Emplacement of the Lavadores granite (NW Portugal): U/Pb and AMS results

• Type: Article in International Scientific Journal
• Date: 2011

Authors

Helena C B Martins (Author) FCUP; Helena Sant'Ovaia (Author) FCUP; Joana Abreu (Author) Other; Miguel Oliveira (Author) Other; Fernando Noronha (Author) FCUP

Journal

Title: Comptes Rendus - Geoscience

Vol. 343 No. 6

Pages: 387-396

ISSN: 1631-0713

Publisher: Academie des Sciences

Indexing

ISI Web of Knowledge - 23 Citations

ISI Web of Science

Scopus - 27 Citations

Scientific classification

FOS: Natural sciences > Earth and related Environmental sciences

CORDIS: Natural sciences

Other information

Authenticus ID: P-002-QM1

DOI: 10.1016/j.crte.2011.05.002

Abstract (EN): Studies of Anisotropy of Magnetic Susceptibility (AMS) and U-Pb geochronology, in zircon fractions, were carried out in a magnetite type-granite, the Lavadores granite, which is an example of a late to post-orogenic Variscan granite in northern Portugal (NW Iberian Peninsula). The U-Pb zircon analyses yield an age of 298 +/- 11 Ma that is considered to be the emplacement age of this granite and thus suggesting a post-tectonic emplacement. This is also supported by the magmatic nature of the microstructures. Magnetic lineations are subvertical and magnetic foliations display a general WNW-ESE subvertical pattern consistent with a dextral kinematic. These AMS data suggest that the emplacement of the Lavadores granite was controlled by a major mechanical anisotropy formed by transtensional structures associated with the Porto-Tomar shear zone.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10