Related Experiment Video
Updated: Jun 25, 2025

Stable Aqueous Suspensions of Manganese Ferrite Clusters with Tunable Nanoscale Dimension and Composition
Published on: February 5, 2022
Pressure stabilizes ferrous iron in bridgmanite under hydrous deep lower mantle conditions
Li Zhang1, Yongjin Chen2, Ziqiang Yang2
1Center for High Pressure Science and Technology Advanced Research, Shanghai, China. zhangli@hpstar.ac.cn.
Abstract:
Earth's lower mantle is a potential water reservoir. The physical and chemical properties of the region are in part controlled by the Fe3+/ΣFe ratio and total iron content in bridgmanite. However, the water effect on the chemistry of bridgmanite remains unclear. We carry out laser-heated diamond anvil cell experiments under hydrous conditions and observe dominant Fe2+ in bridgmanite (Mg, Fe)SiO3 above 105 GPa under the normal geotherm conditions corresponding to depth > 2300 km, whereas Fe3+-rich bridgmanite is obtained at lower pressures. We further observe FeO in coexistence with hydrous NiAs-type SiO2 under similar conditions, indicating that the stability of ferrous iron is a combined result of H2O effect and high pressure. The stability of ferrous iron in bridgmanite under hydrous conditions would provide an explanation for the nature of the low-shear-velocity anomalies in the deep lower mantle. In addition, entrainment from a hydrous dense layer may influence mantle plume dynamics and contribute to variations in the redox conditions of the mantle.
More Related Videos
11:50Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions
Published on: June 13, 2015
06:04Simulation of the Planetary Interior Differentiation Processes in the Laboratory
Published on: November 15, 2013
Related Concept Videos
Ferromagnetism
Temperature Dependent Deformation
Hydration of Cement
Complexation Equilibria: Factors Influencing Stability of Complexes