Abstract
Phase relations in Mg0.5Fe0.5SiO3 and Mg0.25Fe0.75SiO3 were investigated in a pressure range from 72 to 123 GPa on the basis of synchrotron X-ray diffraction measurements in situ at high-pressure and -temperature in a laser-heated diamond-anvil cell (LHDAC). Results demonstrate that Mg0.5Fe0.5SiO3 perovskite is formed as a single phase at 85-108 GPa and 1800-2330 K, indicating a high solubility of FeO in (Mg,Fe)SiO3 perovskite at high pressures. Post-perovskite appears coexisting with perovskite in Mg0.5Fe0.5SiO3 above 106 GPa at 1410 K, the condition very close to the post-perovskite phase transition boundary in pure MgSiO3. The coexistence of perovskite and post-perovskite was observed to 123 GPa. In addition, post-perovskite was formed coexisting with perovskite also in Mg0.25Fe0.75SiO3 bulk composition at 106-123 GPa. In contrast to earlier experimental and theoretical studies, these results show that incorporation of FeO stabilizes perovskite at higher pressures. This could be due to a larger ionic radius of Fe2+ ion, which is incompatible with a small Mg2+ site in the post-perovskite phase.
| Original language | English |
|---|---|
| Pages (from-to) | 319-325 |
| Number of pages | 7 |
| Journal | Physics of the Earth and Planetary Interiors |
| Volume | 160 |
| Issue number | 3-5 |
| DOIs | |
| Publication status | Published - Mar 16 2007 |
| Externally published | Yes |
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Keywords
- D″ layer
- In situ X-ray observation
- Iron
- Perovskite
- Phase transition
- Post-perovskite
ASJC Scopus subject areas
- Geophysics
- Space and Planetary Science
- Physics and Astronomy (miscellaneous)
- Astronomy and Astrophysics
Cite this
Solubility of FeO in (Mg,Fe)SiO3 perovskite and the post-perovskite phase transition. / Tateno, Shigehiko; Hirose, Kei; Sata, Nagayoshi; Ohishi, Yasuo.
In: Physics of the Earth and Planetary Interiors, Vol. 160, No. 3-5, 16.03.2007, p. 319-325.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Solubility of FeO in (Mg,Fe)SiO3 perovskite and the post-perovskite phase transition
AU - Tateno, Shigehiko
AU - Hirose, Kei
AU - Sata, Nagayoshi
AU - Ohishi, Yasuo
PY - 2007/3/16
Y1 - 2007/3/16
N2 - Phase relations in Mg0.5Fe0.5SiO3 and Mg0.25Fe0.75SiO3 were investigated in a pressure range from 72 to 123 GPa on the basis of synchrotron X-ray diffraction measurements in situ at high-pressure and -temperature in a laser-heated diamond-anvil cell (LHDAC). Results demonstrate that Mg0.5Fe0.5SiO3 perovskite is formed as a single phase at 85-108 GPa and 1800-2330 K, indicating a high solubility of FeO in (Mg,Fe)SiO3 perovskite at high pressures. Post-perovskite appears coexisting with perovskite in Mg0.5Fe0.5SiO3 above 106 GPa at 1410 K, the condition very close to the post-perovskite phase transition boundary in pure MgSiO3. The coexistence of perovskite and post-perovskite was observed to 123 GPa. In addition, post-perovskite was formed coexisting with perovskite also in Mg0.25Fe0.75SiO3 bulk composition at 106-123 GPa. In contrast to earlier experimental and theoretical studies, these results show that incorporation of FeO stabilizes perovskite at higher pressures. This could be due to a larger ionic radius of Fe2+ ion, which is incompatible with a small Mg2+ site in the post-perovskite phase.
AB - Phase relations in Mg0.5Fe0.5SiO3 and Mg0.25Fe0.75SiO3 were investigated in a pressure range from 72 to 123 GPa on the basis of synchrotron X-ray diffraction measurements in situ at high-pressure and -temperature in a laser-heated diamond-anvil cell (LHDAC). Results demonstrate that Mg0.5Fe0.5SiO3 perovskite is formed as a single phase at 85-108 GPa and 1800-2330 K, indicating a high solubility of FeO in (Mg,Fe)SiO3 perovskite at high pressures. Post-perovskite appears coexisting with perovskite in Mg0.5Fe0.5SiO3 above 106 GPa at 1410 K, the condition very close to the post-perovskite phase transition boundary in pure MgSiO3. The coexistence of perovskite and post-perovskite was observed to 123 GPa. In addition, post-perovskite was formed coexisting with perovskite also in Mg0.25Fe0.75SiO3 bulk composition at 106-123 GPa. In contrast to earlier experimental and theoretical studies, these results show that incorporation of FeO stabilizes perovskite at higher pressures. This could be due to a larger ionic radius of Fe2+ ion, which is incompatible with a small Mg2+ site in the post-perovskite phase.
KW - D″ layer
KW - In situ X-ray observation
KW - Iron
KW - Perovskite
KW - Phase transition
KW - Post-perovskite
UR - http://www.scopus.com/inward/record.url?scp=33846615882&partnerID=8YFLogxK
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U2 - 10.1016/j.pepi.2006.11.010
DO - 10.1016/j.pepi.2006.11.010
M3 - Article
VL - 160
SP - 319
EP - 325
JO - Physics of the Earth and Planetary Interiors
JF - Physics of the Earth and Planetary Interiors
SN - 0031-9201
IS - 3-5
ER -