Results 41 to 50 of about 406 (161)

Thermoelasticity of Fe3+‐ and Al‐bearing bridgmanite: Effects of iron spin crossover

Geophysical Research Letters, 2016
We report ab initio (LDA + Usc) calculations of thermoelastic properties of ferric iron (Fe3+)‐ and aluminum (Al)‐bearing bridgmanite (MgSiO3 perovskite), the main Earth forming phase, at relevant pressure and temperature conditions and compositions ...
Gaurav Shukla, Matteo Cococcioni, Renata M. Wentzcovitch   +2 more
doaj   +1 more source

Recreating Giants Impacts in the Laboratory: Shock Compression of MgSiO3 Bridgmanite to 14 Mbar

Geophysical Research Letters, 2020
Understanding giant impacts requires accurate description of how extreme pressures and temperatures affect the physical properties of the constituent materials.
Marius Millot, Shuai Zhang, Dayne E. Fratanduono, Federica Coppari, Sebastien Hamel, Burkhard Militzer, Dariia Simonova, Svyatoslav Shcheka, Natalia Dubrovinskaia, Leonid Dubrovinsky, Jon H. Eggert   +10 more
doaj   +1 more source

Six ‘Must-Have’ Minerals for Life’s Emergence: Olivine, Pyrrhotite, Bridgmanite, Serpentine, Fougerite and Mackinawite

Life, 2020
Life cannot emerge on a planet or moon without the appropriate electrochemical disequilibria and the minerals that mediate energy-dissipative processes. Here, it is argued that four minerals, olivine ([Mg>Fe]2SiO4), bridgmanite ([Mg,Fe]SiO3), serpentine (
Michael J. Russell, Adrian Ponce
doaj   +1 more source

Modeling of Seismic Anisotropy Observations Reveals Plausible Lowermost Mantle Flow Directions Beneath Siberia

Geochemistry, Geophysics, Geosystems, 2021
Observations of seismic anisotropy just above the core‐mantle boundary are a powerful way to understand the dynamics of the lowermost mantle. Here we present models of seismic anisotropy in the lowermost mantle beneath Siberia based on new and previously
Neala Creasy, Angelo Pisconti, Maureen D. Long, Christine Thomas   +3 more
doaj   +1 more source

A Machine‐Learning Surrogate for Differentiable Phase Equilibrium Modeling of Mantle Rocks on a Planetary Scale

Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 5, October 2026.
Abstract Modeling processes within Earth's and other planetary bodies' mantle requires constraints from phase equilibrium to infer how changes in phase abundance and composition affect physical properties and geochemical processes. When applying such thermodynamic models on a planetary scale, performance becomes especially crucial.
Philip Hartmeier, Pierre Lanari
wiley   +1 more source

Formation of an Al‐Rich Niccolite‐Type Silica in Subducted Oceanic Crust: Implications for Water Transport to the Deep Lower Mantle

Geophysical Research Letters, 2022
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 in multicomponent metabasaltic or metasediment compositions relevant to ...
Lu Liu, Hongsheng Yuan, Yao Yao, Ziqiang Yang, Federico Aiace Gorelli, Nico Giordano, Lixin He, Eiji Ohtani, Li Zhang   +8 more
doaj   +1 more source

IGyTheM: Integrating Geodynamics With Thermodynamics Using Machine Learning

Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 5, October 2026.
Abstract Achieving a comprehensive understanding of mantle convection requires integrated models that couple mantle dynamics with thermodynamic properties. Although advances in computational geodynamics have substantially improved our ability to simulate the underlying physical processes, incorporating thermodynamics into self‐consistent geodynamic ...
Qian Yuan, Paul D. Asimow, Michael Gurnis, Paula Antoshechkina, Junjie Dong   +4 more
wiley   +1 more source

First Observation of Quenched Davemaoite to Ambient Conditions: Its Electron Diffraction Pattern

Geophysical Research Letters
Calcium‐rich silicate perovskite (davemaoite) has been for the first time investigated at ambient pressure by electron diffraction in transmission electron microscopy.
Nobuyoshi Miyajima, Lin Wang, Tomoo Katsura   +2 more
doaj   +1 more source

Dehydration Melting Below the Undersaturated Transition Zone

Geochemistry, Geophysics, Geosystems, 2020
A reflector 70–130 km below the base of the transition zone beneath Tibet is observed in receiver functions and underside seismic reflections, at depths consistent with the transition of garnet to bridgmanite.
W. R. Panero, C. Thomas, R. Myhill, J. S. Pigott, C. Raepsaet, H. Bureau   +5 more
doaj   +1 more source

Gravitational Stability of Hydrated SiO2 and Basaltic Crust in the Lower Mantle

Geophysical Research Letters, Volume 53, Issue 15, 16 August 2026.
Abstract We determined thermal equations of state of hydrated stishovite and CaCl2‐type SiO2 up to 100 GPa and 3,000 K to assess the gravitational stability of hydrated stishovite and basaltic crust in the lower mantle. Using machine‐learning based atomistic simulations, we examined three hydrogen dissolution mechanisms: hydrogarnet‐type, interstitial ...
Yanyao Zhang, Chenxing Luo
wiley   +1 more source