scholarly journals Formation of a Composite Albian–Eocene Orogenic Wedge in the Inner Western Carpathians: P–T Estimates and 40Ar/39Ar Geochronology from Structural Units

Minerals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 988
Author(s):  
Marián Putiš ◽  
Ondrej Nemec ◽  
Martin Danišík ◽  
Fred Jourdan ◽  
Ján Soták ◽  
...  
Keyword(s):  
Evolutionary Model ◽  
White Mica ◽  
Western Carpathians ◽  
Low Grade ◽  
Accretionary Wedge ◽  
Structural Units ◽  
Upper Carboniferous ◽  
The North ◽  
Orogenic Wedge ◽  
Pieniny Klippen Belt

The composite Albian–Eocene orogenic wedge of the northern part of the Inner Western Carpathians (IWC) comprises the European Variscan basement with the Upper Carboniferous–Triassic cover and the Jurassic to Upper Cretaceous sedimentary successions of a large oceanic–continental Atlantic (Alpine) Tethys basin system. This paper presents an updated evolutionary model for principal structural units of the orogenic wedge (i.e., Fatricum, Tatricum and Infratatricum) based on new and published white mica 40Ar/39Ar geochronology and P–T estimates by Perple_X modeling and geothermobarometry. The north-directed Cretaceous collision led to closure of the Jurassic–Early Cretaceous basins, and incorporation of their sedimentary infill and a thinned basement into the Albian–Cenomanian/Turonian accretionary wedge. During this compressional D1 stage, the subautochthonous Fatric structural units, including the present-day higher Infratatric nappes, achieved the metamorphic conditions of ca. 250–400 °C and 400–700 MPa. The collapse of the Albian–Cenomanian/Turonian wedge and contemporary southward Penninic oceanic subduction enhanced the extensional exhumation of the low-grade metamorphosed structural complexes (D2 stage) and the opening of a fore-arc basin. This basin hemipelagic Coniacian–Campanian Couches-Rouges type marls (C.R.) spread from the northern Tatric edge, throughout the Infratatric Belice Basin, up to the peri-Pieniny Klippen Belt Kysuca Basin, thus tracing the south-Penninic subduction. The ceasing subduction switched to the compressional regime recorded in the trench-like Belice “flysch” trough formation and the lower anchi-metamorphism of the C.R. at ca. 75–65 Ma (D3 stage). The Belice trough closure was followed by the thrusting of the exhumed low-grade metamorphosed higher Infratatric complexes and the anchi-metamorphosed C.R. over the frontal unmetamorphosed to lowest anchi-metamorphosed Upper Campanian–Maastrichtian “flysch” sediments at ca. 65–50 Ma (D4 stage). Phengite from the Infratatric marble sample SRB-1 and meta-marl sample HC-12 produced apparent 40Ar/39Ar step ages clustered around 90 Ma. A mixture interpretation of this age is consistent with the presence of an older metamorphic Ph1 related to the burial (D1) within the Albian–Cenomanian/Turonian accretionary wedge. On the contrary, a younger Ph2 is closely related to the late- to post-Campanian (D3) thrust fault formation over the C.R. Celadonite-enriched muscovite from the subautochthonous Fatric Zobor Nappe meta-quartzite sample ZI-3 yielded a mini-plateau age of 62.21 ± 0.31 Ma which coincides with the closing of the Infratatric foreland Belice “flysch” trough, the accretion of the Infratatricum to the Tatricum, and the formation of the rear subautochthonous Fatricum bivergent structure in the Eocene orogenic wedge.

scholarly journals Structural pattern and emplacement mechanisms of the Krížna cover nappe (Central Western Carpathians)

2012 ◽  
Vol 63 (1) ◽  
pp. 13-32 ◽  
Author(s):  
Roberta Prokešová ◽  
Dušan Plašienka ◽  
Rastislav Milovský
Keyword(s):  
Driving Forces ◽  
Structural Evolution ◽  
Evolutionary Model ◽  
Structural Data ◽  
Western Carpathians ◽  
Low Grade ◽  
Structural Pattern ◽  
Thrust Tectonics ◽  
Central Western Carpathians ◽  
Nappe Emplacement

Structural pattern and emplacement mechanisms of the Krížna cover nappe (Central Western Carpathians)The Central Western Carpathians are characterized by both the thick- and thin-skinned thrust tectonics that originated during the Cretaceous. The Krížna Unit (Fatric Superunit) with a thickness of only a few km is the most widespread cover nappe system that completely overthrusts the Tatric basement/cover superunit over an area of about 12 thousands square km. In searching for a reliable model of its origin and emplacement, we have collected structural data throughout the nappe body from its hinterland backstop (Veporic Superunit) to its frontal parts. Fluid inclusion (FI) data from carbonate cataclastic rocks occurring at the nappe sole provided useful information about the p-T conditions during the nappe transport. The crucial phenomena considered for formulation of our evolutionary model are: (1) the nappe was derived from a broad rifted basinal area bounded by elevated domains; (2) the nappe body is composed of alternating, rheologically very variable sedimentary rock complexes, hence creating a mechanically stratified multilayer; (3) presence of soft strata serving as décollement horizons; (4) stress and strain gradients increasing towards the backstop; (5) progressive internal deformation at very low-grade conditions partitioned into several deformation stages reflecting varying external constraints for the nappe movement; (6) a very weak nappe sole formed by cataclasites indicating fluid-assisted nappe transport during all stages; (7) injection of hot overpressured fluids from external sources (deformed basement units) facilitating frontal ramp overthrusting under supralithostatic conditions. It was found that no simple mechanical model can be applied, but that all known principal emplacement mechanisms and driving forces temporarily participated in progressive structural evolution of the nappe. The rear compression operated during the early stages, when the sedimentary succession was detached, shortened and transported over the frontal ramp. Subsequently, gravity spreading and gliding governed the final nappe emplacement over the unconstrained basinal foreland.

scholarly journals GEOLÓGIA A TEKTONIKA STYČNEJ OBLASTI CENTRÁLNYCH A EXTERNÝCH KARPÁT NA ZÁPADNOM SLOVENSKU – PREHĽAD NOVÝCH VÝSLEDKOV A KONCEPCIÍ

2016 ◽  
Vol 22 (1-2) ◽  
Author(s):  
Dušan Plašienka
Keyword(s):  
Tectonic Evolution ◽  
Lower Plate ◽  
Accretionary Wedge ◽  
Accretionary Complex ◽  
The South ◽  
Sedimentary Record ◽  
Clastic Sediments ◽  
Orogenic Wedge ◽  
Pieniny Klippen Belt

New data gathered in the Pieniny Klippen Belt (PKB) and adjacent zones along the Central–External Carpathians boundary in western Slovakia allow for a formulation of an updated model of its structure and tectonic evolution. In general, these zones evolved as an accretionary complex in front of the prograding Central Western Carpathian orogenic wedge during the latest Cretaceous to Paleogene. Step-by-step forward accretion of Oravic units of the PKB (Šariš, Subpieniny, Pieniny) with piggyback frontal elements of the Fatric units (Drietoma, Manín, Klape) was followed by incorporation of the External Carpathian Biele Karpaty and Magura units and brought about transfer of the Oravic elements from the wedge tip to its rear. The wedge growth was accompanied by steepening of the PKB structures up to final overturning and backthrusting to the south in places. By this process, the PKB were ultimately placed in the centre or southern limb of an asymmetric fan-wise accretionary wedge, i.e. in a backstop position between the wedge and rigid Central Carpathian block. Consequently, the original fold-and-thrust structures of the PKB were modifi ed or largely obliterated by superimposed out-of-sequence thrusting, transpressional and transtensional deformation. In addition to a rather poor brittle structural record that is mostly related to younger post-thrusting deformation, these processes are nicely registered by synorogenic clastic sediments in both the trench-foredeep basins in the lower plate of the convergent system (Oravic units) and in the piggyback, wedge-top basins above the deformed wedge (Gosau-type basins). Sedimentary record in the wedge-top area is diff erentiated into several transgression/regression cycles that are interpreted in terms of the critical wedge theory.

scholarly journals Annales Societatis Geologorum Poloniae Journal Content Search Browse By Issue By Author By Title Other Journals User Username Password Home About Login Register Search Current Archives Submissions In press Home > Archives > Vol 85, No 1 (2015) Vol 85, No 1 (2015) Table of Contents Preface Eighty-fifth Anniversary of the Birth of Professor Krzysztof Birkenmajer Przemysław Gedl Annales Societatis Geologorum Poloniae Vol 85, No 1 (2015) 3-19, doi: 10.14241/asgp.2015.001 PDF Articles Aptian age of the “spotted limestone” (Pieniny Limestone Formation) in Grajcarek Stream (Pieniny Klippen Belt, Poland) Andrzej Pszczółkowski Annales Societatis Geologorum Poloniae Vol 85, No 1 (2015) 21-42, doi: 10.14241/asgp.2014.001 PDF Evolution of Late Cretaceous–Palaeogene synorogenic basins in the Pieniny Klippen Belt and adjacent zones (Western Carpathians, Slovakia): tectonic controls over a growing orogenic wedge Dušan Plašienka, Ján Soták Annales Societatis Geologorum Poloniae Vol 85, No 1 (2015) 43-76, doi: 10.14241/asgp.2015.005 PDF Neogene calc-alkaline intrusive magmatism of post-collisional origin along the Outer Carpathians: a comparative study of the Pieniny Mountains and adjacent areas Zoltán Pécskay, Katalin Gméling, Ferenc Molnár, Zsolt Benkó Annales Societatis Geologorum Poloniae Vol 85, No 1 (2015) 77-89, doi: 10.14241/asgp.2014.006 PDF Early?–Middle Jurassic dinoflagellate cysts and foraminifera from the dark shale of the Pieniny Klippen Belt between Jarabina and Litmanová (Slovakia): age and palaeoenvironment

2015 ◽  
Author(s):  
Przemysław Gedl ◽  
Štefan Józsa
Keyword(s):  
Comparative Study ◽  
Late Cretaceous ◽  
Middle Jurassic ◽  
Western Carpathians ◽  
Calc Alkaline ◽  
Content Search ◽  
Orogenic Wedge ◽  
Outer Carpathians ◽  
Pieniny Klippen Belt ◽  
Journal Content

scholarly journals Linkage of the Manín and Klape units with the Pieniny Klippen Belt and Central Western Carpathians: balancing the ambiguity

2019 ◽  
Vol 70 (1) ◽  
pp. 35-61 ◽  
Author(s):  
Dušan Plašienka
Keyword(s):  
Sedimentary Cover ◽  
Structural Data ◽  
Western Carpathians ◽  
Stress System ◽  
Accretionary Wedge ◽  
Short Term ◽  
Fault Structures ◽  
Pieniny Klippen Belt ◽  
Central Western Carpathians ◽  
Bottom To Top

Abstract The paper deals with the structure and evolution of the Pieniny Klippen Belt in its classic area in western Slovakia. The so-called Peri-Klippen Zone provides a transition from the Pieniny Klippen Belt s.s. built up by Jurassic to Eocene Oravic units (Šariš, Subpieniny and Pieniny from bottom to top) to the outer margin of the Central Western Carpathians composed of Triassic to mid-Cretaceous successions of the Fatric and Hronic cover nappe systems. The Peri-Klippen Zone attains a considerable width of 15 km in the Middle Váh River Valley, where it is composed of the supposedly Fatric Manín, Klape and Drietoma units, as well as their post-emplacement, Gosau-type sedimentary cover. All these units are tightly folded and imbricated. The complex sedimentary and structural rock records indicate the late Turonian emplacement of the frontal Fatric nappes in a position adjacent to or above the inner Oravic elements, whereby they became constituents of an accretionary wedge developing in response of subduction of the South Penninic– Vahic oceanic realm separating the Central Western Carpathians and the Oravic domain. Evolution of the wedge-top Gosau depressions and the trench-foredeep basins of the foreland Oravic area exhibit close mutual relationships controlled by the wedge dynamics. The kinematic and palaeostress analyses of fold and fault structures revealed only one dominating stress system coeval with development of the accretionary wedge, which is characterized by the generally NW–SE oriented main compression axis operating in a pure compressional to dextral transpressional regime, interrupted by short-term extensional events related to the wedge collapse stages. Younger, Miocene to Quaternary palaeostress fields correspond to those widely recorded in the entire Western Carpathians. Relying on the regional tectonostratigraphic and structural data, the problematic issues of the palaeogeographic settings of the Manín and Klape units, presumably affiliated with the Fatric cover nappe system, and of the provenance of numerous olistoliths occurring at different stratigraphic levels are then discussed in a broader context.

scholarly journals Provenance of the detrital garnets and spinels from the Albian sediments of the Czorsztyn Unit (Pieniny Klippen Belt, Western Carpathians, Slovakia)

2009 ◽  
Vol 60 (6) ◽  
pp. 463-483 ◽  
Author(s):  
Roman Aubrecht ◽  
Štefan Méres ◽  
Milan Sýkora ◽  
Tomáš Mikuš
Keyword(s):  
Middle Jurassic ◽  
Alternative Interpretation ◽  
Heavy Mineral ◽  
Western Carpathians ◽  
Accretionary Wedge ◽  
Outer Western Carpathians ◽  
Pieniny Klippen Belt ◽  
Central Western Carpathians ◽  
Heavy Mineral Analysis ◽  
Back Arc

Provenance of the detrital garnets and spinels from the Albian sediments of the Czorsztyn Unit (Pieniny Klippen Belt, Western Carpathians, Slovakia)According to earlier concepts, the Czorsztyn Unit (Oravic Superunit, Pieniny Klippen Belt, Western Carpathians) sedimented on the isolated Czorsztyn Swell which existed in the Middle Jurassic-Late Cretaceous time in the realm of the Outer Western Carpathians. This paper brings new data providing an alternative interpretation of its Cretaceous evolution. They are based on heavy mineral analysis of the Upper Aptian/Lower Albian sediments of the Czorsztyn Unit. They rest upon a karstified surface after a Hauterivian-Aptian emersion and are represented by condensed, red marly organodetritic limestones with some terrigenous admixture (Chmielowa Formation). The heavy mineral spectrum is dominated by spinels, followed by garnet, with lesser amounts of zircon, rutile and tourmaline. The composition of the majority of the detrital garnets shows that they were derived from primary HP/UHP parental rocks which were recrystallized under granulite and amphibolite facies conditions. The garnets were most probably derived directly from the magmatic and metamorphic rocks of the Oravic basement, as the high-pyrope garnets are known to be abundant in Mesozoic sediments all over the Outer Western Carpathians. The presence of spinels is surprising. According to their chemistry, they were mostly derived from mid-oceanic ridge basalts (MORB) peridotites, supra-subduction zone peridotites (harzburgites) and transitional lherzolite/harzburgite types. Only a lesser amount of spinels was derived from volcanics of BABB composition (back-arc basin basalts). The presence of this ophiolitic detritus in the Czorsztyn Unit is difficult to explain. Ophiolitic detritus appeared in the Aptian/Albian time only in the units which were considered to be more distant, because they were situated at the boundary between the Central and the Outer Western Carpathians (Klape Unit, Tatric and Fatric domains). The hypothetical Exotic Ridge which represented an accretionary wedge in front of the overriding Western Carpathian internides was considered to be a source of the clastics. In previous paleogeographical reconstructions, the Czorsztyn Unit was situated north of the Pieniny Trough (considered to be one of the branches of the Penninic-Vahic Ocean). In the trough itself, the ophiolitic detritus appeared as late as in the Senonian and there was no way it could reach the Czorsztyn Swell which was considered to be an isolated elevation. The new results presented herein show that these reconstructions do not fit the obtained data and infer a possibility that the Czorsztyn sedimentary area was not isolated in the Cretaceous time and it was situated closer to the Central Carpathian units than previously thought. A new paleogeographical model of the evolution of the Pieniny Klippen Belt is presented in the paper: Oravic segment was derived from the Moldanubian Zone of the Bohemian Massif by the Middle Jurassic rifting which caused block tilting where most of the Oravic units were arranged north of the Czorsztyn Swell. The Oravic segment was situated in the lateral continuation of the Central and Inner Western Carpathians from which it was detached by later clockwise rotation. The Oravic segment was then laterally shifted in front of the Central Western Carpathians, together with remnants of the Meliatic suture zone which represented a source for the exotics to the Klape, Tatric, Fatric and Oravic units.

scholarly journals Structural evolution of the Turňa Unit constrained by fold and cleavage analyses and its consequences for the regional tectonic models of the Western Carpathians

2016 ◽  
Vol 67 (2) ◽  
pp. 179-195 ◽  
Author(s):  
Alexander Lačný ◽  
Dušan Plašienka ◽  
Rastislav Vojtko
Keyword(s):  
Large Scale ◽  
Structural Evolution ◽  
Lower Triassic ◽  
Geological Structure ◽  
Western Carpathians ◽  
Low Grade ◽  
Accretionary Wedge ◽  
Deformation Stage ◽  
Bedding Planes ◽  
Regional Tectonic

AbstractThe Turňa Unit (Turnaicum, Tornaicum) is one of the three nappe systems involved in the geological structure of the inner zones of the Western Carpathians. The unit is formed by a system of partial nappes and duplexes, which overlie the Meliata Unit s.l. and are overridden by the Silica Nappe. The Slovenská skala partial nappe in the investigated area includes clastic sediments of the mid-Carboniferous, Permian and Early Triassic age, followed by mostly deep-water Middle-Upper Triassic succession predominantly composed of carbonates. Structural analysis of cleavage planes and folds was carried out predominantly in the Lower Triassic Werfen Formation. The measured deformational structures are polygenetic and were principally formed in three successive deformation stages. The first deformation stage is represented by bedding-parallel, very low-grade metamorphic foliation that was related to nappe stacking and formation of the Mesozoic accretionary wedge during the latest Jurassic and earliest Cretaceous. The second deformation stage is represented by systems of open to closed, partly asymmetric folds with SW-NE oriented, steeply NW- or SE-dipping axial-plane cleavage. Regionally, the folded bedding planes are usually moderately SE-ward dipping, the NW-ward and subvertical dips are less common. The mesoscopic fold structures predominantly occur in the SW-NE trending anticlinal and synclinal hinge zones of large-scale folds. These structures evolved in a compressional tectonic regime with the NW-SE to N-S orientation of the maximum compressional axis. The third observed deformation stage was activated during ENE-WSW oriented shortening. This stage is chiefly represented by open, kink-type folds. Some inferences for regional structures and tectonic evolution of the area are discussed as well.

Significance of illite crystallinity and bo values of K-white mica in lowgrade metamorphic rocks, North Hill End Synclinorium, New South Wales, Australia

1985 ◽  
Vol 49 (352) ◽  
pp. 357-364 ◽  
Author(s):  
R. Offler ◽  
E. Prendergast
Keyword(s):  
Early Carboniferous ◽  
Geothermal Gradient ◽  
White Mica ◽  
Low Grade ◽  
Illite Crystallinity ◽  
The North ◽  
South Wales ◽  
The Mean ◽  
Two Populations

AbstractA study of low-grade metamorphism in late Silurian to early Carboniferous rocks in the North Hill End Synclinorium and adjacent anticlinoria has been made by the determination of illite crystallinity and bo values of K-white mica in eighty slates and phyllites. Illite crystallinity values vary from 0.40 Δ°2θ on the Molong Anticlinorium to 0.12 Δ°2θ within the axis of the synclinorium, suggesting anchizonal to epizonal metamorphic conditions. This is in agreement with previous observations on Ca-Al-hydrosilicate assemblages which indicated a change from prehnite-pumpellyite facies in the anticlinoria adjacent to the synclinorium to middle greenschist facies in the axis. Local variations in crystallinity are attributed to variation in ak+ in fluids migrating along cleavage zones.The mean bo value obtained from the pelites is 9.017 Å (σn = 0.008; n = 80) which is in close agreement with that obtained from part of the adjacent Capertee Anticlinorium (x̄ = 9.019 Å; σn = 0.007; n = 52). However, ‘t’ tests indicate that two bo populations are present in the synclinorium (x̄ = 9.019 and 9.022 Å), with the lower values concentrated in the southern portion of this structure. The two populations are considered to be the result of slightly different metamorphic conditions prevailing during the deformation of the rocks in the synclinorium. A higher geothermal gradient affecting rocks giving the lower bo values is attributed to the presence of granitoids at shallower depths than elsewhere in the synclinorium.

A basement culmination in the Scandinavian Caledonides formed by antiformal stacking (Bångonåive, northern Sweden)

1993 ◽  
Vol 130 (4) ◽  
pp. 471-482 ◽  
Author(s):  
R. O. Greiling ◽  
R. A. Gayer ◽  
M. B. Stephens
Keyword(s):  
Structural Information ◽  
Sedimentary Cover ◽  
Shear Zones ◽  
White Mica ◽  
Structural Level ◽  
Structural Units ◽  
The North ◽  
Thrust Tectonics ◽  
Shear Sense ◽  
Lift Off

AbstractThe Bångonåive basement culmination, a doubly plunging antiform trending SW-NE in its southern part and SSW-NNE in the north, is part of a major Caledonian antiform in north-central Scandinavia. Crystalline, Proterozoic basement rocks (mainly syenite) are unconformably overlain by a sedimentary cover including tillites at the base, passing up into arkoses, quartzites and shales, capped by black phyllites. This sequence is correlated with the Varangian to Cambrian succession of the Baltoscandian platform farther east. Detailed mapping revealed a succession of five basement-cover horses, which represent the accessible part of an antiformal stack exposed beneath the Middle and Upper Allochthons and taken here as the Lower Allochthon structural level.Caledonian deformation varies in intensity from penetrative near thrusts and in pelitic rocks to very weak in the more internal parts of the horses. A penetrative foliation is associated with the growth of white mica and rare biotite. This early fabric is overprinted by a mylonitic foliation related to localized shear zones, which separate the structural units within the Lower Allochthon. Stretching and mineral lineations trend WNW-ESE and related shear-sense criteria indicate transport (top) towards the ESE. Structural units (horses) are thrust into an antiformal stack and folded around the lowermost horse exposed, which is itself folded into an anticlinal lift-off fold. Towards the northeast, the antiformal stack is overprinted by a pop-up and an out-of-sequence thrust. The latter breached the roof of the Lower Allochthon and transported part of it over the Middle and Upper Allochthons. Further folds are associated with lateral and oblique ramps in the Lower Allochthon. These structures relate very well with the complex fold pattern previously observed in the higher structural units and thrust tectonics provides a straightforward genetic explanation for these folds. Therefore, earlier genetic models of the Bångonåive basement culmination as a simple imbrication of basement into higher units, as a buckling structure or as a gravitational dome structure are rejected here. The structural information, supported by gravimetric data, is consistent with an essentially flat regional detachment surface (2° dip) extending from the present external Caledonian margin to the base of the Bångonåive antiformal stack.

scholarly journals Origin and Age Determination of the Neotethys Meliata Basin Ophiolite Fragments in the Late Jurassic–Early Cretaceous Accretionary Wedge Mélange (Inner Western Carpathians, Slovakia)

Minerals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 652 ◽  
Author(s):  
Putiš ◽  
Soták ◽  
Li ◽  
Ondrejka ◽  
Li ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
Continental Margin ◽  
Deep Water ◽  
Late Jurassic ◽  
Age Determination ◽  
Evolutionary Model ◽  
Western Carpathians ◽  
Alkaline Basalt ◽  
Accretionary Wedge ◽  
Depleted Mantle

This study reports the Neotethyan Meliata Basin ophiolite fragments in the Late Jurassic–Early Cretaceous accretionary wedge mélange in the southern part of the Inner Western Carpathians (IWC). Here we present new lithostratigraphical, petrographical, geochemical, and geochronological data obtained from the mélange blocks used to reconstruct the Meliaticum paleotectonic zones in a tentative evolutionary model of this accretionary wedge. The Dobšiná mélange block continental margin carbonatic and siliciclastic sediments have calc-alkaline basalt intercalations. The basalt Concordia age dated to 245.5 ± 3.3 Ma by U–Pb SIMS on zircon most likely indicates the pre-oceanic advanced early Middle Triassic continental rifting stage. The evolving marginal oceanic crust is composed of Middle to Upper Triassic cherty shales to radiolarites. The detrital zircon U–Pb SIMS Concordia ages of 247 ± 4 Ma and 243 ± 4 Ma from a cherty shale, and the xenocryst zircon population Concordia age of 266 ± 3 Ma from a 0.5 m thick “normal” mid-ocean ridge (N-MOR) basalt layer in this cherty shale reveal the connection of the oceanic basin to the adjacent rifting continental margin. The chertified reddish limestone transition to radiolarite indicates syn-rift basin deepening. Upwards, regular alternating N-MOR basalts and radiolarites are often disturbed by peperite breccia horizons. The Nd isotope values of these basalts (εNd240 = 7–8) are consistent with their chondrite normalized rare earth element (REE) patterns and indicate a depleted mantle source. The Triassic ophiolitic suite also comprises rare ocean island (OI) basalts (εNd240 = 5) and serpentinized subduction unrelated peridotites. The Middle to Late Jurassic shortening and southward intra-oceanic and continental margin subduction at approximately 170–150 Ma enhanced the formation of the trench-like Jurassic flysch succession which preceded the closure of the Meliata Basin. The flysch sediments form a mélange matrix of olistolithic unsubducted, obducted, and MP–HP/LT metamorphosed exhumed blocks of the Triassic to Lower Jurassic successions. Blocks of peridotites, rodingites, blueschists, greenschists, rare amphibolites, deep-water shaly sediments and shallow- to deep-water carbonates are typical members of the mélange. The Meliatic accretionary wedge mélange nappe outliers were incorporated in the IWC orogenic wedge in the late Early Cretaceous according to metamorphic rutile U–Pb SIMS ages of 100 ± 10 Ma determined from a Jaklovce metabasalt.

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