STEM-EELS Investigation of Planar Defects ...
Document type :
Article dans une revue scientifique
DOI :
Permalink :
Title :
STEM-EELS Investigation of Planar Defects in Olivine in the Allende Meteorite
Author(s) :
Marinova, Maya [Auteur]
Institut Michel Eugène Chevreul - FR 2638 [IMEC]
Leroux, Hugues [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Cuvillier, Priscille [Auteur]
Gloter, Alexandre [Auteur]
Jacob, Damien [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]

Institut Michel Eugène Chevreul - FR 2638 [IMEC]
Leroux, Hugues [Auteur]

Unité Matériaux et Transformations - UMR 8207 [UMET]
Cuvillier, Priscille [Auteur]
Gloter, Alexandre [Auteur]
Jacob, Damien [Auteur]

Unité Matériaux et Transformations - UMR 8207 [UMET]
Journal title :
Minerals
Abbreviated title :
Minerals
Volume number :
11
Pages :
35
Publisher :
MDPI AG
Publication date :
2021
ISSN :
2075-163X
English abstract : [en]
The present study focuses on a detailed structural investigation at atomic scale of the planar defects that appear in the olivine grains in the Allende meteorite, and it aims to clarify their nature and the related formation ...
Show more >The present study focuses on a detailed structural investigation at atomic scale of the planar defects that appear in the olivine grains in the Allende meteorite, and it aims to clarify their nature and the related formation mechanism. The investigation was performed using advanced spectro-microscopy techniques such as atomically resolved high-angle annular dark field (HAADF) images coupled with electron energy loss spectroscopy in the scanning transmission electron microscopy mode (STEM-EELS). Two prominent structural features appear in the investigated olivine grains: (i) Exsolution platelets with a thickness between 2 and 10 nm with the spinel structure and chemical composition expressed as a solid solution between magnetite, chromite, and MgAl2O4. (ii) Thinner planar defects appeared with thickness between 2 to 4 atomic planes, which were rich in Fe and had a strong Fe3+ contribution. The structure of these defects was described by the crystalline lattice of the olivine grains with small distortion of the measured cationic distances, which can be related to Fe3+-Si substitution in the tetrahedral sites. Those metastable defects should have preceded the formation of the thicker spinel exsolutions and could have formed during an oxidizing event in the Allende parent body.Show less >
Show more >The present study focuses on a detailed structural investigation at atomic scale of the planar defects that appear in the olivine grains in the Allende meteorite, and it aims to clarify their nature and the related formation mechanism. The investigation was performed using advanced spectro-microscopy techniques such as atomically resolved high-angle annular dark field (HAADF) images coupled with electron energy loss spectroscopy in the scanning transmission electron microscopy mode (STEM-EELS). Two prominent structural features appear in the investigated olivine grains: (i) Exsolution platelets with a thickness between 2 and 10 nm with the spinel structure and chemical composition expressed as a solid solution between magnetite, chromite, and MgAl2O4. (ii) Thinner planar defects appeared with thickness between 2 to 4 atomic planes, which were rich in Fe and had a strong Fe3+ contribution. The structure of these defects was described by the crystalline lattice of the olivine grains with small distortion of the measured cationic distances, which can be related to Fe3+-Si substitution in the tetrahedral sites. Those metastable defects should have preceded the formation of the thicker spinel exsolutions and could have formed during an oxidizing event in the Allende parent body.Show less >
Language :
Anglais
Peer reviewed article :
Oui
Audience :
Non spécifiée
Administrative institution(s) :
Université de Lille
CNRS
INRA
ENSCL
CNRS
INRA
ENSCL
Collections :
Research team(s) :
Matériaux Terrestres et Planétaires
Submission date :
2021-02-05T09:46:31Z