THE PAN-AFRICAN MICASCHISTS OF CORSICA (F RANCE) AND THEIR PALEOZOIC COVER - THEIR PLACE IN THE VARISCAN OROGEN OF SOUTHERN EUROPE

Detrital Palaeozoic formations lie unconformably on the micaschists an d amphibolites of Argentella near Galeria (Corsica); they comprise con glomerates, related to Upper Ordovician, and shales. The age of the sh ares has up to now been considered as Silurian but is now best referre d to Ashgill using new data. Shales are overlain by Upper Ordovician? glaciomarine diamictites which are topped by graptolite-bearing Llando verian lydites. The Argentella succession, which had been compared to the South-Sardinian Palaeozoic formations, must now nevertheless be co nsidered as a different one. The Argentella terrane can be interpreted as the remains of a low-metamorphic high-level unit of back-land orig in brought against the inner Variscan Corsican high-grade metamorphic basement, during a tectonic event prior to (or synchronous with) the e mplacement of earlier Mg-K plutonism around 340 Ma.