Titre :

Is There a Global Carbonate Layer in the Oceanic Mantle?

Auteur(s) :

Hammouda, Tahar [Auteur]
Manthilake, Geeth [Auteur]
Goncalves, Philippe [Auteur]
Chantel, Julien [Auteur]
Laboratoire Magmas et Volcans [LMV]
Case Western Reserve University [Cleveland]
Guignard, Jérémy [Auteur]
Crichton, Wilson [Auteur]
Gaillard, Fabrice [Auteur]

Titre de la revue :

Geophysical Research Letters

Numéro :

48

Éditeur :

American Geophysical Union

Date de publication :

2020-12-19

Mot(s)-clé(s) en anglais :

carbon cycle
lithosphere
subduction

Discipline(s) HAL :

Chimie/Matériaux
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
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

Résumé en anglais : [en]

Previous modeling of carbonate subduction by high‐pressure experimentation has allowed to propose scenarios for bulk carbon return to the mantle, but the detailed transfer mechanisms have seldom been studied. We monitored ...
Lire la suite >Previous modeling of carbonate subduction by high‐pressure experimentation has allowed to propose scenarios for bulk carbon return to the mantle, but the detailed transfer mechanisms have seldom been studied. We monitored carbonate–silicate reactions by combining high‐pressure experiments and synchrotron‐based X‐ray diffraction. Carbonates break down at moderate pressure and high temperature and CO2 is trapped at grain boundaries. Further isothermal compression yields melting, which may control continuous carbon introduction, first in the mantle wedge, and next, away from the wedge. Carbon presence has been discussed in a variety of magmatic contexts, under the oceanic lithosphere (hotspots, petit spots, and fossil ridges). We suggest the presence of a global carbon‐rich layer under the oceanic lithosphere that is steadily fed by subduction processes. This layer can be the source of mechanical weakening of the lithosphere–asthenosphere boundary under the oceans. Therefore, carbon‐induced compression melting may be a key mechanism of modern‐style plate tectonics.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Projet Européen :

Electrical Petrology: tracking mantle melting and volatiles cycling using electrical conductivity

Projet ANR :

Clermont-Ferrand centre for research on volcanism
CAP 20-25

Établissement(s) :

Université de Lille
CNRS
INRA
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Équipe(s) de recherche :

Matériaux Terrestres et Planétaires

Date de dépôt :

2021-01-21T10:42:00Z
2021-01-25T11:16:28Z