South Portuguese Terrane: A Continental Affinity Exotic Unit

Abstract

The Paleozoic geology of Iberia is dominated by the tectonics of the Variscan orogeny and its aftermath. This defining geologic event was the result of large-scale collision that involved amalgamation of multiple continents and micro-continents, the closure of oceanic basins and eventual orogenic collapse, and finally modification and oroclinal bending during the waning stages of Pangea amalgamation. Existing data from the western Variscan orogen, suggests oroclinal bending of an originally near-linear convergent margin during the last stages of Variscan deformation occurred in the late Paleozoic. Earlier closure of the Rheic Ocean resulted in E-W shortening (in present-day coordinates) in the Carboniferous, producing a N-S trending, east verging belt. Subsequent deformation near the Carboniferous-Permian boundary resulted in oroclinal bending. This late-stage orogenic event remains an enigmatic part of Iberia’s Paleozoic history.