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We present a map that correlates tectonic units between Alps and western Turkey accompanied by a text providing access to literature data, explaining the concepts used for defining the mapped tectonic units, and first-order paleogeographic inferences. Along-strike similarities and differences of the Alpine-Eastern Mediterranean orogenic system are discussed. The map allows (1) for superimposing additional information, such as e.g., post-tectonic sedimentary basins, manifestations of magmatic activity, onto a coherent tectonic framework and (2) for outlining the major features of the Alpine-Eastern Mediterranean orogen. Dinarides-Hellenides, Anatolides and Taurides are orogens of opposite subduction polarity and direction of major transport with respect to Alps and Carpathians, and polarity switches across the Mid-Hungarian fault zone. The Dinarides-Hellenides-Taurides (and Apennines) consist of nappes detached from the Greater Adriatic continental margin during Cretaceous and Cenozoic orogeny. Internal units form composite nappes that passively carry ophiolites obducted in the latest Jurassic–earliest Cretaceous or during the Late Cretaceous on top of the Greater Adriatic margin successions. The ophiolites on top of composite nappes do not represent oceanic sutures zones, but root in the suture zones of Neotethys that formed after obduction. Suturing between Greater Adria and the northern and eastern Neotethys margin occupied by the Tisza and Dacia mega-units and the Pontides occurred in the latest Cretaceous along the Sava-Izmir-Ankara-Erzincan suture zones. The Rhodopian orogen is interpreted as a deep-crustal nappe stack formed in tandem with the Carpatho-Balkanides fold-thrust belt, now exposed in a giant core complex exhumed in late Eocene to Miocene times from below the Carpatho-Balkan orogen and the Circum-Rhodope unit. Its tectonic position is similar to that of the Sakarya unit of the Pontides. We infer that the Rhodope nappe stack formed due to north-directed thrusting. Both Rhodopes and Pontides are suspected to preserve the westernmost relics of the suture zone of Paleotethys.

This study documents the Cenozoic to recent evolution of the Adria-Europe plate boundary zone, the Sava Zone, in the northern Dinarides. Late Cretaceous subduction of last remnants of Vardar oceanic lithosphere led to the formation of a suture, across which the upper plate Tisza-Dacia Mega-Unit (attached to Europe during the Early Cretaceous and therefore referred to as European Plate, for simplicity) was juxtaposed against the Adriaderived units of the Dinarides. The Dinarides reside in a lower plate position and include Vardar-derived ophiolites obducted in the Latest Jurassic. Late Cretaceous, largely siliciclastic sediments have been incorporated into an accretionary wedge that evolved during the initial stages of continent-continent collision. The structurally lowest parts of the presently exposed accretionary wedge underwent amphibolite grade metamorphism. Top-to-the-Sdirected senses of shear in mylonites and south-facing folding in low-grade phyllites are consistent with the assumption that the European plate overthrusted the Adriatic units. 39Ar/40Ar amphibole ages indicate cooling from peak metamorphic conditions at ca. 55 Ma. Plate convergence continued throughout the Paleogene and gave rise to foreland propagation, i.e. southwest-directed thrusting within the Dinarides. From the Late Oligocene onwards the Sava Zone underwent extension. Its early stages were accompanied by retrogression of peak-metamorphic mineral assemblages and footwall exhumation beneath a low-angle detachment. 39Ar/40Ar white mica cooling ages between 28 and 24 Ma date the initial stages of extensional unroofing. The low-angle detachment telescoped the metamorphic gradient, transposed an older metamorphic foliation and became in turn cut by late-stage brittle high-angle normal faults. S-type granitoids with 206Pb/238U zircon and 207Pb/235U monazite ages of 26.7 and 26.6 Ma were syn-tectonically emplaced and developed a solid-state foliation that formed under greenschist-facies conditions. Zircon and apatite fission track ages from both metamorphics and granitoids range between 21 and 14 Ma and indicate ongoing exhumation. Late-stage cooling is synchronous with the Ottnangian to Karpatian synrift phase of the Pannonian Basin. After the Pontian, the normal faults were inverted, creating the characteristic ‘inselberg’ morphology of the southwestern Pannonian Basin. At present, the area is governed by N-S compression and represents the seismically most active part of the Dinarides apart from the external-most thrusts in the Adriatic Sea.

The internal Dinarides of Former Yugoslavia are characterised by the widespread occurrence of ophiolites. Having formed part of the Vardar ocean, they were obducted onto the distal passive margin of the Adriatic platform in the Late Jurassic. Later, they were incorporated into the Late Cretaceous to Palaeogene SW-verging nappe stack of the Dinarides, where they occupy a structurally high position today. While there is general consensus about the (Late Jurassic) age of obduction of these ophiolites, recent investigations in the northernmost Dinarides of Bosnia-Hercegovina have revealed the existence of a mafic rock suite of Upper Cretaceous age in a yet more internal (i.e. more northerly) position of the Dinarides’ nappe stack. This mafic rock suite, exposed in the northern part of the Kozara Mountains (termed N Kozara from here on), very likely belongs to the “ Sava Zone” , a Mid-Cretaceous to Early Palaeogene accretionary prism, volcanic arc and back-arc basin that underwent Early Tertiary metamorphism and that remained open until collision between the Dinarides and the northerly adjacent Tisza block in the Mid-Eocene. Whether or not the mafic rocks of N Kozara truly represent ophiolites that could be regarded as a Cretaceous remnant of the Vardar ocean, is yet very improperly understood. Solving these questions, however, will improve timing constraints on the final closure of this domain and the subsequent collision with the Tisza block. It is therefore the aim of this study (a) to comprehend the structural position of the Kozara ophiolites with respect to the “ classic” Dinaric ophiolites, obducted in the Late Jurassic, and the northerly adjacent units within the Sava Zone, (b) to characterise their geodynamic setting using their geochemical signatures and (c) to obtain radiometric ages of the mafic rocks and biostratigraphic ages of associated sediments. Going from S to N, the massif of Kozara reveals the following succession of WNW-ESE-trending units. In the S, serpentinised lherzolithes and gabbros sit on top of a presumably Jurassic mélange formation, containing limestone olistolithes of Triassic age. Dolerites are found to be intersected by albite-rich felsic rocks. A Sm-Nd-age, obtained from a well-preserved olivine cumulate gabbro, yielded an age of 158 ± ; ; 8 Ma. This ophiolitic succession itself is unconformably covered by Palaeocene/Eocene Discocyclinae-bearing shallow-water limestones and subordinately shales that post-date the age of obduction. The mafic rocks of N Kozara are separated from the ones in the S by a 5 to 7 km wide belt of siliciclastic flysch of presumably Late Cretaceous to Palaeogene age. The mafic rocks of N Kozara, overlying the flysch, consist of basalts, dolerites and gabbros. Ultramafics are absent. Occasionally, basalts exhibit pillow-lava textures and are intercalated with red, pelagic limestones containing Globotruncanae that indicate an Early Campanian age (or, alternatively, Late Campanian to Early Maastrichtian. Gabbros and dolerites frequently reveal the growth of secondary, green amphibole on the expense of clinopyroxene, rendering these lithologies unsuitable for Sm-Nd-dating. Moreover, the N Kozara mafics are often intersected by Na- and K-rich felsic dikes. Geochemical analyses of mafic rocks from S and N Kozara show differences in both their major and trace element concentrations. Gabbros from the S show Mg-contents typical of primitive MORB. Basalts, dolerites and gabbros from N Kozara, on the other hand, exhibit significantly lower Mg-contents and enrichment of incompatible elements like Ti and P, suggesting a more differentiated or enriched magma source. Chondrite-normalised REE concentrations of samples from S Kozara (particularly gabbros) reveal a strong depletion of LREE and lesser depletion of HREE. Samples from N Kozara, in contrast, show enrichment of LREE over HREE. These features suggest an N-type MORB origin of the S Kozara samples, whereas N Kozara samples are more characteristic of an island-arc or transitional MORB setting with a low degree of partial melting. There is evidence that the mafic rock suites of S and N Kozara have been juxtaposed tectonically. This is indicated by basaltic pebbles from the separating flysch belt, which clearly bear the geochemical signature of the overlying N Kozara mafics. In agreement with published data we therefore invoke the possibility that the N Kozara mafics could represent a Late Cretaceous to Early Palaeogene (?) remnant of the Vardar ocean, which was juxtaposed against the “ classical” Dinaric ophiolites (obducted in the Late Jurassic) during the final closure of an oceanic domain within the Sava Zone. Future work will include the U-Pb-dating of zircons from highly differentiated gabbros and dolerites of N Kozara, as well as Nd- and Sr-isotope measurements on samples from both S and N Kozara. While the former should yield the first radiometric ages of the N Kozara mafic suite, the latter will allow characterising its mantle reservoir. Moreover, fission track analyses will be carried out in order to constrain the cooling history.