Dimitrios Kostopoulos

National and Kapodistrian University of Athens | uoa · Faculty of Geology and Geoenviromment

Raman elastic geobarometry has increasingly been used complementary to metamorphic phase equilibria to estimate the conditions of recrystallization in metamorphic rocks. The procedure of applying Raman elastic barom-etry to host-inclusion mineral systems requires several steps that involve various assumptions. One of the most essential assumptions...

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. Ophiolitic outliers to the east of the MHO are oceanic lithospheric fragments, not complete ophiolite bodies, preserved above exhumed Pelagonia...

We have investigated subduction‐exhumation processes in the Pelagonian zone, exposed on the Northern Sporades islands (Aegean Sea) related to successive episodes of ocean continent and continent‐continent convergence through integrating multiscale structural analysis, metamorphic petrology, and white mica ⁴⁰Ar/³⁹Ar dating. Two major progressive pha...

Pressure is one of the most important parameters to be quantified in geological problems. However, in metamorphic systems the pressure is usually calculated with two different approaches. One pressure calculation is based on petrological phase equilibria and this pressure is often termed thermodynamic pressure. The other calculation is based on con...

Carbonatitic dykes surrounded by K-Na-fenites were discovered in the Pelagonian Zone in Greece. Their carbonate portions have an isotopic mantle signature of δ¹³C and δ¹⁸O ranging from −5.18 to −5.56 (‰ vs. VPDB) and from 10.68 to 11.59 (‰ vs. VSMOW) respectively, whereas their mafic silicate portions have high Nb, Ta and ɛNd values, typical of alk...

The synmetamorphic nappe system of the Rhodope Metamorphic Complex has been deformed into dome-and-basin structures attributed to syn- to post-convergent exhumation. We document the deformation style and present new thermobarometric and geochronological constraints for the Kesebir–Kardamos dome in southern Bulgaria and northern Greece. The dome con...

The Chalkidiki block in Northern Greece represents the southwesternmost piece of the ultrahigh-pressure Rhodope and has played an important role in the evolution of the North Aegean. The eastern part of the Chalkidiki block is a basement complex (Vertiskos Unit) that is made largely of Palaeozoic granitoids and clastic sediments metamorphosed durin...

The magmatic history of the Pelagonian zone, in northern Greece, is constrained with SIMS U-Pb (SHRIMP II) dating on zircons of various granitoids whose structural positions were defined with respect to the regional main foliation. Ages pertain to four groups: (i) Meso-Proterozoic (ca. 1430 Ma) crystallization of granites inferred from inherited ma...

The Vertiskos Unit of northern Greece is an elongated basement belt with a complex poly-metamorphic history. It extends from Greece (Chalkidiki peninsula), to the south, up to Serbia, in the north, and arguably represents the westernmost part of the Rhodope Metamorphic Province (northern Greece – southern Bulgaria). The Vertiskos Unit experienced a...

We report here new LA-ICPMS detrital zircon U-Pb ages of a quartzite from the autochthon of Peloponnesus (Feneos locality), southern Greece. The rock classifies as a mature quartz arenite and belongs to an original shale-sandstone succession now metamorphosed into a phyllite-quartzite unit. Zircon age clusters at 0.52-0.75, 0.85, 0.95-1.1, 1.75-2 a...

We review published evidence that rocks can develop, sustain and record significant pressure deviations from lithostatic values. Spectroscopic studies at room pressure and temperature (P-T) reveal that in situ pressure variations in minerals can reach GPa levels. Rise of confined pressure leads to higher amplitude of these variations documented by...

Sapphirine-bearing symplectites that replace kyanite in eclogites from the Greek Rhodope Massif have previously been attributed to a high-pressure granulite-facies metamorphic event that overprinted the eclogitic peak metamorphic assemblage. The eclogitic mineralogy consisted of garnet, omphacitic pyroxene, rutile and kyanite and is largely replace...

The Circum-Rhodope Belt (CRB) sensu stricto comprises low-grade metamorphosed Triassic and Jurassic sedimentary rocks fringing the high-grade metamorphic rocks of the Serbo-Macedonian and Rhodope massifs in northern Greece. Main outcrops occur in the easternmost part of the Vardar suture zone in the Chalkidiki peninsula (Melissochori Formation; for...

The Cycladic islands of Syros and Siphnos, Aegean Sea, Greece, represent subducted IAT and BABB remnants of the Neotethyan Pindos Ocean that formed during rifting of the southern active margin of Laurussia (Pelagonia) in the mid-Triassic, in response to northward subduction of Palaeotethys. Garnet porphyroblasts (Ø=1mm) in a glaucophane-zoisite ecl...

Detrital zircon U-Pb ages of a quartzite from the Feneos locality of Peloponnesus, S. Greece, were determined by LA-ICPMS. The rock classifies as a mature quartz arenite and belongs to an original shale-sandstone succession now metamorphosed into a phyllite-quartzite unit. The latter chiefly represents the External Blueschist Belt of the Hellenides...

Abstract—Sapphirine-bearing symplectites that replace kyanite in eclogites from the Greek Rhodope Massif have previously been attributed to a high-pressure granulite-facies metamorphic event that overprinted the eclogitic peak metamorphic assemblage. The eclogitic mineralogy consisted of garnet, omphacitic pyroxene, rutile and kyanite and is largel...

We review published evidence that rocks can develop, sustain and record significant pressure deviations from lithostatic values. Spectroscopic studies at room pressure and temperature (P–T) reveal that in situ pressure variations in minerals can reach GPa levels. Rise of confined pressure leads to higher amplitude of these variations documented by...

The Mount Athos Peninsula is situated in the south-easternmost part of the Chalkidiki Peninsula in northern Greece. It belongs to the Serbo-Macedonian Massif (SMM), a large basement massif within the Internal Hellenides. The south-eastern part of the Mount Athos peninsula is built by fine-grained banded biotite gneisses and migmatites forming a dom...

The Pirgadikia Terrane in northern Greece forms tectonic inliers within the Vardar suture zone bordering the Serbo-Macedonian Massif to the southwest. It comprises Cadomian basement rocks of volcanic-arc origin and very mature quartz-rich metasedimentary rocks. U–Pb laser ablation sector-field inductively-coupled plasma mass spectrometry analyses o...

The Rhodope Massif occupies most of northeastern Greece and southern Bulgaria and comprises high-grade metamorphic rocks such as metapelites with microdiamond inclusions. The (U)HP mineral paragenesis underwent extensive metamorphic overprint at granulite-facies followed by amphibolite-facies retrograde metamorphism. A kyanite-eclogite that occurs...

Very rare rhyolite dykes cross-cutting a Miocene I-type biotite-granite were discovered on Ikaria Island in the Aegean back-arc region. Their intrusion postdates exhumation of the granite to brittle crust at about 6.0-3.6 Ma; hence a Pliocene age is inferred. Petrological, geochemical and isotopic arguments indicate an origin through melting of cru...

The Samothraki mafic suite in the north-eastern Aegean Sea, Greece, is an ‘in situ’ magmatic complex comprising gabbros, sparse dykes and basalt flows and pillows cut by late dolerite dykes. We have determined the age of the complex by SHRIMP zircon geochronology of a gabbro as 159.9 ± 4.5 Ma (i.e. Oxfordian; early Late Jurassic), which precludes a...

New geochronological and geochemical data on basement orthogneisses from the Vertiskos Unit of the Serbo-Macedonian Massif (SMM), Internal Hellenides, northern Greece, are used in order to constrain the pre-Alpine tectonic history of the basement units in the metamorphic hinterland of the Hellenides.The prevailing rock types in the Vertiskos crysta...

Uppermost Palaeozoic and Mesozoic sediments from the Vardar suture zone in northern Greece record a cycle of Neotethyan oceanic basin opening and closure and their analysis places tight constraints on the geotectonic evolution of the area. The oldest post-Carboniferous sedimentary unit in the study area is the Examili Formation, which comprises mai...

On the island of Lesvos in the north-eastern Aegean Sea, thrust sheets of mantle peridotite override a tectonic mélange containing metasediments, metabasalts and a few metagabbros. Previous workers have collectively called the above rock types the “Lesvos ophiolite” and suggested it represents Neotethyan (Jurassic) oceanic crust of N-MORB and IAT a...

The Serbo-Macedonian Massif is a basement complex in the Internal Hellenides of northern Greece, situated between the Vardar Zone to the west and the Rhodope Massif to the east. The Serbo-Macedonian Massif comprises several distinct basement units interpreted as terranes, the largest of which is the Gondwana-derived Vertiskos Terrane in the northwe...

The geology of Greece is complex. The interpretation of key ophiolitic localities of Greece has, in classic studies, aided formulation of primary models of plate tectonic theory. One of these localities, exposed along the Aliakmon River below Zavordas Monastery, was described by Jan Brunn (1908 - 2006) as the best exposure of the base of an ophioli...

Detrital zircon geochronology and analysis of fossiliferous olistoliths from Chios Island, Greece, are used here to constrain terrane accretion processes and the provenance of crustal sources for sediments during the subduction of (a branch of) the Palaeotethys Ocean. U/Pb ages obtained by ion microprobe (SHRIMP-II) analyses of detrital zircons fro...

Detrital zircon geochronology and analysis of fossiliferous olistoliths from Chios Island, Greece, are used here to constrain terrane accretion processes and the provenance of crustal sources for sediments during the subduction of (a branch of) the Palaeotethys Ocean. U/Pb ages obtained by ion microprobe (SHRIMP-II) analyses of detrital zircons fro...

In the present study we focused on detrital rutile separated from 12 psammitic samples that belong to three different sedimentary successions (Carboniferous, Permo-Carboniferous, Permo-Triassic) occurring on Chios Island, Greece. The Ti, Cr, Al, Fe, Nb, Zr, Si, and V contents of the rutiles were obtained by electron-microprobe analyses to trace the...

In the present study we focused on detrital rutile separated from 12 psammitic samples that belong to three different sedimentary successions (Carboniferous, Permo-Carboniferous, Permo-Triassic) occurring on Chios Island, Greece. The Ti, Cr, Al, Fe, Nb, Zr, Si, and V contents of the rutiles were obtained by electron-microprobe analyses to trace the...

The provenance and depositional setting of Late Palaeozoic and Early Mesozoic elastic sediments from the eastern Aegean archipelago are examined here for the first time using whole-rock geochemistry and composition of detrital chrome spinel. Major- and trace-element data for Late Palaeozoic and Permo-Triassic elastic sediments from the Lower and Up...

The Pelagonian Zone of Greece is the westernmost segment of the Internal Hellenides comprising widespread crystalline basement exposures of granites and orthogneisses. We dated these basement rocks in order to identify the major crust-forming episodes and to understand the evolutionary history of the area. In our study we investigated granites, gne...

Bauxite samples collected with permission from currently active mining areas in the Parnassos-Ghiona Mts district were studied using both conventional (optical microscopy and powder XRD) and, for the first time in the literature, micro-scale advanced non-destructive spectroscopic techniques, in particular Laser μ-Raman. The results showed that the...

The Titaros ophiolite in Greece is a coherent thrust sheet of oceanic rocks that lies atop Permo-Carboniferous granitic orthogneisses and amphibolites of unknown age of the eastern Pelagonian margin in the area NW of Mt. Olympos. It comprises a harzburgite tectonite mantle sequence with chromite mineralisation and a well-developed magma chamber wit...

The Hellenides constitute an integral part of the Alpine orogenic system in southeast Europe. Despite the recognition of several subparallel zones, which are interpreted as terranes separated by ophiolitic sutures (e. g., Pindos and Vardar sutures), the classical view of an orogen with a foreland fold-and-thrust belt, a central crystalline zone, an...

The Rhodope Massif in N. Greece is a newly established ultrahigh-pressure metamorphic (UHPM) province in the world (Mposkos & Kostopoulos, 2001). Microscopic observations on zircons separated from a garnet gneiss revealed a simple zoned structure consisting of a somewhat rounded detrital core and a metamorphic overgrowth rim. Microdiamonds were ide...

The Titaros ophiolite in Greece is a coherent thrust sheet of oceanic rocL· that lies atop Permo-Carboniferous granitic orthogneisses and amphibolites of unknown age of the eastern Pelagonian margin in the area NW of Mt. Olympos. It comprises a harzburgite tectonite mantle sequence with chromite mineralisation and a welldeveloped magma chamber with...

Bauxite samples collected with permission from currently active mining areas in the Parnassos-Ghiona Mts district were studied using both conventional (optical microscopy and powder XRD) and, for the first time in the literature, micro-scale advanced non-destructive spectroscopic techniques, in particular Laser μ-Raman. The results showed that the...

The Serbo-Macedonian Massif (SMM) is a large, elongate basement complex in the Internal Hellenides, which stretches from Serbia to the Chalkidiki Peninsula in northern Greece. As a result of similarities in lithology and structural grain, the SMM has long been considered part of the adjacent Rhodope Massif. Recent work, however, based on precise ge...

The Pelagonian Zone in Greece represents the westernmost belt of the Hellenide hinterland (Internal Hellenides). Previous geochronological studies of basement rocks from the Pelagonian Zone have systematically yielded Permo-Carboniferous ages. In this study we demonstrate, for the first time, the existence of a Precambrian crustal unit within the c...

The Vardar Zone is an integral part of the Internal Hellenides and has long been regarded as an ophiolite-decorated suture zone separating two distinct continental blocks, namely the Pelagonian Zone to the west and the Serbo-Macedonian Massif to the east. Several bodies of granites, gneisses and volcanic rocks are associated with the ophiolitic roc...

The Serbo-Macedonian Massif (SMM) is situated between the Axios River and the Strimon River in northern Greece. It is a structurally complex basement inlier between the relatively homogeneous basement complexes of the Pelagonian Zone in the west and the Rhodope in the east. The boundary to the Pelagonian Zone is by the ophiolites of the Vardar Zone...

We report here for the first time mineralogical evidence for UHP metamorphism in the Arda Unit of the central Rhodope Massif, S. Bulgaria. The present study was focused in the Chepelare area, where two units of migmatitic orthogneiss sandwich a <1 km-thick slab made up of intensely sheared migmatitic gneisses hosting lenses of grt-ky gneiss, eclogi...

Geochemically, few ophiolites have simple compositions that enable them to be assigned easily and unambiguously to a single tectonic setting. More common are complex geochemical variations in space and time that indicate a rapidly evolving tectonomagmatic environment. Some of the world's best-exposed ophiolites provide some of the best examples, no...

We report here the first discovery of ultrahigh-pressure (UHP) indicator minerals and textures from the Rhodope Metamorphic Province (RMP), northern Greece. In particular, we document the exsolution of quartz, rutile and apatite in sodic garnet from metapelites (garnet-biotite-kyanite gneisses), which attests to the presence of a Si-Ti-Na-P-rich pr...

We report here the first discovery of ultrahigh-pressure (UHP) indicator minerals and textures from the Rhodope Metamorphic Province (RMP), northern Greece. In particular, we document the exsolution of quartz, rutile and apatite in sodic garnet from metapelites (garnet–biotite–kyanite gneisses), which attests to the presence of a Si–Ti–Na–P-rich pr...

The recent discovery in northern Greece of metamorphosed crustal rocks units which had been transported to depths well within the diamond stability field provide concrete proof of a hitherto unknown UHP (ultrahigh-pressure) metamorphic event in the Aegean region (Kostopoulos et al., 2000, Mposkos and Kostopoulos, 2001). We investigated in detail th...

A low-P / high-T metamorphic event (andalusite-sillimanite series) of pre-Alpine age, identified here for the first time, has affected the metapelitic rocks of the Vernon Massif. P-T conditions of metamorphism in the western part of the Massif are estimated at -2.5 kb / 600-610°C, while in the northeastern part they are estimated to have exceeded 4...

The Rhodope Metamorphic Province represents an area of continental collision between the Balkan domain to the north and the Pangaeon domain to the south. Today, exposed astride the suture zone are Palaeozoic and Mesozoic protoliths of both continental and oceanic provenance that underwent Alpine deformation and metamorphism in a subduction zone set...

We dated basement rocks from several localities southwest of Mt. Olympos, as well as from a locality near the top of the mountain using the single zircon Pb/Pb evaporation technique. For the samples southwest of the mountain, the ages obtained range from ca. 280 to 290 Ma, with only a few zircon grains being around 300 Ma. By contrast, the sample f...

Octahedral, tetrahedral, and cubic forms of graphite, interpreted here as pseudomorphs after diamond, have been discovered in situ in crustal metamorphic rocks from central Macedonia, northern Greece. Several types of rocks, mainly of sedimentary origin, including eclogite, phyllite, quartzite, schist, and amphibolite, have been identified as hosts...

Previous detailed geochemistry of lavas from the Troodos ophiolite, Cyprus, has revealed the existence of the massif of a variety of magma types ranging in composition from island-arc tholeiites (IAT) to boninites (BSV). Petrogenetic modelling, in conjunction with field evidence, suggests that the tholeiitic types were probably derived by extensive...

Parameterization of melting phenomena in the upper mantle has primarily focused on two basic themes, namely the physical and chemical processes that govern partial melting. Parameterization of physical processes mainly refers to establishing relationships between parameters such as the temperature, pressure, matrix and melt flow geometry, lithosphe...

Detailed examination of liquidus phase relationships in binary and ternary joins of the CFMAS +Cr system has permitted a rigorous determination of the dry melting path of an initially fertile spinel peridotite composition resembling Bulk Silicate Earth or MORB-pyrolite. It is demonstrated that it is impossible to model mantle melting accurately usi...