The Mesohellenic ophiolites (MHO) in the Western Hellenides are part of an oceanic slab emplaced onto Pelagonian (Pangaean) continental rocks in the mid Jurassic with a documented NE ophiolite emplacement: the MHO root zone is probably preserved as a deep ultramafic mass within the Mesohellenic Trough. In fact, the results place the western CRB or eastern Maliac Ocean to lie at the distal southern margin (promontory) of the Eurasian craton aligned with the early- and late Paleozoic crystalline terranes: Paleozoic to Lower Triassic Variscan basement (segment of the Pelagonian Unit), "Veles Series" and Lower Complex of the Serbo-Macedonian Unit (Vertiskos Unit) ![]() The ejected Permo-Triassic, including the early Jurassic ophiolite-bearing formations of the CRB, are matched to be in line with those of the regional Southeast European importance. The terminal Vardar plate approach during the latest Jurassic - earliest Cretaceous and the convergence with the investigated portion positioned to the south of the Balkan-Hellenic foreland thrust belt configured this regional Neotethyan flysch trough, whereas the Paleocene - Eocene eastwest shortening and nappe stacking ejected the incoherent early Alpine system referred to as the CRB. A continuum between the rifting and Triassic opening of the Maliac Ocean, the Carnian EoCimmerian docking, is supported by the consolidated new data embedded into a collection of the nine distinct lithostratigraphic formations. The analysis of the stratigraphic data in combination with the highly complex, yet poorly constrained regional geology is employed to reconstruct the late Permian, Triassic, and latest Jurassic developments of this part of the southern European foreland. In the attempt to clarify the complex nature of the CRB, nine new lithostratigraphic formations (with its members) in consideration of the spatiotemporal and regional geological context are constrained by tracing the changes in regional plate interactions and linked magmato-sedimentary record. Finally, a new reconstruction of the tectonic evolution of this area was introduced and, in the context of the dispute concerning the origin of the 'ophiolitic belts' as a possible record of multiple oceanic basins, we put forward for consideration a 'single ocean' tectonic model spanning from Triassic up to Tertiary times, and valid for the whole Hellenic-Albanian sector.Ĭonsiderable debate surrounds the early-Alpine paleogeographic significance of the Circum-Rhodope belt (CRB, Greece), in particular, whether it was a rifted section of the southern Euroasian foreland, or of the late Mesozoic back-arc system of the Vardar Ocean or of both. New findings were compared with consolidated data concerning the main metamorphic events recorded in the more Internal Hellenides, geochemistry and age of the ophiolites and main stratigraphic constraints obtained in other sectors of the belt. Addressing the main debated aspects concerning the origin of the ophiolite nappe(s), the tec-tonic evolution of the Hellenic orogen was revised with a particular emphasis on the period between obduction and continental collision. ![]() In particular, the tectonic units located in Boeotia-a key area located in Central Greece at the boundary between the Internal and External Hellenides-were studied from structural, stratigraphic and biostratigraphic points of view. ![]() The aim of this paper is to contribute to deciphering the evolutionary history of the Hellenides by the study of a large sector of the chain located between the front of the ophiolitic units and the external zones classically attributed to the continental margin of Adria.
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