Titre :

A new tool to probe lithosphere evolution: OH signatures of pyroxenes

Auteur(s) :

Ingrin, Jannick [Auteur]
School of Earth Sciences [Hangzhou]
Unité Matériaux et Transformations - UMR 8207 [UMET]

Titre de la manifestation scientifique :

EGU General Assembly 2021

Organisateur(s) de la manifestation scientifique :

EGU

Ville :

Vienna

Pays :

Autriche

Date de début de la manifestation scientifique :

2021-04-19

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]

Four OH stretching bands in the frequency range 3300 – 3700 cm-1 dominate the infrared spectraof lithospheric pyroxenes. Depending on their metasomatic history or geodynamic origin, theyhave characteristic OH signatures. ...
Lire la suite >Four OH stretching bands in the frequency range 3300 – 3700 cm-1 dominate the infrared spectraof lithospheric pyroxenes. Depending on their metasomatic history or geodynamic origin, theyhave characteristic OH signatures. Pyroxenes from continental lithosphere that undergone “wet”metasomatism have distinct signature of those having undergone “dry” metasomatism. Pyroxenesfrom oceanic lithosphere have yet a third type of signature. Our most recent analyses of xenolithsand a critical review of the literature show that the phenomenon is widely distributed amongcontinents and oceans. The phenomenon affects simultaneously opx and cpx from the same rockand various lithologies: peridotites, pyroxenites and granulites. In continental lithosphere,pyroxenes affected by “wet” metasomatism are dominated by OH bands at 3600 and 3415 cm-1 foropx and 3635 and 3445 cm-1 for cpx . Whereas pyroxenes affected by “dry” metasomatism aredominated by OH bands at 3570 and 3515 cm-1 for opx and 3595 and 3515 cm-1 for cpx. Opxsfrom oceanic lithosphere have OH spectra dominated by the band at 3415 cm-1, and with a smallerby bands at 3520 and 3570 cm-1 (Fig. 1).In all these observations it was not possible to correlate the signatures with a specific major, minoror trace element. Therefore, the exact nature of the observed signatures remains unidentified.Notwithstanding, these OH signatures are representative of specific lithospheric events and offer apotential new benchmark for the study of lithospheric processes.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

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 :

2021-04-30T08:56:08Z
2021-06-10T14:45:15Z
2021-06-10T14:51:09Z
2021-06-10T14:56:00Z