A precise late Permian 40Ar/39Ar age for Central Iberian camptonitic lamprohyres
Abstract
The Avila batholith of central Spain is composed, predominantly, of crustal-melt peraluminous granites cut by small-scale mafic alkaline bodies. Dating of the Gredos sector mafic camptonitic lamprophyre dykes was undertaken to constrain the Late Variscan tectonomagmatic evolution of the region. A well constrained late Permian, Capitanian, age of 264.5 ± 1.3 Ma was obtained by 40Ar/39Ar geochronology using amphibole separates. This new age clearly distinguishes the dykes from other episodes of alkaline mafic magmatism in the region. We suggest that the lamprophyre dykes were emplaced into already solidified granitoids after the tectonic control on magma generation changed from purely extensional to transtensional.
Keywords
40Ar/39Ar dating. Lamprophyres. Variscan. Central Iberia. Transtension.
Full Text:
PDFDOI: https://doi.org/10.1344/105.000000346
Refbacks
- There are currently no refbacks.
This work is licensed under a Creative Commons Attribution-ShareAlike License.
Facultat de Ciències de la Terra Institut de Ciències de la Terra Institut de Diagnosi Ambiental Universitat Autònoma de Barcelona
Universitat de Barcelona "Jaume Almera" (CSIC) i Estudis de l'Aigua (CSIC)
Geologica Acta (ISSN-1695-6133)
Biblioteca de Ciències de la Terra (UB-CSIC) | Facultat de Ciències de la Terra, Martí i Franquès s/n 08028 Barcelona | Spain
Phone: +34 93 403 19 89 | E-mail: geologica-acta@ictja.csic.es
Phone: +34 93 403 19 89 | E-mail: geologica-acta@ictja.csic.es
