%0 Journal Article %T First-report on Mesozoic eclogite-facies metamorphism preceding Barrovian overprint from the western Rhodope (Chalkidiki, northern Greece) %+ Géosciences Rennes (GR) %+ Institut des Sciences de la Terre %+ National Technical University of Athens [Athens] (NTUA) %+ Faculty of Geology and Geoenvironment %A Kydonakis, Konstantinos %A Moulas, Evangelos %A Chatzitheodoridis, Elias %A Kostopoulos, Dimitrios %A Brun, Jean-Pierre %< avec comité de lecture %Z PL03418 %@ 0024-4937 %J Lithos %I Elsevier %V 220-223 %P 147-163 %8 2015 %D 2015 %R 10.1016/j.lithos.2015.02.007 %K isochemical phase diagrams %K Aegean %K Serbo-Macedonian %K garnet-staurolite schists %K high-pressure low-temperature metapelites %K eclogite %Z Sciences of the Universe [physics]/Earth SciencesJournal articles %X The Chalkidiki block in Northern Greece represents the southwesternmost piece of theultrahigh-pressure Rhodope and has played an important role in the evolution of the NorthAegean. The eastern part of the Chalkidiki block is a basement complex (Vertiskos Unit) thatis made largely of Palaeozoic granitoids and clastic sediments metamorphosed during theMesozoic. This basement is traditionally considered as part of the Rhodopean hanging-wall,an assignment mainly supported by the absence of high-pressure mineral indicators and thepresence of a regional medium-pressure/medium-temperature amphibolite-facies Barrovianmetamorphic imprint. Toward the west, the basement is juxtaposed with meta-sedimentary(Circum-Rhodope belt) and arc units (Chortiatis Magmatic Suite) that carry evidence of aMesozoic high-pressure/low-temperature event. In this study, garnet-staurolite-mica schistsfrom the eastern part of the basement were examined by means of micro-textures, mineralchemistry and isochemical phase-diagram sections in the system NCKFMASHMn(Ti)[Na2O-CaO-K2O-FeO-MgO-Al2O3-SiO2-H2O-MnO-(TiO2)]. The schists represent formerMesozoic sedimentary sequences deposited on the Palaeozoic basement. We document thepresence of a relict eclogite-facies mineral assemblage (garnet + chloritoid + phengite +rutile) in an amphibolite-facies matrix composed of garnet + staurolite + phengite ± kyanite.Model results suggest the existence of a high-pressure/medium-temperature metamorphicevent (1.9GPa / 520°C) that preceded regional re-equilibration at medium-pressure/mediumtemperatureconditions (1.2GPa / 620°C). Clearly, the eastern part of the Chalkidiki block(basement complex) retains memory of an as yet unidentified Mesozoic eclogiticmetamorphic event that was largely erased by the later Barrovian overprint. In the light of ourfindings, the basement complex of the Chalkidiki block shares a common tectonometamorphicevolution with both the high-pressure units to the west, and the high-gradeRhodopean gneisses further to the northeast. Our results are consequential for the geodynamic reconstruction of the Rhodope since they require participation of the Chalkidikiblock to the well-established Mesozoic subduction system. %G English %2 https://insu.hal.science/insu-01117877/document %2 https://insu.hal.science/insu-01117877/file/Kydonakis-lithos-2015.pdf %L insu-01117877 %U https://insu.hal.science/insu-01117877 %~ INSU %~ UNIV-RENNES1 %~ UR2-HB %~ CNRS %~ GR %~ OSUR %~ UR1-HAL %~ UR1-SDLM %~ UR1-SDLMJONCH %~ GR-3T %~ UNIV-RENNES2 %~ TEST-UNIV-RENNES %~ TEST-UR-CSS %~ UNIV-RENNES %~ INRAE %~ UR1-ENV