Title :

Kinetics and detectability of the bridgmanite to post-perovskite transformation in the Earth's D″ layer

Author(s) :

Langrand, Christopher [Auteur]
Andrault, Denis [Auteur]
Durand, Stéphanie [Auteur]
Konôpková, Zuzana [Auteur]
Hilairet, Nadege [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Thomas, Christine [Auteur]
Merkel, Sébastien [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]

Journal title :

Nature communications

Abbreviated title :

Nat Commun

Volume number :

10

Publisher :

Springer Science and Business Media LLC

Publication date :

2019-12

ISSN :

2041-1723

HAL domain(s) :

Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
Chimie/Matériaux
Physique [physics]/Physique [physics]/Géophysique [physics.geo-ph]
Physique [physics]/Astrophysique [astro-ph]
Planète et Univers [physics]/Astrophysique [astro-ph]
Planète et Univers [physics]/Sciences de la Terre

English abstract : [en]

Bridgmanite, the dominant mineral in the Earth’s lower mantle, crystallizes in the perovskite structure and transforms into post-perovskite at conditions relevant for the D′′ layer. This transformation affects the dynamics ...
Show more >Bridgmanite, the dominant mineral in the Earth’s lower mantle, crystallizes in the perovskite structure and transforms into post-perovskite at conditions relevant for the D′′ layer. This transformation affects the dynamics of the Earth’s lowermost mantle and can explain a range of seismic observations. The thickness over which the two phases coexist, however, can extend over 100 km, casting doubt on the assignment of the observed seismic boundaries. Here, experiments show that the bridgmanite to post-perovskite transition in (Mg0.86,Fe0.14)SiO3 is fast on geological timescales. The transformation kinetics, however, affects reflection coefficients of P and S waves by more than one order of magnitude. Thick layers of coexisting bridgmanite and post-perovskite can hence be detected using seismic reflections. Morever, the detection and wave period dependence of D′′ reflections can be used to constrain significant features of the Earth’s lowermost mantle, such as the thickness of the coexistence layer, and obtain information on temperature and grain sizes.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Non spécifiée

European Project :

E.C.7th Framework Program (CALIPSO Transnational Access support)

ANR Project :

Transformations de phase, microstructures, et leur signatures sismiques dans le manteau terrestre

Administrative institution(s) :

Université de Lille
CNRS
INRA
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Matériaux Terrestres et Planétaires

Submission date :

2019-12-16T22:39:03Z
2019-12-17T08:55:10Z