S Journal of

O p s e s n Acce Geology and Geoscience

Review Article The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine : Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Adamantios Kilias* Aristotle University of ,

Abstract We present the main geological structure and architecture of the Hellenic orogenic belt, suggesting a new approach about its geotectonic evolution during the . The structural evolution starts with the continental rifting of the Pangaia Super-continent during the Permo-Triassic and the birth of the Neotethyan ocean realm. Bimodal magmatism and A-type granitoide intrusions associate the initial stages of the continental rifting followed by Triassic- multiphase shallow- and deep-water sediments deposition on both formed continental margins. They margins were, the Apulian margin at the western part of the Neotethyan ocean (containing the Pelagonian) and the European margin at the eastern part of the Neotethyan ocean, containing the (Serbo-Macedonian massif and continental parts of the nappes). Deformation and metamorphism are recorded in six main deformational stages from the Early-Middle Jurassic to present day, getting started with an Early-Middle Jurassic Neotethyan intra-oceanic subduction and island arc magmatism. Compression, nappe stacking, calc-alkaline magmatism and high-pressure metamorphism related to subduction processes alternated successively through time with extension, orogenic collapse, medium- to high-temperature metamorphism, adakitic and calc-alkaline magmatism and partly migmatization, related to uplift and exhumation of deep crustal levels as tectonic windows or metamorphic core complexes. An S- to SW-ward migration of the dynamic peer compression vs extension is clearly recognized during the Tertiary Alpine orogenic stages in the Hellenides. In any case extension and crustal uplift follow compression and nappe stacking or compression and extension act simultaneously at different parts of the orogen. We suggest that all belts in the Hellenides originated from a single source and this was the Neotethyan Meliata-Axios/Vardar ocean basin, obducted during the Late Jurassic on both, Apulian`s (e.g. Pelagonian) and European`s continental margins (e.g. Serbo-Macedonian), East and West of the Axios/Vardar ocean realm, respectively. In this case the ophiolite nappes should be considered as far-travelled nappes on the Hellenides continental parts associated with deposition of Middle- to Late Jurassic ophiolitic mélanges in basins at the front of the adjacent ophiolite thrust sheets. The upper limit of the ophiolite emplacement is the Upper Jurassic, Kimmeridgian/Tithonian, as it is showed by the deposition of the Kimmeridgian/Tithonian Upper Jurassic sedimentary carbonate series on the top of the obducted ophiolite nappes. The Axios/Vardar ocean closed finally during the Late Cretaceous-Paleocene subducted totally under the European continental margin. The suture zone between the Pelagonian nappe and the External Hellenides as part of the Apulia plate has been dated about coeval in time with the Paleocene-Eocene overthrusting, along the thrust zone, of the Rhodope Sidironero and Kimi units and the equivalent to these Serbo-Macedonian Kerdylia and Vertiskos units respectively, on the tectonically lower-most Rhodope Pangaion unit. The lower-most Rhodope Pangaion unit is regarded, for first time, as the marginal part of the Apulian`s origin Pelagonian segment that was overthrusted during the Paleocene-Eocene by the European`s origin Serbo-Macedonian and Rhodope nappes, following the Axios/Vardar ocean finale closure. Subsequently, the lower-most Pangaion Rhodope unit exhumed as an Oligocene- metamorphic core complex below the Serbo-Macedonian and Rhodope nappes, which exhumed successively from the Late Cretaceous-Paleocene to the Eocene-Oligocene. In this scenario one should be assumed, that the true Vardar/Axios suture zone should be originated in the deep further to the East in the Rhodope province along the northern boundary of the Rhodopes with the Strandja/Sredna-Gora massifs (). A retreating subduction zone and roll back of the subducted lithospheric slab under the Pelagonian and the other Internal Hellenides nappes stack and/or mantel delamination could well explain the Tertiary extensional tectonics in the Internal Hellenides, taken place simultaneously with compression in the External Hellenides and the Hellenic vorland or accretionary wedge. Keywords: Hellenides, compression, extension, geotectonic,

Correspondence to: Adamantios Kilias, Aristotle University of Thessaloniki, Greece. E-mail: kilias[AT]geo[DOT]auth[DOT]gr

Received: March 29, 2021; Accepted: April 09, 2021; Published: May 04, 2021

J Geol Geosci 1 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Introduction Neotethyan Meliata-Axios/Vardar ocean basin. In this case, all ophiolite belts which crop out in the Hellenides, east and The Hellenides form a branch of the broader Alpine orogenic west of the Pelagonian and the Serbo-Macedonian/Rhodope belt in . It was resulted from the convergence and final province, originated from the Meliata-Axios/Vardar ocean continental collision of the European and Apulian plates in basin. They were obducted on the Pelagonian and Serbo- a complicated, multiphase deformational regime, with the Macedonian continental margins during the Late Jurassic with questions around, the existence of one or more Mesozoic Tethys a W-ward and E-ward movement direction respectively [22- ocean basins between European and Apulian continents (e.g. 26,5-8,11,13,27-30,16,18]. Meliata-Axios/Vardar ocean, Pindos/Mirdita ocean etc) and the paleogeographic and tectonic origin of the old Paleozoic, On the contrary, other researchers propose that the Axios/Vardar pre-Alpine crystalline Pelagonian and Serbo-Macedonian/ ocean basin was a narrow basin between the Pelagonian micro- Rhodope fragments with their Triassic-Jurassic sedimentary continent in the west and the Serbo-Macedonian/Rhodope cover incorporated in the Hellenides to remain under debate province in the east, operating about simultaneously during until today (e.g. critical element on these questions is the the Triassic-Jurassic with a second, Pindos/Mirdita ocean geotectonic position of the lower most Rhodope Pangaion that was situated western of the Pelagonian micro-continent unit) Several geotectonic models have been suggested until and eastern of the Apulian plate [2,31-35,17]. Alternatively, today [1-22,30]. the Axios/Vardar basin is also viewed as just a small ocean, part of a series of narrow ocean domains extending in the Fig1. middle of small continental blocks between Apulia and Europe More specifically, some authors suggest that only one main continents [36,147,17]. In any case, according to any of those ocean-basin opened during the Triassic-Jurassic, situated scenarios, the Hellenides’ ophiolite belts derive from more eastern of the Apulian (including the Pelagonian) and western than one ocean basins with different Late Jurassic to Early of the European (including the Serbo-Macedonian and the Cretaceous emplacement directions, mainly top-to-the-West Rhodope nappes) continental margins and it corresponds to the and/or top-to-the-East [2,35-41,147,17,19].

Figure 1: The main structural domains of Dinarides and Hellenides as parts of the broader Alpine orogenic belt in Europe. Insert: The Alpine orogenic belt in Europe and the Tertiary extensional basins in the Mediterranean region (modified after Kilias et al. 2010).

J Geol Geosci 2 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Fig2. Recent works [30,15,22,42-43] suggest a new theory, so- called the “maximum allochthony hypothesis”. According to Additionaly, Papanikolaou (2009, 2013) descripts a different that, all the ophiolite belts of the Hellenides are allochthonous, geodynamic evolution for the Hellenides according to that, a number of Triassic-Jurassic to Cretaceous Tethys oceanic terranes originated from one main Triassic-Jurassic ocean rooted along existed between several continental terranes of origin the northeastern border of the Rhodopes and the south western and various dimensions drifting to the North. The timing of the margin of the Europe. The Axios/Vardar ocean closed finally opening and closure of each one oceanic terrane and the tectonic during the Late Cretaceous-Paleocene subducted totally under emplacement of the ophiolites was different. The oceans closure the European margin and the Late Cretaceous Sredna-Gora and the ophiolite obduction procedure on top of the pre-Alpine magmatic arc. Furthermore, the Pindos ocean is regarded as continental terranes become younger from the Northeast towards a narrow ocean basin operating western of the Pelagonian Southwest (Mid-Late Jurassic to Late Eocene-Oligocene) with a block during the Late Cretaceous and closed in the Paleocene- main towards-SW ophiolites emplacement direction. Eocene, when subducted completely under the Pelagonian

Figure 2: Geological map of the Hellenides with the main tectonic zones and their possible continuation to the East in . (modified after Jolivet et al. 2004, Okay et al. 2012, Kilias et al. 2013, Schmid et al. 2020).

J Geol Geosci 3 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis segment. The lower-most Rhodope Pangaion unit belongs to • Internal Hellenides: I. Pelagonian zone or nappe and the External Hellenides and the Apulian plate, exhumed during ?Parnassus zone II. ?Sub-Pelagonian zone, III. Axios/ the Oligocene-Miocene as a metamorphic core complex below Vardar zone, IV. Cycladic massif, V. Circum-Rhodope the over thrusted European nappes. The goal of this work was belt, VI. Serbo-Macedonian massif, VII. Rhodope to present our one aspect about the structural architecture massif. and geodynamic evolution of the Hellenides, as well as the The External Hellenides are mainly built up by Mesozoic origin of the pre-Alpine continental blocks incorporated in the and deep-see and shallow water sedimentary Hellenic orogenic belt. We based on our recent studies and rocks, characterized by continuous sedimentation processes experience about the deformational history of the Hellenides terminated with a Paleocene to Miocene flysch deposition. but also on the more modern views, published from others They form a complicated SW- to SSW-verging, thin-skinned colleagues, concerning the Alpine geotectonic reconstruction thrust and fold belt of Paleogene to Neogene age, without any of the Hellenides. important metamorphism; and references therein [44-48]. Geological-Geotectonic Setting Fig3. Today, the Hellenides form an arcuate type orogenic belt On the other hand, the Internal Hellenides are composed by extending from Dinarides to Taurides, traditionally subdivided Paleozoic and older basement rocks covered by Triassic- into the External and Internal Hellenides zones. Maintaining Jurassic carbonate platform sediments, as well as outer shelf the old subdivision of the Hellenides in isopic zones [44-45], and shelf edge sedimentary series, on which the Neotethyan the External and Internal Hellenides are composed, from the ophiolites realm were initially obducted during the Late west to the east, by the following main tectonostratigraphic Jurassic. Internal Hellenides are characterized by a multiphase domains. tectonic history and metamorphism during the Alpine orogeny, • External Hellenides: I. Paxos zone, II. Ionian zone, III. from the Jurassic to the Tertiary (D1 to D6 events; they are in Gavrovo zone and IV. Pindos zone, possibly including detail described in the chapter “Architecture of deformation the Koziakas unit. and structural evolution). The Internal Hellenides overthrust

Figure 3: Geological map of Northern Greece compiled after Schermer (1993), Kilias (1995, 1991, 2018, 2019), Ring et al. (1999), Bozkurt and Oberhaensli (2001), Brown and Robertson (2003, 2004), Rassios and Moores (2006), Bonev et al. (2006, 2015), Rassios and Dilek (2009), Kilias et al. (2010, 2013, 2015), Robertson et al. (2013), Katrivanos et al. (2013), Meinhold and Kostopoulos (2013), Froitzheim et al. (2014), Michail et al. (2016), Oner Baran et al. (2017). Qu=Quaternary, Ne=Neogene, Mi=Miocene, Ol=Oligocene, Eoc=Eocene, Pal=Palecene, Cr=Cretaceous, Jr=Jurassic, Tr=Triassic, Pm=Perm, Pa=Paleozoic and older, L=Late, E=Early. A-A` cross-sections in Fig. 4.

J Geol Geosci 4 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis during the Eocene-Oligocene the External Hellenides [49- compositional features of the Hellenides tectonostratigraphic 63,5,16-17,19]. domains. A Paleocene-Eocene high-pressure belt characterizes the Fig5. tectonic contact between External and Internal Hellenides External Hellenides zones exhumed in the Olympos-Ossa and provinces direct under the Internal Hellenides Pelagonian nappe [64- Paxon Zone 70,51-53]. The Paxon zone form the most external zone of the External Another, high-pressure/low-temperature metamorphic belt Hellenides continued to the North in the Albanides and (HP/LT) of Oligocene-Miocene age is also recorded inbetween Dinarides. It is characterized by a continuous, neritic carbonate the lithostratigraphic domains of the External Hellenides, in sedimentation from the Upper Triassic to the Oligocene- the Plattenkalk, Phyllite-Quartzite and Tripali units, which are Miocene without any typical flysch deposition, which is well exhumed in the southern and island [71- exposed in all the others external Hellenides zones. Thinn strata of siliceous sediments and shales are locally interbedded with 76]. Additionally, high- to ultrahigh-pressure metamorphic the Jurassic carbonate succession. Furthermore, evaporites are conditions of Jurassic/Cretaeous and Eocene age are also the older, lower most litho-stratigraphic sequence of the zone described for the Serbo-Macedonian/Rhodope metamorphic [45,102-107,21]. province of the Internal Hellenides [77-86]. Recently works, recognize a Late Cretaceous high-pressure belt in the Rhodope Ionian Zone province [87,43]. The Ionian zone is built up by a continuous sedimentatary Fig4. series from the Triassic to the Oligocene-Miocene. It is also recognized to the North in the Albanides and Dinarides orogenic Late orogenic Paleocene to Early Miocene molassic-type belts. Until the Early-Middle Liassic, the sedimentation was (turbidites) basins, such as the Mesohellenic trough [44,88- characterized by neritic calcareous deposits, terminated with 91,58] and the Thrace basin [92-94,6-8,59-61] were developed the characteristic Pantokratora white limestones series of locally on the top of the External and Internal Hellenides Liassic age. On the contrary, from then until the Eocene the structural sequences. Finally, post orogenic Neogene- sedimentary conditions changed to pelagic with radiolarites Quaternary intramontagne and other terrestrial sedimentary and pelagic limestones deposition and finally ended with an basins cover unconformably in many places, all the pre-Alpine Oligocene-Miocene flysch deposition. As in the Paxon zone, and Alpine Helenides tectono-stratigraphic domains [95-101]. evaporites are also the older, lower most litho-stratigraphic In the next are briefly described the main structural and sequence of the Ionian zone [44-45,59-61].

Figure 4 a and b: Representative geological cross-sections through northern Greece, showing the geometry of deformation and structural architecture of the Hellenic orogenic belt, as it is created by the Alpine orogenic processes from the Jurassic to the recent (The deformational events are in detail described in the chapter “Architecture of deformation and structural evolution”). The tectonic windows of Olympos-Ossa and Rhodope Pangaion are shown. MHT= Mesohellenic trough. Legend and abbreviations as in Fig. 3 (modified after Kilias 2018, 2019, Kilias et al. 2013). 26-10Ma=cooling ages of the several Serbo-Macedonian/Rhodope province`s tectonic nappes (Wuethrich 2009).

J Geol Geosci 5 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 5: Schematically, the tectonostratigraphic column of the Hellenides. The several Alpine deformational events and their action are shown (They are in detail described in the chapter “Architecture of deformation and structural evolution”). Abbreviations as in Fig. 3.

Equivalent to the Ionian sediments seems to be the Plattenkalk to Eocene neritic, platform sedimentation on the Apulia unit in the Peloponnese and Crete island, cropping out basement, terminated by the deposition of a Late Eocene- tectonically together with the Tripali unit under the Phyllite- Early Oligocene flysch [44-45,113-114,59-61]. It is also Quartzite unit and the Gavrovo zone [108-110,72-74]. The exhumed northern in the Albanides and Dinarides. The Plattenkalk, the Tripali and the Phyllite-Quarzite units have western parts of the Gavrovo zone in External Hellenides been affected by the Oligocene-Miocene HP/LT metamorphic appear unmetamorphosed. However, its more eastern parts event of the External Hellenides, mainly recognized in Crete that crop out in Internal Hellenides as tectonic windows or and Peloponnese. The Plattenkalk are rich in metamorphic metamorphic core complexes in Olympos-Ossa, Rizomata, aragonite in the marbles and Fe-Mg-carpholite in the Almyropotamos- and Cyclades provinces, beneath the intercalated metabauxites. In the Phyllite-Quartzite unit has Pelagonian nappe and the glaucophane-bearing Paleocene- been recognized glaucophane associated also with Fe-Mg- Eocene high-pressure blue-schists belt, show evidence of a carpholite. The Plattenkalk and the Phyllite-Quartzite units Tertiary low- to high-grade metamorphism and possibly an HP/ were uplifted rapid under extensional tectonics and isothermal LT metamorphism. In Olympos-Ossa province the exhumation decompression of Early-Middle Miocene age [71,110-111,72- of the blue-schists belt took place rapid under extension, 76], The Ionian zone is thrusted over the Paxos zone towards isothermal decompression and low grade retrogration of west during the Mid-Miocene. Oligocene-Miocene age without a significant reheating [51- 53,115-116,67-69,4]. Οn the contrary in the Cyclades the P-T Fig6. metamorphic path and the exhumation of the blue-schists belt Gavrovo Zone are also characterized by extensional tectonics but significant The Gavrovo zone is characterized by a continuous Triassic reheating, high-temperature metamorphism, migmatization

J Geol Geosci 6 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 6 a: P-T-t tectono-metamorphic path and exhumation history of the Oligocene-Miocene high pressure belts (Plattenkalk, Tripali and Phyllite- Quartzite units) in Crete island (Kilias et al. 1994, Thomson et al. 1998). b. Field- and macroscale photos of the geological units and deformational structures in the Crete island (I to IX). Explanations are separately given on each photo. Sense of shear is shown by arrows and it is related to the Early- Middle Miocene extension and exhumation of the Oligocene-Miocene HP/LT metamorphic belt of the External Hellenides (Peloponnesus and Crete).

J Geol Geosci 7 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis and abundant granitoides intrusions during the Oligocene- continued further to the East in western Turkey in the Menderes Miocene [117-125,65]. metamorphic core complex as its deeper structural level [128- 129,9]. Both, Cyclades and Menderes provinces show at Fig7. least, an equivalent tectonostratigraphic setting and Tertiary The pre-Alpine basement of the Gavrovo carbonate platform tectonic history. From the bottom to the top is recognized, a (Apulia plate) is exhumed as metamorphic core complexes pre-Alpine basement covered by Triassic to Eocene neritic in the Cyclades province beneath the Gavrovo carbonate limestones or marbles in places, (and they are the Gavrovo series and the overlain Pelagonian nappes and the obducted carbonate platform), overthrusted by the Paleocene-Eocene Neotethyan ophiolites [119,126-131,9,123]. It is possibly Cycladic/Olympos-Ossa high-pressure belt. Triassic granitoids

Figure 7: Geological-structural map and representative cross-section of the eastern tectonically boundary of the Pelagonian nappe with the Axios/Vardar zone at Vermion and Mts. The Rizomata window, equivalent to the Olympos-Ossa window, as well as the Late Jurassic tectonically duplication of the Pelagonian nappe and the Paleocene-Eocene Almopian tectonic sheets are shown (based on Kilias and Mountrakis 1989, Schenker et al. 2014, 2105). Abbreviations as in Fig. 3.

J Geol Geosci 8 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis intrusions in both provinces is another common point of these. clastic neritic sediments of Early-Middle Triassic age, with Oligocene-Miocene granitoids intrusions occur also in both volcanoclastic products intercalations. An occurrence of the Menderes and Cyclades domains but in different amount. Early Cretaceous flysch-type deposits (Pindos “first flysch”) in between the deep water Pindos strata remains until today Fig8. under debate. They are composed of alternations of thin layers They are more in the Cyclades massif [119,132-137,128- of red marls and radiolarian cherts, marly limestones, pelites 129,40-41,130]. Furthermore, kinematic indicators show and green fine to coarse-grained sandstones with ophiolitic really similarities in both areas of Cyclades and Menderes. material, as well as ophiolite pebbles. The Pindos zone is In the Cyclades the Oligocene-Miocene extension`s direction continued also to the North in the Albanides and Dinarides evolves mainly N- to NE-wards and is related to exhumation orogenic belts [44-45,59-61]. processes, as it is also described for the Menderes region. The geotectonic position of the Pindos zone is widely Additionally, S- to SW-wards sense of movements have controversial. It is believed to be either an ocean basin opened been also described for both areas, respectively [119,138- progressively due to the Permo-Triassic continental rifting of 142,132,128-129,9-10,123]. [44,2,36-37,147,40-41,17] or a deep basin formed Nevertheless, some lithological and structural differences on thinned continental crust. Moreover, recent works by should be referred here between the two regions, leaving some [30,15,21-22,42-43] suggest the opening of a narrow ocean question marks on the correlation of the two areas and raising basin during the Late Cretaceous, named Pindos-Cyclades the need for the requirement of a further more detail research ocean, divided the Pelagonian of the Apulia at this time. This for the correct answer. An important difference is the absence, ocean as part of the entire Pindos zone was totally subducted in the Menderes metamorphic core complex, of the Pelagonian during the Paleocene-Eocene under the Pelagonian fragment nappes above the Paleocene-Eocene Cycladic blue schist’s and the Internal Hellenides nappe stack. The Pindos zone is belt, maybe it is totally eroded and tectonically denuded during in a similar structural position as the Paleocene-Eocene blue- the exhumation stages of the Menderes massif. Above the schists belt in the Olympos-Ossa and Cyclades provinces, blue schists in the Menderes massif are tectonically lying the tectonically directly above the Gavrovo zone. It possibly Lycian nappes taking the same position with the Pelagonian represents in the External Hellenides the non-metamorphic nappes in the Cyclades and in the Hellenides. Moreover, the equivalent of the Paleocene-Eocene high pressure belt that Menderes basement has been not affected by the Ercynian has escaped the subduction under the Pelagonian continental orogeny and absents from it the Carboniferous age’s granitoids fragment [108,149-150,21,5,58,28]. On the contrary, [32- intrusions (300Ma) dominated in the Hellenides basements 33] regard the blue-schists belt as of Pelagonian origin. [143-144,2,8]. The Menderes basement forms a -African Additionaly, the Pindos zone is thrusted on the Gavrovo zone continental segment [138,132,145,128-129,140,141]. One towards west during the Eoecene-Oligocene about the same more difference is the obduction age of the ophiolites. In the time with the overthrusting of the Paleocene-Eocene high- Hellenides it is of Late Jurassic age in the Menderes massif of pressure belt and the Pelagonian nappe on the Olympos-Ossa Late Cretaceous age [146,108,36,147]. Another difference is unit and its continuation to the Cyclades area. the larger amount of basement rocks in the Menderes massif The Koziakas unit in is composed from the than in the Cycladic massif [65,138,132,145,120,130]. bottom to the top: by pelagic carbonate sediments intercalated Fig9. with radiolarian chert and shales of Middle Triassic-Early Jurassic age, thick-bedded oolithic limestones and redeposited Recent works by [148,30,15,22] support the continuing of the mass–flow sediments of Late Jurassic-Early Cretaceous age Gavrovo carbonate platform, as part of the Apulian`s plate and Early Cretaceous flysch-type sediments equivalent to the passive margin, until the Rhodope metamorphic province, Beotian flysch. Moreover, in the stratigraphic column of the named as the Pangaion metamorphic core complex. It is Koziakas unit are also described shallow water Late Cretaceous exhumed as tectonic window below the metamorphic Serbo- limestones and microbreccia deposits (Thymiana limestones) Macedonian/Rhodope tectonic nappes or terranes of the and finally Paleocene-Eocene flysch, regarding the Koziakas Internal Hellenides. unit as a sedimentary series with a continue sedimentation The Gavrovo zone is thrusted over the Ionian zone towards from the Triassic to the Eocene. Nevertheless, on the Triassic- west during the Olgocene-Miocene. Liassic deep-see sedimentary series of the Koziakas unit overthrust Middle-Late Jurassic ophiolitic mélanges and Pindos Zone the Neotethyan ophiolites arising some questions about the The Pindos zone is characterized by deep-sea sediments existence of the continue sedimentation in the unit, as well (siliceous and other pelagic deposits) of Triassic to late Late as its geotectonic setting [44-45,151-155]. Nevertheless, the Cretaceous age, overlain by a Paleocene-Eocene flysch, Koziakas unit is regarded of many authors as a part of the which shares in places the typical features of a wild flysch. Pindos zone, while form others it has been regarded as an Nevertheless, the Pindos first depositional materials are individual tectonostratigraphic unit of unknown origin thrusted

J Geol Geosci 9 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 8 a and b: P-T-t tectono-metamorphic path and exhumation history of the Paleocene-Eocene high pressure belt (blue schists) in Olympos-Ossa (a) and Cyclades areas (b), respectively (Van der Maar & Jansen 1983, Altherr et al. 1982, Kilias et al 1991, Kilias 1996); c. Field- and microscale photos of the geological units and deformational structures in the Olympos-Ossa (I to V) and Cyclades provinces (VI to VIII). I and II. The Olympos normal detachment zone along which detached SW-wards the Pelagonian nappe pile with the Late Jurassic obducted ophiolites and the overlain Late Jurassic-Cretaceous sedimentary series, resulting to the uplift and final exhumation of the high pressure blue schists and the Olympos carbonate unit (Gavrovo zone). III, IV and V. Meso- and microscale features of deformation of the Olympos high pressure belt. S-C fabrics and shear bands in the blue schists (III and IV) and pyroxene σ-clasts in the intercalated metabasites of the blue schist unit, glaycophan is grown in pressure shadows of the pyroxenes during the high pressure process (V). X-Z sections, main sense of shear top-to-SW during the exhumation processes. VI and VII. Geometry of folds structures in the Cycladic metamorphic belt. They are developed parallel to the stretching lineation related to high temperature metamorphic assemblages, extensional tectonic and crustal uplift. VIII. Megalodonts bearing recrystallized limestones of the Triassic-Jurassic Emporio carbonate unit in island (?Pelagonian nappe, Kilias et al. 1996, Schneider et al. 2018).

J Geol Geosci 10 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 9: Geometry of kinematics of deformation (sense of shear) during the Tertiary extensional tectonics in Hellenides that is progressively migrated towards-SW. Is referred for the ductile deformation (modified after Kilias et al. 2002). during the Paleocene-Eocene on the Pindos unit from the East imbricated with Mid-Late Jurassic ophiolite-mélanges, occur to the West [154,156,28], so that its geotectonic setting, as well in many places on the Triassic-Jurassic Pelagonian carbonate as paleo-geographic position to remain still under discussion. cover or secondary, directly on the pre-Alpine basement. The ophiolites obduction took place during the Mid-Late Internal Hellenides Jurassic, following the intra-oceanic subduction/-s in the Neo- Pelagonian Zone or Nappe Tethyan ocean basin/-s [162-164,24-26,5,58,13,29,17,19]. The Pelagonian nappe or Pelagonian zone is consisted from the The Pelagonian nappe together with the obducted ophiolite top to the bottom of I. a Triassic-Jurassic carbonate platform belt crop out mainly in the continental part of Greece, but also sequence, II. a volcanosedimentary Permo-Triassic series on top of the Cyclades metamorphic complex as small far- characterized by bimodal magmatism and III. a Paleozoic or travelled relics and in Crete island known as the Asterousia older pre-Alpine crystalline basement composed of gneisses, nappe [108,118,149,104,21,72-73]. The basement gneissic amphibolites and schists, intruded by Carboniferous calc- rocks and their Triassic-Jurassic carbonate cover of the Paikon alkaline (~300 Ma) and Triassic A-Type (~240 Ma) granitoides. subzone in the Axios/Vardar zone at Tzena and Paikon Mts Mesozoic or Cenozoic magmatic activity has not been recorded was regarded by [6] as a tectonic window of Pelagonian origin. in the Pelagonian basement [157-161,2,8,5,58]. The Pelagonian Furthermore, clasts of Pelagonian nappe origins are also found nappe was divided by [5,58], due to Alpine tectonic internal in Early Miocene conglomerates deposited above detachments thrusting in a tectonic lower and a tectonic upper Pelagonian faults in the Cyclades province, showing that the Pelagonian segment, both showing the same tectonostratigraphy column, nappe once covered a large part of the Aegean region and finally as it is described just above. Obducted Neo-Tethyan ophiolites, eroded or tectonically denudated [165-167,125]. Nevertheless

J Geol Geosci 11 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis the Pelagonian nappe is also recognized to the North in the The Sub-Pelagonian zone is composed of a sequence of Dinarides while its continuation to the East in Turkey remains Triassic to Jurassic pelagic carbonate and siliceous sediments, until today under discussion [2,36,147,9,5,58]. which lie tectonically over the Mesozoic platform carbonate sediments of the Pelagonian nappe. Today it is traced along Late Jurassic carbonate platform sediments strongly eroded the western Pelagonian margin. Characteristic phase of the and Late Jurassic-Early Cretaceous mass-flows and flysch-like Sub-Pelagonian zone are the red, ammonites’ bearing, pelagic deposits, as well as Late Cretaceous shallow water carbonate sediments of the Hallstatt phase of Late Triassic age. Ophiolites sedimentary series, rest on top of the obducted Neo-Tethyan and ophiolitic mélanges overthrust the Sub-Pelagonian deep- ophiolite realm or directly on the exhumed Pelagonian Triassic- water sediments. The latter emplacement took place during the Jurassic carbonate platform cover [168-174,13,29,19,93]. Late Jurassic, following the general geotectonic history of the Fig10. Alpine orogeny in the Hellenides. A detail path of the complicated, polyphase Alpine tectono- Fig12. metamorphic history of the Pelagonian basement rocks, However, the Sub-Pelagonian zone remains an under debate which is in detail discussed in numerous works by [67-69,5- zone concerning its paleogeographic existence and geotectonic 6,58,8,93,51-53,163,79-80,175,6,176,63] is displayed in. It setting. One scenario wants it to be the Mesozoic continuation shows; I. High-pressure conditions during the Late Jurassic of the western Pelagonian continental margin to the continental associated with thrusting and crustal thickening, II. Amphibolite slope and the deeper basin area towards the Pindos ocean basin to greenschist facies retrogression during the Late Jurassic- [183,2,36,147,17]. The opposing theory of only one, wide, Early Cretaceous and extensional crustal uplift, III. Late Early ocean basin in the east of the Pelagonian nappe (i.e. Meliata- Cretaceous greenschist facies prograde metamorphism related Axios/Vardar ocean basin) explains the position of the Sub- to compression und SW-wards thrusting, IV. Late Cretaceous- Pelagonian zone along the western Pelagonian side as such of Paleocene cooling age of the structurally upper Pelagonian a tectonic nappe nature, having been thrusted, together with parts and mainly brittle deformation during the Paleocene- the ophiolite belt, from the east to the west, on the Pelagonian Eocene characterized with intense SW-wards imbrication and nappe [24-26,163,5,58,13,29,18,22,176,63]. In any case, V. finally from the Oligocene/Miocene to the recent extension the Sub-Pelagonian zone was affected by the Late Jurassic and crustal thinning. In contrast ductile deformation and deformation and the subsequent, younger deformational Fig11. events recognized in the Hellenides orogenic belt, placing the Sub-Pelagonian zone at the Internal Hellenides zones. mylonization under high-pressure conditions which were followed by low-grade retrogression and extension has been In central Greece crops out the Parnassus Triassic-Eocene recorded during the Tertiary for the structurally lower most carbonate unit terminating to an Eocene-Oligocene flysch Pelagonian parts, at their tectonic contact with the underlain and known for the reach bauxites deposits. It is regarded Paleocene-Eocene blue schists belt and the External Hellenides as a platform carbonate sequence possibly belonging to the [51-53,67,68-69,115,68-69]. western more parts of the Pelagonian nappe, although it was not clearly affected by the Jurassic-Cretaceous syn- The Pelagonian basement is regarded either I. as the Mesozoic metamorphic deformation of the Internal Hellenides. On the eastern passive margin of the Apulia continent, with a main contrary, due to the absence of a clear stratigraphic gap in its wide ocean basin in the east, so-called the Neothethyan Meliata/ tectono-stratigraphic column, from the Triassic to the Eocene, Axios/Vardar ocean basin [23,13,29,11,5,58,176,63,177] the Parnassus unit is considered to be a part of the External or II. as a microcontinent emerging in the middle of two Hellenides zones forming a reef coralgal build-up belt, near separate ocean basins that were operating more or less the Pelagonian western margin [184-187,155]. In any case, contemporaneously during the Alpine orogeny; these were the geotectonic-paleogeographic setting of the Parnassus the Pindos ocean in the west and the Axios/Vardar ocean in carbonate sequence remains until today under debate. the east [2,36,147,178-180,37,35,40-41]. As accruing in these The Parnassus unit together with the Pelagonian nappes interpretations, the ophiolite rocks on the two, western and overthrusted to the West the External Hellenides Pindos zone eastern, parts of the Pelagonian nappe should be originated during the Paleocene-Eocene. Its continuation is recognized either from one or two ocean sources, respectively. This leads further to the North in the ``high karst`` zone of the Croatian to an ongoing discussion about the direction of the ophiolites’ and Bosnia and Herzegovina in the Dinarides, where important obduction onto the Pelagonian continent during the Middle bauxites deposits are also appeared, as it is in the Parnassus to Late Jurassic times; either only one main W- to SW-ward unit in Greece [185-188,155]. [181,49-50,182,13,29,11,5,58,18,177,61] or both W- to SW- ward and E- to NE-ward for the ophiolites occurrences at Axios/Vardar Zone the eastern and western Pelagonian margins, respectively The Axios/Vardar zone is structurally another very complicated [2,36,147,178,35]. Hellenides’ zone composed of units of both continental and

J Geol Geosci 12 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 10: Geological-structural map and representative cross-section of the eastern tectonically boundary of the Axios/Vardar zone with the Serbo-Macedonian/Rhodope massif. The Pelagonian nappe is sandwiched between the Europe (Serbo-Macedonian/Rhodope nappes pile) and Apulia (External Hellenides). Based on Tranos et al. (1999), Mainhold et al. (2009), Mainhold and Kostopoulos (2013), Kostaki et al. (2013, 2014), Kilias (2018, 2019). Abbreviations as in Fig. 3.

J Geol Geosci 13 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 11 a and b: P-T-t Alpine tectono-metamorphic path and exhumation history of the Pelagonian and Paikon basements (Paikon subzone of the Axios/ Vardar zone). Red color: granites intrusions in the Pelagonian basement. (Katrivanos et al. 2013, Koroneos et al. 2013, Kilias et al. 2010). c. Meso- and microscale features of the deformational events. I. Main S1 foliation related to isoclinal recumbent folds. Asymmetric F2 folds overprint the previous isoclinal folds. S2 foliation is also shown. Garnet mica schist (Upper Pelagonian segment, Peternik unit). II. Recrystallization of sericite along S2 planes around white mica porphyroclast. Asymmetry of the mica fish indicates top-to-NW sense of shear during D2. XZ section. Garnet-bearing mica gneiss of the Upper Pelagonian segment, Peternik unit. III. Garnet with characteristic zonation and internal fabric (Si) rotated during D2. Chlorite aggregates (after garnet) and sericite growth in asymmetric pressure shadows and along the dominating S2 foliation planes. Garnet σ-clasts and S-C fabric indicate top-to-NW sense of shear. XZ section. Garnet mica schist (Lower Pelagonian segment). IV. S-C fabric in mica gneiss from the tectonic contact between the lower and upper duplicated Pelagonian parts during the Late Jurassic. X-Z section. Sense of shear top-to-WNW. V, VI. Augengneisses of the Pelagonian tectonic sheets in the Axios/Vardar zone (Livadia and Peternik units). Feldspar σ-clasts, S-C fabrics, and shear bands indicate top-to-NE sense of shear (D3 event). XZ section. VII. S1/S2 relationship. S1 is defined by white mica and chloritoid. Chloritoid rotates into S2. YZ section. Garnet-chloritoid mica schist (Lower Pelagonian segment). VIII. Shear bands and S-C fabric indicating top-to-WNW sense of shear during D2. Intensive chloritization of D1 garnet σ-clasts took place during D2. X-Z section. Garnet mica schist (Lower Pelagonian segment). IX. D1 and D2 fold realm on the Triassic-Jurassic carbonate sequence of the Paikon subzone (Gandatch marbles). Isoclinal, recumbent folds related to the D1 event are overprinted by the D2 event. The S2 foliation dominates. X. Calcite σ-clast in the Triassic-Jurassic carbonate sequence of the Paikon basement (Gandatch marbles) indicating top-to-SW sense of movement (D1). XI. S1/S2 fabric in the Late Jurassic volcanosedimentary formation of the Paikon subzone (Kastaneri formation). The old Upper Jurassic S1-foliation is strongly reoriented along the S2 foliation, forming a granulation cleavage fabric. Due to the strong translation along the S2-planes, the two foliation are usually developed parallel to one another, so that only one fabric element seems to be recognized, on the formation and this is the S2-foliation. Paikon subzone, Axios/Vardar zone. XII. Brittle D4 thrust zone towards SW cutting the main S2 foliation. Brittle also, D5 semi-low angle normal fault zone cutting the D4 thrust zone and S2 foliation with a top- to-NE sense of shear. Late Jurassic volcanosedimentary formation of the Paikon subzone (Kastaneri formation). XIII, XIV. B-axis scattering of D2-isoclinal folds due to their re-orientation subparallel to the X-axis of the strain ellipsoid. X-axis SW trending. Triassic-Jurassic carbonate sequence of the Paikon basement (Gandatch marbles). XV. Kink-folds in the Late Jurassic-Early Cretaeous carbonate Griva formation of the Paikon subzone related to the Paleocene-Eocene compressional event (D4). Microscopic pictures: III, IV, VII, VIII with one nicol, II, VI with crossed nicols. (modified after Kilias et al. 2010, Katrivanos et al. 2013).

J Geol Geosci 14 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 12: Field photographs of the ?Sub-Pelagonian zone at the western margin of the Pelagonian nappe (modified after Kilias et al. 2016). I. Green-schists and deep-water sediments of the Sub-Pelagonian zone with conjugate set of tension gashes related to a vertical maximum σ1-axis and a subhorizontal σ3-axis. A dynamics that coincides with the Oligocene-Miocene extension (D5 event) and the carbonate Olympos- Ossa unit exhumation under the downwards detached blue schists unit and the Pelagonian nappe pile. II, III, IV, V. Multicolored deep-water sediments composed by green-schists, red and green colored radiolarian cherts, pelagic red carbonates and metapelite rocks, possibly of Jurassic age. They show low grade metamorphism but they are intensively deformed by compressional structures (e.g. isoclinal folds, reverse shear bands, and brittle thrust faults), as well as extensional structures (e.g. down-dip shear bands, S-C fabric and semiductile normal fault zones). These deep-sea sediments were together with the ophiolite belt overthrust the neritic Triassic-Jurassic carbonate rocks of the Pelagonian nappe during the Late Jurassic. The sense of movement during their initial emplacement is not clear here due to the intensive after emplacement multi-phase deformation, affected progressively these rocks. VI. Red carbonates sediments, lying under the previous multicolored metasediments. They represent a deep-sea basin environment and show a sedimentary brecciation, as well as a turbidity layering. Their contact with the underlying Paleozoic Pelagonian schists and Triassic-Jurassic Pelagonian platform carbonate cover is a Neogene-Quaternary normal fault zone. The age of this sequence remains under debate. It should most likely be of Jurassic age equivalent to the previously ones described multicolored deep-water sediments of the ?Sub-Pelagonian zone, having been also overthrusted the neritic Triassic-Jurassic Pelagonian platform carbonate cover during the Late Jurassic together with the Neotethyan ophiolites. oceanic origin. Traditionally, it is subdivided in three (3) In a general view, the Axios/Vardar zone forms the suture subzones. They from the west to the east, are: the , zone between the Apulia/Pelagonian and European continents, the Paikon and the subzones [168,49-50]. Low–grade although its exact initial geotectonic position remains still to un-metamorphic ophiolites and Mid-Late Jurassic ophiolitic under debate. Several different interpretations have been mélanges are intensively imbricated with the Paleozoic proposed about the geotectonic position and structural continental basement rocks and Mesozoic sedimentary series, evolution of the Axios/Vardar zone. Some authors regard that as well as Late Jurassic arc-type calc-alkaline granitoids, existed two ocean basins in the present-day Axios/Vardar zone which crosscut also in places both the basement slivers and the separated by the Paikon volcanic arc. Western of the Paikon ophiolites (e.g. the Fanos granite), [189-190,5,58,61]. arc there was the Almopia ocean basin with Triassic while eastern of the Paikon arc evolved in a back-arc Fig. 13.

J Geol Geosci 15 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis region the Paionia ocean basin during the Mid-Late Jurassic, sediments covered the Paionia oceanic crust. Furthermore, the simultaneously with the subduction of the Almopia ocean same Mid-Late Jurassic age for the Paionia oceanic crust is beneath the Paikon continental arc [191,74,147,179-180,14,20- also concluded by [192] determining an isotopic age of 166Ma 21]. The Mid-Late Jurassic age of the Paionia oceanic crust is for a plagiogranite from the Paionia ophiolites. Similar Middle also documented by [36] using radiolarian ages of deep-sea Jurassic ages (Bajosian) of radiolarian assemblages in the

Figure 13: Geological-structural map and representative cross-section of the whole Axios/Vardar zone (including the Almopia, Paikon and Paionia subzones) and its contact with the eastern Pelagonian margin at Voras and Paikon/Tzena Mts. The Paikon basement and its Triassic- Jurassic carbonate cover are shown as a tectonic window of Pelagonian origin beneath the obducted Neotethyan Axios/Vardar ophiolites and the Late Jurassic island arc type magmatic products (Volcanosedimentary series, VS). The Late Jurassic-Early Cretaeous and Late Cretaceous sedimentary sequences are also shown. (based on Mountrakis 1986, Mercier 1968, Galeos et al. 1994, Brown and Robertson, 2003, 2004, Katrivanos et al. 2013, 2016, Kilias et al. 2010). Abbreviations as in Fig. 3.

J Geol Geosci 16 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis cherts, stratigraphicaly on the top of the Vourinos ophiolites Cycladic Massif at the western edge of the Pelagonian nappe, have been also Following the traditional subdivision of the Hellenides recorded by [193]. in isopic zones we describe here individually the In another view the Paionia ocean basin formed during the tectonpstratigraphic profile of the Cycladic massif, although Mid-Late Jurassic in a supra-subduction zone setting (Meliata- its compositional units have been already described separately Axios/Vardar ocean realm, [11,22] or back-arc region, behind in the corresponding zones, where these units belong. The of an ensimatic island arc, resulted by a Middle Jurassic intra- Cycladic massif is composed by a complicated, heterogeneous oceanic subduction in the Neotethyan Meliata-Axios/Vardar nappes stack system including parts of the Internal, as well ocean basin [162,194,192,11,18,61]. In this case, the Paikon as External Hellenides zones. In a general view the Cycladic subzone represents a tectonic window of the Pelagonian nappe tectonostratigraphy can be given as follows, although it can origin, where both the ophiolites of the Almopia’s and Paionia’s not be mapped entire in a region due to evolution of individual subzones together with the ensimatic arc volcanosedimentary only parts of the whole Cycladic massif section in the small products initially were SW-ward obducted during the Late islands of the central Aegean see (Cyclades islands), the Attica Jurassic (Kimmeridgian/Tithonian) from a single ocean basin, peninsula and the south Evia island [118-119,108,65,120- the Axios/Vardar basin, eastern of the Pelagonian continental 125,128-129,140-141,206]: The deepest unit comprises a margin [162,4-5,58,13,29,62,6,61]. On the contrary, others Variscan or older basement of schists and gneisses, as well as authors assume also an about simultaneously Late Jurassic- Carboniferous granitoids (~300Ma) and abundant Oligocene- Early Cretaceous E- to NE-ward emplacement of the ophiolites Miocene migmatites and granites. It constitute the most deeply on the Pelagonian nappe from an ocean, the Pindos ocean exhumed parts of the Hellenides belonging to the Apulian basin, western of the Pelagonian [2,37,40-41] or even more basement of the External Hellenides, possibly equivalent to the others regard only one E-ward ophiolites emplacement on the Menderes Massif, as it is discussed previous [128-129,206,9]. from the Pindos ocean e.g. [35]. The Cycladic basement is overlain by a post-Variscan, Alpine sedimentary cover, containing marbles, metapelites and Early On the other hand, Axios/Vardar ophiolites of the eastern Triassic volcanic intercalations which forms the metamorphic more part of the Axios/Vardar ocean basin were obducted continuation of the Apulian passive-margin`s, Gavrovo during the Late Jurassic on the European margin but with a carbonate platform sequenece. The marbles contain emery and NE-wards sense of movement [33,195-197,22,55]. In this metabauxites in some places, e.g. in the island [9,206- case, the simultaneous during the Late Jurassic SW-ward and 207]. Tectonically on the Alpine passive-margin sequence NE-ward ophiolites obduction on both continental margins rests the Paleocene-Eocene high-pressure belt of marbles, of the Pelagonia and Europe, was resulted by an arcuate metapelites and metabasites intercalations, as in the Olympos- type northwestward-convex intra-oceanic subduction of the Ossa and Pelion areas, here in Cyclades with eglogites also western more part of the Meliata-Axios/Vardar ocean realm or occurences. Highly attenuated ophiolitic mélanges containing the Meliata-Maliac ocean [30,15,22]. slivers of oceanic crust formed during ~80-70 Ma [208-209] Fig14. are also incorporated in this Paleocene-Eocene high-pressure A more recent scenario sees the whole Axios/Vardar zone as belt which is considered as the subducted parts of the Pindos allochthonous, originated further to the East and emplaced zone beneath the Pelagonian nappe [140-141,30,15,22]. secondary as a tectonic nappe in its present position and the All lithologies from the basement to the post-Variscan Axios/Vardar suture zone is located at deep along the NE sedimentary cover show this Paleocene-Eocene high-pressure boundary of the Rhodopes, which builds up the most eastern metamorphic overprint [65-66,70,121]. Additionaly, an nappes pile of the Internal Hellenides rooted along this suture intensive Oligocene-Miocene high-temperature/low pressure zone e.g. [30,15,22,28,150,198]. retrogressive metamorphism until migmatisation is observed Continent collision of Apulia and Europe, followed the finale elsewhere [117-118,125]. The P-T-t tectonometamorphic path closure and suturing of the Axios/Vardar ocean basin, occurred of the Cycladic massif is given in detail. in the Paleogene (Paleocene-Eocene) after subduction On the Cycladic high-pressure belt was emplaced during the during the Late Cretaceous of the remnants of the Axios/ Eocene-Oligocene the Pelagonian nappe with the Jurassic Vardar ocean realm beneath the European continental margin obducted Neotethyan ophiolites of the Axios/Vardar ocean [36,147,19,17,30,15,22,43]. A Late Cretaceous calc-alkaline but today, due to the intensive Ologocene-Miocene extension magmatic arc in the Sredna-Gora province clearly notes the they were totally tectonically denudated and eroded and only Late Cretaceous subduction of the Axios/Vardar ocean [199- as small rests are saved or as conglomerates clasts in the 203]. This Axios/Vardar suture zone is continued further to the sediments of the Neogene basins [118,108,165]. North, called Sava zone and to the East to the Ankara suture Today the Cycladic high-pressure belt constitutes a typical zone in Turkey [36,147,19,204-205,11,83,22]. metamorphic core complex exhumed during the Oligocene- Fig15. Miocene extension in Hellenides along normal detachment

J Geol Geosci 17 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 14: Geological-structural map and the corresponding representative cross-section of the eastern Axios/Vardar zone (Paionia subzone) and the Circum-Rhodope belt which is regarded as the sedimentary sequence initially deposited on the western margin of the Serbo-Macedonian massif (European margin). The ensimatic island arc related intrusion of the Fanos granite is shown, overthrusted together with the ophiolites on the eastern Pelagonian margin. The tectonic contact between Europe (Serbo-Macedonian) and Apulia (Pelagonian) is also shown. (based on Mainhold et al. 2009, Mainhold and Kostopoulos 2013, Tranos et al. 1999, Michail et al. 2016, Kilias 2018, 2019). Abbreviations as in Fig. 3.

J Geol Geosci 18 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 15: Geological-structural map and representative cross-section of the Vourinos ophiolites and the western Pelagonian margin, including the Zygosti stream ophiolite rocks and the Late Jurassic-Early Cretaceous and Late Cretaceous carbonate series overlain unconformably either the Vourinos ophiolites or the Zygosti stream ophiolite rocks, western and eastern of the Pelagonian Triassic-Jurassic carbonate cover, respectively (based on Mountrakis et al. 1993, Carras et al. 2004, Brunn 1956, Rassios and Dilek 2009, Photiades et al. 2007). Abbreviations as in Fig. 3.

J Geol Geosci 19 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis faults associated with mylonites formation and high- Pangaion Unit temperature metamorphism in the deeper tectonic levels The structurally lower most Rhodope Pangaion unit consists [119,9-10,142,121-122,125]. Nevertheless a number of studies of mica-schists, gneisses and marbles intercalations, covered argue that extension started no earlier as the Early Miocene in the higher levels by a thick marble sequence. The age of [210,120,140-141,206,124]. the unit is under debate. In recent works, it is appointed as Serbo-Macedonian/Rhodope Metamorphic Province a segment of Variscan or older continental crust covered by (SRB/RHD) a thick marble sequence, of possible Mesozoic age [211- 212,218-219,20-21,30,15,22]. Nevertheless, other authors In this work, we regard the Serbo-Macedonian massif as suggest a Paleozoic age for the whole Pangaion unit, including one with the Rhodope metamorphic province [3,30,15,22]. the overlain thick marble sequence [220-224]. The pre-Alpine In this case, the Serbo-Macedonian/Rhodope metamorphic and Mesozoic sequences of the Pangaion unit were intruded by province is bordered to the west by the Axios/Vardar zone Oligocene-Miocene granitoids and during the Alpine orogeny and the Circum-Rhodope belt, while its other boundary to the underwent low grade metamorphism under greenschist facies Northeast constitutes the Maritsa dextral strike-slip fault in conditions [211-212,225,148]. Boulgaria. Fig16. The SRB/RHD occupies the easternmost part of the Hellenides. It is consisted of a complicated Alpine nappe stack of several The Pangaion unit is variably interpreted until today as metamorphic units or terranes of both continental and oceanic a metamorphic core complex belonging to the External origin with the Rhodopes constituting the core of the arc-type Hellenides Apulia plate [148,30,15,22,28,150,198] or a Hellenic orogenic belt. The SRB/RHD is traced with the same mikrcontinent, named or Thracia terrane, [3,219] accreted to the European continent, either during the Early- structural architecture further to the North, in and Middle Jurassic following the closure of a Triassic age`s ocean Serbia and possibly to the East in NW Turkey [9,12]. basin [20-2] or during the Cretaceous [213,219,16]. The several SRB/RHD nappes were progressively emplaced The Pangaion unit is bordered to the Northeast by the Nestos one over another by intense Jurassic to Tertiary compressional shear zone. It is interpreted as a ductile thrust zone along which tectonics and thrusting, in the peculiar position between the the tectonically middle Rhodope Sidironero unit overthrusted Apulia plate in the west and the European plate in the east, the Pangaion unit during the Tertiary [15,22, 30], although where the Meliata-Axios/Vardar ocean basin was evolved some others authors dated the Nestos thrust zone as of e.g. [211-215,3,6-8,93,54,30,15-16,22,176,63]. Nappes’ Cretaceous or Jurassic age e.g. [213,20-21,16]. Furthermore, stacking took place during alternating periods of continental [219] are interpreted the Nestos thrust zone as a suture zone crust segments collision and oceanic lithosphere subduction. between the lower Rhodope Pagaion unit and the middle Subsequently, extensional tectonics associated with normal Rhodope Sidironero unit of Jurassic-Cretaceous age. detachment faults and ductile to brittle tectonics from the Paleocene to Early Miocene, led progressively to orogen On the contrary, the southwestern border of the Pangaion unit collapse and exhumation of deep crustal levels. This Tertiary is controlled by an Oligocene-Miocene normal detachment zone along which the Serbo-Macedonian massif was detached extensional period was accompanied with syn- to post-tectonic SW-wards, resulted to the finally exhumation of the Pangaion granitoids’ intrusions and abundant migmatites formations metamorphic core complex and the formation of the supra- [148,214-217,54]. detachment Neogene Strymon basin [211-212,226-227,148]. The orogen collapse and tectonic nappes denudation were Sidironero and Kimi Units related to a main top-to-the-SW sense of movement, at least for the Greek part of the SRB/RHD. On the other hand, the The tectonically overlying the Pangaion metamorphic core dominant thrusting direction is also detected as W- to SW- comlex middle Rhodope Sidironero and upper Rhodope Kimi ward [211-213,16], although in the field observations the units are very heterogeneous. They both units are composed direction of shearing related to compression is fairly difficult by oceanic and continental origin`s rocks. We distinguish here, to be distinguished from the direction of shearing related to mafic and ultramafic metaophiolites, amphibolites, ortho- and the subsequent extension and collapse, so that the issue still paragneisses and marbles of Paleozoic or older age, as well as remains under debate [211-212,148,214-215,6-8,93,54,16,22]. of possible Mesozoic age marbles strata and metaophiolites. Paleocene to Oligocene adakitic and calc-alkaline granitoids In the Greek part, the SRB/RHD nappes pile, from the related to the Tertiary Rhodope extensional regime, intrude tectonically lowermost to the tectonically higher nappes, is the basement rocks of these two Rhodope units [216,148,228- composed by the Pangaion, Sidironero and Kimi units in the 232,24,202,22]. Additionally, [219] dated also Late Jurassic- Rhodope province and by the Kerdylia and Vertiskos units in Early Cretaceous arc-type granitoids intrusions into the the Serbo-Macedonian province, respectively. Sidironero unit, interpreting the Sidironero unit as a Late

J Geol Geosci 20 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 16: Geological-structural map and representative cross-section of the Pangaion metamorphic core complex and the Serbo-Macedonian/ Rhodope nappes pile. The Paleocene-Eocene Nestos thrust zone (Jahn-Awe et al. 2010, Froitzheim et al. 2014) and the Oligocene-Miocene Strymon valley normal detachment fault zone (Dinter 1998, Dinter and Royden 1993), as well as the Miocene- supra-detachment Strymon basin are shown (Kilias et al.2013, 2016). Abbreviations as in Fig. 3.

Jurassic subduction related volcanic arc, and the Pangaion unit if we take also in to account the structural level of the Kesebir- as a microcontinent unterthrusted the Sidironero unit during Kardamos and Kechros domes, exactly below the Kimi unit, the Late Cretaceous, although this interpretation remains their geotectonic-paleogeographic position equivalent to the under discussion e.g. [223-224,30,15,22,28,150,198]. Pangaion unit is under dispute. Taking in to account all these differences of the Kesebir-Kardamos and Kechros domes to In the Greek mainly Rhodope province, two dome-shape the Pangaion unit, these two metamorphic domes should be tectonic windows, the Kesebir-Kardamos and Kechros domes, regarded as two tectonic windows equivalent to the Sidironero exhumed along Tertiary normal detachment faults below the unit [6-8,93-94,59,61]. upper Rhodope Kimi unit and composed by Paleozoic gneissic and schists rocks intruded by Variscan and Triassic, as well as Ultrahigh- and high-pressure eclogite facies metamorphic Tertiary granitoids, have been grouped together with the lower paragenesis remnants, as well as ultrahigh-pressure diamond- most Pangaion metamorphic core complex [54,219,30,15-16]. bearing rocks were described for both the Sidironero and Nevertheless, these Kesebir-Kardamos and Kechros domes, Kimi units, mainly preserved within basic Morb-type bodies, do not characterized by the thick carbonate cover sequence tectonically incorporated into high-temperature gneisses and dominated in the Pangaion unit and they were affected by a amphibolites [238,78-80,11]. High-pressure conditions were higher grade Tertiary metamosphism than the Pangaion unit related to subduction and compression, as well as nappe associated also with migmatization that is not observed in the stacking. However, the ages of the ultrahigh- and high- Pangaion unit [211-212,233-235,54]. Furthermore, they were pressure parageneses are not yet clear. The ultrahigh-pressure exhumed during the Eocene-Oligocene (42-30Ma), as it is metamorphism with the diamond bearing parageneses has been shown by their cooling age that is the same with the Sidironero dated as possible of Early Jurassic age [79-80,82-85,42]. It unit [236]. Cooling age of the Pangaion unit dated at the has been evolutionary, possibly related with the closure of the Oligocene-Miocene (26-10Ma) [236-237]. According to that, Paleotethys around 200 Ma ago (in the Early Jurassic) and thus

J Geol Geosci 21 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis represents the palaeogeographic location of the actual suture most Rhodope Pangaion unit [211-212,225-226,148]. of the Paleotethyan ocean [103,85,22]. Early Cretaceous ages At the boundary between the Vertiskos and Kerdylia units for high-to ultrahigh-pressure metamorphic event have been crop out tectonically metamorphic mafic and ultramafic rocks also appointed by [77,239,81]. of oceanic lithosphere origin, named as the ophiolite Furthermore, high-pressure metamorphism and eclogites complex [244-245]. Recently works dated as Late Jurassic formation, recorded within both Kimi and Sidironero units, age`s the protolith of the Volvi ophiolite complex and this have been dated between the Paleocene and Eocene by using is originated in the Axios/Vardar ocean basin, emplaced in the U-Pb SHRIMP method on zircon [78,81] or the Lu-Hf its today position during the Paleocene following the finale method on whole rock and garnet fractions [86]. Recently, Axios/Vardar ocean closure [30,15,22]. Nevertheless, [20-21], isotopic data of high-pressure suggest an Early Jurassic emplacement of the Volvi ophiolite complex sandwiched between the upper Vertiskos and the Fig17. lower Kerdylia unit and originated in a Volvi-East Rhodope rocks from the Byala Reka–Kechros Dome (Kazak eclogites) ocean basin. In this scenario the Kerdylia unit is considered in the Eastern Rhodopes of Bulgaria indicated, that eclogite- equivalent to the lower most Pangaion Rhodope unit. Here, facies metamorphism occurred during the Late Cretaceous arises a question because the Volvi ophiolite complex protolith (81.6 ± 3.5 Ma; [42-43]. It is in a very well concordance with has been dated as Late Jurassic age`s. Furthermore, [218,246] the proposed Late Cretaceous subduction of the remnants interpret this tectonic contact between Kerdylia and Vertiskos of the Neotethyan Axios/Vardar Ocean below the European units as a secondary reactivated normal detachment fault zone margin and the formation of the Late Cretaceous magmatic of Eocene-Oligocene age along which the overlain Vertiskos arc in the Sredna-Gora massif [199-203]. We follow the Late unit detached westwards causing the exhumation of the lower Cretaceous age of the high-pressure metamorphism because it Serbo-Macedonian Kerdylia unit. is more compatible with all the post high-pressure`s structural According to the most resent works the Kerdylia unit is evolutionary stages of the Rhodope nappe stack and their regarded as an equivalent to the Rhodope Sidironero unit exhumation processes, as well as the modern geotectonic which tectonically lies along the Nestos thrust zone on top of setting of the overall SRB/RHD metamorphic province [236- the eastern side of the Pangaion unit. It is concluded by its 237,30,15,22,42-43,28,150,198]. same to the Sidironero unit, Eocene-Oligocene cooling age, High-pressure metamorphic event, compression and nappe structural setting and tectonostratigraphy, therefore belonging stacking was progressively followed by a Paleocene to Eocene to the proposed SRB/RHD metamorphic nappe stack retrogressive high-temperature in the amphibolite facies [225,148,236,30,15-16,22]. Moreover, dating of granitoids metamorphism, partly reaching migmatization conditions and and migmatites of the Kerdylia unit reveal ages of Late Jurassic it was identified again in both the Sidironero and Kimi units. and also of Permo-Carboniferous [242-243], again the same as High- grade temperature metamorphism is related to extension it is recorded for the Sidironero unit [247]. and collapse of the Rhodope nappe stack, resulting in the Vertiskos Unit gradual exhumation of the Rhodope units. From the top to the bottom; initially, the Kimi unit was exhumed in the Paleocene- The Vertiskos unit mainly comprises, amphibolites, schists, Eocene, followed by the Sidironero unit’s exhumation in the ortho- and paragneisses and in places thin marbles layers of a Eocene-Oligocene, and finally that of the Pangaion unit in the Paleozoic age protolith [248-249,243]. Furthermore, abundant Oligocene-Miocene [211-212,216-217,225,148,54,30,15,6- migmatite rocks also occur in the lithostratigrapic composition 8,93-94,22]. of the Vertiskos unit. Nevertheless, their age remains under Kerdylia Unit debate ranging from the Paleozoic to the Tertiary [241,250- 251]. A-type leucocratic granitoids (e.g. Arnea granite) of As mentioned earlier, the Serbo-Macedonian massif is divided Early Triassic age (~240-220Ma) intrusions in the Paleozoic into the lower Kerdylia unit and the higher Vertiskos unit. The rock sequence have been formed during the continental rifting Kerdylia unit is consisted of Paleozoic gneisses and schists, of the Pangaea supercontinent [243,249,161,8]. Moreover, as well as a thin marble cover of unknown age, constituting Neotethyan ophiolite bodies are also met, secondary, the highest lithostratigraphic sequence of the unit. Migmatites tectonically intercalated in between the Vertiskos basement are also occurred with their age until today under discussion, gneissic and schist rocks [241,3,56-57]. The ophiolites were ranging possibly from Paleozoic to Tertiary. [240,95,181,241- initially obducted NE-wards during the Late Jurassic on the 243] [20-21] recognizes the marble cover as a possible Triassic Serbo-Macedonian Vertiskos unit, which formed the European continental sedimentary series. The Kerdylia unit is tectonically continental margin at the eastern part of the Neotethyan Axios/ placed on top of the western side of the Rhodope Pangaion Vardar ocean basin [195,30,15,22,56-57]. unit along the Oligocene-Miocene normal detachment fault zone, previous described as the western structural boundary of In the Vertiskos unit, similar as in the Rhodope Sidironero the Rhodopes and causing the finally exhumation of the lower and Kimi units, high-pressure to ultra-high-pressure diamond-

J Geol Geosci 22 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 17 a and b: P-T-t Alpine tectono-metamorphic path and exhumation history of the (a) Rhodope Pangaion and Sidironero units and (b) Serbo- Macedonian Vertiskos unit (Papadopoulos and Kilias 1985, Kilias et al. 1999, Kilias and Mountrakis 1990, Froitzcheim et al. 2014, Miladinova et al. 2018, Wuethrich 2009, Liati and Gebauer 1999). c. Meso- and microscale compositional features and architecture of the deformational events within Rhodope and Serbo-Macedonian massifs. Shear sense criteria along X-Z sections (Kilias et al. 1999, 2016). I, II. Fossiliferous Triassic-Jurassic carbonate cover of the Serbo-Macedonian continental margin (European margin). Gastropods (I) and ammonites (II) fossils are distinguished. III. Isoclinal recumbent fold of the Upper-Jurassic-Lower Cretaceous sedimentary series on the top of the Late Jurassic obducted ophiolites at the western European margin (Serbo-Macedonian massif). The isoclinal folds and the, fold axial plane parallel, S2-foliation belong to the late Early Cretaceous age`s D2-event. Axios/Vardar zone, Paionia Subzone. IV, V. Asymmetric boudins and σ-clasts of leucosoms in Paleocene-Eocene migmatites of the Sidironero unit (Rhodope massif). A top-to-the-SW sense of movement is clearly recognized. VI. S-C-C` fabric of Paleocene-Eocene age in orthogneisses (?Carboniferous age`s) of the Rhodope Sidironero unit. Sense of shear top-to-the-SW. VII. Sheath-folds, re-oriented parallel to the dominant SW-NE trending stretching lineation (X-axis of the strain ellipsoid) in the Pangaion unit`s marbles. VIII. σ- and δ-type feldspars clasts within augen gneiss of the Serbo-Macedonian Vertiskos unit at Kerkini Mt. The sense of shear is top-to-East (D2 event). IX. Pervasive shear bands and asymmetric quartzitic boudins within schisto-gneissic rocks of the Serbo-Macedonian Kerdylia unit. The sense of shear is top-to-NE. X, XI, XII. Shear bands, σ-feldspars clasts and mica “fish” from mica-gneisses of the Serbo-Macedonian Vertiskos unit. Sense of shear clearly top-to-ENE/NE, related to the Paleocene-Eocene D4 event and the exhumation of the Vertiskos unit. The mica note the S2 foliation strongly re-oriented during the D4 shear bands formation. Microscopic pictures: X, XI, XII with one nicol (detailed description of the deformational events in chapter “Architecture of deformation and structural evolution”).

J Geol Geosci 23 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis bearing parageneses have been recorded [250-251]. Their age event during the Paleogene the initial Late Jurassic NE-wards once more remains under debate. It ranges from Paleozoic stacking direction was reversed to SW-wards thrusting causing to Mesozoic e.g. [250-252]. Moreover, amphibolite facies intense imbrication of the CRB unit and the final emplacement metamorphic conditions of Late Jurassic-Early Cretaceous of the Vertiskos Unit on the CRB along a NW-SE stricking followed by green schist facies Late Cretaceous syn- dextral transpression fault zone [214-215,5-8,58,93,258]. metamorphic, ductile shearing have been recognized for Architecture of Deformation, Magmatic and Depositions the metamorphic rocks of the Vertiskos unit [245,214-215]. Processes Remnants of a Variscan age metamorphism are also recorded [241,253-254,249,243,255]. The cooling age of the Vertiskos Based on our detailed studies for the Hellenides deformational unit has been dated as of Late Cretaceous-Paleocene age history and structural evolution, as well as all the recent [236,256]. works from others authors concerning the geological aspects of the Hellenides (i.e. [9,54,30,15,17-19,22,176,63,261], we Structurally, the Vertiskos unit occupies the same tectonic describe in the following the main architecture of deformation level with the Rhodope Kimi unit and shares a same and kinematics, as well as the structural evolution of the lithostratigraphic composition. Additionally, as analytically Hellenides during the Alpine orogeny, giving additionally, our described above, it records a similar cooling age and tectono- one new or opposite views to the already published works. metamorphic evolution to the Kimi unit [217,236]. Therefore, both units could be regarded as parts of the same tectonic For the better understanding and explanation of the Alpine nappe belonging to the SRB/RHD nappes pile system, above structural-geodynamic evolution of the Hellenides, we consider the Sidironero/Kerdylia nappe system [218,236,6-8,93,22]. important, before the analysis of their structural architecture Nevertheless, the somewhat older Late Cretaceous-Paleocene to provide here a brief summary, first (I) of the magmatic cooling age of the Vertiskos unit show that it was at least one activity affected the Hellenides from the Upper Paleozoic to level higher than the Kimi unit or a possibly higher tectonic the Neogene-Quaternary and second (2) of the syn- and post nappe [16]. ophiolites obduction, Late Jurassic to Late Cretaceous/Early Tertiary sedimentary processes recorded in Hellenides. They The Vertiskos unit is bordered to the West by the Axios/Vardar are very important for the dating of the several deformational zone, as it is earlier in detail described and the Circum-Rhodope belt (CRB). The latter is an Alpine volcanosedimentary events affected the Hellenides. sequence, composed of Triassic-Jurassic pelagic and neritic Hercynian to Neogene Magmatism sediments, distal and proximal of the continental margin. Initially, an Upper Paleozoic magmatism (~300 Ma) related They include platform carbonate sequences, shales and to calc-alkaline granitoids’ intrusions within the Paleozoic flysch-type rocks, tectonically intercalated with Triassic basement units of the Internal Hellenides, related with bimodal-type volcnanic products and acid-to-intermediate subduction processes and the Paleotethys closure, has been island arc ensimatic volcanics rocks formed in a Mid-Late widely described by several authors [2,262-263,160,8,189- Jurassic intra-oceanic subduction zone. Moreover, a NW-SE stricking tectonic slice of pre-Alpine gneisses and schists 190]. A-type granitoids and bimodal-type volcanic rocks belonging to the Serbo-Macedonian Vertiskos unit, the so of Early Triassic age (240 Ma) that have also intruded the colled Stip-Axios massif, is also tectonically incorporated Paleozoic basement units of the Internal Hellenides, have inbetween the Mesozoic-Alpine geological formations od been interpreted as a magmatism related to the initial Permo- the CRB [240,95,257,162,258-259]. Equivalent units to the Triassic continental rifting of the Pangaea and the Neotethys Circum-Rhodope belt are the -Maronia unit ocean opening [161,8]. Mid-Late Jurassic arc-related volcanic in northeastern Greece, as well as the allochthonous Strandja products and magmatic activity with granitoids intrusions and Mandrica units in Bulgaria [30,15,22]. The CRB shows have been recorded in the Axios/Vardar zone and the Serbo- a blueschist facies metamorphism of probable Jurassic age, Macedonian/Rhodope metamorphic province, intruding overprinted by a greenschist facies metamorphic event during the ophiolites and the continental basement rocks during the Cretaceous. [260,251,257-259,240,95] interpreted the the Axios/Vardar intra-oceanic subduction processes and CRB as the Alpine, Triassic-Jurassic sedimentary cover of the their progressive stages, including the ophiolites obduction continental margin of the Vertiskos unit (western European [162,189-190,264,6,22,55,61]. Late Cretaceous calc-alkaline margin) towards the Axios/Vardar ocean basin. According arc-type magmatic activity is described for the European to more recent works [33,195,30,15,22] the CRB and its margin in the Sredna-Gora/Strandja massif due to the NE- equivalent units were initially tectonically placed over the wards subduction of the remnants of the Axios/Vardar oceanic Vertiskos margin together with the Neotethyan Axio/Vardar lithosphere under the Europe. ophiolites with a main NE-ward emplacement direction during Fig18. the Late Jurassic in the course of an arc-continent type collision and forming the uppermost tectonic nappe of the Serbo- This Late Cretaceous magmatic activity migrated to the Macedonian/Rhodope nappes’ pile. Through younger tectonic Southwest, as it shown by the granite intrusions ages arrived

J Geol Geosci 24 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis from 80Ma till 70Ma to the SW along the European margin. development. From the older formation to the younger one, This proximity could be interpreted by a SW-wards rollback of they are: I. The Mid-Late Jurassic ophiolitic mélanges, II. the subduction zone [265-267,227,190,43]. The Late Jurassic to late Early Cretaceous neritic carbonates and mix-deposits and III. The Late Cretaceous shallow-water Additionally, Paleocene to Miocene magmatic activity and carbonates and Paleocene flysch. The first (I) formation was Tertiary migmatization have been mainly recognized in the deposited during the Mid-Late Jurassic overthrusting and Serbo-Macedonian/Rhodope and Cyclades metamorphic emplacement of the Neotethyan Axios/Vardar ophiolites on provinces, related to subduction or mantel delamination the Pelagonian and Serbo-Macedonian continental margins processes associated with normal detachment faulting respectively, while the second (ΙI) and third (ΙΙΙ) groups were linked by extension e.g. [119,216,202,232,230,268,30,15,6- deposited after the Late Jurassic ophiolites obduction on these 8,93,125]. Finally, Neogene and Quaternary volcanic products both continental margins. are recorded in the broader Axios/Vardar zone and the active Hellenic volcanic arc [269-274]. Fig20 Fig19. The Mid-Late Jurassic Ophiolitic Mélanges Jurassic to Late Cretaceous-Paleocene Sedimentation This formation constitutes an intensively imbricated ophiloitic Processes mélange succession of Mid-Late Jurassic age reaching in places until several hundred meters thickness [275-276,18- Here could be distinguished three main lithostratigraphic 19]. It is characterized as a “block-in-matrix” complex with formations for the sedimentation processes from the Middle- a complicated compositional structure, composed by up to Late Jurassic to the Late Cretaceous-Paleocene. We consider kilometer-sized exotic blocks (Olistholiths) of pelagic and their composition and stratigraphic age very important for shallow water carbonates sediments Triassic-Jurassic age`s, the dating and discrimination of the structural events affected radiolarites, basaltes, serpentinites, pillowed and massive the Hellenides and the interpretation of their geotectonic lavas and gabbroic rocks, as well as amphibolites from the

Figure 18: Schematic crustal scale transects showing the geotectonic setting of the Hercynian granitoids intrusions (~300Ma) into the Pelagonian continental margin and the Permo-Triassic magmatic activity (240 Ma: A-type granitoids intrusions and bimodal volcanes) during the initial stages of the Neotethys opening (modified after Koroneos et al. 2013). Sedimentation processes from the Early Triassic to Late Jurassic take place at both Pelagonian (Apulia) and Serbo-Macedonian (Europe) passive continental margins. Sedimentation was broken down by the Late Jurassic Neotethyan ophiolites obduction (Kilias et al. 1999, 2010, Jahn-Awe et al. 2010, Katrivanos et al. 2013, Froitzheim et al. 2014).

J Geol Geosci 25 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 19: The Tertiary until today SW-wards migration of the dynamic peer compression vs extension, responsible for the configuration of the Hellenic orogen and its structural architecture is illustrated (HP=high pressure). The associated Tertiary P-T metamorphic paths of the several high-pressure belts in several regions of the Hellenides are also shown (modified after Kilias et al. 1999, 2002). amphibolitic metamorphic sole, interbedded in radiolarites, the top and on the other hand between the Pelagonian or Serbo- radiolarian cherts, shales and siliceous shales, which dated Macedonian Triassic-Jurassic carbonate platform cover at the Bathonian to Oxfordian age`s from radiolarian assemblages. bottom and the ophiolites at the top. The internal deformation Furthermore, redeposited fine-grained carbonates and of the mélanges formation show a main sense of movement quartzose turbidites are interbedded in places, with deep- ranged from the top-to-the-NW to the-SW for the succession water successions, composed by radiolarites, shales and western of the Axios/Vardar marginal edge on the top of the volcanoclastics of Jurassic age. Medium to coarsely basic- Pelagonian and top-to-the-NE for the succession eastern intermediate sills intrude in places these sedimentary sequences of the Axios/Vardar marginal edge on the top of the Serbo- [275-277,13,29,164]. Macedonian. Sense of movement is recognized by shear sense Fig21. indicators, as σ- and δ-clasts, shear bands, and asymmetric boudinages, folds and thrusts vergence. It is interpreted as Very well structurally maintained and representative Mid-Late the kinematics, related to the ophiolites and mélanges nappe Jurassic ophiolitic mélanges sequences are the Avdella and thrusting and their finally emplacement on the Pelagonian and Vourinos mélanges in the Pindos and Vourinos mountainous Serbo-Macedonian continental margins during the Mid-Late region, respectively [276,37,40,17]. In Orthrys mountain, as Jurassic [33,195,13,27-29,5,58-61,56-57,28,150,198,164]. well as in the Axios/Vardar zone at its both western and eastern The emplacement on the Pindos flysch together with the marginal parts, similar ophiolitic mélanges formations are also overlain ophiolites, clearly westwards directed, belongs to described [168,278-279,49-50,195,19,56-57]. the younger Tertiary tectonics of the Hellenides, related either The mélanges sequences are characterized by an intensive to compressional or extensional tectonics [275-276,47,280- fold and thrust belt deformation as well as sheared matrix and 281,17]. During this Tertiary tectonics the ophiolite nappe they are sandwiched on the one hand between the External together with the underlain ophiolitic mélanges were simply Hellenides Pindos flysch at the bottom and the ophiolite belt at detached on the External Hellendes flysch with any important

J Geol Geosci 26 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 20: The SSW ward migration of the Late Cretaceous to present day arc-type magmatic activity in the Hellenic arc with respect to the main tectonic units of southeastern Europe and eastern Mediterranean region is shown (Kilias et al. 2011). Abbreviations as in Fig. 3.

effect or reworking on the older Jurassic inherited nappe destruction of the Neotethyan ocean floor (Meliata-Axios/ thrusting structures [47,280,155,28,150,198]. Vardar ocean; [13,27-29,5,58,150,198,164] This Mid-Late Jurassic ophiolitic mélange sequence was Fig22. interpreted as a synorogenic, sedimentary sequence, deposited Amphibolitic sole formations always of 180-170Ma [282,177], in progressively formed Mid-Late Jurassic basins at the front tectonically incorporated inbetween all ophiolite belts shows of the advanced ophiolites thrust sheets, following the Early- clearly this Early-Middle Jurassic intra-oceanic subduction Middle Jurassic and intra-oceanic subduction and partly event, only in a single ocean basin and this should be the

J Geol Geosci 27 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 21: Geological-structural map and representative cross-section of the Pindos ophiolites and the tectonically underlain Mid-Late Jurassic Avdella ophiolitic mélanges that are tectonically emplaced on the Paleocene-Eocene Pindos flysch. Outcrops of the sedimentary formations of the western molassic Mesohellenic trough and its tectonic boundary with the basement rocks (ophiolites, Late Cretaceous limestones and Pindos flysch) are also shown (based on Jones and Robertson 1991, 1994, amvakaV et al. 2006, 2008). Abbreviations as in Fig. 3.

Neotethyan Meliata-Axios/Vardar ocean between Apulian and The Late Jurassic to late Early Cretaceous Sedimentary European plates e.g. [11,13,27-29,30,15,22]. Series Ophiolitic mélanges of similar composition and Mid- Here can be distinguished two main sedimentary formations Late Jurassic age are also described by several authors, (the “first” and “second” formations), both deposited in in the northern continuation of the Hellenides ophiolites different times above the Late Jurassic obducted ophiolite belt, in the Albanian Mirdita ophiolite belt and the Dinarides including the Mid-Late Jurassic ophiolitic mélanges. e.g.[178,13,27-29,17,164]. These mélange formations were The “first formation” comprises shallow-water fossils interpreted as radiolaritic-ophiolitic wildflysch [13,29] and rich platform limestones of Kimmeridgian-Tithonian age, these correspond to similar sequences known from the eastern unconformably deposited on the ophiolites, directly after Alpen region (Hallstatt mélanges; [283].

J Geol Geosci 28 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis their emplacement on the continental margins of the Apulia Late Jurassic shallow-water carbonate platform. This (Pelagonian) and Europe (Serbo-Macedonian), defining formation forms a very complicated reefslope rocks unit simultaneously the upper limit of the ophiolites nappe stack but very important for the explanation of the structural- as Oxfordian/Kimmeridgian age`s [13,29,284,173,17,19]. geotectonic evolution of the Hellenides. It contains mainly, Furthermore, oolitic limestone layers constitutes also in a large number of carbonate components from polymictic some places a common compositional component of the mass-flows of the intensively eroded Late Jurassic shallow- lithostratigraphic succession. This Late Jurassic shallow water carbonate platform, “the first formation”, as well as of water carbonate formation today remains only as small rests the underlain ophiolites and basements rocks (e.g. Pelagonian on its basis, while its greater mass is eroded or in places it is or Serbo-Macedonian Triassic-Jurassic carbonate platform). totally eroded. Its age and existence is proven by the dating Radiolarites clasts occur also as components in the mass-flows. of its eroded compositional material contained as carbonate As components of the eroded Late Jurassic carbonate platform clasts and blocks in the “second mass-flows formation” dominate resedimented bioclasts of reefal limestones, shells, which has been dated as Late Jurassic-Early Cretaceous age stromatoporoids, corals, brachiopods, foraminifera, crinoids [13,5,58,93,174,284,27-29,164,173]. and sponges. Some fragments are coated and encrusted [13,29,174]. Calpionellids bearing pelagic limestones, which Fig23. dated as Late Tithonian to Early Berriasian [182,285] followed The “second formation” rests also unconformably, directly on by calcareous-siliciclastic turbidites of Late Berriasian top of the ophiolites or in places on the previous described age [18] overlain the mass-flows sequence. The whole

Figure 22 I to XII: Field photos of structural and compositional features of the ophiolite belt and the ophiolitic mélanges, as well as the deep see sedimentary sequence of the ?Sub-Pelagonian zone, underlain the ophiolites and ophiolitic mélanges (modified after Kilias et al. 2016). Sense of shear, indicated by arrow and the corresponding tectonic events are shown on each photo. The Early-Middle Jurassic ophiolitic sole, formed during the Jurassic Neotethyan intra-oceanic subduction between the hot overriding lithospheric mantel (the serpentinites) and the ophiolitic mélanges is also shown (X, XI). The (I, II, III, XII) photos are referred to the ophiolites of the Axios/Vardar zone along the eastern Pelagonian margin and the (IV, V, VI, VII, VIII, IX) photos to the Pindos ophiolite belt and ophilolitic mélanges, as well as the ?Sup-Pelagonian pelagic sediments along the western Pelagonian margin. Abbreviations as in Fig. 3.

J Geol Geosci 29 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis succession, of the mass-flows deposits with the Calpionellids province), they show an identical stratigraphical succession, limestones was dated as Late Jurassic-Early Cretaceous the same sedimentary features and components composition age`s (?Kimmeridgian-Tithonian to Berriasian-Valanginian) and were dated with the same stratigraphic age: I. Late [13,29,284,173-174,93]. Moreover, in some places the Jurassic (Kimmeridgian-Tithonian) for the first intensively stratigraphic succession through shallow-water carbonate eroded shallow-water carbonate platform formation and II. platform and flysch-like deposits reaches until the Aptian/ Late Jurassic-Early Cretaceous (Tithonian-Valanginian and Albianb[168-169,286,13,29,19,93,174,284,13,29,164]. in places to Aptian/Albian) for the second one, defining as Kimmeridgian the emplacement upper limit of the obducted Where these both Late Jurassic and Late Jurassic-Early ophiolites, everywhere [13,29,284,19,93,174,164]. Therefore, Cretaceous sedimentary formations were mapped on top of the it show clearly the same emplacement age of all Hellenides obducted ophiolites, in several localities of the Alpine orogenic ophiolite belts, either they are displayed at the western or belt from the Alps, Dinarides Albanides until the Hellenides eastern Pelagonian parts, even at the Serbo-Macedonian margin e.g. western and eastern boundaries edges of the Pelagonian and they should derive also from a similar palaeogeographic nappe, Axios/Vardar zone and Serbo-Macedonian/Rhodope oceanic provenance area.

Figure 23: Field photos of the Late Jurassic and Late Jurassic-Early Cretaceous carbonate sequences on the top of the Late Jurassic obducted ophiolites on the Pelagonian and Serbo-Macedonian continental margins (Kostaki et al. 2013, 2014, Kilias et al.2016). I. The transgression of the Upper Jurassic-Lower Cretaceous carbonate neritic and clastic sediments over the Axios/Vardar Paionia ophiolite belt at the Serbo-Macedonian margin. II, III. The carbonate clasts and the thin carbonate layer at the base of the Late Jurassic-Early Cretaceous sedimentary sequence are rich in fossils representative to a Late Jurassic fauna collection. Axios/Vardar zone, Paionia Subzone, Serbo- Macedonian margin. IV, V, VI, VII. The Late Jurassic-Early Cretaceous clastic and carbonate semi-pelagic sediments on top of the Vourinos ophiolites complex at the western Pelagonian flank. Clastic sediments with small belemnites fragments (IV) and calpionellides bearing turbidities layers (V), are distinguished. Furthermore, the late Early Cretaceous compressional D2 event related to subisoclinal, asymmetrical folds is shown (VI, VII). VIII, IX. The contact between the Late Jurassic shallow water limestones and the Zygosti ophiolites, which form the W-ward continuation of the Axios/Vardar Almopia ophiolites obducted on the Pelagonian margin (VIII). Fauna from the rich fossiliferous neritic Late Jurassic limestones at the Zygosti stream, covering the obducted ophiolites belt on the Pelagonian continent (IX) (based on Kostaki et al. 2013, 2014, Kilias et al. 2016).

J Geol Geosci 30 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Fig24. deposits containing components of the eroded Late Jurassic carbonate platform, ophiolitic debris and crystalline carbonate The relationships between these both successive events, rocks shows an uplifting process, associated possibly with first, the intensive erosion of the Late Jurassic shallow-water extension and crustal exhumation during the Late Jurassic- carbonate platform on the top of the obducted ophiolites belt Early Cretaceous in the Internal Hellenides, including the and second, the Late Jurassic-Early Cretaceous mass-flows basement rocks (e.g. the Pelagonian and Serbo-Macedonian

Figure 24: Components of the Late Jurassic-Early Cretaeous polymictic mass-flows in the Late Jurassic-Early Cretaeous sedimentary sequence: I. Rudstone with different clasts and Labyrinthina mirabilis Weynschenk (width: 0.5 cm). II. A fragment of Griphoporella jurassica (Endo) (width: 0.25 cm). III. Neoteutloporella socialis (Praturlon) (width: 0.5 cm). IV. Boundstone with Thaumatoporella sp (width: 0.5 cm). V. Boundstone with Perturbatacrusta leini Schlagintweit and Gawlick (above) and Labes atramentosa Eliasova (below) (width: 0.5 cm). Components from the Late Jurassic-Early Cretaeous turbiditic sequence of sandstones with intercalated coarse-grained mass flows: VI. Anchispirocyclina lusitanica (Egger) (width: 0.5 cm). VII. Grainstone with different clasts and Salpingoporella pygmaea (Gümbel) (width: 0.5 cm). Components from the polymictic conglomerate in the Late Jurassic-Early Cretaeous sedimentary sequence: VIII. Metamorphosed shallow- water clasts of most probably Middle Triassic age containing foraminifera (width: 0.5 cm). Microfossils from the shallow-water Late Jurassic- Early Cretaeous sedimentary carbonates: IX. Griphoporella cretacea (Dragastan) (width: 0.5 cm). X. Boundstone with Suppiluliumaella aff. methana Dragastan and Richter and debris of Selliporella neocomiensis (Radoicic) (width: 0.5 cm). XI. Linoporella aff. capriotica (Oppenheim) (width: 0.25 cm). XII. Furcoporella? vasilijesimici Radoicic (width: 0.25 cm). (Kostaki et al. 2013, 2014).

J Geol Geosci 31 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis basements with their Triassic-Jurassic platform carbonate of the Hellenic orogeny [119,67-69,72-73,214-215,24- cover) and the ophiolite belt [5,58,28,150,198]. 26,163,287,76,9-10,142]. The Late Cretaceous Shallow-Water Carbonate Formation The Tertiary kinematic pattern of extension and compression tectonics appears to be very complicated, but nevertheless for This formation deposited uncomformably upon the all pre- both cases, compressional and extensional, the recognized Late Cretaceous geological units and structures of the Internal stretching lineation is roughly perpendicular to the Hellenic Hellenides, beginning with the Cenomanian transgression. arc. So that the stretching lineation is NE-SW trending at So that, we meet it transgressively, on the Late Jurassic the western and northern orogen parts until N-S trending at obducted ophiolite belt, the Triassic-Jurassic Pelagonian and its center parts. For the compression deformational events Serbo-Macedonian platform carbonate covers, the pre-Late a main SW- to S-ward movement direction is recognized Cretaceous Axios/Vardar rocks sequences and the CRB- respectively. The sense of shear during the extensional sedimentary series, accordingly. The formation is composed stages of deformation and the nappes’ collapse seems to be mainly by neritic carbonate deposits terminated with a late the same with the compressional ones but in some places an Late Cretaceous-Paleocene typical flysch sedimentation, opposite top-to-N- to NE-sense of movement has been also known as the flysch of the Internal Hellenides. recorded [211-212,67-69,24-26,163,226,148,214-215,4,9- A representative stratigraphic column of the formation, from 10,20-21,142]. Additionally bivergent NW- and NE-wards the bottom to the top, is given at the following. The base to N- and S-wards nappes collapse is recognized in some of the Late Cretaceous succession form a few meters thick orogen provinces, indicating in these cases an important conglomerates. They are dominated by clasts of marbles, component of bulk coaxial deformation during extension and ophiolites and schists, in some places with matrix of reworked exhumation processes of the deep crustal levels [67-69,72- ophiolitic material or thin layers of terrigenous ophiolitic fine- 73,138,132,4,206]. grained material and shales. The succession is continued with Fig25. thin dolomitic layer pass upwards into intercalations of thin- to medium-bedded bioclastic, neritic limestones, mudstones, Late Jurassic-Early Cretaceous Deformational Event (D1) terrigenous sandstones and redeposited limestones. In places and Jurassic Associated Structural Processes debris flows material rich in limestones clasts is also observed The D1 event is clearly imprinted on the Internal Hellenides, inbetween the limestones layers. In the upper-most part, semi- including the Pelagonian nappe, the Sup-Pelagonian zone as pelagic limestones dominate and the rocks show a deepening it is defined, the Axios/Vardar zone, the Circum-Rhodope belt of the basin, until the finale deposition of the Maastrictian- and the Serbo-Macedonian massif [49-50,2,245,214-215,5- Danian turbiditic deposits. The overall thickness of the Late 6,58,33,195-196,163]. No clear evidences for the D1 event Creataceous carbonate succession ranges accordingly, from a have been recorded in the Rhodope metamorphic province, few meters to ~2km [168,49,179-180,35,19]. due to the strong overprinting of the younger deformational Deformation and Kinematics events affected this province. During the Alpine orogeny, the Hellenides were affected by The D1 event is dated of Late Jurassic-early Early Cretaceous a complicated multiphase deformation and metamorphism age (150-130Ma; [163,288], characterized by a penetrative history, recorded in six main (D1-D6) deformational events syn-metamorphic foliation (S1) associated with residual from the Middle Jurassic to present. In some places in the forms of isoclinals recumbent, as well as sheath folds (F1), Paleozoic basement rocks of the Internal Hellenides an older which deforms a pre-existing foliation (S0). The F1-fold axes deformational event of Ercynian age is recognized, however develop parallel to the mineral stretching lineation (L1) which strongly overprinted by the younger Alpine deformation usually trends NE-SW but in some places a NW-SE trending [2,159,214-215,5-8,58-61,93]. is also recognized, as for example in the lower Pelagonian In a general view, during the Alpine orogeny in the Hellenides, segment in Voras Mountain and the Circum-Rhodope belt, compression, nappe stacking and crustal thickening alternated as well as in Paleozoic basement slices incorporated in the successively through time with extension and orogenic Axios/Vardar zone [163,5,58]. No clear kinematic indicators collapse that was leading to exhumation of deep crustal levels, of the D1 event have been preserved, because the D1- crustal thinning and the formation of tectonic windows and/ structures have been strongly overprinted by the subsequent or metamorphic core complexes. The exhumation structural tectonics. However, in few places where the D1 kinematics processes were accordingly evolving from ductile to brittle is recognized, a main sense of movement top-to-the-SW deformation conditions. An S- to SW-wards migration of the or top-to-the-NE may be reconstructed. NW-ward sense of dynamic peer compression vs extension is clearly recognized movement is also recorded [214-215,5-6,58,33,195-196,55- during the Tertiary Alpine orogenic stages in the Hellenides. In 57]. Furthermore, an important, bulk coaxial component of the any case extension and crustal uplift follow compression and D1 deformation is also recorded [214-215,5-6,58]. The syn-D1 nappe stacking or they act simultaneously in different sections mineral parageneses, also identified in the L1-stretching

J Geol Geosci 32 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 25: In comparison, the main deformational events recorded in the External and Internal Hellenides from the Early Triassic to recent. Shortening alternated with extension through the time. Compressional events are related to nappe stacking, crustal thickening and high- pressure metamorphism, while extensional ones are related to tectonic denudation, low- to high-temperature metamorphism, isostatic rebound, crustal thinning and exhumation of deep crustal levels (see also Figs. 28, 29). The main sense of movement for each event as it was deduced by shear sense indicators and kinematic analysis, is shown in the Schmidt diagrams with arrows (lower hemisphere equal-area projections). (Kilias et al. 2010, Katrivanos et al. 2013).

J Geol Geosci 33 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis lineation, show metamorphic conditions from the greenschist extension has been also described in the Betic cordelleras to the amphibolite facies, from the structurally higher to the (Spain) by [291-292], as well as in the Alps (Austroalpin structurally deeper crustal levels, respectively [245,5-6,58]. domain) by [293,85]. High-pressure metamorphism in the Internal Hellenides, Late Early Cretaceous Deformational Event (D2) predating the D1, has been suspected in several works [288- The D1 and older structures are strongly overprinted by a 289,260,79-80,163,5,58,82-83] but nonetheless without any younger, contractional, D2 syn-metamorphic deformation, clear syn-metamorphic structural evidence due to the strong recognized everywhere in the Internal Hellenides zones. The overprinting by the younger tectonics. The pre-D1 high- D2 event has strongly affected all pre-Late Cretaceous units, pressure metamorphic assemblages occur only as relics and they including the Paleozoic basement rocks with their Triassic- are clearly related to compression and subduction processes or Jurassic carbonate platform sediments cover and outer shelf tectonic overpressure and continental crustal sinking due to pelagic sediments, as well as the strongly eroded Late Jurassic overloading and nappe stacking in an arc-continent collision shallow-water carbonate platform sediments and Late Jurassic- setting and the ophiolites obduction [5,58,19,6]. Pre-D1 high- Early Cretaceous mass-flows and flysch-like sedimentary pressure metamorphic assemblages have been dated of early series initially deposited on top of the obducted ophiolites, Late Jurassic age (>150Ma) [289,260,163,288,5,58]. clearly indicating a late Early Cretaceous age for the D2 event Here, we must also mention the very important formation [5-6,58-60,176,63] D2 contractional structures are sealed of the amphibolitic sole of late Lower-Middle Jurassic age further by the Late Cretaceous transgressive, neritic carbonate (180-170Ma) [282,177], predating the D1 event and the high- sediments. Furthermore, isotopic dating analyses show a pressure metamorphism but closely related to its evolution similar of late Early Cretaceous age deformation in Pelagonian and the subsequent Late Jurassic ophiolites obduction on and Axios/Vardar zone Albian-Aptian, 125-110Ma; [163,288]. the continental margins of the Pelagonian and the Serbo- D2 is characterized by well-developed, in micro- and macro- Macedonian massif, towards West and East, respectively scale, asymmetric, recumbent to overturned, tight to isoclinal [33,195-196,13,29,5,58,30,15,22,28,150,198]. Amphibolitic folds (F2), refolding both the S1-folation and the isoclinal D1 sole formation accompanies with the same ages the obducted folds. A new S2 foliation was developed parallel to the F2 ophiolites belt either at the western or the eastern Pelagonian folds’ planes, forming in places a well-recognized crenulation part, as well as the Serbo-Macedonian/Rhodope province, cleavage with the S1 foliation. Usually due to intensive indicating at least its simultaneous formation and a similar rotation of S1 along the S2 the S1 is totally parallelized to S2 origin`s source and this was the Middle Jurassic intra-oceanic foliation and as a result the two foliations coincide so that only subduction in the single Neotethyan Axios/Vardar ocean basin one foliation can be observed. [260,13,5,58,30,15,84,28,150,198]. Intra-oceanic subduction The F1 and F2 folds axes are developed mostly parallel to is associated with Mid-Late Jurassic island arc magmatism each other, while in some places the F2 folds show even a now represented mainly as slices in the rocks sequences of the scattering of their trend, from NW-SE to NE-SW. We attribute Circum-Rhodope belt and the Axios/Vardar zone [162,258- this scattering of the trend of the F2 folds to a progressive 259,6,61]. Furthermore, the previous described Mid-Late rotation towards the stretching direction and the X-strain Jurassic ophiolitic mélanges were deposited and intensively axis developed during the D2 deformation. The stretching imbricated in basins at the front of the advanced ophiolites lineation trends mainly NE-SW but in some cases a NW-SE during their inneroceanic thtrusting and subsequently obduction trending is observed, as it is concluded by the development on the Pelagonian and Serbo-Macedonian continental margins. of the syn-D2 metamorphic mineral parageneses on the The upper limit of the ophiolites obduction, as it is previous S2 foliation planes. The sense of shear during the D2 is mentioned, is defined as Kimmeridgian age`s, much earlier as accordingly to the stretching lineation, mainly top-to-the-SW previous assumed [276,13,29,284,173,280,290,17,19]. in the Pelagonian and Axios/Vardar zone and to NE-ward in Taken into account, the previous described Late Jurassic the Serbo-Macedonian province. Additionaly, NW-ward sense carbonate platform sediments on the top of the obducted of movement is also observed mainly in the lower Pelagonian ophiolites and the subsequent Late Jurassic-Early Cretaceous segment and the Axios/Vardar zone. We concider this geometry resedimented mass-flows sedimentary series, as well as the of deformation of two sense of movement directions, NW-ward P/T/t metamorphic path during the D1 evolution, we suggest and SW-ward, as the result of a transpresional tectonic regime an uplifting process during the Late Jurassic-Early Cretaceous [67-69,33,195,5,58,30,15,22,294,176,63] M2-metamorphic for the Pelagonian and Serbo-Macedonian continental margins mineral parageneses show metamorphic conditions in the respectively, just after the Late Jurassic Neotethyan Axios/ greenschist facies [163,5-6,58]. Vardar ophiolites obduction (Callovian-Oxfordian) and the Fig26. high-pressure metamorphic event. Additionally, uplifting was Early Late Cretaceous Deformational Event (D3) possibly related to slab break-off of the subducted lithosphere [55]. Isoclinal, recumbent folds during synorogenic crustal The D3 is recognized in the Pelagonian nappe pile and its

J Geol Geosci 34 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis metamorphic basement sheets in the Axios/Vardar zone (e.g. to isoclinal folds and syn-metamorphic S4 schistosity, today Peternik and Paikon basement rocks). No clear evidences residual remainιng. During this D4 contractional tectonics the of the D3 structures have been observed in the Serbo- middle Rhodope Sidironero unit was overthrusted the lower Macedonian massif at the eastern edge of the Axios/Vardar most Rhodope Pangaion unit. On the contrary, the D4 ductile zone. D3 is related to extension and has been dated of early structures are extensional in the upper-most structural nappes Late Cretaceous age (110-100 Ma) [163,5,58]. The D3 of the Serbo-Macedonian/Rhodope metamorphic province, i.e. structures form discrete, mylonitic shear bands with a well- the Kimi and Vertiskos units and these are mainly down-dip developed S3-mylonitic foliation dipping mainly towards NE. verging ductile shear zones [168,49-53,213,175,237,30,15- The associated L3-stretching lineation also plunges down dip 16,5-8,58-61,93,22,28,150,198]. to the NE. The D3 shear bands are usually characterized by The D4 deformation, both ductile and brittle, took place during dynamic recrystallization of quartz and growth of chlorite and the Paleocene-Eocene, as it is concluded by numerous isotopic sericite. The sense of shear during the D3 was mainly identified dating ages and lithostratigraphic-structural relationships down-dip towards NE, although in few cases an opposite, [168,2,49-53,163,179-180,5-8,58-61,93,22]. The ductile again down-dip, towards SW sense of shear is also observed, compressional D4 structures in the lowermost Pelagonian related to SW-ward dipping of the S3-foliation and SW-ward parts, the Internal high-pressure belt in Olympos-Ossa- plunge direction of the L3 stretching lineation [163,288,5,58]. Cyclades and the Rhodope Sidironero unit, are all associated In contrast to the described D3 extensional structural setting to high-pressure metamorphic conditions. On the contrary, in the Pelagonian and Axios/Vardar basement rocks, ongoing at the same Paleocene-Eocene time the ductile extensional NE-wards subduction processes of the Axios-Vardar oceanic D4 structures and the final exhumation of the upper Serbo- lithosphere remnants under the European continental Macedonian/Rhodope nappes (i.e. Vertiskos and Kimi units, margin, including the Serbo-Macedonian/Rhodope and cooling ages ~80-65 and 65-45Ma, respectively; [236] took Sredna-Gora massifs, is revealed by Late Cretaceous calc- place under greenschist to amphibolites facies metamorphic alkaline volcanic-arc magmatism along the southwestern conditions and partly migmatization and granitoids intrusions European continental margin (Fig. 2, 20), as well as high- [65,51-54,214-217,6-8,93,236]. to ultrahigh pressure metamorphism in the eastern Rhodope A main SW-ward sense of movement is recognized for all D4 units [265,195,267,190,22,43]. Therefore, a Late Cretaceous structures, either they are related to contraction or extension contraction (ca. 80Ma) [22,42,43] at the eastern-most area of and ductile or brittle. In some cases, NE-wards back-direction the Internal Hellenides in the Serbo-Macedonian/Rhodope of sense of movement during the D4 event, is also identified province, just after or about simultaneously with the D3 early in the broader area of the internal Hellenides, the same, if the Late Cretaceous extension is inferred. structures are of contractional or extensional setting [168,49- Paleocene-Eocene Deformational Event (D4) 50,179-180,214-215,5-8,58,93,54,30,15-16]. The D4 event is again characterized by a very complicated Oligocene-Miocene Deformational Event (D5) evolutionary history. It is related to ductile up to brittle In the Internal Hellenides, the D5 structures are generally related deformational conditions and intense folding and imbrication, to extensional tectonics and exhumation of deep structural as well as nappes denudation and orogenic collapse, accordingly. units either in form of tectonic windows or metamorphic core The D4 structures are well recognized in the Pindos zone of the complexes of Oligocene-Miocene age. They are recognized in External Hellenides, as well as in the Pelagonian nappe pile, the Olympos-Ossa, Rizomata and Paikon windows, as well as the Axios/Vardar zone and the Sebo-Macedonian/Rhodope in the Pangaion and Cyclades metamorphic complexes [211- metamorphic province of the Internal Hellenides. Ductile 212,227,53,115,217-218,246,16,6-8,93,59-61]. and brittle deformation during D4 take place simultaneously on the several structural parts levels of the Hellenic orogenic The D5 structures have been dated as of Oligocene-Miocene belt. So that, ductile deformation in the Serbo-Macedonian/ age e.g. [163,5-8,58,93] and in the Internal Hellenides are Rhodope metamorphic province and the lower structural characterized by normal detachment faults and mylonitic levels of the Pelagonian nappe, including the Paleocene- rocks formation in the structurally lower crustal levels. Brittle Eocene Olympos-Cyclades high-pressure belt takes place at to semi-ductile deformation is recorded at the structurally the same time with brittle deformation in the upper structural higher crustal levels (e.g. upper part of the Pelagonian levels of the Pelagonian nappe pile, the Axios/Vardar zone and nappe in northern Greece including the Paikon window) the structural province of the External parts of the Pindos zone. and ductile, related to green-schist to amphibolite facies The brittle deformation is characterized by intense crustal metamorphic conditions until migmatization at the lower imbrication and asymmetrical kinck-folds. Additionally, the ones (e.g. Olympos-Ossa and Rizomata windows, Cyclades related ductile D4 structures are contractional in the Rhodope and Rhodope Pangaion metamorphic core complexes). Here, Sidironero unit, the Pelagonian nappe and the Olympos- should be mentioned the Eocene-Oligocene space time where Cyclades high-pressure belt, related to asymmetrical, tight the middle Rhodope Sidironero unit was exhumed during

J Geol Geosci 35 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 26 a: Schematically, the geometry and kinematics of the Alpine deformation in the Internal Hellenides (Pelagonian nappe, Axios/Vardar zone and Serbo-Macedonian/Rhodope metamorphic province). The relationships between the several tectonic events and their dynamic (compression or extension) in the several geotectonic domains are shown. The tectonic boundary between Europe and Pelagonian (Apulia) is also noted. Gray arrows and lines illustrate the progressive stages of the Tertiary extensional tectonics related to uplift and exhumation of deep crustal levels. b. In mega-scale 3D-tectonic sketch of the Pelagonian structure in Voras Mt. (lower Pelagonian), that is regarded as a mega- sheath fold formed mainly by the D1 and D2 events. D4 and D5 structures are also shown. Both, stretching lineations (L1, L2) and fold-axes (D1, D2) trending are oriented parallel to sub-parallel during the deformation. Schmidt diagrams (lower hemisphere equal-area projections) show the orientation of the tectonic structures (lineation, fold axis and foliation plane) and the associated kinematics for each tectonic event (D1 to D5) in the tectonically upper parts of the Pelagonian basement (modified after Kilias et al. 2010, Katrivanos et al. 2013, Avgerinas 2014).

J Geol Geosci 36 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis extension associated with high-temperature metamorphism, Nikolaos windows), under an isothermal decompression P/T- migmatization processes and also granitoids intrusions [214- path [296-297,111,72-74,287,76,298-299]. 217,6-8,93-94,54,30,15,22,295]. Cooling age of the Sidironero Neogene-Quaternary Deformational Event (D6) unit, as it is previously referred, was dated 42-30Ma, the same cooling age with the lower Serbo-Macedonian Kerdylia The D6 event is mainly related to extension in all the Hellenides’ unit [236]. This Eocene-Oligocene extensional stage of the area, and took place under brittle conditions. The D6 structures Rhodope province was further continued to the described D5 overprint all the previously described structures and represent Oligocene-Miocene extension. On the contrary, during the the final deformational stages of the orogen. At this stages, the same Eocene-Oligocene time, clearly related to compressional compression and the orogenic evolution migrated further SW- tectonic, the Pelagonian nappe and the Olympos-Cyclades wards now into the arcuate form active Hellenic subduction high-pressure belt emplaced tectonically over the External zone southern of Crete island, related to the active Hellenic Hellenides Gavrovo carbonate platform. volcanic arc in the [300,104,206,21]. Sense of shear during the D5 event in the internal Hellenides The D6 structures are characterized by high-angle, both is down-dip mainly towards SW. Oposite sense of movements dip-slip and oblique-slip normal faults, as well as strike-slip towards NE has been also observed in a few places (e.g. faults, while some of them are related to the development of Olympos-Ossa window), indicating a bivergent orogenic the Neogene-Quaternary basins in the Hellenides [97-99,301- crustal deformation during the D5 [67-69,227,115,24- 303,212,90-91]. Many of the D6-faults produced significant 26,163,214-215,4-6,58]. tectonostratigraphic gaps juxtaposing higher tectonic nappes against lower ones [5-6,58-60]. Furthermore, some of the D6 On the contrary to the D5 structural setting in the Internal faults are still active, often associated with strong earthquakes Hellenides, a belt of intense folding and thrusting, in form of [212,304-306,90-91]. a thin-skinned type tectonic, was developed in the External Hellenides at the same Oligocene-Miocene time, clearly Geotectonic Reconstruction of the Hellenides, Discussion related to compression and crustal stacking. An also main According to the described structural architecture and evolution SW-ward sense of movement is recognized by the thrust from the Permo-Triassic to recent, as well as correlationships faults geometry and the asymmetric verging of the folds. between the deformation history and the tectonostratigraphic Thrust and fold structures strike mainly NW-SE. Back- setting of the several Hellenic domains or units (Internal and thrusting top-to-the NE is often observed in places. During External Hellenides), we attempt in this chapter to reconstruct the Oligocene-Miocene, the Gavrovo zone, together with the Alpine geotectonic evolution of the Hellenic orogenic belt. the overlain during the Eocene-Oligocene Pindos nappe and Additionally, we discuss the several views that dominated in the Pelagonian nappe with the Late Jurassic obducted Neotethyan modern international bibliography, referred to the Hellenides ophiolites, were all thrusted towards SW over the Ionian zone, geological history. We have to emphasize that, although a lot of following the general Tertiary SW-wards orogenic migration scientific researches have been published about the structural of compression. Furthermore, the Pindos zone, possibly due evolution of the Hellenides, many questions still remain open, to an out-of-sequence thrust fault, was again thrusted in places and hence their geotectonic reconstruction is in some respects further to the west directly over the Ionian zone during the hypothetical. Early Miocene, covering completely the Gavrovo zone and its contact with the Ionian zone [44,46-47]. Continental rifting and opening of the Neotethys ocean basin start during the Permo-Triassic, possibly related to the closure Fig27. of the Paleotethys further to the North [143,8] Formation Additionally, HP/LT metamorphism of Oligocene-Miocene of oceanic lithosphere started in the Early-Middle Triassic age and compressional tectonic causing nappe stacking [178,172,18,13,284]. Continental rifting is associated with and crustal thickening has been recognized in the External bimodal volcanic and neritic-clastic sediments deposition along Hellenides in the Peloponnesus and Crete island [71-73,111- the arisen continental margins, as well as A-type leucocratic 112,75-76]. Here, parts of the Ionian zone together with the granitoids intrusions in the Paleozoic basement rocks. The Phyllite-Quarzite unit of unknown origin were subducted northeastern continental margin of the Apulia, including during the Oligocene-Miocene below the Gavrovo zone and the Pelagonian continental domain, and the southwestern metamorphosed in HP/LT conditions. So that compression continental margin of the European continent, including the and extension take place again simultaneously in different Serbo-Macedonian and Sredna-Gora/Strandja massifs were geotectonic places in Hellenides during the Oligocene-Miocene progressively developed with the Neotethyan Meliata-Axios/ (D5 event). HP/LT metamorphism and nappe stacking were Vardar ocean basin opening in between the two margins. progressively followed by Early-Middle Miocene extensional Carbonate platform to pelagic sediments and turbidites were tectonic, nappe collapse and exhumation of the high-pressure progressively deposited in several stages and geotectonic regime, rocks units in form of a series of tectonic windows (e.g. from the Triassic to the Miocene along the continental margins of Taygetos-Mani, Lefka Ori, Psiloritis, Dikti-Lathisi, Agios both European and Apulia plates [158-159,2,262-263,8].

J Geol Geosci 37 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 27: Field photos of stratigraphical sequences and tectonic structures of the External Hellenides zones. I. II. III. IV. The typical S/ SW-ward asymmetrical, tight folds of the Pindos series. Red Jurassic radiolarian cherts (Pindos Mt., I), Pelagic Cretaceous limestones with siliceous cherts layers (Pindos Mt., II), Pelagic Triassic limestones with siliceous cherts layers (South Crete island, III, IV). V, VI, VII. The Early Cretaceous (Valanginian-?Turonian) Pindos “first flysch” intensively multifolded. VIII. SW-ward Eocene-Oligocene thrust fault in the Gavrovo flysch (Pindos Mt}. IX. Oligocene-Miocene out-of-sequence SW- ward thrust fault in the Pindos zone (Pindos Mt). The Triassic Pindos limestones overthrust the Jurassic Pindos radiolarian cherts which overthrust secondary during the Oligocene-Miocene the Ionian zone, possibly due to an out-of-sequence mega-thrust fault zone; see also Fig. 3, 4 (modified after Kilias et al. 2016).

During the Early-Middle Jurassic, part of the Triassic Neotethys Fig28. ocean, the Maliac/Meliata ocean, subducted towards SE in an Due to the intra-oceanic subduction, parts of the Axios/ intra-oceanic subduction regime [11-12,22,176,63,61], which Vardar ocean basin, named Paionia ocean basin, developed progressed in an arcuate northwestward-convex subduction zone progressively during the Mid-Late Jurassic in a supra- [11-13,22]. This geometry could be caused by a further northwest- subduction position, in the back-arc basin [192,11- directed retreat of the subduction zone due to roll-back of the 12,14,18,22,61]. In the next stage, during the Late Jurassic, subducting slab [195,11-12]. Formation of amphibolite sole of a due to arc-continent collision the island arc formations 170-180Ma age [282,177] and island-arc intermediate to silicic together with the Neotethyan Axios/Vardar ocean lithosphere magmatism were related to the progression of this geotectonic and the ophiolitic mélanges were obducted towards West onto setting (e.g. the Fanos granite, the volcanics of the CRB, the the Pelagonian continental margin, which at this time was still Paikon volcanoclastic series) [162,35,30,15,6,22,61]. The Late connected with the Apulia plate [13,5,58,18,22,176,63] and Jurassic calc-alkaline granites today found as othogneisses in the also towards East, together with the CRB volcanosedimentary middle Rhodope Sidironero unit [219] and the Stip-Axios massif series, onto the upper Serbo-Macedonian Vertiskos unit, as part of the upper Serbo-Macedonian Vertiskos unit [189-190], that consisted part of the European continental margin should be related to the progression of these Jurassic subduction [54,30,15,22]. This simultaneous, opposite geometry of processes, representing the plutonic infrastructure of the volcanic kinematics on both, western and eastern side of the Meliata- products [195,22]. At the front of the overriding upper oceanic Axios/Vardar ocean basin, Apulia and Europe respectively, lithosphere, the Mid-Late Jurassic ophiolitic mélanges associated was interpreted by the progressively, strong curvature of this with deep-water sediments were deposited, such as the Avdella Jurassic intra-oceanic subduction zone [30,15,22]. and Orthrys mélanges in Pindos mountain and other equivalent The Late Jurassic high-pressure metamorphism, predating the formations in the Alpine orogenic system in Europe (Alps, D1 Late Jurassic-Early Cretaceous deformation, is ascribed Dinarides, Albanides) [275,13,30,15,17-19,22,164]. They, to this nappes stacking deformational stage. Parts of the during their Jurassic emplacement progression on the continental continental margins and the arc-formations were detached and margins of the Apulia and Europe plates, were strongly imbricated buried beneath the advancing, obducted part of the Neotethyan and folded, forming a typical tectonosedimentary sequence. Are oceanic lithosphere in response to the continental margin- recognized isoclinal recumbed folds refolded by asymmetric tight trench collision and were metamorphosed in high-pressure folds, generally vergent West- and East-wards, respectively. conditions [5-6,58,17,22].

J Geol Geosci 38 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

During the D1 progression the high-pressure metamorphic Cretaceous has been also recorded by [176,63], indicating rocks came up again to shallower crustal levels and were a high grade temperature flow in places during the D2. The strongly deformed simultaneously with a greenschist- to Beotian flysch of Early Cretaceous age [155], as well as some amphibolite facies metamorphism, which is well exposed in ophiolite mélanges occurrences, which were deposited at that the Pelagonian nappe, as well as in the Serbo-Macedonian time, should represent the sedimentary infill of the foreland massif [245,163,288,5-6,58]. Furthermore, during the Late basins formed at the front of the D2 thrust sheets. Early Jurassic-Early Cretaceous and/or immediately after that, Cretaceous high-pressure metamorphism referred by [77,86] the accumulated Late Jurassic shallow-water sedimentary for the Rhodope province could be explained as a consequence carbonate platform on the top of the obducted ophiolite nappe, of the D2 compression. just after their emplacement, clearly determining the upper limit The crustal thickening of the late Early Cretaceous times (D2 of the ophiolite emplacement in the Kimmeridgian/Tithonian, event) was followed by an early Late Cretaceous extension was partly totally eroded [13,284,27-29,5,58,156]. The (~100Ma; D3 event), which was associated accordingly eroded components were unconformably redeposited again, with crustal unoofing and basins’ subsidence, wherein the during the Late Jurassic-Early Cretaceous, on the ophiolites Late Cretaceous-Paleocene carbonate series and the internal or the underlain Pelagonian or Serbo-Macedonian basement Hellenides’ flysch were deposited. Sedimentation break was rocks, as it is previous in detail described [13,27,93,174] and caused by the compressional D2 structural activity, creating a references therein. The relationships of these both erosional stratigraphic gap between the Late Jurassic-Early Cretaceous and redepositional events indicates an extensional tectonic sedimentary formations and the Late Cretaceous neritic regime and crustal unroofing during the Late Jurassic-Early sediments, with the latter lying discordantly over all the Cretaceous, as it is previous reffered. previous pre-Late Cretaceous structures [5-6,58]. The depositional ages of all these Late Jurassic shallow- A continental break-up of Apulia took place locally during water carbonates and their eroded products forming the the progression of the Late Cretaceous subduction of the Late Jurassic-Early Cretaceous mass-flow sedimentary Axios/Vardar ocean lithosphere remnants under the European formations, lying unconformably over the ophiolite rocks continental margin, including the Serbo-Macedonian Vertiskos or their underlain basement rocks, is exactly the same in all regions of their occurrences, either on the eastern and western unit and the upper Rhodope nappes. Break-up of Apulia was margins of the Pelagonian nappe or on the Serbo-Macedonian associated with the formation of a small ocean basin in the late Vertiskos unit, indicating a simultaneous emplacement of the Cretaceous in the Cyclades area, named Pindos-Cyclades ocean, ophiolites on both Apulia (Pelagonian) and European (Serbo- which separated now the Pelagonia fragment from the Apulia Macedonian) continental margins [169,172,307,13,258- [20-22,42-43]. New oceanic crust was dated at ~80Ma in the 259,93,174]. According to this evidence and additionally Cyclades area and Crete island, supporting the development of taking in account our structural works [5-6,58,61], as well as this Late Cretaceous ocean basin western of the Pelagonia [208- a lot of recent studies concerning the geodynamic evolution 209,21]. Late Cretaceous subduction is clearly indicated by the of Hellenides [14-15,30,18,22,176,63], it is inferred that all Late Cretaceous magmatic arc that was developed along the ophiolite nappes originated from a single source and this was European margin (i.e. Strandja massif and Sredna Gora zone in the Neotethyan Axios/Vardar ocean basin. Subsequently, the Bulgaria) above the subduction zone, associated progressively, ophiolite nappes should be considered as far-travelled nappes as it is already described, by a migrated SW-ward-younging on the two different continental parts of Apulia (Pelagonian) magmatic activity and roll-back of the subducted lithospheric and Europe (Serbo-Macedonian), where the ophiolites were slab [202-203,267,22,295,21-22]. Furthermore, the Late initially emplaced during the Late Jurassic. Cretaceous high-to ultra-pressure rocks (70-80Ma) recognized in between the Rhodope nappes, strongly support this Late During the late Early Cretaceous (D2; ~120-110Ma), ongoing Cretaceous subduction process [42-43]. plate convergence and possible pull of the subducted lithospheric slab, led further to outward W- to SW-vergent imbrication and During the Paleocene-Eocene the D4 compressional event folding of the whole Pelagonian nappe pile, including the follows. It is related to the final stages of the Late Cretaceous previously during the Late Jurassic obducted ophiolites, the subduction processes of the Axios/Vardar ocean under the Late Jurassic-Early Cretaceous sedimentary formations, and Europe and the subsequent development of the SW-ward the Paleozoic basement rocks, and it was generally related to a thrust and fold belt in the entire Internal Hellenides without greenschist facies metamorphism [5-6,58,93,174,176,63]. On any important metamorphic event at their tectonically higher the contrary, an E- to NE-ward sense of movement has been parts [168,49-50,5-6,58]. During this structural stage, oceanic identified for the eastern side of the Axios/Vardar ocean at the lithosphere of the subducted Axios/Vardar ocean and European same time, as it is can be explained by the proposed evolution continental origin’s segments, including the Rhodope Late of an arcuate Jurassic subduction zone in the Neotethyan Jurassic calc-alkaline arc related granitoids, following the Meliata-Axios/Vardar ocean realm [195,30,15,22]. Migmatites subducting ocean slab accreted to each with the other, forming development in the Pelagonian basement during the late Early the Rhodope Sidironero unit and the related Rhodope nappe

J Geol Geosci 39 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 28: (Without scale). Schematic crustal-scale transects showing the structural evolution of the Hellenides during the Alpine orogeny from the Early-Middle Jurassic until the late Early Cretaceous and after the Permo-Triassic continental rifting of the Pangaea and the Neotethyan ocean opening shown in Fig. 18. (modified after Kilias et al. 2010, Jahn-Awe et al. 2010, Froitzheim et al. 2014, Kilias 2018, 2019). a. Early- Middle Jurassic: intra-oceanic subduction in an arcuate, northwestward convex subduction zone, associated with formation of amphibolitic sole, ophiolitic mélanges at the front of the overriding oceanic lithosphere and island arc magmatism. New oceanic lithosphere is formed (e.g. the Paionia subzone) by back-arc spreading in the supra-subduction zone (SSZ). b. Middle-Late Jurassic (Oxfordian-Kimmerdgian): Arc-continent collision, ophiolite obduction, ophiolitic mélanges formation at the front of the advanced ophiolites on the continental margins, high-pressure metamorphism, W-ward and E-ward sense of movement and crustal imbrication at the western (Pelagonian/Apulia) and eastern (Serbo-Macedonian/Europe) marginal parts respectively of the Neotethyan realm. Subsequently, deposition of the Late Jurassic neritic sedimentary sequence on the obducted ophiolite realm. c. Late Jurassic-Early Cretaceous: Retrogression under greenschist to amphibolite facies metamorphic conditions during the Late Jurassic-Early Cretaceous and progressively possible uplifting of both continental margins (D1). Deposition of the Late Jurassic-Early Cretaceous mass-flows deposits during extension and crustal uplift. d. late Early Cretaceous (D2; Albian-Aptian): W-ward and E-ward crustal imbrication and nappe stacking at both the Pelagonian and Serbo-Macedonian margins, respectively. Syn-tectonic greenschist facies metamorphism. The future Late Cretaceous subduction zone along which the remnants of the Neotethyan Axios/Vardar ocean will be subducted under the Europe is shown by dotted, think grey line. Abbreviations as in Fig. 3.

J Geol Geosci 40 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis stacking. Finally, during the Paleocene-Eocene (D4), the entire /Rhodope metamorphic province as well as Axios/Vardar ocean lithosphere was buried, the Axios/Vardar magmatic activity, associated with extension and crustal ocean basin closed, and the European active margin was collided exhumation, take place simultaneously with compression with the Pelagonian [5-8,58,93,30,15,17,19,22]. We interpret and nappe stacking more western at the External Hellenides the described Nestos thrust zone, which has been dated with (Pindos nappe), as well as with subduction processes of the the same Paleocene-Eocene age by [30,15], as the exhumed small Pindos/Cyclades ocean and the A-type subduction in tectonic contact between European`s (Serbo-Macedonian/ the Olympos/Ossa area under the Pelagonian and the internal Rhodope nappes stack ) and Apulia`s (Pelagonian) fragments. Hellenides nappes pile [53,214-217,5-8,58,93,54]. As a During the D4 event, as compression and nappe stacking was continuation of this Paleocene-Eocene subduction processes, advancing towards West through time at the Serbo-Macedanian/ during the Eocene-Oligocene, the Pelagonian fragment Rhodope province, compression and possibly high-pressure and the pre-existing Hellenides’ nappe stack collided to the metamorphism were progressively followed by extension, Apulia and together with the buried Paleocene-Eocene Pindos/ nappes’ collapse mainly towards SW and gradual exhumation Cyclades high-pressure metamorphosed basin formations, of the higher to the deeper crustal nappes (e.g. initially the were thrusted onto the carbonate platform sediments of the Vertiskos and Kimi units) associated now with high-grade External Hellenides (i.e. the Gavrovo zone), which constituted temperature metamorphism and migmatites creation, as well the passive continental margin of the Apulia plate. as new adakitic magmatic activity dated as of Paleocene- Regarding the above described Jurassic to Paleocene-Eocene Eocene age (e.g. Elatia granite) [216,78,24,202,232,237,86]. architecture and structural evolution, the tectonic lower- The high-temperature metamorphism and the magmatic most Rhodope Pangaion unit should be the marginal part activity was possibly triggered by the break-off of a deep- of the Apulia`s origin Pelagonian fragment, detached from seated slab due to delamination or convective thinning of the Apulia during the Late Cretaceous and underthrusted under previously overthickened lithosphere, resulting in upwelling the European continental margin, including the Serbo- of asthenoshpheric material and flow heating [202,232,86]. Macedonian basement and its Mesozoic sedimentary cover. Fig29. The Nestos thrust zone was regarded as the tectonic contact at the deep, between Apulia`s, including the Pelagonian nappe Around the same time, during the Paleocene-Eocene, the and Europe`s, including the Serbo-Macedonian massif. The Cyclades/Pindos small ocean or part of the Pindos basin thrust zone between the Axios/Vardar formations and the Stip- subducted under the Pelagonian fragment contemporaneously Axios massif, as part of the Serbo-Macedonian massif, should with the A-Type subduction in Olympos-Ossa area further to be the western more tectonic boundary of the Europe, the the North [51-53,67-69,115,22]. Simultaneously, further to later regarding as a far travelled tectonic nappe on the Apulia the west, the external parts of the Pindos zone was strongly plate and more detail on the Apulian’s origin Pelagonian SW-wards imbricated and folded. A thin skinned tectonics, fragment. This is our one difference from the proposals by characterized this compressional tectonic of the External [148,30,15,22], that regard the Rhodope Pangaion unit as Hellenides, building up the structurally complicated Pindos part of the External Hellenides zones, being higher grade nappe. The Internal Hellenides Paleocene-Eocene high- metamorphosed due to its deeper tectonic position to the East pressure belt was formed during this subduction process below the Inernal Hellenides nappes (Serbo-Macedonian and [51-53,67-69,115,148,30,15,22], continue this high-pressure Rhodopes). Here, we should also mention that the Kesebir/ belt until the Rhodope Sidironero unit [78,81,86], suggesting Kardamos and Kechros domes in the Rhodope province, which the lower most Rhodope Pangaion unit as an exhumed part have been placed on many geological maps as equivalent to of the External Hellenides, equivalent to the Olympos-Ossa the lower Rhodope Pangaion unit, do not show clear structural carbonate platform and its Apulia`s basement. Here should be and compositional relationships with the Pangaion unit. They noticed, that Paleocene-Eocene high-pressure metamorphism do not contain the thick carbonate sequence as the Pangaion in the Rhodope Sidironero unit come in contradiction with the unit, there are overlain directly by the upper Rhodope Kimi proposed closure of the Axios/Vardar ocean at this time and the unit equivalent to the Serbo-Macedonian Vertiskos unit and described finale collision of Europe with Pelagonian fragment. the most important difference to the Pangaion unit is that, their A Late Cretaceous-Paleocene high-pressure metamorphism in cooling age was dated at the Eocene-Oligocene (40-30 Ma) the Rhodopes, related to the Axios/Vardar ocean lithosphere [236], the same cooling age given for the middle Rhodope beneath the European margin (Sredna-Gora and Srtandja Sidironero unit [54,236,30,15,22]. Regarding the described massifs), proposed recently by [42-43], would be fitted better structural and compositional features of both metamorphic with the described Paleocene-Eocene structural and magmatic domes, the Kesebir/Kardamos and Kechros domes, fit more to history of the Serbo-Macedonian/Rhodope province, and we be equivalents to the Sidironero unit, as it is illustrated on our agree with that. maps and cross-sections. Summarizing, Paleocene-Eocene high-grade temperature Eocene-Oligocene nappe stacking and crustal thickening metamorphism and migmatites formation in the Serbo- in the West, in the External Hellenides, associated also with

J Geol Geosci 41 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Figure 29: (Without scale). Schematic crustal-scale transects showing the structural evolution of the Hellenides during the Alpine orogeny from the early Late Cretaceous until the Neogene-Quaternary. CRB=Circum-Rhodope belt (modified after Kilias et al. 2010, Froitzheim et al. 2014, Kilias 2018, 2019). e. Late Cretaceous: extension during the Albian-Cenomanian (D3). Unconformable sedimentation of the Late Cretaceous shallow water carbonate series terminated in the Paleocene with the internal Hellenides flysch. Progressively, starting of the Late Cretaceous subduction of the Axios/Vardar ocean remnants under the Serbo-Macedonian margin (Europe) and formation of Late Cretaceous calc-alkaline, arc-type magmatism at the European margin, as well as Late Cretaceous high-pressure/high-temperature metamorphic belt (HP/HT). Exhumation of the upper most Serbo-Macedonian parts during the Late Cretaceous-Paleocene (Vertiskos unit). Possibly, spreading of the ?Pindos/Cyclades small ocean basin, now between the Pelagonian and Apulia. Its future Paleocene-Eocene subduction under the Pelagonian nappe is also indicated by grey line. f. Early-Late Paleogene (D4; Paleocene-Eocene/Oligocene): compression, W- to SW-ward sense of movement and intense crustal imbrication at the Pelagonian and Axios/ Vardar zone. Finale collision of the Europe (Serbo-Macedonian) with and the Apulia (Pelagonian nappe) during the Paleocene-Eocene along the Nestos thrust zone simultaneously with extension at the higher Serbo-Macedonian/Rhodopes nappes and finale exhumation of the Serbo-Macedonian and upper Rhodope Kimi unit. Formation of the Internal Hellenides high-pressure belt of Paleocene-Eocene age (Olympos-Ossa, Cyclades) due to the subduction of the small Pindos/Cyclades ocean under the Pelagonian and progressively emplacement during the Eocene-Oligocene of the Pelagonian nappe (Apulia) together with the HP/LT internal Hellenides metamorphic belt on the External Hellenides (Gavrovo zone, Apulia). Intense compression and nappe stacking in the External Hellenides Pindos and Gavrovo units. Simultaneous Eocene-Oligocene syn-orogenic extension in the Serbo- Macedonian/Rhodope metamorphic province associated with high-temperature metamorphism, migmatization and magmatism and exhumation of the middle Rhodope Sidironero unit. g. Late Paleogene-Quaternary (D5, D6; Oligocene-Miocene to recent): (D5). HP/LT metamorphism and building of the External Hellenides Oligocene-Miocene high-pressure belt associated with compression and nappe stacking in the External Hellenides. Simultaneous syn-orogenic extension, low- to high-temperature metamorphism and magmatism in the Internal Hellenides (Olympos-Ossa, Cyclades and Serbo- Macedonian/Rhodope metamorphic province) and finale exhumation of the lower most Rhodope Pangaion unit in the form of a metamorphic core complex, now regarded as part of the Pelagonian nappe. (D6). Neogene-Quaternary: active Hellenic subduction zone and compression associated contemporaneously with extension and rapid exhumation during the Early-Middle Miocene of the external Hellenides Oligocene-Miocene HP/LT belt as a series of tectonic windows in the External Hellenides in Peloponnesus and Crete island. Finally, high-angle normal and strike-slip faults some of them are related to intramontagne basins formation and/or recent neo-tectonic activity. h. In summary, the structure of the Hellenides nappes stack and the related movements. Abbreviations as in Fig. 3.

J Geol Geosci 42 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis the emplacement of the Pelagonian nappe on the External and Ionian zones) associated with new subduction processes Hellenides Gavrovo carbonate platform, were again taken and the formation of the External Oligocene-Miocene high- place with simultaneous extension at the structurally internal pressure belt, visible in Peloponnesus and Crete island. In higher Hellenides’ nappes and finally exhumation of the Peloponnesus and Crete island Oligocene-Miocene nappe Sidironero and Kerdylia units in the East [214-215,4,24- stacking was progressively followed again by new Early- 26,163,217,54,30,15,22]. At the same time, new magmatic Middle Miocene bulk coaxial extension and nappes denudation activity took place in the whole Serbo-Macedonia/Rhodope along normal detachments faults, causing a series of Miocene province (e.g. Vrondou and Xanthi granites, volcanic tectonic windows and metamorphic core complexes, where rocks in between the turbidites deposits of the Thrace basin the Oligocene-Miocene high-pressure rocks of the External etc [308,227,225,216,148,24,202,232,6-8,93]. Eocene Hellenides, represented by the Plattenkalk series (Ionian syn-extensional high-temperature metamorphism and zone) and Phyllite-Quarzite series (of unknown origin), were migmatization processes have been also described in the middle exhumed from under the whole Hellenides nappes stack and Rhodope Sidironero unit, ascribed to mantel delamination under an isothermal decompression P-T metamorphic path processes [78,214-215,202,232,30,15,22]. (e.g. Taygetos window, Leyka Ori window, Psiloritis window) [71-74,111-112,313-315,287,76,310,298-299]. During the Oligocene-Miocene (D5 event), when Europe had already been collided with the Apulia`s fragments, including During the Neogene, an extensional regime dominates in the the Pelagonian, extension under brittle conditions took place entire Hellenides belt, associated with high-angle normal and in the structurally higher Hellenides nappes levels, while oblique strike-slip faults (D6 event), in some cases expressed ductile conditions dominated in the structurally deeper levels, by transpressional or transtenssional tectonics [212,2156-8,93], associated with low- to high-temperature metamorphism dismembering all pre-Neogene tectonic units and structures. and new magmatic activity and migmatization, respectively. In the present time, the convergence still migrates towards the So that brittle conditions dominate in the upper parts of the SW, being directed in the active Hellenic subduction zone, Pelagonian nappes pile while ductile conditions are recognized where the African plate is subducting under the Hellenides in the lower Rhodope Pangaion unit, the earlier formed towards the NE, forming the active Hellenic subduction zone during the Paleocene-Eocene high pressure metamorphic and volcanic arc of the Aegean sea. belt and the Cyclades or else in the lower-most parts of the The described here orogenic outward, Tertiary W- to SW-ward Pelagonian nappe [67-69,115,4,5-8,93,58]. The former migration of the dynamic peer compression vs extension, overthickened lithospheric crust collapsed along normal related respectively, to nappes stacking vs crustal uplift detachment faults, which show a main top-to-the-SW sense and mantel delamination or the contemporaneous action of of movement (e.g. Olympos detachment, Strymon-valley compressional and extensional tectonics in several parts of the detachment) [67-69,115,4,227,115,24-26,163,225] or top-to- Hellenic orogenic belt (e.g. External and Internal Hellenides) the-NE sense of movement (e.g Cyclades detachment faults) could be well explained by a retreating subduction zone and [119,309,206,10,142]. This collapse caused the formation roll-back of the subducted Pindos-Cyclades lithospheric slab of several tectonic windows and/or metamorphic core under the Pelagonian and the other Internal Hellenides nappes complexes, where the upper structurally series of the Apulia stack [227,266,3,9,231,202,316,5,58,206,16,22]. plate were exhumed from under the Internal Hellenides nappes stack (e.g. Olympos, Rizomata and Paikon windows, Pangaion Conclusion and Cyclades metamorphic core complexes) [119,225- • The Alpine structural evolution of the Hellenides starts 227,310,218,5-8,58,93,174,311-312,125]. In the Olympos- with the continental rifting of the Pangaea Super- Ossa area, the exhumation was very rapid and took place under continent during the Permo-Triassic and the progressive an isothermal decompression path, while in the Rhodope and opening of the Neotethyan Meliata-Axios/Vardar ocean Cyclades provinces the exhumation followed a decompression realm. Formation of new oceanic crust started in the path with an initially increasing temperature gradient [117- Early-Middle Triassic. 119,51-52,67-69,5,58,227,225,78,125]. According to our recent works, a constrictional type deformation (i.e. NW-SE • Alpine deformation and metamorphism are recorded compression along the Y-axis of the strain ellipsoid, Y<1) in a multiphase deformational setting from the characterizes the described Tertiary tectonic activity in the Middle-Jurassic to present day. Compression, nappe Internal Hellenides’ nappes [211-212,214-216,68-69,6- stacking and high-pressure metamorphism alternated 8,93,174]. progressively through time with extension, orogenic collapse and low- to high-temperature metamorphism Simultaneously, with the Oligocene-Miocene extension, with migmatites formation in places. Extension was nappes collapse and exhumation processes in the Olympos- leading to uplift and exhumation of deep crustal levels Ossa/Cyclades province and the Rhodope province (Internal as tectonic windows or metamorphic core complexes Hellenides), again new compression and SW-wards verging (e.g. Olympos-Ossa window, Cyclades and Rhodope nappe stacking developed at the External Hellenides (Gavrovo

J Geol Geosci 43 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Pangaion metamorphic core complexes, Cretan and during the Eocene-Oligocene. Peloponnesus windows). An S- to SW-ward migration • The Pelagonian nappe and the overlain ophiolites nappes of the dynamic peer compression vs extension is clearly together with the Paleocene-Eocene high-pressure belt recognized during the Tertiary in the Hellenides. In any which formed during the Cyclades- Pindos small ocean case extension and crustal uplift follow compression basin subduction under the Pelagonian, were emplaced and nappe stacking or they take place simultaneously on the External Hellenides Gavrovo carbonate platform but in different places of the orogen. (Apulia plate) during the Eocene-Oligocene. The latter • The ophiolite belts, including the Mid-Late Jurassic exhumed subsequently during the Oligocene-Miocene ophiolitic mélanges, in the Hellenides are considered as the Olympos-Ossa tectonic window and the Cyclades as far travelled nappes, originated from a single source metamorphic core complex. ocean and this was the Neotethyan Axios/Vardar ocean • A retreating subduction zone and roll back of the basin. Nappe thrusting and ophiolites overriding was subducted Pindos-Cyclades lithospheric slab under the started during the Early-Middle Jurassic related to the Pelagonian related also to mantel delamination could evolution of an intra-oceanic subduction in the Meliata- explain well the Tertiary S- to SW-ward migration of the Axios/Vardar ocean. The upper limit of the ophiolite extensional tectonics and crustal uplift, progressively emplacement on the Apulian (Pelagonia) and European following the same direction`s migration of the Tertiary (Serbo-Macedonian) continental margins respectively, compressional tectonics and nappes stacking. is the Oxfordian/Kimmeridgian. The Axios/Vardar ocean closed finally during the Late Cretaceous- Acknowledgment Paleocene, subducted under the European continental Dedicated to my students of the School of Geology of the margin. University of Thessaloniki GR, as well as to my teachers, • The Axios/Vardar zone is allochthonous and the Axios/ friends and colleagues with whom I collaborated a long time Vardar suture zone is traced at depth in between the of about 50 years. I can` t forget the nice field work days and Rhodopes nappes. The Internal Hellenides Serbo- the endless discussions about the geological problems and Macedonian/Rhodope thrust stack is rooted along the orogenic processes. northeastern boundary of the Rhodope massif with the References Strandja/Sredna Gora massifs (European plate). Nappe 1. Jacobshagen V, Dürr F, Kockel K, Kopp KO, Kowalczyk G et al. thrusting migrated during the Tertiary S- to SW-ward, (1978) Structure and geodynamic evolution of the Aegean region becoming progressively younger to the W-SW, until the in: Cloos H, Roeder D, Schmidt K, (eds) IUGG S. (Ed) Alps External Hellenides thrust sheets and the today active Apennines, Hellenides 537–564. [View Article] Hellenic subduction zone. 2. Mountrakis DM (1986) The Pelagonian Zone in Greece: A • The lower-most Pangaion Rhodope unit should be the Polyphase-Deformed Fragment of the Cimmerian Continent eastern more marginal part of the Pelagonian fragment, and Its Role in the Geotectonic Evolution of the Eastern Mediterranean. J Geol 94: 335–347. [View Article] belonging to the Apulia plate, which following the Late Cretaceous/Paleocene closure of the Axios/Vardar 3. Ricou LE, Burg JP, Godfriaux I, Ivanov Z (1998) Rhodope and ocean remnants was underthrusted during the Tertiary Vardar: The metamorphic and the olistostromic paired belts related to the Cretaceous subduction under Europe. Geodin Acta (Paleocene-Eocene) below the European continental 11: 285–309. [View Article] margin, including the Serbo-Macedonian basement and its Mesozoic sedimentary cover (Vertiskos and 4. Kilias A, Tranos MD, Orozco M, Alonsochaves FM, Soto JI (2002) Extensional collapse of the Hellenides: A review. Rev la Kimi units). Slices of the subducted northeastward Soc Geol Espana 15: 129–139. [View Article] Axios/Vardar ocean remnants are tectonically included 5. Kilias A, Frisch W, Avgerinas A, Dunkl I, Falalakis G et al. (2010) inbetween the Sidironero middle Rhodope unit Alpine architecture and kinematics of deformation of the northern during the Paleocene-Eocene continental collision of Pelagonian nappe pile in the Hellenides. Austrian J Earth Sci the Pelagonian and Europe. Finally, the lower-most 103: 4–28. [View Article] Pangaion Rhodope unit exhumed as a metamorphic 6. Katrivanos E, Kilias A, Mountrakis D (2013) Kinematics of core complex below the Serbo-Macedonian/Rhodope deformation and structural evolution of the Paikon Massif nappe stack during the Oligocene-Miocene extensional (, Greece): A Pelagonian tectonic window? tectonics of the Internal Hellenides and the broader Neues Jahrb für Geol und Paläontologie – Abhandlungen 269: Aegean region. Respectively, the Serbo-Macedonian/ 149–171. [View Article] Rhodope nappes exhumed progressively, initially with 7. Kilias A, Falalakis G, Sfeikos A, Papadimitriou E, Vamvaka A the exhumation of the Vertiskos and Kimi units during et al. (2013) The Thrace basin in the Rhodope province of NE the Late Cretaceous to Paleocene-Eocene, followed by Greece - A tertiary supradetachment basin and its geodynamic implications. Tectonophysics 595: 90–105. [View Article] the exhumation of the Sidironero and Kerdylia units

J Geol Geosci 44 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

8. Koroneos A, Kilias A, Avgerinas A (2013) Hercynian plutonic 23. Frisch W (1981) Plate motions in the Alpine region and their rocks of Voras Mountain, Macedonia, Northern Greece: their correlation to the opening of the . Geol Rundschau structure, petrogenesis, and tectonic significance. Int Geol Rev 70: 402–411. [View Article] 55: 994–1016. [View Article] 24. Christofides G, Koroneos A, Soldatos T, Eleftheriadis G, Kilias 9. Jolivet L, Rimmele G, Oberhansli R, Goffe B, Candan O (2004) A (2001) Eocene magmatism ( and Elatia plutons) in Correlation of syn-orogenic tectonic and metamorphic events in the the Internal Hellenides and implications for Eocene-Miocene Cyclades, the Lycian nappes and the Menderes massif. Geodynamic geological evolution of the Rhodope massif (Northern Greece). implications. Bull la Soc Geol Fr 175: 217–238. [View Article] Acta Vulcanol 13: 73–89. [View Article] 10. Jolivet L, Brun JP (2010) Cenozoic geodynamic evolution of the 25. Kilias A (2001) Late orogenic extension in Hellenides (in Greek with Aegean. Int J Earth Sci 99: 109–138. [View Article] English abstract). Bull Soc Geol Greece 34: 149–156. [View Article] 11. Schmid SM, Bernoulli D, Fügenschuh B, Matenco L, Schefer S 26. Kilias A, Tranos M, Mountrakis D, Shallo M, Marto A et al. (2001) et al. (2008) The Alpine-Carpathian-Dinaridic orogenic system: Geometry and kinematics of deformation in the Albanian orogenic Correlation and evolution of tectonic units. Swiss J Geosci 101: belt during the Tertiary. J Geodyn 31: 169–187. [View Article] 139–183. [View Article] 27. Gawlick HJ, Missoni S, Sudar NM, Suzuki H, Meres S et al. 12. Schmid S, Fügenschuh B, Kounov A, Mațenco L, Nievergelt P (2018) The Jurassic Hallstatt Melange of the Inner Dinarides et al. (2020) Tectonic units of the Alpine collision zone between (SW Serbia): implications for Triassic-Jurassic geodynamic and Eastern Alps and western Turkey. Gondwana Research 78: 308– paleogeographic reconstructions of the Western Tethyan realm. N 374. [View Article] Jb Geol Palaeont Abh 288: 1-47. [View Article] 13. Gawlick HJ, Frisch W, Hoxha L, Dumitrica P, Krystyn L et al. (2008) 28. Ghon G, Gawlick HJ, Missoni S, Djeric N, Kilias A (2018) Age Mirdita Zone ophiolites and associated sediments in Albania reveal and microfacies of a carbonate-clastic radiolaritic basin fill above Neotethys Ocean origin. Int J Earth Sci 97: 865–881. [View Article] the Koziakas Mélange (Hellenides, Greece). XXI Inter. Congress of the CBGA, (abstract), Salzburg, Austria. [View Article] 14. Saccani E, Bortolotti V, Marroni M, Pandolfi L, Photiades A et al. (2008) The Jurassic association of backarc basin 29. Schlagintweit F, Gawlick HJ, Missoni S, Hoxha L, Lein R et al. ophiolites and calc-alkaline volcanics in the Guevgueli Complex (2008) The eroded Late Jurassic Kurbnesh carbonate platform (NorthernGreece): Implication for the evolution of the Vardar in the Mirdita Ophiolite Zone of Albania and its bearing on the Zone. Ofioliti 33: 209–227. [View Article] Jurassic orogeny of the Neotethys realm. Swiss J Geosciences 101: 125-138. [View Article] 15. Jahn-Awe S, Froitzheim N, Nagel TJ, Frei D, Georgiev N et al. (2010) Structural and geochronological evidence for Paleogene 30. Georgiev N, Pleuger J, Froitzheim N, Sarov S, Jahn-Awe S (2010) thrusting in the western Rhodopes, SW Bulgaria: Elements for Separate Eocene–Oligocene and Miocene stages of extension and a new tectonic model of the Rhodope Metamorphic Province. core complex formation in the Western Rhodopes, Mesta Basin, Tectonics 29 : 1–30. [View Article] and Pirin Mountains (Bulgaria). Tectonophysics 487: 59–84. [View Article] 16. Burg JP (2012) Rhodope: From mesozoic convergence to cenozoic extension. Review of petro-structural data in the 31. Stampfli GM, Borel GD (2002) A plate tectonic model for the geochronological frame. J Virtual Explor 42. [View Article] Paleozoic and Mesozoic constrained by dynamic plate boundaries and restored synthetic oceanic isochrons. Earth Planet. Sci Lett 17. Robertson AHF (2012) Late Palaeozoic–Cenozoic tectonic 196: 17–33. [View Article] development of Greece and Albania in the context of alternative reconstructions of Tethys in the Eastern Mediterranean region. Int 32. Stampfli GM, Vavassis I, De Bono A, Rosselet F, Matti B et al. (2003) Geol Rev 54: 373–454. [View Article] Remnants of the paleotethys oceanic suture-zone in the western tethyan area. Boll della Soc Geol Italia 2: 1–23. [View Article] 18. Bortolotti V, Chiari M, Marroni M, Pandolfi L, Principi G et al. (2013) Geodynamic evolution of ophiolites from Albania 33. Bonev NG, Stampfli GM (2003) New structural and petrologic and Greece (Dinaric-Hellenic belt): One, two, or more oceanic data on Mesozoic schists in the Rhodope (Bulgaria): Geodynamic basins? Int J Earth Sci 102: 783–811. [View Article] implications. Comptes Rendus - Geosci 335: 691–699. [View Article] 19. Robertson AHF, Trivić B, Derić N, Bucur II (2013) Tectonic 34. Shallo M, Dilek Y (2003) Development of the ideas on the origin development of the Vardar ocean and its margins: Evidence from of Albanian ophiolites. Geol Soc Am Spec Publ 373: 351–363. the Republic of Macedonia and Greek Macedonia. Tectonophysics [View Article] 595: 25–54. [View Article] 35. Sharp IR, Robertson HF (2006) Tectonic-sedimentary evolution 20. Papanikolaou D (2009) Timing of tectonic emplacement of the of the western margin of the Mesozoic Vardar Ocean: evidence ophiolites and terrane paleogeography in the Hellenides. Lithos from the Pelagonian and Almopias zones, northern Greece. Geol 108: 262–280. [View Article] Soc London Spec Publ 260: 373–412. [View Article] 21. Papanikolaou D (2013) Tectonostratigraphic models of the Alpine 36. Danelian T, Robertson AHF, Dimitriadis S (1996) Age and terranes and subduction history of the Hellenides. Tectonophysics significance of radiolarian sediments within basic extrusives of 595: 1–24. [View Article] the marginal basin Guevgueli Ophiolite (northern Greece). Geol Mag 133: 127–136. [View Article] 22. Froitzheim N, Jahn-Awe S, Frei D, Wainwright AN, Maas R (2014) Age and composition of meta-ophiolite from the Rhodope 37. Rassios AHE, Moores EM (2006) Heterogeneous mantle Middle Allochthon (Satovcha, Bulgaria): A test for the maximum- complex, crustal processes, and obduction kinematics in a unified allochthony hypothesis of the Hellenides. Tectonics 33: 1477– Pindos-Vourinos ophiolitic slab (northern Greece). Tecton Dev 1500. [View Article] East Mediterr Reg 260: 237–266. [View Article]

J Geol Geosci 45 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

38. Dilek Y, Furnes H, Shallo M (2007) Suprasubduction ophiolite evolution of an extensional gneiss dome - The Kesebir-Kardamos formation along the periphery of Mesozoic Gondwana. dome, eastern Rhodope (Bulgaria-Greece). Int J Earth Sci 95: Gondwana Research 11: 453–475. [View Article] 318–340. [View Article] 39. Dilek Y, Shallo M, Furnes H (2008) Geochemistry of the Jurassic 55. Bonev N, Marchev P, Moritz R, Collings D (2015) Jurassic Midita Ophiolite (Albania) and the MORB to SSZ evolution of a subduction zone tectonics of the Rhodope Massif in the Thrace marginal basin oceanic crust. Lithos 100: 174–209. [View Article] region (NE Greece) as revealed by new U–Pb and 40Ar/39Ar geochronology of the ophiolite and high-grade basement 40. Ghikas D, Dilek Y, Rassios EA (2009) Structure and tectonics rocks. Gondwana Research 27: 760–775. [View Article] of subophiolitic melanges in the western Hellenides (Greece): Implications for ophiolite emplacement tectonics. Int Geology 56. Bonev N, Moritz R, Borisova M, Filipov P (2018) Therma-Volvi- Review 52: 423-453. [View Article] Gomati complex of the Serbo-Macedonian Massif, Northern Greece: A Middle Triassic continental margin ophiolite of 41. Rassios AE, Dilek Y (2009) Rotational deformation in the Jurassic Neotethyan origin. J Geological Society. [View Article] Mesohellenic ophiolites, Greece, and its tectonic significance. Lithos 108: 207–223. [View Article] 57. Bonev N, Filipov P (2018) From an ocean floor wrench zone origin to transpressional tectonic emplacement of the Sithonia 42. Petrík I, Janák M, Froitzheim N, Georgiev N, Yoshida K et al. ophiolite, eastern Vardar Suture Zone, northern Greece. Int J (2016) Triassic to Early Jurassic (c. 200 Ma) UHP metamorphism Earth Sci 107: 1689–1711. [View Article] in the Central Rhodopes: evidence from U–Pb–Th dating of monazite in diamondbearing gneiss from Chepelare (Bulgaria). J 58. Vamvaka A, Spiegel C, Frisch W, Danišík M, Kilias A (2010) Metamorph Geol 34: 265–291. [View Article] Fission track data from the Mesohellenic Trough and the Pelagonian zone in NW Greece: Cenozoic tectonics and 43. Miladinova I, Froitzheim N, Nagel JT, Janák M, Georgiev N et al. (2018) Late Cretaceous eclogite in the Eastern Rhodopes exhumation of source areas. Int Geology Rev 52: 223-249. [View (Bulgaria): evidence for subduction under the Sredna Gora Article] magmatic arc. Int J Earth Sci 1-17. [View Article] 59. Katrivanos E, Kilias A, Mountrakis D (2016) Deformation 44. Brunn JH (1956) Contribution à l’étude géologique du Pinde history and correlation of Paikon & Tzena terranes (Axios zone, septentrional et d’ une partie de la Macédoine occidnetale. Ann central Macedonia, Greece). Bulletin of the Geological Society th Géologique Pays Hel l7 : 1–358. [View Article] of Greece, XLVΙII, Proceedings of the 14 Intern. Conference, Thessaloniki. [View Article] 45. Aubouin J (1959) Contribution a l’ étude géologique de la Grèce septentrional : les confins de l’ Epire et de la . Ann Géol 60. Kilias A, Thomaidou E, Katrivanos E, Vamvaka A, Fassoulas des Pays Hellén 10: 1–525. [View Article] Ch et al. (2016) A geological cross-section through northern Greece from Pindos to Rhodope Mountain Ranges: a field guide 46. Zouros N, Mountrakis D (1991) The thrusting of the Pindos zone accross the External and Internal Hellenides. In: (Eds.) Kilias, A. and the relationship between the External geotectonic zones in and Lozios, S., Geological field trips in the Hellenides. J Virtual -eastern Zagori area (NW Greece). Bull Geol Soc Greece Explorer 50: 1. [View Article] 25: 245–262. [View Article] 61. Michail M, Pipera K, Koroneos A, Kilias A, Ntaflos T (2016) New 47. Mountrakis D, Kilias A, Zouros N (1993) Kinematic analysis and Tertiary evolution of the Pindos-Vourinos ophiolites (- perspectives on the origin and emplacement of the Late Jurassic , Greece). Bull Geol Soc Greece 28: 111–124. Fanos granite, associated with an intra-oceanic subduction within [View Article] the Neotethyan Axios-Vardar Ocean. Int J Earth Sci 105: 1965– 1983. [View Article] 48. Zouros N (1993) Study of the tectonic structures connected with the Pindos nappe in Epirus (NW Greece). Univ of Thessaloniki, 62. Ferrière J, Chanier F, Ditbanjong P (2012) The Hellenic Greece 630. [View Article] ophiolites: eastward or westward obduction of the Maliac Ocean, a discussion. Int J Earth Sci 101: 1559–1580. [View Article] 49. Mercier J, Vergely P (1984) Geological map of Greece, 1:50.000, Edhessa sheet. Institute of Geology and Mineral Exploration, 63. Schenker FL, Fellin MG, Burg JP (2015) Polyphase evolution of Athens. [View Article] Pelagonia (northern Greece) revealed by geological and fission- track data. Solid Earth 6: 285–302. [View Article] 50. Vergely P (1984) Tectoniques des ophiolites dans les Hellénides Internes déformation, métamorphisme et phénomènes 64. Altherr R, Schliestedt M, Okrusch M, Seidel E, Kreuzer H et al. sédimentaires. Conséquences sur l’ évolution des région (1979) Geochronology of high- pressure rocks on Sifnos (Greece, Téthysiennes Occidentales. PhD Thesis, University Paris-Sud, Cyclades). Contrib Miner Petrol 70: 245-255. [View Article] Orsay, 1-560. [View Article] 65. Wijbrans JR, McDougall I (1986) 40Ar/39Ar dating of white 51. Schermer ER (1990) Mechanisms of blueschist creation and micas from an Alpine high-pressure metamorphic belt on Naxos preservation in an A-type subduction zone, Mount Olympos (Greece): the resetting of the argon isotopic system. Contrib to region, Greece. Geology 18: 1130-1133. [View Article] Mineral Petrol 93: 187–194. [View Article] 52. Schermer ER, Lux DR, Burchfiel BC (1990) Temperature-time 66. Okrusch M, Broecker M (1990) Eclogites associated with history of subducted continental crust, Mount Olympos Region, highgrade blueschists in the Cycladic archipelago, Greece: a Greece. Tectonics 9: 1165–1195. [View Article] review. European J Mineralogy 2: 451-478. [View Article] 53. Schermer ER (1993) Geometry and kinematics of continental 67. Kilias A (1991) Transpressive tektonik in den zentralen Helleniden. basement deformation during the Alpine orogeny, Mt. Olympos Aenderung der translations pfade durch die transpression (Nord- region, Greece. J Struct Geol 15: 571–591. [View Article] zentral Griechenland). Neues Jahrb für Geol und Paläentologie 54. Bonev N, Burg JP, Ivanov Z (2006) Mesozoic-Tertiary structural Monatshefte 20: 291–306. [View Article]

J Geol Geosci 46 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

68. Kilias A, Fassoulas C, Priniotakis M, Frisch W, Sfeikos A (1991) pressure metamorphic events by U-Pb SHRIMP geochronology Deformation and HP/LT metamorphic condition at the tectonic and REE geochemistry of zircon: The Rhodope zone of Northern window of Kranea (W. Thessaly, N. Greece). Z Dtsch Geol Ges Greece. Contrib. to Mineral. Petrol 150: 608–630. [View Article] 142: 87–96. [View Article] 82. Krenn K, Bauer C, Proyer A, Kloetzli U, Hoinkes G (2010) 69. Sfeikos Α, Böhringer C, Frisch W, Kilias A, Ratschbacher L Tectonometamorphic evolution of the Rhodope orogen. Tectonics (1991) Kinematics of the Pelagonian nappes in the Kranea area, 29. [View Article] N. Thessaly (Greece). Bull Geol Soc Greece 25: 101–115. [View 83. staszewski K, Kounov A, Schmid MS, Schaltegger U, Krenn Article] E (2010) Evolution of the Adria-Europe plate boundary in the 70. Broecker M, Kreuzer H, Matthews A, Okrusch M (1993) northern Dinarides: From continent-continent collision to back- 40Ar/39Ar and oxygen isotope studies of polymetamorphism from arc extension. Tectonics 29: TC6017. [View Article] Island, Cycladic blueschist belt, Greece. J Metamorphic 84. Schmidt S, Nagel TJ, Froitzheim N (2010) A new occurrence Geology 11: 223-240. [View Article] of microdiamond-bearing metamorphic rocks, SW Rhodopes, Greece. Eur J Mineral 22: 189–198. [View Article] 71. Seidel E, Kreuzer H, Harre W (1982) A Late Oligocene/Early Miocene high pressure belt in the external Hellenides. Geol Jahrb 85. Nagel TJ, Schmidt S, Janák M, Froitzheim N, Jahn-Awe S (2011) 23: 165–206. [View Article] The exposed base of a collapsing wedge: The Nestos Shear Zone (Rhodope Metamorphic Province, Greece). Tectonics 30: 1-17. 72. Fassoulas C, Kilias A, Mountrakis D (1994) Postnappe stacking [View Article] extension and exhumation of high-pressure/low-temperature rocks in the island of Crete, Greece. Tectonics 13 : 127–138. 86. Kirchenbaur M, Munker C, Schuth S, Garbe-schonberg D, Marchev [View Article] P (2012) Tectonomagmatic constraints on the sources of Eastern Mediterranean K-rich lavas. J Petrol 53: 27–65. [View Article] 73. Kilias A, Fassoulas C, Mountrakis D (1994) Tertiary extension of continental crust and uplift of Psiloritis metamorphic core 87. Collings D, Savv I, Maneiro K, Baxter E, Harvey J et al. (2016) complex in the central part of the Hellenic Arc (Crete, Greece). Late Cretaceous UHP metmorphism recorded in kyanite–garnet Geol Rundschau 83: 417–430. [View Article] schists from the Central , Bulgaria. Lithos 246: 165–181. [View Article] 74. Jolivet L, Goffé B, Monié P, Truffert-Luxey C, Patriat M (1994) Miocene detachment in Crete and exhumation P-T-t paths of 88. Ferrière J, Reynaud JY, Migiros G, Proust JN, Bonneau M high-pressure metamorphic rocks. Tectonics 15: 1129–1153. et al. (1998) Initiation d ’un bassin transporté: l’ exemple du [View Article] “sillon meso-hellénique” au Tertiaire (Grèce). Comptés Rendus l’Académie Sci Ser IIa Sci la Terre des Planètes 326: 567–574. 75. Stöckhert B, Wachmann M, Küster M, Bimmermann S (1999) [View Article] Low effective viscosity during high pressure metamorphism due to dissolution precipitation creep: The record of HP-LT 89. Zelilidis A, Piper DJW, Kontopoulos N (2002) Sedimentation and metamorphic carbonates and siliciclastic rocks from Crete. basin evolution of the Oligocene–Miocene Mesohellenic basin, Tectonophysics 303: 299–319. [View Article] Greece: American Association of Petroleum Geologists Bulletin 86: 161–182. [View Article] 76. Thomson SN, Stöckhert B, Brix MR (1999) Miocene high- pressure metamorphic rocks of Crete, Greece: Rapid exhumation 90. Mountrakis D, Tranos M, Papazachos C, Thomaidou E, by buoyant escape. In U. Ring, M. T. Brandon, G. S., Lister, & Karagianni E et al. (2006) Neotectonic and seismological data S. D. Willet (Eds.), Exhumation Processes: Normal Faulting, concerning major active faults, and the stress regimes of Northern Ductile Flow and Erosion. Geol Soc London Spec 87–107. [View Greece. Geol Soc London Spec Publ 260: 649–670. [View Article] Article] 91. Vamvaka A, Kilias A, Mountrakis D, Papaoikonomou I (2006) 77. Wawrzenitz N, Mposkos E (1997) First evidence for Lower Geometry and structural evolution of the Mesohellenic Trough Cretaceous HP/HT-Metamorphism in the Eastern Rhodope, (Greece): a new approach. Geol Soc London 260: 521-538. [View Article] Region, North-East Greece. Eur J Mineral 9: 659– 664. [View Article] 92. Maravelis A, Konstantopoulos P, Pantopoulos G, Zelilidis A (2007) North Aegean sedimentary basin during te Late Eocene 78. Liati AL, Gebauer DG (1999) Constraining the prograde and to Early Oligocene based on sedimentological studies on Limnos retrograde P-T-t path of Eocene HP rocks by SHRIMP dating of island (NE Greece). Geol Carpathica 58: 455-464. [View Article] different zircon domains: Inferred rates of heating, burial, cooling and exhumation for central Rhodope, northern Greece. Contrib to 93. Kostaki G, Kilias A, Gawlick HJ, Schlagintweit F (2013) Mineral Petrol 135: 340–354. [View Article] Kimmeridgian-Tithonian shallow-water platform clasts from mass flows on top of the Vardar/Axios ophiolites. Bull Geol Soc 79. Mposkos ED, Kostopoulos DK (2001) Diamond, former coesite Greece 1–10. [View Article] and supersilicic garnet in metasedimentary rocks from the Greek Rhodope: A new ultrahigh-pressure metamorphic province 94. Kilias A, Vamvaka A, Falalakis G, Sfeikos A, Papadimitriou E et established. Earth Planet. Sci Lett 192: 497–506. [View Article] al. (2015) The Mesohellenic Trough and the Paleogene Thrace Basin on the Rhodope Massif, their Structural Evolution and 80. Mposkos E, Kostopoulos D, Krohe A (2001) Low-P/High-T Geotectonic Significance in the Hellenides. J Geol Geosci 4: prealpine metamorphism and medium-P alpine overprint of the 1–17. [View Article] Pelagonian zone documented in high-alumina metapelites from the Vernon massif, Western Macedonia, Northern Greece. Bul 95. Kockel F, Mollat H, Walther HW (1977) Erläuterungen Geological Society of Greece 34: 949-958. [View Article] zur Geologischen Karte der Chalkidhiki und angrenzender Gebiete 1:100.000 (Nord-Griechenland). Bundesanstalt fuer 81. Liati A (2005) Identification of repeated Alpine (ultra) high- Geowissenschaften und Rohstoffe, Hannover 119. [View Article]

J Geol Geosci 47 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

96. Psilovikos A (1977) Paleogeographic evolution of the Mygdonia 112. Theye T, Seidel E, Vidal O (1992) Carpholite, sudoite and basin and lake (Lagada-Volvi). PHD-Thesis, University Thessaloniki, chloritoid in low-grade high-pressure metapelites from Crete (in Greek with english abstract). 1-156. [View Article] and the Peloponnese. Eur. J. Mineral 4: 487-507. [View Aricle] 97. Pavlides SB, Mountrakis DM (1987) Extensional tectonics of 113. Godfriaux I (1968) Étude géologique de la region de l’Olympe northwestern Macedonia, Greece, since the late Miocene. J Struct (Grèce). Annales Géologiques des Pays Helléniques 19: 1-281. Geol 9: 385–392. [View Article] [View Aricle] 98. Pavlides S, Kilias A (1987) Neotectonic and active faults along the 114. Godfriaux I, Ricou LE (1991) The Paikon, a tectonic window Serbomacedonian zone (, N. Greece). Ann Tectonicae within the Internal Hellenides, Macedonia, Greece. Comptes 1: 97–104. [View Article] Rendus - Acad. des Sci. Ser., II 313: 1479-1484. [View Aricle] 99. Koufos G, Pavlides S (1988) Correlation between the continental 115. Kilias A (1995) Emplacement of the blueschists unit in eastern deposits of the Lower Axios Valley and Ptolemais Basin. Bull Soc Thessaly and exhumation of Olympos-Ossa carbonate dome as a Geol Greece 20: 9-19. [View Article] result of Tertiary extension (central Greece). Miner. Wealth 96: 100. Syrides G (1990) Lithostratigraphical, Biostratigraphical and 7-22. [View Aricle] Paleographical study of the Neogene-Quaternary sedimentary 116. Lips AL, White WSH, Wijbrans JR (1998) 40Ar/39Ar laser formations of the Chalkidiki Peninsula. PhD University probe direct dating of discrete deformational events: A Thessaloniki (in Greek with english abstract) 1-241. [View continuous record of early Alpine tectonics in the Pelagonian Article] Zone, NW Aegean area, Greece, Tectonophysics 298: 133-153. 101. Ioakim Ch, Rondoyianni Th, Mettos A (2005) The Miocene [View Aricle] basins of Greece from a paleoclimatic prospective. Revue de 117. Altherr R, Kreuzer H, Wendt I, Lenz H, Wagner GA, et al. (1982) Paleobiologie 24: 735-748. [View Aricle] A late Oligocene/early Miocene high temperature belt in the 102. Aubouin J, Blanchet R, Cadet JP, Celet P, Charvet J, et al. Attico-Cycladic crystalline complex (SE Pelagonian, Greece). (1970) Essai sur la géologie des Dinarides. Bulletin de la Société Geol. Jahrb E23: 97-164. [View Aricle] Géologique de 12: 1060-1095. [View Aricle] 118. Reinecke T, Altherr R, Hartung B, Hatzipanagiotou K, Kreuzer 103. Bernoulli D, Laubscher H (1972) The palinspastic problem of H, et al. (1982) Remnants of Late Cretaceous high temperature the Hellenides. Eclogae geologicae Helvetiae 65:107-118. [View belt on the island of Anafi (Cyclades, Greece), Neus Jahrb. Aricle] Mineral. Abh. 145: 157-182. [View Aricle] 104. Apanikolaou D (1997) The tectonostratigraphic terranes of the 119. Lister GS, Banga G, Feenstra A (1984) Metamorphic core Hellenides. An. Geol. des Pays Helleniques 37: 33-48. [View complexes of cordilleran type in the Cyclades, Aegean Aricle] Sea,Greece, Geology 12: 221-225. [View Aricle] 105. Zoumpouli Ε, Pomoni-Papaioannou F, Zelilidis A (2010) 120. Keay S, Lister G, Buick I (2001) The timing of partial melting, Studying in the Paxos Zone the carbonate depositional Barrovian metamorphism and granite intrusion in the Naxos environment changes during upper Cretaceous, in Sami area of metamorphic core complex, Cyclades, Aegean Sea, Greece. Kefallinia Island, Greece. Βull. Geol. Soc. Greece, XLIII 2: 793- Tectonophysics 342: 275-312. [View Aricle] 801. [View Aricle] 121. Grasemann B, Petrakakis K (2007) Evolution of the Serifos 106. Zoumpouli Ε, Pomoni-Papaioannou F, Zelilidis A, Iliopoulos metamorphic core complex. Journal of the Virtual Explorer 27. G (2013) Biostratigraphical and sedimentological study of an [View Aricle] Upper Cretaceous succession in the Sami area (Central Area of Kefallinia, W. Greece). Bull. Geol. Soc. Greece, ΧLVII 2: 506- 122. Iglseder C, Grasemann B, Rice AHN, Petrakakis K, Schneider 518. [View Aricle] DA (2011) Miocene south directed low-angle normal fault evolution on Kea Island (West Cycladic Detachment System, 107. Zoumpouli E (2016) Carbonate Sedimentation in Kephalonia Greece). Tectonics 30: TC4013. [View Aricle] Island, Zone, during Mesozoic. PhD Thesis, University Patras 1-227. [View Aricle] 123. Roche V, Laurent V, Luca Cardello G, Jolivet L, Scaillet S (2016) Anatomy of the Cycladic Blueschist Unit on Sifnos 108. Bonneau M (1984) Correlation of the Hellenides Nappes in the Island (Cyclades, Greece). Journal of Geodynamics 97: 62-87. south-east Aegean and their tectonic reconstruction. Geol. Soc. [View Aricle] London, Spec. Publ. 517-527. [View Aricle] 124. Ring, U, Glodny J, Peillod A, Skelton A (2018) The timing of 109. Skourtsos M, Lekkas E (2010) Extensional tectonics in Mt hightemperature conditions and ductile shearing in the footwall Parnon (Peloponnesus, Greece). Int. J. Earth Sci. (Geol. of the Naxos extensional fault system, Aegean Sea, Greece. Rundsch.). [View Aricle] Tectonophysics. [View Aricle] 110. Seybold L, Trepmann AC, Janots E (2019) A ductile extensional 125. Linnros H, Hansman R, Ring U (2019) The 3D geometry of shear zone at the contact area between HP-LT metamorphic units the Naxos detachment fault and the threedimensional tectonic in the Talea Ori, central Crete, Greece: deformation during early architecture of the Naxos metamorphic core complex, Aegean stages of exhumation from peak metamorphic conditions. Int. J. Sea, Greece. Intern. Journal of Earth Sciences 198: 287-300. Earth Sciences 108: 213-227. [View Articel]. [View Aricle] 111. Theye T, Seidel E (1991) Petrology of low-grade high-pressure 126. Engel M, Reischmann T (1998) Single zircon geochronology of metapelites from the External Hellenides (Crete, Peloponnese): orthogneisses from , Greece. Bull. Geol. Soc. Greece 32: A case study with attention to sodic minerals. Eur. J. Mineral 3: 91-99. [View Aricle] 343-366. [View Aricle]

J Geol Geosci 48 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

127. Reischmann T (1998) Pre-Alpine origin of tectonic units from the Late Cretaceous until the Miocene to recent above the retreating the metamorphic complex of Naxos, Greece, identified by single Hellenic subduction zone. Tectonics 22: 1022. [View Aricle] zircon Pb/Pb dating. Bulletin of the ‎Geological Society of Greece 141. Ring U, Thomson S, Broecker NM (2003) Fast extension but 32: 101-111. [View Aricle] little exhumation: the Vari detachment in the Cyclades, Greece. 128. Gessner K, Piazolo S, Güngör T, Ring U, Kröner A, et al. (2001) Geol. Mag., 140: 245-252. [View Aricle] Tectonic significance of deformation patterns in granitoid rocks 142. Jolivet L, Lecomte E, Huet B, Denèle Y, Lacombe O (2010) of the Menderes nappes, anatolide belt, Southwest Turkey. International Journal of Earth Sciences 89: 766-780. [View The North Cycladic Detachment System. Earth and Planetary Aricle] Science Letters 289: 87-104. [View Aricle] 129. Ring U, Layer PW, Reischmann T (2001) Miocene high-pressure 143. Sengör AMC, Yılmaz Y, Sungurly O (1984) Tectonics of the metamorphism in the Cyclades and Crete, Aegean Sea, Greece: Mediterranean Cimmerides: Nature and evolution of the western termination of Paleo-Tethys: Geol. Soc. London, Spec. Publ., 17: Evidence for large-magnitude displacement on the Cretan 77-112. [View Aricle] detachment. Geology 29: 395-398. [View Aricle] 144. Vavasis I, De Bono A, Stampfli GM, Giorgio D, Valloton A, 130. Oner Baran Z, Dilek Y, Stockli D (2017) Diachronous uplift and et al. (2000) U-Pb and Ar-Ar geochronological data from the cooling history of the Menderes core complex, western Anatolia Pelagonian basement in Evia (Greece): geodynamic implications (Turkey), based on new Zirkon (U-Th)/He ages. Tectonophysics for the evolution of Paleotethys. Schweiz. Mineral. und Petrogr. 181-196. [View Aricle] Mitteilungen 80: 21-43. [View Aricle] 131. Lamont NTh, Searle PM, Waters JD, Roberts MWN, Palin MR, et 145. Hetzel R, Reischmann T (1996) Intrusion age of Pan-African al. (2019) Compressional origin of the Naxos metamorphic core augen gneisses in the southern Menderes Massif and the age of complex, Greece: Structure, petrography, and thermobarometry. cooling after Alpine ductile extensional deformation. Geological GSA Bulletin. [View Aricle] Magazine 133: 565-572. [View Aricle] 132. Hetzel R, Romer Rl, Candan O, Passchier CW (1998) Geology 146. Brunn JH, Argyriadis I, Ricou LE, Poisson A, Marcoux J, of the Bozdag area, central Menderes massif, SW Turkey: Graciansky PC (1976) Eléments majeurs de liaison entre Pan-African basement and Alpine deformation. Geologische Taurides et Hellénides. Bull. Soc. Géol. Fr., XVIII 2: 481-497. Rundschau 87: 394-406. [View Aricle] [View Aricle] 133. Partzsch JH, Oberhansli R, Candan O, Warkus F (1998) The 147. Robertson AHF, Dixon JE, Brown S, Collins A, Morris A, et al. evolution of the central Menderes massif, West Turkey: a (1996) Alternative tectonic models for the Late Palaeozoic-Early complex nappe pile recording 1.0Ga of geological history. Freib. Tertiary development of Tethys in the Eastern Mediterranean region. Forsch., C-471, 166-168. [View Aricle] Geol. Soc. London, Spec. Publ., 105: 239-263. [View Aricle] 134. Ring U, Gessner K, Güngör T, Passchier CW (1999) The 148. Dinter DA (1998) Late Cenozoic extension of the Alpine collisional Menderes Massif of western Turkey and the Cycladic Massif in orogen, northeastern Greece: Origin of the north Aegean Basin. the Aegean do they really correlate? J. Geol. Soc. London 156: Bull. Geol. Soc. Am. 110: 1208-1230. [View Aricle] 3-6. [View Aricle] 149. Papanikolaou D (1987) Tectonic evolution of the Cycladic 135. Bozkurt E, Oberhaensli R (2001) Menderes Massif (western blueschist belt (Aegean Sea, Greece). In: Helgeson, H.C. (Ed.), Turkey): structural metamorphic and magmatic evolution-a Chemical Transport in Metasomatic Processes: NATO ASI synthesis. Int. J. Earth Sci., 89: 679-708. [View Aricle] Series, 429-450. [View Aricle] 136. Altherr R, Siebel W (2002) I-type plutonism in a continental 150. Kilias A (2018) The Hellenides: A complicated, multiphase back-arc setting: Miocene granitoids and monzonites from the deformed Alpine orogenic belt. Compression vs extension, central Aegean Sea, Greece. Contributions to Mineralogy and the dynamic peer for the orogen making. Proccedings of the Petrology 143: 397-415. [View Aricle] 9th International INQUA Meeting on Paleoseismology, Active Tectonics and Archeoseismology (PATA), Possidi, Greece 119- 137. Dilek Y, Altunkaynak S, Oener Z (2009) Syn-extensional 123. [View Aricle] granitoids in the Menderes core complex and the late Cenozoic extensional tectonics of the Aegean province. Geol. Soc. London, 151. Savoyat E, Lalechos N (1972) Geological Map of Greece, scale Special Publication 321: 197-223. [View Aricle] 1:50.000, Kalampaka Sheet. Institute of Geology and Mineral Exploration, Athens. [View Aricle] 138. Hetzel R, Ring U, Akal C, Troesch M (1995) Miocene NNE- directed extensional unroofing in the Menderes massif, western 152. Lekkas E (1988) Geological structure and geodynsmic evolution Turkey. Journal of the Geological Society, London 152: 639- of the Koziakas Mountain (western Thessaly, Greece). PhD 654. [View Aricle] Thesis, University Athens, ( in Greek with English abstract) 1-280. [View Aricle] 139. Kilias A, Mountrakis D, Tranos M, Pavlides S (1996) The prevolcanic metamorphic rocks of Santorini island: Structural 153. Karfakis I, Skourtsi-Koroneou B, Ioakim Chr, Kanaki-Mavridou evolution and kinematics during the Tertiary (, F (1993) Geological Map of Greece, scale 1:50,000, Moyzakion Greece). In R. Casale, M. Fytikas, G. Sigvaldasson & G. Sheet. Institute of Geology and Mineral Exploration, Athens. Vougioukalakis, (Eds.), Volcanic risk. The European laboratory [View Aricle] volcanoes, 2nd workshop. Computer Science Research 154. Chiari M, Bortolotti V, Marcucci MCh, Saccani E (2012) Development, 23-36. Radiolarian Biostratigraphy and Geochemistry of the Koziakas 140. Ring U, Layer PW (2003) High-pressure metamorphism in the Massif Ophiolites (Greece). Bulletin de la Société Géologique Aegean, eastern Mediterranean: underplating and exhumation from de France 183 : 287-306. [View Aricle]

J Geol Geosci 49 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

155. Nirta G, Moratti G, Piccardi L, Montanari D, Catanzariti R,et étude du métamorphisme et de l’ évolution magmatique des al. (2015) The boeotian flysch revisited: New constraints on zones internes des Hellénides. Ann Geol Pays Hellénique 20: ophiolite obduction in central Greece. Ofioliti 40: 107-123. 1-792. [View Aricle] [View Aricle] 169. Galeos A, Pomoni-Papaioannou F, Tsaila-Monopolis S, Turnsek 156. Ghon G (2017) Mikrofazielle Untersuchung einer D, Ioakim C (1994) Upper Jurassic-Lower Cretaceous molassic- karbonatklastischen Beckenfüllung im Hangenden der type sedimentation in the western part of the Almopias subzone, ophiolitführenden Koziakas Mélange in Kori, Nordgriechenland. Aridhea Loutra unit (northern Greece). Bull. Geol. Soc. Greece Bachelror Arbeit, University Leoben, 1-20. [View Aricle] 30: 171-184. [View Aricle] 157. Yarwood GA, Aftalion M (1976) Field relations and U-Pb 170. Photiades A, Skourtsi-Coroneou V, Grigoris P (1998) The geochronology of a granite from the Pelagonian zone of the stratigraphic and paleogeographic evolution of the eastern Hellenides (High Pieria, Greece). Bull. Soc. Géol. Fr., 18: 259- Pelagonian margin during the Late Jurassic – Cretaceous interval 264. [View Aricle] (Western Vermion Mountain - Western Macedonia, Greece). Bull. Geol. Soc. Greece 32: 71-77. [View Aricle] 158. Mountrakis D, Sapountzis E, Kilias A, Eleftheriadis G, Christofides G (1983) Paleogeographic conditions in the western 171. Photiades A, Carras N, Bortolotti V, Fazzuoli M, Principi G Pelagonian margin in Greece during the initial rifting of the (2007) The late Early Cretaceous transgression on the laterites continental area. Can. J. Earth Sci., 20: 1673-1681. [View Aricle] in Vourinos and Vermion massifs (western Μacedonia, Greece). Bull. Geol. Soc. Greece, XL 182-190. [View Aricle] 159. Kilias A, Mountrakis D (1989) The Pelagonian nappe. Tectonics, metamorphism and magmatism (in Greek with English abstract). 172. Bortolotti V, Carras N, Chiari M, Fazzuali M, Marcucci M, Bull. Soc. Geol. Greece, 20: 29-46. [View Aricle] Photiades A, Principi G (2002) The Late Jurassic carbonate platform of Zygosti, Vourinos-Pindos zone. Northern Greece. 160. Koroneos A, Christofides G, Del Moro A, Kilias A (1993) 6th Intern. Symp. of Jurassic System, Abst., 21, . [View Rb-Sr geochronology and geochemical aspects of the Eastern Aricle] Varnountas plutonite (NW Macedonia, Greece). Neues Jahrb. fur Mineral. Abhuandlungen, 165: 297-315. [View Aricle] 173. Gawlick HJ, Sudar M, Missoni S, Aubrecht R, Schlagintweit F, Jovanović D, Mikuš T (2020) Formation of a Late Jurassic 161. Poli G, Christophidis G, Koroneos A, Soldatos T, Perugini D, carbonate platform on top of the obducted Dinaridic ophiolites et al. (2009) Early Triassic granitic magmatism - Arnea and deduced from the analysis of carbonate pebbles and ophiolitic Kerkini granitic complexes - In the Vertiskos unit (Serbo- detritus in southwestern Serbia. [View Aricle] macedonian massif, north-eastern Greece) and its significance in the geodynamic evolution of the area. Acta Vulcanol., 21: 47-70. 174. Kostaki G, Kilias A, Gawlick HJ, Schlagintweit F (2014) [View Aricle] Component analysis in the vardar/Axios zone of northern Greece reveals an eroded Late Jurassic carbonate platform comparable 162. Michard A, Feinberg H, Montigny R (1998) Supra-ophiolitic to those of the Eastern Alps/Western Carpathian, Dinarides, formations from the Thessaloniki nappe (Greece), and associated Albanides and Hellenides. Bul. Shk. Gjeol., 1: 85-88. [View magmatism: An intra-oceanic subduction predates the Vardar Aricle] obduction. Comptes Rendus l’Academie Sci. - Ser. IIa Sci. la 175. Mposkos E, Krohe A (2004) New Evidences of the Low-P/High-T Terre des Planetes 327: 493-499. [View Aricle] Pre-Alpine Metamorphism and Medium-P Alpine Overprint of the 163. Most T, Frisch W, Dunkl I, Kodosa B, Boev B, et al. (2001) Pelagonia Zone Documented in Metapelites and Orthogneisses Geochonological and structural investigation of the Northern from the Voras Massif, Macedonia, Northern Greece. Bull. of the Pelagonian crystalline zone. Constraints from K/Ar and zircon Geol. Soc. Greece, XXXVI, 558-567. [View Aricle] and apatite fission track dating. Bull Geol Soc Greece 34: 91-95. 176. Schenker FL, Burg JP, Kostopoulos D, Moulas E, Larionov [View Aricle] A, Von Quadt A (2014) From mesoproterozoic magmatism to 164. Gawlick HJ, Missoni S (2019) Middle-Late Jurassic sedimentary collisional cretaceous anatexis: Tectonomagmatic history of melange formation related to ophiolite obduction in the Alpine- the Pelagonian Zone, Greece. Tectonics, 33: 1552-1576. [View Carpathian-Dinaric . Gondwana Research. Aricle] [View Aricle] 177. Tremblay A, Meshi A, Deschamps T, Goulet F, Goulet N (2015) 165. Sanchez-Gomez M, Avigad D, Heimann A (2002) Geochronology The Vardar zone as a suture for the Mirdita ophiolites, Albania: of clasts in allochthonous Miocene sedimentary sequences on Constraints from the structural analysis of the Korabi-Pelagonia and Paros Islands: implications for back-arc extension zone. Tectonics 34: 352-375. [View Aricle] in the Aegean Sea. 159: 45-60. [View Aricle] 178. Robertson A, Shallo M (2000) Mesozoic-Tertiary tectonic 166. Kruckenberg SC, Ferré EC, Teyssier C, Vanderhaeghe O, evolution of Albania in its regional Eastern Mediterranean Whitney DL, et al. (2010) Viscoplastic flow in migmatites context. Tectonophysics 316: 197-254. [View Aricle] deduced from fabric anisotropy: an example from the Naxos 179. Brown SAM, Robertson AHF (2004) Evidence for Neotethys dome, Greece. J. Geophys. Res, Solid Earth 115: 1978-2012. rooted within the Vardar suture zone from the Voras Massif, [View Aricle] northernmost Greece. Tectonophysics 381: 143-173. [View 167. Cao S, Neubauer F, Bernroider M, Liu J (2013) The lateral Aricle] boundary of a metamorphic core complex: the Moutsounas shear 180. Brown SAM, Robertson AHF (2003) Sedimentary geology as zone on Naxos, Cyclades, 54: 103-128. [View Aricle] a key to understanding the tectonic evolution of the Mesozoic- Early Tertiary Paikon Massif, Vardar suture zone, N Greece. 168. Mercier J (1968) Étude géologique des zones internes des Sediment. Geol., 160: 179-212. [View Aricle] Hellénides en Macédoine centrale (Grèce). Contribution é l’

J Geol Geosci 50 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

181. Jacobshagen V, Dürr F, Kockel K, Kopp KO, Kowalczyk G, et low-grade schists of the Circum-Rhodope Belt in the eastern al. (1978) Structure and geodynamic evolution of the Aegean Rhodope–Thrace region, Bulgaria–Greece. J. Geodyn. 52: region, in: Cloos H, Roeder D, Schmidt K, (eds), IUGG, S. (Ed.), pp143–167. [View Article] Alps, Apennines, Hellenides 537-564. [View Aricle] 197. Koglin N, Kostopoulos D, Reischmann T (2009) Geochemistry, 182. Hoxha L (2001) The Jurassic-Cretaceous orogenic event and its petrogenesis and tectonic setting of the Samothraki mafic suite, effects in the exploration of sulphide ores, Albanian ophiolites, NE Grecce: trace-element, isotopic and zirkon age constraints. Albania. Eclogae Geol. Helv. 94: 339-350. [View Aricle] Tectonophysics, 473: pp53-68. [View Article] 183. Ferrière J (1974) Étude géologique d`un sectuer des zones 198. Kilias A (2019) Architecture of the Alpine Deformation and Helléniques internes subpelagonienne et pélagonienne (massif Geotectonic Setting of the Hellenides. A synthesis. Proceedings de l`Othrys, Grèce continental). Importance et signification de l of the 15th International Congress of the Geol. Soc. Grrecce, période orogénique ante-Cretacé superieur. Bul. de la Soc. Géol. Bull. Geol. Soc. Greece, Sp. Publ. [View Article] de France, XVI 543-562. [View Aricle] 199. Moritz R, Jacquat S, Chambefort I, Fontignie D, Petrunov R, et 184. Carras N (1995) La piattaforma carbonatica del Parnasso durante al. (2003) Controls on ore formation at the high-sulphidation Au– il Guirassico Superiore - Cretaceo inferiore. PhD Thesis, Uni. Cu Chelopech deposit, Bulgaria: evidence from infrared fluid Athens 232 pp. [View Aricle] inclusion microthermometry of enargite and isotope systematics 185. Celet P (1962) Contribution a l` étude géologique du Parnasse- of barite. In: Eliopoulos, D. et al. (eds), Mineral exploration and Gkiona et d` une partie des régions méridionales de la Grèce sustainable development, Millpress, Rotterdam, pp1209–1212. continental. Ann. Géol. Pays Hellén. 13: 1-360. [View Aricle] [View Article] 186. Celet P (1977) Les bordures de la zone du Parnasse. `Evolution 200. Peytcheva I, von Quadt A, Kouzmanov K, Bogdanov K (2003) paleogéographique au Mésozoique et caractères structuraux. VI Elshitsa and Vlaykov Vruh epithermal and porphyry Cu (–Au) Coll. Aegean, 725-740. [View Aricle] deposits of central Srednogorie, Bulgaria: source and timing of 187. Clement B (1977) Relations structurales entre la zone du magmatism and mineralisation. In: Eliopoulos, D. et al. (ed) Parnasse et la zone Pelagonienne en Beotie. VI Coll. Aegean, Mineral exploration and sustainable development. Millpress, 237-251. [View Aricle] Rotterdam, pp371–374. [View Article] 188. Carras N, Fazzuoli M (1992) La Formation des “Calcaires de 201. von Quadt A, Peytcheva I, Cvetkovic V (2003) Geochronology, Amfissa” (“Intermediate Limestones Auctt.), Cretacé inferieur, geochemistry and isotope tracing of the Cretaceous magmatism Zone du Parnasse (Grèce continentale). Ann. Géol. des Pays of east-Serbia and Panagyurishte District (Bulgaria) as part of Helléniques 35: 43-101. [View Aricle] the Apuseni–Timok–Srednogorie metallogenic belt in eastern Europe. In: Eliopoulos, D. et al. (eds) Mineral exploration and 189. Anders B, Reischmann T, Poller U, Kostopoulos D (2005) Age sustainable development, Millpress, Rotterdam, pp407–410. and origin of granitic rocks of the eastern Vardar Zone, Greece: new constraints on the evolution of the Internal Hellenides. J. [View Article] Geol. Soc. London 162: 857-870. [View Aricle] 202. Marchev P, Kaiser-Rohrmeier M, Heinrich C, Ovtcharova M, 190. Robertson AHF, Karamata S, Saric K (2009) Overview of von Quadt A, et al. (2005) 2: Hydrothermal ore deposits related ophiolites and related units in the Late Paleozoic-Early Cenozoic to post-orogenic extensional magmatism and core complex magmatic and tectonic developmemt of Tethys in the northern formation: The Rhodope Massif of Bulgaria and Greece. Ore part of the Balkan region. Lithos 72: 1-36. [View Aricle] Geol. 27: pp53-89. [View Article] 191. Bonneau M, Godfriaux I, Moulas Y, Fourcade E, Masse J (1994) 203. von Quadt A, Moritz R, Peytcheva I, Heinrich CA (2005) Stratigraphie et structure de la bordure orientale de la double Geochronology and geodynamics of Late Cretaceous magmatism fenêtre du Paikon (Macédoine, Grèce). Bull. Geol. Soc. Greece and Cu–Au mineralization in the Panagyurishte region of the 30: 105-114. [View Aricle] Apuseni–Banat–Timok–Srednogorie belt, Bulgaria. Ore Geol. Rev, 27: pp95–126. [View Article] 192. Zachariadis P (2007) Ophiolites of the eastern Vardar Zone. PhD Thesis, Johannes Gutenberg Universität, Mainz, p. 125. [View 204. Robertson AHF (2002) Overview of the genesis and emplacement Aricle] of Mesozoic ophiolites in the Eastern Mediterranean region. Lithos, 65: pp1-68. [View Article] 193. Chiari M, Bortolotti V, Marcucci M, Photiades A, Principi G (2003) The Middle jurassic siliceous sedimentary cover at the top of the 205. Ustaszewski K, Schmid SM, Lugović B, Schuster R, Schaltegger vourinos ophiolite (Greece). Ophioliti 28: 95-103. [View Aricle] U, et al. (2009) Late Cretaceous intra-oceanic magmatism in 194. Frisch W, Meschede M (2007) Plattentektonik: the internal Dinarides (northern Bosnia and Herzegovina): Kontinentverschiebung und Gebirgsbildung. 2., aktualisierte Implications for the collision of the Adriatic and European Auflage, WBG, Darmstad, p. 196. [View Aricle] plates. Lithos, 108: pp106–125. [View Article] 195. Bonev N, Stampfli G (2008) Petrology, geochemistry and 206. Ring U, Glodny J, Will T, Thomson S (2010) The Hellenic geodynamic implications of Jurassic island arc magmatism as Subduction System: High-Pressure Metamorphism, Exhumation, revealed by mafic volcanic rocks in the Mesozoic low-grade Normal Faulting, and Large-Scale Extension. Annu. Rev. Earth sequence, eastern Rhodope, Bulgaria. Lithos, 100: pp210–233. Planet. Sci, 38: pp45–76. 170910. [View Article] [View Article] 207. Ring U, Will T, Glodny J, Kumerics C, Gessner K, et al. (2007) 196. Bonev N, Stampfli G (2011) Alpine tectonic evolution of Early exhumation of high-pressure rocks in extrusion wedges: a Jurassic subduction-accretionary complex: deformation, Cycladic blueschist unit in the eastern Aegean, Greece, and kinematics and 40Ar/39Ar age constraints on the Mesozoic Turkey. Tectonics. 26: TC2001 [View Article]

J Geol Geosci 51 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

208. Keay S (1998) The geological evolution of the Cyclades, Greece: 224. Zagorchev I (2001) Introduction to the geology of SW Bulgaria. constraints from SHRIMP U-Pb geochronology. PhD thesis. Geologica Balcanica, 31: pp3–52. [View Article] Aust. Natl. Univ., Canberra, pp1-335. [View Article] 225. Dinter DA, Macfarlane A, Hames W, Isachsen C, Bowring S, 209. Tomaschek F, Kennedy A K, Villa I M, Lagos M, Ballhaus C, et al. (1995) U-Pb and 40Ar/39Ar geochronology of the Symvolon (2003) Zircons from , Cyclades, Greece-Recrystallization granodiorite: Implications for the thermal and structural evolution and mobilization of zircon during high-pressure metamorphism, of the Rhodope metamorphic core complex, northeastern Greece. J. Petrol, 44: pp1977–2002. [View Article] Tectonics, 14: pp886–908. [View Article] 210. Avigad D, Garfunkel Z, Jolivet L & Azanon JM (1997) Back arc 226. Sokoutis D, Brun JP, Van Den Driessche J, Pavlides S (1993) extension and denudation of Mediterranean eclogites. Tectonics, A major Oligo-Miocene detachment in southern Rhodope 16: pp924–941. [View Article] controlling north Aegean extension. J. Geol. Soc. London, 150: pp243–246. [View Article] 211. Kilias A, Mountrakis D (1990) Kinematics of the crystalline sequences in the western Rhodope massif. Geol. Rhodopica, 2: 227. Dinter DA, Royden L (1993) Late Cenozoic extension in pp100–116. [View Article] northeastern Greece: Strymon Valley detachment system and Rhodope metamorphic core complex. Geology. 21: pp45-48. 212. Pavlides S, Mountrakis D, Kilias A, Tranos M (1990) The [View Article] role of strike-slip movements in the extensional area of the northern Aegean (Greece). A case of transtetional tectonics. Ann. 228. Soldatos T, Koroneos A, Christophidis G, Del Moro A (2001a) Tectonicae, 4: pp196–211. [View Article] Geochronology and origin of the Elatia plutonite (Hellenic Rhodope Massif, N. Greece) constrained by new Sr isotopic 213. Burg JP, Ricou LE, Ivanov Z, Godfriaux I, Dimov D, et al. data. N. Jb. Mineral. Abh, pp179-209. [View Article] (1996) Syn-metamorphic nappe complex in the rhodope massif. Structure and kinematics. Terra Nova, 8: pp6–15. [View Article] 229. Soldatos T, Koroneos A, Del Moro A, Christophidis G (2001b) Evolution of the Elatia plutonite (Hellenic Rhodope Massif, N. 214. Kilias A, Falalakis G, Mountrakis D (1999) Cretaceous-Tertiary Greece). Chemie der Erde, 61: pp92-116. [View Article] structures and kinematics of the Serbomacedonian metamorphic rocks and their relation to the exhumation of the Hellenic 230. Soldatos T, Koroneos A, Kamenov BK, Peytcheva I, von Quadt hinterland (Macedonia, Greece). Int. J. Earth Sci, 88: pp513– A, et al. (2008) New U–Pb and Ar–Ar mineral ages for the 531. [View Article] Barutin-Buynovo-Elatia-Skaloti- batholith (Bulgaria and Greece): refinement of its debatable age. Geochem. Miner. 215. Tranos M, Kilias a, D M (1999) Geometry and kinematics of Pet., 46: pp85–10. [View Article] the Tertiary post-metamorphic Circum Rhodope Belt Thrust System (CRVTS), Northern Greece. Bull. Soc. Geol. Greece, 33: 231. Marchev P, Raicheva R, Downes H, Vaselli O, Chiaradia M, et pp5–16. [View Article] al. (2004) Compositional diversity of Eocene-Oligocene basaltic magmatism in the Eastern Rhodopes, SE Bulgaria: Implications 216. Kilias A, Mountrakis D (1998) Tertiary extension of the Rhodope for genesis and tectonic setting. Tectonophysics, 393: pp301– massif associated with granite emplacement (Northern Greece). 328. [View Article] Acta Vulcanol, 10: pp331–337. [View Article] 232. Marchev P, Georgiev S, Raicheva R, Peytcheva I, von Quadt 217. Krohe A, Mposkos E (2002) Multiple generations of extensional A, et al. (2013) Adakitic magmatism in post-collisional setting: detachments in the Rhodope Mountains (northern Greece): An example from the Early-Middle Eocene Magmatic Belt in Evidence of episodic exhumation of high-pressure rocks, Southern Bulgaria and Northern Greece. Lithos, 180–181: Geological Society London, Special Publication, 204: pp151- pp159–180. [View Article] 178. [View Article] 233. Georgieva M, Cherneva Z, Kolcheva K, Sarov S, Gerdjikov I, et 218. Brun J P, Sokoutis D (2007) Kinematics of the Southern al. (2002) Р-Т metamorphic path of sillimanitebearing schists in an Rhodope Core Complex (North Greece). Int. J. Earth Sci. 96: extensional shear zone, Central Rhodopes, Bulgaria. Geochemistry, pp1079–1099. [View Article] Mineralogy and Petrology, 39: pp95-106. [View Article] 219. Turpaud P, Reischmann T (2010) Characterization of igneous 234. Georgieva M, Bosse V, Cherneva Z & Kirilova M (2011) terranes by zircon dating: implications for UHP occurrences and Products of HP melting in Chepelare shear zone, Central suture identification in the Central Rhodope, northern Greece. Rhodope, Bulgaria: petrology, P–T estimates and U–Th–Pb Int. J. Earth Sci, 99: pp567–591. [View Article] dating. Bulgarian Geological Society Annual Conference 220. Kronberg P, Meyer W, Pilger A (1970) Geologie der Rila-Rhodope- ‘Geosciences’, Sofia, pp55–56. [View Article] Masse zwischen Strimon und Nestos (Nordgriechenland). Geol. 235. Gautier P, Bosse V, Cherneva Z, Didier A, Gerdjikov I, et al. Jahrb. 88: pp133–180. [View Article] (2017) Polycyclic alpine orogeny in the Rhodope metamorphic 221. Kronberg P, Raith M (1977) Tectonics and metamorphism of the core complex: the record in migmatites from the Nestos shear Rhodope Crystalline Complex in Eastern Greek Macedonia and zone (N. Greece). Bull. Soc. géol. Fr, 188: pp1-28. [View Article] parts of Western Thrace. N. Jb. Geol. Paläont. Mh., 11: pp697– 236. Wuethrich ED (2009) Low temperature thermochronology of the 704. [View Article] Northern Aegean Rhodope massif. PhD Thesis, ETH Zuerich, 222. Zagorchev I, Dinkova I (1989) Geological map of Bulgaria pp1-209. [View Article] on the Scale 1:100000. Map sheet Strumitsa, Petrich, Gevgeli, 237. Mposkos E, Krohe A (2006) Pressure-temperature-deformation Sidirocastron. Geology and Geophysics Ltd, Sofia. [View Article] paths of closely associated ultra-high-pressure (diamond-bearing) 223. Zagorchev I (1996) Geological heritage of the Balkan Peninsula: crustal and mantle rocks of the Kimi complex: implications for geological setting (an overview). Geologica Balcanica, 26: pp3– the tectonic history of the Rhodope Mountains, northern Greece. 10. [View Article] Can. J. Earth Sci., 43: pp1755–1776. [View Article]

J Geol Geosci 52 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

238. Liati A, Seidel E (1996) Metamorphic evolution and 252. Kydonakis K, Moulas E, Chatzithedoridis E, Brun JP, geochemistry of kyanite eclogites in central Rhodope, northern Kostopoulos D (2015) First-report on Mesozoic eclogite-facies Greece. Contrib. to Mineral. Petrol., 123; pp293–307. [View metamorphism preceding Barrovian overprint from the western Article] Rhodope. Lithos, 220-223: pp147-163. [View Article] 239. Liati A, Gebauer D, Wysoczanski R (2002) U-Pb SHRIMP-dating 253. De Wet AP (1989) Geology of a part of the Chalkidiki peninsula, of zircon domains from UHP garnet-rich mafic rocks and late Northern Greece. PhD-Thesis, University of Cabridge, United pegmatoids in the Rhodope zone (N Greece); evidence for Early Kingdom, pp1-245. [View Article] Cretaceous crystallization and Late Cretaceous metamorphism. 254. De Wet AP, Miller JA, Bickle MJ, Chapman HJ (1989) Chem. Geol., 184: pp281–299. [View Article] Geology and geochronology of the Arnea, Sithonia and 240. Kockel F, Mollat H, Walther HW (1971) Geologie des Serbo- Ouranopolis intrusions, Chalkidiki peninsula, Northern Greece. Mazedonischen Massivs und seines mesozoischen Rahmens Tectonophysics, 161: pp65-79. [View Article] (Nordgriechenland). Geol. Jahrb., 89: pp529–551. [View 255. Anti´c M, Peytcheva I, von Quadt A, Kounov A, Trivi´c B, Article] et al. (2015) Pre-Alpine evolution of a segment of the North- 241. Chatzidimitriadis E, Kilias A, Staikopoulos G (1985) Nouvi Gondwanan margin: Geochronological and geochemical aspetti petrologici e tettonici del massiccio serbomacedonne e evidence from the central SerboMacedonian Massif. Gondwana delle regioni adiacenti, della Grecia del Nortd. Boll. Soc. Geol. Researche, 36: pp523-544. [View Article] Italia, 104: pp515–526. [View Article] 256. Kydonakis K, Gallagher K, Brun JP, Jolivet M, Gueydan F, et al. 242. Himmerkus F, Reischmann T, Kostopoulos D (2007) Gondwana- (2014) Upper Cretaceous exhumation of the western Rhodope derived terranes in the northern Hellenides. 4-D Framew. Cont. Metamorphic Province (Chalkidiki Peninsula, northern Greece), Crust, 200: pp379–390. [View Article] Tectonics, 33: pp1113–1132. [View Article] 243. Himmerkus F, Reischmann T, Kostopoulos D (2009b) Triassic 257. Kaufmann G, Kockel F, Mollat H (1976) Notes on the stratigraphic rift-related meta-granites in the Internal Hellenides, Greece. palaeogeographical position of the Svoula Formation in the Geol. Mag. 146: pp252–265. [View Article] innermost zone of the Hellenides, Northern Greece. Bull. la Société Géologique Fr. 18: pp225–230. [View Article] 244. Dixon JE, Dimitriadis S (1984) Metamorphosed ophiolitic rocks from the Serbo-Macedonian Massif, near Lake Volvi, North-east 258. Meinhold G, Kostopoulos D, Reischmann T, Frei D, BouDagher- Greece, Geological Society Special Publication. [View Article] Fadel MK (2009) Geochemistry, provenance and stratigraphic age of metasedimentary rocks from the eastern Vardar 245. Papadopoulos Ch, Kilias A (1985) Altersbeziehungen suture zone, northern Greece. Palaeogeogr. Palaeoclimatol. zwischen metamorphose und deformation im zentralen Palaeoecol., 277: pp199–225. [View Article] Teil des serbomazedonischen massivs (Vertiskos Gebirge,Nordgriechenland). Geol. Rundschau, 74: pp77–85. 259. Meinhold G, Kostopoulos DK (2013) The Circum-Rhodope [View Article] Belt, northern Greece: Age, provenance, and tectonic setting. Tectonophysics, 595–596: pp55–68. [View Article] 246. Brun JP, Sokoutis D (2018) Core complex segmentation in North Aegean, a dynamic view. Tectonics. 37: pp1797-1830. [View 260. Michard A, Goffe B, Liati A, Mountrakis D (1994) First evidence Article] of blueschist-facies metamorphism in the Circum-Rhodope nappes. Internal Hellenides, Greece. Comptes Rendus - Acad. 247. Bauer C, Rubatto D, Krenn K, Proyer A, et al. (2007) A zircon study des Sci. Comptes Rendus - Acad. des Sci. Ser. II Sci. la Terre des from the Rhodope metamorphic complex, N-Greece: Time record Planetes, 318: pp1535–1542. [View Article] of a multistage evolution. Lithos, 99: pp207–228. [View Article] 261. Gorinova T, Georgiev N, Cherneva Z, Naydenov K, Grozdev V, 248. Macheva L, Peytcheva I, von Quadt A, Zidarov N, Tarassova et al. (2019) Kinematics and time of emplacement of the Upper E (2006) Petrological, geochemical and isotope features Allochthon of the Rhodope Metamorphic Complex: evidence of Lozen metagranite, Belasitza Mountain – evidence for from the Rila Mountains, Bulgaria. Inter. J. of Earth Sci. 108: widespread distribution of Ordovician metagranitoids in the pp2129-2152. [View Article] Serbo-Macedonian Massif, SW Bulgaria, in: Proceedings of the National Conference “GEOSCIENCES 2006”. S., BGS, pp209– 262. Pe-Piper G, Doutsos T, Mijara A (1993a) Petrology and 212. [View Article] regional significance of the Hercynian granitoid rocks of the Olympiada area, northern Thessaly, Greece. Chemie der Erde - 249. Himmerkus F, Reischmann T, Kostopoulos D (2009a) Serbo- Geochemistry, 53: pp21–36. [View Article] Macedonian revisited: A Silurian basement terrane from northern Gondwana in the Internal Hellenides, Greece. Tectonophysics, 263. Pe-Piper G, Doutsos T, Mporonkay C (1993b) Structure, 473: pp20–35. [View Article] geochemistry and mineralogy of Hercynian granitoid rocks of the Verdikoussa area, northern Thessaly, Greece and their 250. Dimitriadis S, Godelitsas A (1991) Evidence for high pressure regional significance. Neues Jahrb. fur Mineral. Abhandlungen, metamorphism in the Vertiskos group of the Serbomacedonian 165: pp267–296. [View Article] massif. The eclogite of Nea Roda, Chalkidiki. Bull. Geol. Soc. Greece, 25: pp67–80. [View Article] 264. Koroneos A (2010) Petrogenesis of the Upper Jurassic Monopigadon pluton related to the Vardar/Axios ophiolites 251. Kostopoulos DK, Ioannidis NM, Sklavounos SA (2000) A (Macedonia, northern Greece) and its geotectonic significance. new occurrence of ultrahigh-pressure metamorphism, central Chemie der Erde - Geochemistry, 70: pp221–241. [View Article] Macedonia, northern Greece: Evidence from graphitized diamonds? Int. Geol. Rev., 42: pp545–554. [View Article] 265. Boccaletti M, Manetti P, Peccerillo A, Stanisheva-Vasileva G (1978) Late Cretaceous high-potassium volcanism in eastern

J Geol Geosci 53 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

Srednogorie, Bulgaria, Geol. Soc. Am. Bull., 89: pp439 –447. 282. Spray JG, Roddick JC (1980) Petrology and 40Ar/39Ar [View Article] geochronology of some hellenic sub-ophiolite metamorphic rocks. Contrib. to Mineral. Petrol., 72: pp43–55. [View Article] 266. Royden LH (1993) Evolution of retreating subduction boundaries formed during continental collision. Tectonics, 12: pp629–638. 283. Gawlick HJ, Frisch W (2003) The Middle to Late Jurassic [View Article] carbonate clastic radiolaritic flysch sediments in the Northern Calcareous Alps: sedimentology, basin evolution and tectonics 267. Georgiev N, Henry B, Jordanova N, Froitzheim N, Jordanova - an overview.Neues Jahrbuch Geologie Paläontologie, D, et al. (2009) The emplacement mode of Upper Cretaceous Abhandlungen, 230: pp163-213. [View Article] plutons from the southwestern part of the Sredna Gora Zone (Bulgaria): structural and AMS study. Geol. Carpath., 60: pp15– 284. Gawlick HJ, Missoni S, Suzuki H, Sudar NM, Lein R, et al. 33. [View Article] (2016) Triassic radiolarite and carbonate components from a 268. Seward D, Vanderhaeghe O, Siebenaller L, Thomson S, Hibsch Jurassic ophiolitic melange (Dinaridic Ophiolite Belt). Swiss. J. C, et al. (2009) Cenozoic tectonic evolution of Naxos Island Geosci. 109: pp473-494. [View Article] through a multi-faceted approach of fission-track analysis.Geol. 285. Marku D (2002) Report of the Project V1b Cretaceous of the Soc. London, Spec. Publ., 321: pp179–196. [View Article] Zepe-Guri i Nuses area. Central Archives Albanian Geological 269. Soldatos K (1955) The volcanics of the Almopias area. PhD Survey, pp1-62. [View Article] Thesis, Univ. of Thessaloniki, Greece. pp120. [View Article] 286. Peza LH, Markou D (2002) Lower Cretaceous in the 270. Eleftheriades G (1977) Contribution to the Study of the Munella Mountain (Mirdita Zone, northeastern Albania). Volcanic Rocks of the Southern Almopia. PhD Thesis, Univ. of Oesterreichische Akademie der Wissenschaften, Schriftenreihe Thessaloniki, Greece, pp120. [View Article] der Erdwissenschaftlichen Kommission, 15: pp365-372. [View Article] 271. Fytikas M, Innocenti F, Manetti P, Peccerillo A, Mazzuoli R, et al. (1984) Tertiary to Quaternary evolution of volcanism in the 287. Thomson S N, Stöckhert B, Brix M R (1998) Thermochronology Aegean region, Geological Society London, Special Publication. of the high-pressure metamorphic rocks of Crete, Greece: 17: pp687-699. [View Article] Implications for the speed of tectonic processes. Geology, 26: pp259–262. [View Article] 272. Vougioukalakis G (1994) The Pliocene volcanites of the Voras mountain, Central Macedonia, Greece. Bull. Geol. Soc. Greece, 288. Most T (2003) Geodynamic evolution of the Eastern Pelagonian pp223-240. [View Article] Zone in northwestern Greece and the Republic of Macedonia: Implications from U/Pb, Rb/Sr, K/Ar, 40Ar/39Ar geochronology 273. Pe-Piper, G., Piper, D.J.W., 2002. The igneous rocks of Greece: The and fission track thermochronology. PhD Thesis, Eberhardt- anatomy of an orogen. Gebrüder Borntraeger, Berlin. [View Article] Karls-Universität Tübingen, pp198. [View Article] 274. Vougioukalakis GE, Satow CS, Druitt TH (2019) Volcanism of 289. Baroz F, Bebien J, Ikenne M (1987) An example of high-pressure/ the South Aegean Volcanic Arc. Elements, 15: pp159-164. [View low- temperature metamorphic rocks from an island arc: the Article] Paikon Series (Innermost Hellenides, Greece). J. Metamorph. 275. Jones G, Robertson AHF (1991) Tectono-stratigraphy and evolution Geol. 5: pp509–527. [View Article] of the Mesozoic Pindos ophiolite and related units , northwestern 290. Ozsvárt P, Kovács S (2012) Revised Middle and Late Triassic Greece. J. Geol. Soc. London., 148: pp267–288. [View Article] radiolarian ages for ophiolite mélanges: implications for the 276. Jones G, Robertson AHF (1994) Rift-drift-subduction and geodynamic evolution of the northern part of the early Mesozoic empacement historyof the Early Mesozoic Pindos ocean: Neotethyan subbasins. Bull. Soc. Geol. France, 183: pp273-286. Evidence from the Avdella melange, Northern Greece. Bull. [View Article] Geol. Soc. Greece, 30: pp45-58. [View Article] 291. Orozco M, Alonso-Chaves F M, Nieto F (1998) Development 277. Chiari M, Bortolotti V, Marcousi M, Principi G (2007) New data of large north-facing folds and their relation to crustal extension on the age of the Simoni Mélange, northern Mirdita ophiolite in the Albora´n domain (Alpujarras region, Betic Cordilleras, nappe, Albania. Ophioliti, 32: pp53-56. [View Article] Spain). Tectonophysics, 298: pp271–295. [View Article] 278. Mercier J, Vergely P (1972) Les mélanges ophiolitiques 292. Orozco M, Alonso-Chaves F M (2011) Kilometre-scale sheath de Macédonie (Grèce): Décrochements d‘âge anté Cretacé folds in the western Betics (south of Spain. Int. J. Earth Sci. supérieur: Zeitschrift der Deutschen Geologischen Gessellschaft, (Geol. Rundsch.). 101: pp505-519. [View Article] 123: pp469–489. [View Article] 293. Froitzheim N (1992) Formation of recumbent folds during 279. Vergely P (1976) Chevauchement vers l` ouest et retrochariage synorogenic crustal extension (Austroalpine nappes, vers l`est des ophiolites: deux phases tectoniques au course du Switzerland). Geology, 20: pp923–926. [View Article] Jurassique supérier-Cretacé dans les Hellénides internes. Bul. Géol. Soc. France, 18: pp231-244. [View Article] 294. Avgerinas A (2014) Deformation and kinematics of the Pelagonian zone in Northern Greece. PhD Thesis, University of 280. Nirta G, Bortolotti V, Chiari M, Menna F, Saccani E, et al. Thessaloniki, pp1-320. [View Article] (2010) Ophiolites from the Grammos-Arrenes area, northern Greece:geological, paleontological and geochemical data. 295. Georgiev N, Henry B, Jordanova N, Jordanova D, Naydenov K Ofioliti, 35: pp103–15. [View Article] (2014) Emplacement and fabric-forming conditions of plutons from structural and magnetic fabric analysis: a case study of the 281. Nirta G, Moratti G, Piccardi L, Montanari D, Carras N, et al. Plana pluton (Central Bulgaria). Tectonophysics, 629: pp138– (2018) From obduction to continental collision: new data from 154. [View Article] Central Greece. Geol. Mag., 155: pp377-421. [View Article]

J Geol Geosci 54 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

296. Thiebault F (1982) Evolution géodynamique des Hellénides 311. Xypolias P, Iliopoulos I, Chatzaras V, Kokkalas S (2012) externes en Péloponnèse méridional (Grèce). Soc. Géol. Nord Subduction- and exhumation-related structures in the Cycladic Publ., 6: pp574-596. [View Article] Blueschists: Insights from south Evia Island (Aegean region, Greece). Tectonics, 31. [View Article] 297. Thiebault F, Triboulet T (1984) Alpine metamorphism and deformation in Phyllite nappes (External Hellenides,southern 312. Xypolias P, Spanos D, Chatzaras V, Kokkalas S, Koukouvelas Peloponnesus, Greece): geodynamic implication. Journal of I (2010) Vorticity of flow in ductile thrust zones: examples Geology, 92: pp185-199. [View Article] from the Attico-Cycladic Massif (Internal Hellenides, Greece). In R. D. Law, R. Butler, B. Holdsworth, M. Krabbendam & 298. Doutsos Th, Koukouvelas I, Poulimenos G, Kokkalas S, R. Strachan, (Eds.), Continental tectonics and mountain Xypolias P, et al. (2000) An Exhumation model for the south building. Geol. Soc. London Spec. Publ., 335: pp687–714. Pelopenessus, Greece. Int. J. Earth Sci., 89: pp350-365. [View [View Article] Article] 299. Xypolias P, Doutsos T (2000) Kinematics of rock flow in a 313. Schwartz S, Stoeckhert B (1996) Pressure solution in siliciclastic crustalscale shear zone: implication for the orogenic evolution of HP-LT metamorphic rocks -constraints on the state of stress in the southwestern Hellenides. Geological Magazine, 137: pp81 deep levels of accretionary complexes. Tectonophysics, 255: –96. [View Article] pp203-209. [View Article] 300. Papazachos BC, Delibasis ND (1969) Tectonic stress field and 314. Xypolias P, Kokkalas S (2006) Heterogeneous ductile deformation seismic faulting in the area of Greece. Tectonophysics, 7: pp231– along a mid-crustal extruding shear zone: an example from the 255. [View Article] External Hellenides (Greece). In R. D. Law, M. P. Searle & L. Godin, (Eds.), Channel flow, ductile extrusion and exhumation 301. Papanikolaou D, Lykoussis V, Chronis G, Pavlakis P (1988) A in continental collision zones. Geol. Soc. London Spec. Publ., comparative study of neotectonic basins across the Hellenic Arc: 268: pp497–516. [View Article] The Messiniakos, Argolikos and Southern Evoikos Gulfs. Basin Res., 1: pp167–176. [View Article] 315. Papanikolaou D, Vassilakis E (2010) Thrust faults and extensional detachment faults in Cretan tectono-stratigraphy: 302. Pavlides S, Kondopoulou DP, Kilias AA, Westphal M (1988) Implications for Middle Miocene extension. Tectonophysics, Complex rotational deformations in the Serbo-Macedonian 488: pp233–247. [View Article] massif (north Greece): structural and paleomagnetic evidence. Tectonopfysics, 145: pp329-335. [View Article] 316. Brun JP, Faccenna C (2008) Exhumation of high-pressure rocks driven by slab rollback. Earth Planet. Sci. Lett., 272: pp1-7. 303. Meulenkamp JE, Jonkers A, Sppak P (1977) Late Miocene to [View Article] early Pliocene development of Crete. VI Col Geol Aegean region, Athens, pp137-149. [View Article] 317. Dimitriadis S, Kondopoulou D, Atzemoglou A (1998) Dextral rotation and tectonomagmatic evolution of the southern Rhodope 304. Hatzfeld D, Kassaras I, Panagiotopoulos D, Amorese D, and adjacent regions (Greece), Tectonophysics, 299: pp159-173. Makropoulos K, et al. (1995) Microseimicity and strain pattern in [View Article] northwestern Greece. Tectonics, 14: pp773–785. [View Article] 318. Froitzheim N, Weber W, Nagel J Th, Ibele T and Furrer H 305. Papazachos BC, Papazachou CC (2002) The earthquakes of (2012) Late Cretaceous extension overprinting a steep belt in the Greece: Thessaloniki, Ziti publications, pp315. [View Article] Northern Calcareous Alps (Schesaplana, Rätikon, Switzerland 306. Tranos MD, Papadimitriou EE, Kilias AA (2003) Thessaloniki and Austria). Inter. J. Earth Sci., 101: pp1315–1329. [View - Gerakarou Fault Zone (TGFZ): The western extension of Article] the 1978 Thessaloniki earthquake fault (Northern Greece) and 319. Kilias A, Falalakis G, Sfeikos A, Papadimitriou E, Vamvaka seismic hazard assessment. J. Struct. Geol., 25: pp2109–2123. A, et al. (2011) Architecture of Kinematics and Deformation [View Article] History of the Tertiary Supradetachment Thrace Basin: Rhodope 307. Carras N, Fazzuali M, Photiades A (2004) Transition from Province (NE Greece). New Frontiers in Tectonic Research - At carbonate platform to pelagic deposition (Mid Jurassic to Late the Midst of Plate Convergence, pp241-268. [View Article] Cretaceous), Vourinos massif, Northern Greece. Rivista Italiana 320. Okay A, İşintek I, Altıner D, Özkan-Altıner S, Okay N (2012) de Paleontologia e Stratigrafa, 110: pp345-355. [View Article] An olistostrome–mélange belt formed along a suture: Bornova 308. Kolokotroni CN, Dixon JE (1991) The origin and emplacement Flysch zone, western Turkey. Tectonophysics, 568–569: pp282– of the Vrondou granite, NE Greece. Bull. Geol. Soc. Greece, 25: 295. [View Article] pp469-483. [View Article] 321. Ramsay GJ, Huber IM (1983-87) The Techniques of Modern 309. Gautier P, Brun JP (1994) Crustal-scale geometry and kinematics Structural Geology. Academic Press, New York. 1-2. [View of late-orogenic extension in the central Aegean (Cyclades and Article] Evvia island): Tectonophysics, 238: pp399–424. [View Article] 322. Šarić K, Cvetković V, Romer RL, Christofides G, Koroneos A 310. van Hinsbergen DJ J, Zachariasse WJ, Wortel M J R, (2009) Granitoids associated with East Vardar ophiolites (Serbia, Meulenkamp JE (2005) Underthrusting and exhumation: A F.Y.R. of Macedonia and northern Greece): Origin, evolution comparison between the External Hellenides and the ‘‘hot’’ and geodynamic significance inferred from major and trace Cycladic and ‘‘cold’’ South Aegean core complexes (Greece). element data and Sr-Nd-Pb isotopes. Lithos, 108: pp131–150. Tectonics, 24: pp1-19. [View Article] [View Article]

J Geol Geosci 55 Volume 5(1): 2021 Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis

323. Schneider D, Grasemann B, Lion A, Soukis K, Draganits E 324. Spray JG, Bebien J, Rex DC, Roddick JC (1984) Age constraints (2018) Geodynamic significance of the Santorini Detachment on the igneous and metamorphic evolution of the Hellenic- System (Cyclades, Greece). Terra Nova, 30: pp414–422. [View Dinaric ophiolites. Geol. Evol. East. Mediterr., 17: pp619–628. Article] [View Article]

Citation: Kilias A (2021) The Hellenides: A Multiphase Deformed Orogenic Belt, its Structural Architecture, Kinematics and Geotectonic Setting during the Alpine Orogeny: Compression vs Extension the Dynamic Peer for the Orogen Making. A Synthesis. J Geol Geosci 5(1): 001-056. Copyright: © 2021 Kilias A. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

J Geol Geosci 56 Volume 5(1): 2021