Abstract
The allochthonous complexes of NW Iberia can be correlated with the paleogeographic realms involved in the Variscan collision. Assuming that the existing ophiolites represent the suture formed by the closure of a Paleozoic ocean, the units in the footwall to the suture correspond to the outer edge of the Gondwana continental margin, formed after the opening of the ocean. The units in the hangingwall to the suture are interpreted as pieces of a continental fragment detached from Gondwana, which registered an orogenic event in the Lower Ordovician, shortly after its separation. The correlation establishes a link between circum-Atlantic terranes and the Rheic ocean, and makes it possible to draw a relatively simple scenario of the successive recorded tectonothermal events. Following the amalgamation of Avalon to Laurentia, the remaining outboard terranes underwent a progressive accretion to the Laurentian continental margin that ended with the collision between this continent and Gondwana. The accretionary history, as deduced from the tectonothermal events recognised mainly in the Galician allochthonous complexes (NW Spain), includes partial subduction of the continental margin of Gondwana, during the Middle Devonian.
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Martínez Catalán, J.R., Arenas, R., Díaz García, F., Abati, J. (1999). Allochthonous Units in the Variscan Belt of NW Iberia: Terranes and Accretionary History. In: Sinha, A.K. (eds) Basement Tectonics 13. Proceedings of the International Conferences on Basement Tectonics, vol 7. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-4800-9_5
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DOI: https://doi.org/10.1007/978-94-011-4800-9_5
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