous hypotheses of the compositional differences mainly include: major minerals mode variation, Fe/Mg enhancement of major minerals, H in major minerals and silicate melt. In this talk, I will discuss three aspects of a petrological model of accessory phases in a bulk silicate rock: (1) their role in creating both geophysical and geochemical anomalies; (2) constraints on the composition and abundance of the accessory phases; (3) dynamic process leading to the origin, enrichment and preservation of the accessory phases in the mantle from the early Earth to the present day.