Pre-Triassic history recorded in the Calabria-Peloritani segment of the Alpine chain, southern Italy. An overview.

Abstract

— Clockwise P-T-(t) trajectories are generally recorded in the pre-Triassic basement rocks of the Calabria-Peloritani segment of the Alpine chain. Geochronological data point to a synchronism of T-peak and emplacement of huge masses of granitoids at about 300 Ma. Decompression and heat supply from the granitic intrusions mark the transition from Barrovian to low P/high T metamorphism. When the preserved characters allow to trace prograde trajectories, a strong Pincrease and a moderate T increase, sometimes with T peak delayed relatively to the P peak. These features are consistent with orogenic evolution in which crustal thickening in early-middle-Hercynian contractional stages was followed by crustal thinning in late-Hercynian extensional stages. Moreover, in the Calabria-Peloritani segment of the Alpine chain, pre-Hercynian metamorphic and magmatic evidence also occurs