Discovery of the Fe-analogue of akimotoite in the shocked Suizhou L6 chondrite
書誌事項
- 公開日
- 2017-02-15
- 権利情報
-
- https://creativecommons.org/licenses/by/4.0
- https://creativecommons.org/licenses/by/4.0
- DOI
-
- 10.1038/srep42674
- 公開者
- Springer Science and Business Media LLC
説明
<jats:title>Abstract</jats:title><jats:p>We report the first natural occurrence of the Fe-analogue of akimotoite, ilmenite-structured MgSiO<jats:sub>3</jats:sub>, a missing phase among the predicted high-pressure polymorphs of Fe-pyroxene, with the composition (Fe<jats:sup>2+</jats:sup><jats:sub>0.48</jats:sub>Mg<jats:sub>0.37</jats:sub>Ca<jats:sub>0.04</jats:sub>Na<jats:sub>0.04</jats:sub>Mn<jats:sup>2+</jats:sup><jats:sub>0.03</jats:sub>Al<jats:sub>0.03</jats:sub>Cr<jats:sup>3+</jats:sup><jats:sub>0.01</jats:sub>)<jats:sub>Σ=1.00</jats:sub>Si<jats:sub>1.00</jats:sub>O<jats:sub>3</jats:sub>. The new mineral was approved by the International Mineralogical Association (IMA 2016-085) and named hemleyite in honour of Russell J. Hemley. It was discovered in an unmelted portion of the heavily shocked L6 Suizhou chondrite closely associated to olivine, clinoenstatite and Fe-bearing pyroxene with a composition nearly identical to that of hemleyite. We also report the first single-crystal X-ray diffraction study of a Si-bearing, ilmenite-structured phase. The fact that hemleyite formed in a meteorite exposed to high pressures (<20 GPa) and temperatures (<2000 °C) during impact-induced shocks indicates that it could play a crucial role at the bottom of the Earth’s mantle transition zone and within the uppermost lower mantle.</jats:p>
収録刊行物
-
- Scientific Reports
-
Scientific Reports 7 (1), 42674-, 2017-02-15
Springer Science and Business Media LLC
