118 / 352
5. PROVENANCE OF THE UPPER ALLOCHTHON
102
as to have an activity bracketed between 750 Ma and 540 Ma, and so it
could represent a long lasting volcanic
–
magmatic arc system.
Taking into account the Nd TDM model ages published from other
metagreywacke series included in the NW Iberian Upper Allochthon,
it can be concluded that this terrane contains heterogeneous isotopic
sources. These varied sources indicate that different parts of the peri-
Gondwanan arc system may be preserved in the Upper Allochthon.
Acknowledgements
Financial support for this research has been provided by the Spanish
project CGL2012-34618 (Ministerio de Economía y Competitividad).
The authors are grateful to Wilfried Winkler and David Orejana who
performed insightful reviews of the manuscript and to Inna Safonova
for the excellent editing work. R. Albert is thankful to the Universidad
Complutense de Madrid which provided him with a pre-doctoral
grant. Theauthorsarealsothankfulforthetechnicalandlaboratorysup-
port provided by Linda Marko (GUF) and José Antonio Hernández
Jiménez (UCM).
Appendix A. Supplementary data
Supplementary data to this article can be found online at
http://dx.
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