Titre :

Pure climb creep mechanism drives flow in Earth's lower mantle

Auteur(s) :

Boioli, Francesca [Auteur]
LEM, UMR 104 CNRS-ONERA, Université Paris Saclay (COmUE) [Châtillon]
Université de Lille
Unité Matériaux et Transformations - UMR 8207 [UMET]
Carrez, Philippe [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Cordier, Patrick [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Devincre, Benoit [Auteur]
Gouriet, Karine [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Hirel, Pierre [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Kraych, Antoine [Auteur]
LEM, UMR 104 CNRS-ONERA, Université Paris Saclay (COmUE) [Châtillon]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Ritterbex, Sebastian [Auteur]
Ehime University [Matsuyama, Japon]
Unité Matériaux et Transformations - UMR 8207 [UMET]

Titre de la revue :

Science Advances

Numéro :

3

Pagination :

e1601958

Date de publication :

2017-11-17

Discipline(s) HAL :

Planète et Univers [physics]/Sciences de la Terre
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]

Résumé en anglais : [en]

At high pressure prevailing in the lower mantle, lattice friction opposed to dislocation glide becomes very high, as reported in recent experimental and theoretical studies. We examine the consequences of this high resistance ...
Lire la suite >At high pressure prevailing in the lower mantle, lattice friction opposed to dislocation glide becomes very high, as reported in recent experimental and theoretical studies. We examine the consequences of this high resistance to plastic shear exhibited by ringwoodite and bridgmanite on creep mechanisms under mantle conditions. To evaluate the consequences of this effect, we model dislocation creep by dislocation dynamics. The calculation yields to an original dominant creep behavior for lower mantle silicates where strain is produced by dislocation climb, which is very different from what can be activated under high stresses under laboratory conditions. This mechanism, named pure climb creep, is grain-size–insensitive and produces no crystal preferred orientation. In comparison to the previous considered diffusion creep mechanism, it is also a more efficient strain-producing mechanism for grain sizes larger than ca. 0.1 mm. The spe-cificities of pure climb creep well match the seismic anisotropy observed of Earth's lower mantle.Lire moins >

Langue :

Anglais

Audience :

Internationale

Vulgarisation :

Non

Établissement(s) :

Université de Lille
ENSCL
CNRS
INRA

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Équipe(s) de recherche :

Plasticité

Date de dépôt :

2019-05-16T17:19:52Z
2024-04-16T12:40:22Z