Is There a Global Carbonate Layer in the Oceanic Mantle?

Document type :

Article dans une revue scientifique: Article original

Permalink :

http://hdl.handle.net/20.500.12210/37080

Title :

Is There a Global Carbonate Layer in the Oceanic Mantle?

Author(s) :

Hammouda, Tahar [Auteur]
Manthilake, Geeth [Auteur]
Goncalves, Philippe [Auteur]
Chantel, Julien [Auteur]

Unité Matériaux et Transformations - UMR 8207 [UMET]
Guignard, Jérémy [Auteur]
Crichton, Wilson [Auteur]
Gaillard, Fabrice [Auteur]

Journal title :

Geophysical Research Letters

Volume number :

48

Publication date :

2020-12-19

English abstract : [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 ...
Show more >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.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Non spécifiée

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 :

2021-01-21T10:42:00Z

Version history