Timing and duration of meteoric water infiltration in the Quiberon detachment zone (Armorican Massif, Variscan belt, France) - INSU - Institut national des sciences de l'Univers Access content directly
Journal Articles Journal of Structural Geology Year : 2022

Timing and duration of meteoric water infiltration in the Quiberon detachment zone (Armorican Massif, Variscan belt, France)

Abstract

Assessing the geochemical signature and the role of fluids in a key Variscan detachment zone demonstrates the link between crustal deformation, thermo-mechanical events and Variscan mineralization. We document meteoric fluid infiltration into the ductile segment of the Late-Carboniferous Quiberon detachment zone (QDZ), when synkinematic muscovite and tourmaline crystallized and equilibrated with deuterium-depleted surface-derived fluids during high-temperature deformation. Titanium-in-muscovite thermometry supported by microstructures indicate that syntectonic isotope exchange between fluids and hydrous minerals occurred above 500 °C. 40Ar/39Ar muscovite data (∼319–∼303 Ma) and U(–Th)/Pb geochronology on zircon, monazite and apatite (∼318–∼305 Ma) from syntectonic leucogranites together with microstructural and geochemical (U and REE contents) data suggest that meteoric fluid-rock-deformation interaction started at ∼320 Ma and played a major role in leaching uranium at ∼305 Ma. U–Th/Pb data (∼330–∼290 Ma) from migmatites located below the QDZ strengthen the idea that meteoric fluid infiltration, detachment activity, syntectonic leucogranite emplacement and migmatization were coeval and allowed the development of a sustained hydrothermal system.
Fichier principal
Vignette du fichier
dusseaux-2022.pdf (7.05 Mo) Télécharger le fichier
Origin : Files produced by the author(s)

Dates and versions

insu-03576380 , version 1 (16-02-2022)

Identifiers

Cite

Camille Dusséaux, Aude Gébelin, Philippe Boulvais, Gilles Ruffet, Marc Poujol, et al.. Timing and duration of meteoric water infiltration in the Quiberon detachment zone (Armorican Massif, Variscan belt, France). Journal of Structural Geology, 2022, 156, pp.104546. ⟨10.1016/j.jsg.2022.104546⟩. ⟨insu-03576380⟩
171 View
65 Download

Altmetric

Share

Gmail Facebook X LinkedIn More