Natural (Mg,Fe)SiO3-ilmenite and -perovskite in the Tenham meteorite.
Science
; 277(5329): 1084-6, 1997 Aug 22.
Article
em En
| MEDLINE
| ID: mdl-9262473
The minerals (Mg,Fe)SiO3-ilmenite and -perovskite were identified in the shock-induced veins in the Tenham chondritic meteorite. Both phases are inferred to have transformed from pyroxene at high pressures and temperatures by shock metamorphism. Columnar-shaped ilmenite grains, one of two types of morphologies, have a topotaxial relationship with neighboring pyroxene grains, indicating shear transformation. Granular-shaped perovskite grains showed a diffraction pattern consistent with orthorhombic perovskite, but these grains were not stable under the electron beam irradiation and became amorphous. The higher iron concentration in both phases compared with those experimentally reported may suggest their metastable transition from enstatite because of shock compression.
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Óxidos
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Titânio
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Silicatos
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Compostos de Magnésio
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Compostos de Ferro
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Compostos de Cálcio
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Meteoroides
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Ferro
Idioma:
En
Revista:
Science
Ano de publicação:
1997
Tipo de documento:
Article