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Simplified geological map of the west-central Balkan Peninsula, showing major tectonic zones and ophiolite occurrences. Key to lettering for different Jurassic ophiolites in the region (from north to south): Trp — Tropoja, Krb — Krrabi, Kuk — Kukesi, Puk — Puke, Skd — Skenderbeu, Blq — Bulqize, Shp — Shpati, She — Shebenik, Vo — Voskopoja, Pin — Pindos, Vou — Vourinos, Koz — Koziakas, Oth — Othris.  

Simplified geological map of the west-central Balkan Peninsula, showing major tectonic zones and ophiolite occurrences. Key to lettering for different Jurassic ophiolites in the region (from north to south): Trp — Tropoja, Krb — Krrabi, Kuk — Kukesi, Puk — Puke, Skd — Skenderbeu, Blq — Bulqize, Shp — Shpati, She — Shebenik, Vo — Voskopoja, Pin — Pindos, Vou — Vourinos, Koz — Koziakas, Oth — Othris.  

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Neotethyan suprasubduction zone ophiolites represent anomalous oceanic crust developed in older host basins during trench rollback cycles and later entrapped in orogenic belts as a result first of trench-passive margin and then continent–continent collisions. The Middle Jurassic Mirdita zone ophiolites in northern Albania constitute a critical tran...

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... NNW-trending Neotethyan ophiolites in the Balkan Peninsula occur in two distinct zones bounding the Pelagonian ribbon continent (Fig. 2). The Vardar Zone ophiolites, also known as the "Innermost Hellenic ophiolites" (Smith, 1993) or the "Eastern Hellenic ophiolites", are located east of Pelagonia and are Jurassic-Early Cretaceous in age ( Bébien et al., 1986;Mussallam and Jung, 1986;Robertson, 2002). Although most of the Vardar Zone ophiolites are highly disrupted and ...
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... Vardar Zone ophiolites separate the Pelagonian micro- continent from the Serbo-Macedonian Zone to the east, which represents the Jurassic-Early Cretaceous active margin of Eurasia (Fig. 2). Middle Jurassic calc-alkaline plutons and extrusive rocks (Chortiatis unit) in the western edge of the Serbo-Macedonian Zone constitute a magmatic arc developed along the southern margin of Eurasia ( Schunemann, 1985;Mussallam and Jung, 1986). The Paikon volcanic complex west of both the Chortiatis unit and the Guevgueli ophiolite is ...
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... ophiolites in Greece and Albania, the Mirdita ophiolites in northern Albania and their northward continuation into Kosovo and Serbia, and the Dinaric ophiolites in Bosnia and Croatia collectively form the Pindos Zone ophiolites in the Balkan Peninsula. These ophiolites show bidivergent emplacement onto Pelagonia in the east and Apulia in the west (Fig. 2). Similar to their counterparts in the Vardar Zone, they also display geochemical affinities ranging from MORB, IAT, to boninitic compositions ( Beccaluva et al., 1984;Shallo et al., 1990;Bébien et al., 1998;Clift and Dixon, 1998;Pe-Piper and Piper, 2002;Dilek and Flower, 2003), indicating subduction zone involve- ment in their ...
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... Pindos Zone ophiolites in southern Albania occur in a NW-trending belt, which makes a sharp 90° turn into a short NE-trending segment in northern Albania before it joins the NW-oriented Dinaric ophiolite belt (Fig. 2). This NE-trending short segment is known as the Mirdita zone in the literature and also corresponds to the Shkoder-Peç lineament on the tectonic map of Albania (Robertson and Shallo, 2000;). This lineament and the Mirdita zone ophiolites sharply truncate the pre-Apulian carbonate platform and flysch deposits in the Dinarides (Malesia e ...
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... lineament on the tectonic map of Albania (Robertson and Shallo, 2000;). This lineament and the Mirdita zone ophiolites sharply truncate the pre-Apulian carbonate platform and flysch deposits in the Dinarides (Malesia e Madhe and Valbona) on the west and the northeasterly turn at the edge of the Korabi-Pelagonian platform carbonates on the east (Fig. 2). Some researchers have suggested that the NE-trending Mirdita zone may represent a paleo-oceanic transform fault zone within the Pindos basin (Robertson and Shallo, ...

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... Schematic plate tectonic diagrams showing the major magmatic construction of the oceanic lithosphere, and the architecture and lithology of the various ophiolite types are shown in several recent publications (e.g., see Fig. 1 of Furnes and Dilek, 2017). Detailed information of the type-example of the various subduction-related ophiolite types can be found in Dilek (1989a, b), Thy (1998, 2009), Dilek and Flower (2003), Flower and Dilek (2003), Dilek et al. (2007), and Godfrey and Dilek (2000), Lian et al. (2020) and Yu et al. (2020Yu et al. ( , 2022. ...
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... The geochemical and isotope studies on the SE Anatolian, Tauride and Cyprus ophiolites are consistent with a supra-subduction zone origin (Pearce 1975;Dilek et al. 1990;Dilek and Eddy 1992;Dilek and Thy 1998;Dilek et al. 2007, Parlak et al. 2009Parlak 2016;2019;Robertson et al. 2012a;Karaoğlan et al., 2013 A, D;) indicating that the older NeoTethyan oceanic lithosphere was eliminated and its demise by intra-oceanic subduction generated a younger SSZ ophiolite during the Late Cretaceous (92-73 Ma) (Karaoğlan et al. 2013, Dilek and Dragged under the LO, there are two distinctly different sub-ophiolitic thrust sheets, separated by thrust faults. An ophiolitic mélange of Upper Cretaceous age, the Koçali Complex, is underlain tectonically by a flysch-wild flysch succession, the Karadut Complex (Fig 2A) (Yılmaz 1984). ...
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... S1 represents a calculated plagioclase lherzolite MORB source comprised of 0.60 oli þ0.20 opx þ0.10 cpx and S2 represents the residue (residual source) subsequent to 20% melt extraction from S1. The fields of MORB, VAB and within-plate basalt (WPB) are from Pearce (2008) and the boninite (BON) field is from Dilek et al. (2007). Abbreviations in: (b) bas-and, basaltic andesite; LU, lower unit; SIRO, subduction initiation rule ophiolite; UU, upper unit. ...
Article
The formation of chondrules involved major processes in the protoplanetary disk and therefore needs to be understood. Identifying possible precursors and the conditions of their transformation into chondrules is an essential step. Here we investigate whether refractory inclusions (RI) can be converted into Type IA chondrule analogs by isothermal heating and dynamic crystallization experiments, and report a new constraint on chondrule peak temperatures. We prepared synthetic calcium-aluminum-rich inclusions (CAI) by sintering <20 µm An + Di + Sp powder at 1200 °C and synthetic AOA analogs from crushed <5 µm Fo gel or San Carlos olivine mixed with nuggets of synthetic CAI. We used the AOA analogs as starting materials in experiments and were able to reproduce the textures and mesostasis compositions of Type IA chondrules. However, in the charges, the olivine lacks asymmetric zonation and our mesostasis compositions show olivine fractionation trends, two differences from Type I chondrules indicating the requirement of condensation of Mg and SiO in the latter. Relict spinel is present in isothermal runs up to 1550 °C, but is totally resorbed by 1600 °C. We conclude that CAI and AOA were sintered essentially at their condensation temperatures and are appropriate precursors for chondrules. Chondrules with relict spinel must have formed at <1600 °C, much lower than their liquidus temperatures (∼1750 °C). Such peak temperatures are consistent with models of condensation during chondrule formation. In typical chondrules with no inclusions of AOA or CAI, spinel is an indicator of their near complete assimilation. Grains of spinel (sensu stricto) in chondrules are relicts of RI and constitute a largely untapped cosmochemical resource for the investigation of chondrule provenance.
... Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). conditions (Kelemen et al., 1992;Barth et al., 2003;Dilek et al., 2007;Ishikawa et al., 2007). Geochemical studies of these ancient oceanic lithospheric terranes are therefore important in order to constrain the magmatic processes involved in oceanic crust genesis, i.e. partial melting, fractional crystallization and melt/fluidrock reactions (Shervais, 2001;Pearce, 2003;Aldanmaz et al., 2008). ...
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The Spontang Ophiolite complex represents the most complete ophiolite sequence amongst the South Ladakh ophiolites and comprises mantle rocks (depleted harzburgites, dunites and minor lherzolites) as well as crustal rocks (basalt, isotropic gabbros, layered gabbros etc.). In the present study, detailed geochemistry (whole rock as well as mineral chemistry) and Sr-Nd isotopic analyses of thirty-six ultramafic- mafic samples have been attempted to constraint the evolution and petrogenetic history of the Tethyan oceanic crust. Major, trace-element and REE patterns of the peridotites and their minerals indicate that the lherzolites experienced lower degrees of partial melting resembling abyssal peridotites (at higher temperatures, TREE = ∼1216 °C) than the harzburgites (6%–8% versus 15%–17%). Elevated εNd(t) and variable ⁸⁷Sr/⁸⁶Sr(t) ratios along with REE patterns suggest that the Spontang mafic rocks display N-MORB affinity with negligible participation of oceanic sediments in their genesis are originated from a depleted upper mantle with little contribution from subduction-related fluids. MORB-type Neotethyan oceanic crust is associated with the earliest phase of subduction (of older Jurassic age) through which a younger intra-oceanic island arc (Spong arc) subsequently developed. Harzburgites REE display typical U-shaped patterns, suggesting that these rocks have been metasomatized by LREE-enriched fluids. On the other side, mafic rocks are characterized by heterogeneous (Nb/La)PM and (Hf/Sm)PM and relatively homogeneous εNd(t), indicating interaction of subduction-related melts with the upper mantle during the initiation of subduction, in Early Cretaceous times.