An Itinerary through Proterozoic to Holocene rocks in the North-Eastern Peloritani Mts. (Southern Italy)

During the "1st National Congress of the Italian Geological Society - Young Section" (Messina, May 2008), a geo-itinerary in the North-Eastern Peloritani Mounts, through Geosites and Geotopes testifying a Proterozoic to Holocene geological history, has been organized. The present work is a field trip guidebook of the above defined itinerary. In the first part the geo-morphological and geological characteristics of the chosen Territory, seen in the context of the Peloritani Mts. and in the wider background of the Central-Western Mediterranean Alpine Chains, have been reconstructed and illustrated. The Peloritani Mts. constitute the southern part of the complex structure known as Calabria-Peloritani Arc, located in the middle of the Mediterranean Alpine Africa-Adria vergent Orogenic System. Structured in Late Oligocene, they are made up of a pile of nine tectono-stratigraphic units which, going geometrically to the bottom and geographically to South, are: the Aspromonte, Mela, Piraino, Mandanici, Ali, Fondachelli, St. Marco d'Alunzio, Longi-Taormina and Capo St. Andrea Units. The Alpine edifice has been subsequently unconformably covered by different in type and age sedimentary deposits, from the Upper Oligocene-Lower Miocene Capo d'Orlando Flysch to the Holocene alluvial and beach deposits. The tour, which develops along a route with spectacular landscapes, involves eight Stops. It starts from Dinnammare top (1.127 m), which represents the North-Eastern limit of the Peloritani Ridge, continuing along the Tyrrhenian versant, from the Marmora Torrent mouth to the Tono Torrent mouth. It ends in Peloro Cape, on the Ionian coast. In the first five Stops, different in composition Aspromonte Unit crystalline rocks, with their geological and petrological features, document the most complex history of the Calabria-Peloritani Arc basements. The characterized sites testify Palaeo-Proterozoic to Late Oligocene plutonic and metamorphic processes (PalaeoMeso-Proterozoic tholeiitic intraplate ultramafic plutonics; Neo-Proterozoic Pan-African granulite facies metamorphics; Neo-Proterozoic-Cambrian Late-Pan-African calc-alkaline intermediate-acidic plutonics; Late Carboniferous Variscan Bosost-type L-T granulite to L-T amphibolite facies metamorphics; Late Carboniferous-Permian Late-Variscan calc-alkaline intermediate-acidic plutonics; Late Oligocene Alpine, from pervasive to soft, Barrovian-type H-T greenschist to L-T amphibolite facies metamorphics). The remaining Stops focus on some Pliocene to Modern sedimentary deposits (Early Pliocene Trubi-type marls and marly limestones; Middle Pleistocene Messina Gravels and Sands Fm.; Holocene beach deposits). In the whole Calabria-Peloritani Arc this geo-itinerary can be reconstructed only in the two sides of the Messina Straits. It allows to know the features of the oldest geological history of the Southern Sector basements of this orogen, on the basis of the macro-, meso- and microstructures, in addition to bibliographic (mostly by the same Authors) and unpublished petrological features, representative of the observed rocks. The strong structural and compositive similarities between the Aspromonte Unit Alpine partly overprinted metamorphics and the Torrox-Sayalonga Unit ones (Upper Alpujarride - Central-Western Betic Cordillera, Spain) are indicative of an analogous Pre-Alpine and Alpine evolution of the two compared basements, providing a new support to the hypothesis of the provenance of both the Calabria-Peloritani Arc and Betic Cordillera (internal units) continental crust units from a single palaeogeographic domain, recognized in the Jurassic-Cretaceous Mesomediterranean Microplate, deformed since Oligocene-Miocene.