Early Paleozoic U-Pb age of zircons from metagranophyres of the Grand-Saint-Bernard Nappe (zona interna, Aosta Valley, Italy).

Authors
Bertrand, JM Guillot, F Leterrier, J
Citation
Jm. Bertrand et al., Early Paleozoic U-Pb age of zircons from metagranophyres of the Grand-Saint-Bernard Nappe (zona interna, Aosta Valley, Italy)., CR AC S IIA, 330(7), 2000, pp. 473-478
Citations number
30
Categorie Soggetti
Earth Sciences
Journal title
COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE II FASCICULE A-SCIENCES DELA TERRE ET DES PLANETES
ISSN journal
12518050 → ACNP
Volume
330
Issue
7
Year of publication
2000
Pages
473 - 478
Database
ISI
SICI code
1251-8050(20000415)330:7<473:EPUAOZ>2.0.ZU;2-N
Abstract
The U-Pb age of a metagranophyre from the Val de Rhemes (Brianconnais basem ent of the Aosta Valley) of 511 +/- 9 Ma suggests that the micaschists whic h dominate the pre-alpine basement of the Grand-Saint-Bernard Nappe are, in part, of Early Paleozoic age. The Brianconnais domain is characterized by a Cambrian to Ordovician alkaline to subalkaline (monozonitic) magmatism, s imilar in age to orthogneisses known in other parts of the Variscan belt an d generally interpreted as related to an extensional event. (C) Academie de s Sciences / Editions scientifiques et medicales Elsevier SAS.