Physical Properties of Iron-Bearing Silicate Glasses under Lower Mantle Pressures

Abstract

Silicate melts are suggested to exist at the bottom of the Earth’s mantle and may play important roles in the thermal and chemical evolution of the Earth. Silicate glasses provide valuable analogues for such melts, as many of their physical properties resemble those of the liquid state. This article reviews our recent experimental investigations of the physical properties of iron-bearing silicate glasses under pressure conditions relevant to the lower mantle, including measurements of elastic-wave velocity, electrical conductivity, and Mössbauer spectroscopy. These measurements provide key constraints for understanding the stability and behavior of silicate melts at the base of the mantle.