Title :

OH signature of pyroxenes: A new probe for studying lithospheric processes?

Author(s) :

Ingrin, Jannick [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207

Conference title :

Goldschmidt 2021

City :

Lyon

Country :

France

Start date of the conference :

2021-07-04

HAL domain(s) :

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

English abstract : [en]

Depending of their metasomatic history or geodynamic origin OH stretching bands of lithospheric pyroxenes in the frequency range 3000 – 3700 cm-1 show different signatures. Pyroxenes from continental lithosphere having ...
Show more >Depending of their metasomatic history or geodynamic origin OH stretching bands of lithospheric pyroxenes in the frequency range 3000 – 3700 cm-1 show different signatures. Pyroxenes from continental lithosphere having undergone “wet” metasomatism have distinct signature compared to continental pyroxenes having undergone “dry” metasomatism. Pyroxenes from oceanic lithosphere have a third type of signature. We present recent analyses of xenoliths and a review of the literature showing that the phenomenon is widely distributed among continents and oceans. It shows that the phenomenon affects simultaneously opx and cpx and pyroxenes from various lithologies: peridotites, pyroxenites and granulites. For instance, in continental lithosphere, OH bands at 3600 and 3415 cm-1 for opx and 3635 and 3445 cm-1 for cpx dominate pyroxenes affected by “wet” metasomatism; while OH bands at 3570 and 3515 cm-1 for opx and 3595 and 3515 cm-1 for cpx dominate pyroxenes affected by “dry” metasomatism. Opxs from oceanic lithosphere have OH spectra dominated by the band at 3415 cm-1 with a smaller contribution of the bands at 3520 and 3570 cm-1. In all these observations it was not possible to correlate the signatures with a specific major, minor or trace element and the exact nature of the signatures remains to be identified. Nevertheless, these OH signatures are representative of specific lithospheric events and offer a potential new benchmark for the study of lithospheric processes.Show less >

Language :

Anglais

Peer reviewed article :

Non

Audience :

Internationale

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 :

2021-08-10T16:13:17Z
2021-08-27T06:17:43Z