Peri-Amazonian provenance of the Proto-Pelagonian basement (Greece), from zircon U–Pb geochronology and Lu–Hf isotopic geochemistry

摘要: Abstract The basement of the Pelagonian zone Hellenides, in Eastern Mediterranean realm, has been shaped by mid-Neoproterozoic (700 Ma) and Variscan (300 Ma) igneous activities. In present study, detrital zircon U–Pb geochronology Lu–Hf isotope geochemistry ca. 700 Ma-aged granites pre-700 Ma metasediments from allow a genuine perspective into provenance origin this terrane which hosts one oldest sedimentary sequences known SE Europe. crustal vestiges comprising 700 Ma granitoids their hosting are termed here “Proto-Pelagonian”. Except several concordant Tonian-aged grains (as young as 980 Ma), set Early Tonian maximum sedimentation age, preponderance separated four Proto-Pelagonian metasedimentary samples yielded Mesoproterozoic–Paleoproterozoic ages peaking at 1.5 Ga. Neoproterozoic-aged generally absent. isotopic data is thus consistent with an Amazonian source for sequence. terms age spectra, exhibit close similarity to pre-Avalonian (e.g. Gamble Brook Formation) underlie Late Neoproterozoic "typical Avalonian" successions Atlantic Canada. signal obtained however markedly different that previously African-derived terranes imbricated region usually devoid Mesoproterozoic (other than Stenian). Likewise, also differs Avalonian-type identified Mediterranean–SE European (Istanbul block Pontides, Pirgadikia Internal Hellinides, North Central Dobrogea Danubian basement), alongside abundant contain zircons. Thus, point view pre-Variscan geological history, exotic respect surrounding both, African Avalonian origins.