European provenance of the Numidian Flysch in northern Tunisia

Abstract

Terra Nova, 00, 1–9, 2010 The ultimate source of the deepwater Numidian Flysch sediments has long been a matter of controversy. Did the sediments of this late Cenozoic orogenic belt in the western Mediterranean derive from a European or African source, or from a combination of the two? New data presented here strongly favour a European provenance. Zircon ages of 514 ± 19 Ma from Tunisia and 550 ± 28 Ma from Sicily can only have derived from rocks of European affinity. These zircons have been separated from quartz-rich sandstones with a distinctive, highly mature heavy mineral assemblage that is different from those of North African autochthonous formations. The mature petrography and dominance of euhedral prismatic zircon grains indicate a medium to high-grade metamorphic source. Most palaeocurrent data are indicative of flow from the N and NW. The original European provenance is most likely now represented by predominantly metamorphic rocks of the Kabylie belt in northern Algeria, as a result of microplate movement and thrust emplacement.