Results 21 to 30 of about 406 (161)

Low-spin ferric iron in primordial bridgmanite crystallized from a deep magma ocean

Scientific Reports, 2021
The crystallization of the magma ocean resulted in the present layered structure of the Earth’s mantle. An open question is the electronic spin state of iron in bridgmanite (the most abundant mineral on Earth) crystallized from a deep magma ocean, which ...
Yoshiyuki Okuda, Kenji Ohta, Yu Nishihara, Naohisa Hirao, Tatsuya Wakamatsu, Sho Suehiro, Saori I. Kawaguchi, Yasuo Ohishi   +7 more
doaj   +1 more source

Does Heterogeneous Strain Act as a Control on Seismic Anisotropy in Earth’s Lower Mantle?

Frontiers in Earth Science, 2020
Plastic deformation and texture development in minerals of the lower mantle can result in seismic anisotropy, and studying deformation of lower mantle materials is therefore important for interpreting lower mantle flow.
Samantha Couper, Sergio Speziale, Hauke Marquardt, Hanns-Peter Liermann, Lowell Miyagi   +4 more
doaj   +1 more source

Back-transformation processes in high-pressure minerals: implications for planetary collisions and diamond transportation from the deep Earth

Progress in Earth and Planetary Science, 2022
We conducted back-transformation experiments in ringwoodite, bridgmanite, and lingunite at 0.47–8.1 GPa and 310–920 °C by in situ X-ray observation method. Ringwoodite back-transformed to olivine by grain-boundary nucleation and growth mechanism.
Tomoaki Kubo, Ko Kamura, Masahiro Imamura, Yoshinori Tange, Yuji Higo, Masaaki Miyahara   +5 more
doaj   +1 more source

Incorporation mechanism of Fe and Al into bridgmanite in a subducting mid-ocean ridge basalt and its crystal chemistry

Scientific Reports, 2021
The compositional difference between subducting slabs and their surrounding lower-mantle can yield the difference in incorporation mechanism of Fe and Al into bridgmanite between both regions, which should cause heterogeneity in physical properties and ...
Akihiko Nakatsuka, Hiroshi Fukui, Seiji Kamada, Naohisa Hirao, Makio Ohkawa, Kazumasa Sugiyama, Takashi Yoshino   +6 more
doaj   +1 more source

Dynamical and elastic properties of MgSiO₃ perovskite (bridgmanite) [PDF]

Geophysical Research Letters, 2016
AbstractWe report on the lattice dynamics of MgSiO3 perovskite (bridgmanite). Phonon spectroscopy was performed employing inelastic X‐ray scattering from single crystals, and the results were confronted to ab initio calculations. We observe a remarkable agreement between experiment and theory, and provide accurate results for phonon dispersion ...
Wehinger, Björn, Bosak, Alexeï, Nazzareni, Sabrina, Antonangeli, Daniele, Mirone, Alessandro, Chaplot, Samrath Lal, Mittal, Ranjan, Ohtani, Eiji, Shatskiy, Anton, Saxena, Surendra, Ghose, Subrata, Krisch, Michael   +11 more
openaire   +5 more sources

Aluminous hydrous magnesium silicate as a lower-mantle hydrogen reservoir: a role as an agent for material transport

Scientific Reports, 2022
The potential for storage of a large quantity of water/hydrogen in the lower mantle has important implications for the dynamics and evolution of the Earth.
Akihiko Nakatsuka, Akira Yoshiasa, Makio Ohkawa, Eiji Ito   +3 more
doaj   +1 more source

Ferropericlase Control of Lower Mantle Rheology: Impact of Phase Morphology

Geochemistry, Geophysics, Geosystems, 2020
The rheological properties of Earth's lower mantle play a key role for global mantle dynamics. The mineralogy of the lower mantle can be approximated as a bridgmanite‐ferropericlase mixture.
M. Thielmann, G. J. Golabek, H. Marquardt   +2 more
doaj   +1 more source

Bridgmanite's ferric iron content determined Earth's oxidation state. [PDF]

Nat Geosci
Abstract Bridgmanite, a magnesium-rich silicate perovskite, is the most prevalent mineral in Earth’s lower mantle and contains substantial quantities of ferric (oxidized) iron, even in equilibrium with iron metal. Mixing of oxygen-rich material from the lower mantle could have raised the oxidation state of the upper mantle to its present ...
Wang F, Wang L, Fei H, Miyajima N, McCammon C, Frost DJ, Katsura T.   +6 more
europepmc   +3 more sources

On the global geodynamic consequences of different phase boundary morphologies [PDF]

Solid Earth
Phase transitions can influence mantle convection patterns, inhibiting or promoting vertical flow. One such transition is the ringwoodite-to-bridgmanite plus periclase transition, which has a negative Clapeyron slope and therefore reduces mantle flow ...
G. T. Morgan, J. H. Davies, R. Myhill, J. Panton   +3 more
doaj   +1 more source

Disproportionation of Iron in Almandine‐Pyrope‐Grossular Garnet From 25 to 65 GPa

Geochemistry, Geophysics, Geosystems, 2023
The production of metal via the iron disproportionation reaction in the deep Earth has been a long debated topic with important implications for the geochemistry of the lower mantle.
K. E. Swadba, A. H. Davis, C. C. Zurkowski, S. Chariton, V. B. Prakapenka, A. J. Campbell   +5 more
doaj   +1 more source