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Stability of Fe,Al-bearing bridgmanite in the lower mantle and synthesis of pure Fe-bridgmanite.

ABSTRACT: The physical and chemical properties of Earth's mantle, as well as its dynamics and evolution, heavily depend on the phase composition of the region. On the basis of experiments in laser-heated diamond anvil cells, we demonstrate that Fe,Al-bearing bridgmanite (magnesium silicate perovskite) is stable to pressures over 120 GPa and temperatures above 3000 K. Ferric iron stabilizes Fe-rich bridgmanite such that we were able to synthesize pure iron bridgmanite at pressures between ~45 and 110 GPa. The compressibility of ferric iron-bearing bridgmanite is significantly different from any known bridgmanite, which has direct implications for the interpretation of seismic tomography data.

SUBMITTER: Ismailova L

PROVIDER: S-EPMC4956391 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Stability of Fe,Al-bearing bridgmanite in the lower mantle and synthesis of pure Fe-bridgmanite.

Ismailova Leyla L Bykova Elena E Bykov Maxim M Cerantola Valerio V McCammon Catherine C Boffa Ballaran Tiziana T Bobrov Andrei A Sinmyo Ryosuke R Dubrovinskaia Natalia N Glazyrin Konstantin K Liermann Hanns-Peter HP Kupenko Ilya I Hanfland Michael M Prescher Clemens C Prakapenka Vitali V Svitlyk Volodymyr V Dubrovinsky Leonid L

Science advances 20160715 7

The physical and chemical properties of Earth's mantle, as well as its dynamics and evolution, heavily depend on the phase composition of the region. On the basis of experiments in laser-heated diamond anvil cells, we demonstrate that Fe,Al-bearing bridgmanite (magnesium silicate perovskite) is stable to pressures over 120 GPa and temperatures above 3000 K. Ferric iron stabilizes Fe-rich bridgmanite such that we were able to synthesize pure iron bridgmanite at pressures between ~45 and 110 GPa. ...[more]

PMID: 27453945

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