U-Pb SHRIMP-RG zircon ages and Nd signature of lower Paleozoic rifting-related magmatism in the Variscan basement of the Eastern Pyrenees
Por:
Martínez F.J., Iriondo A., Dietsch C., Aleinikoff J.N., Peucat J.J., Cires, J, Reche J., Capdevila R.
Publicada:
1 nov 2011
Categoría:
Geochemistry and Petrology
Resumen:
The ages of orthogneisses exposed in massifs of the Variscan chain can determine whether they are part of a pre-Neoproterozoic basement, a Neoproterozoic, Panafrican arc, or are, in fact, lower Paleozoic, and their isotopic compositions can be used to probe the nature of their source rocks, adding to the understanding of the types, distribution, and tectonic evolution of peri-Gondwanan crystalline basement. Using SHRIMP U-Pb zircon geochronology and Nd isotopic analysis, pre-Variscan metaigneous rocks from the Nuria massif in the Eastern Pyrenean axial zone and the Guilleries massif, 70 km to the south, have been dated and their Nd signatures characterized.. All dated orthogneisses from the Nuria massif have the same age within error, similar to 457 Ma, including the Ribes granophyre, interpreted as a subvolcanic unit within Caradocian sediments contemporaneous with granitic magmas intruded into Cambro-Ordovician sediments at deeper levels. Orthogneisses in the Guilleries massif record
Filiaciones:
Martínez F.J.:
Departament de Geologia, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
Iriondo A.:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Juriquilla 76230, Queretaro, Mexico
Dietsch C.:
Department of Geology, University of Cincinnati, Cincinnati, OH 45221-0013, United States
Aleinikoff J.N.:
U.S. Geological Survey, MS 963, Denver, CO 80225, United States
Peucat J.J.:
Géosciences-Rennes (UMR CNRS 6118), Université Rennes 1, Campus de Beaulieu, Rennes Cedex, France
Reche J.:
Departament de Geologia, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
Capdevila R.:
34120 Avenue de Bédilières, Lézignan-la-Cèbe, France
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