A5064055775- High-pressure geophysics and materials
- Geological and Geochemical Analysis
- earthquake and tectonic studies
Center for High Pressure Science and Technology Advanced Research
2022-2024
RIKEN Center for Biosystems Dynamics Research
2024
SPring-8
2024
University of Science and Technology of China
2022
Abstract Earth’s lower mantle is a potential water reservoir. The physical and chemical properties of the region are in part controlled by Fe 3+ /ΣFe ratio total iron content bridgmanite. However, effect on chemistry bridgmanite remains unclear. We carry out laser-heated diamond anvil cell experiments under hydrous conditions observe dominant 2+ (Mg, Fe)SiO 3 above 105 GPa normal geotherm corresponding to depth > 2300 km, whereas -rich obtained at pressures. further FeO coexistence with...
Abstract Subducted oceanic crust is enriched in free silica. Although being one of the silica polymorphs at lower‐mantle pressures, niccolite‐type phase (Nt‐phase) has not been documented multicomponent metabasaltic or metasediment compositions relevant to subducting crust. Here, we report formation an Al‐rich Nt‐phase (∼24.4 32.4 wt% Al 2 O 3 ), coexisting with Al‐depleted bridgmanite (∼6.4 7.6 δ‐phase, and iron‐rich model hydrated basalts over pressure‐temperature range 84–113 GPa...
Abstract Incorporation of water into mantle compositions can have significant effects on the phase relations in systems. In this study, we synthesized an iron‐rich hexagonal hydrous (referred to as “HH1‐phase”) under high pressure‐temperature ( P ‐ T ) conditions deep lower and determined crystal structure HH1‐phase at 79 GPa using multigrain crystallography method. The chemical formula obtained was Fe 12.76 O 18 H x ∼ 4.5) Fe‐O‐H system. To demonstrate role for storage multicomponent...
Abstract We investigated the compressional and shear velocities, V P S , of HH1‐phase by combining inelastic x‐ray scattering diffraction experiments. In pressure range 64.7–79.6 GPa at room temperature, were measured to be 9.66–11.05 4.9–6.4 km·s⁻ 1 respectively. employed a simplified model quantitatively discuss sound velocity differences between hydrous anhydrous phase assemblages in mid‐lower mantle, revealing that assemblage exhibits increased reduced / ratio compared its counterpart....