Title :

Boron isotopes as pH proxy: A new look at boron speciation in deep-sea corals using 11B MAS NMR and EELS

Author(s) :

Rollion-Bard, Claire [Auteur]
Centre de Recherches Pétrographiques et Géochimiques [CRPG]
Blamart, Dominique [Auteur]
Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] [LSCE]
Trebosc, Julien [Auteur]
Unité de Catalyse et Chimie du Solide - UMR 8181 [UCCS]
Tricot, Grégory [Auteur]
Unité de Catalyse et Chimie du Solide - UMR 8181 [UCCS]
Mussi, Alexandre [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Cuif, Jean-Pierre [Auteur]
Interactions et dynamique des environnements de surface [IDES]

Journal title :

Geochimica et Cosmochimica Acta

Volume number :

75

Pages :

1003-1012

Publication date :

2010-12-04

HAL domain(s) :

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

English abstract : [en]

Dissolved boron in modern seawater occurs in the form of two species, trigonal boric acid B(OH)(3) and tetrahedral borate ion B(OH)(4)(-). One of the key assumption in the use of boron isotopic compositions of carbonates ...
Show more >Dissolved boron in modern seawater occurs in the form of two species, trigonal boric acid B(OH)(3) and tetrahedral borate ion B(OH)(4)(-). One of the key assumption in the use of boron isotopic compositions of carbonates as pH proxy is that only borate ions, B(OH)(4)(-), are incorporated into the carbonate. Here, we investigate the speciation of boron in deep-sea coral microstructures (Lophelia pertusa specimen) by using high field magic angle spinning nuclear magnetic resonance (B-11 MAS NMR) and electron energy-loss spectroscopy (EELS). We observe both boron coordination species, but in different proportions depending on the coral microstructure, i.e. centres of calcification versus fibres. These results suggest that careful sampling is necessary before performing boron isotopic measurements in deep-sea corals. By combining the proportions of B(OH)(3) and B(OH)(4)(-) determined by NMR and our previous ion microprobe boron isotope measurements, we propose a new equation for the relation between seawater pH and boron isotopic composition in deep-sea corals. (C) 2010 Elsevier Ltd. All rights reserved.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
ENSCL
CNRS
INRA

Collections :

• Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement (LASIRE) - UMR 8516
• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Plasticité

Submission date :

2019-05-16T15:14:41Z
2021-06-24T13:43:52Z
2021-10-08T14:16:08Z