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Rift basins in mountain belts shed light on the palaeogeography and tectonic development of adjacent sutured ocean basins, as for the Antalya Complex in the S Neotethys region. Based on literature review, supplemented by multidisciplinary new data, the Antalya Complex in this area represents an Upper Permian-Triassic rift basin and subsequent Jurassic-Cretaceous passive margin that encompasses a marginal shallow-water carbonate platform, slope facies and deeper water axial pelagic sediments and basaltic volcanics. The rift basin was bordered to the north by the Tauride Carbonate Platform, and to the south by the metamorphic Alanya Massif farther south. The S Neotethys was located further south, adjacent to N Africa. The evidence comes from a critical but little known E-W trending segment of the Antalya Complex (Antalya Nappes) in the east of the regional Isparta Angle (an orocline), known as the Güzelsu Corridor. To the south of the Tauride Carbonate Platform, the Güzelsu Corridor exposes three tectonic units within the Antalya Complex of Early Palaeozoic-Late Cretaceous age. The Lower Unit represents the proximal-distal slope of the Tauride platform. The Middle Unit preserves U. Permian-U. Cretaceous axial rift and passive margin settings. The Upper Unit (Gündoğmuş, Kavzandağ and Katrandağ thrust sheets) documents L. Palaeozoic pre-rift sediments, unconformably overlain by Permian-Triassic syn-rift units and a post-rift Jurassic-Cretaceous carbonate platform. Geochemical data highlight the rift-related setting of Upper Permian and Upper Triassic basaltic rocks in both the Middle and Upper Units. Radiolarian biochronology shows that the Middle Unit includes radiolarites of Late Triassic to Late Cretaceous (Campanian) age. Calcareous microfossil data shed light on facies development within the Antalya Complex and along the southern margin of the Tauride Carbonate Platform. Sedimentological and petrographic evidence help indicate depositional environments and processes. Structural data shed light on the emplacement of the Antalya Complex and its relation to the metamorphic Alanya Massif. Comparisons with counterparts of the Antalya Complex around the periphery of the Isparta Angle provide a regional palaeogeographic context. The Antalya Complex in the study area began to rift during the Late Permian, with initial localised alkaline basaltic volcanism. Further rifting (pulsed) and deepening took place during the Early to Middle Triassic. More extensive alkaline volcanics erupted during the Late Triassic (Carnian), coupled with terrigenous turbidites (Mid-Late Triassic), culminating in continental break-up to form the S Neotethys regionally (Carnian-Norian). Accumulation below the carbonate compensation depth took place within the deep-water rift basin during Jurassic-Late Cretaceous. Related to Late Cretaceous subduction, the Alanya microcontinent subducted northwards beneath the Antalya rift and the Tauride Carbonate Platform to the north. Initial collision dissected the rift and its margins into the three major tectonic units. Polymictic debris flows (olistostromes) were emplaced onto the southern margin of the Tauride platform during the latest Cretaceous (Campanian-Maastrichtian). Following partial exhumation, the Alanya Massif was thrust northwards, shedding metamorphic debris onto the adjacent Tauride platform (Early-Middle Eocene). Post-suture tightening (e.g., transcurrent faulting) occurred prior to Miocene transgression. The regional Eocene deformation was probably driven by final closure of Neotethyan ocean farther north. [Display omitted] • The Antalya Complex (Güzelsu Corridor, S Turkey) is reinterpreted as a marginal rift. • The marginal rift was bordered by satellite platforms with Neotethys to the south, • New geochemical data from Permian basalts indicate initial rifting. • Deep-water siliceous sedimentation is dated as Late Triassic-Late Cretaceous. • Initial Upper Cretaceous and final Palaeocene-Eocene emplacement took place. [ABSTRACT FROM AUTHOR]

Regionally developed late Cretaceous subduction-related magmatism in the eastern Mediterranean records progressive closure of the Southern Neotethys. In western Cyprus, the late Cretaceous (c. 90 Ma) Troodos ophiolite is depositionally overlain by volcaniclastic sandstones (up to 750 m thick) that are dominated by redeposited pyroclastic fallout, interbedded with both non-calcareous and calcareous radiolarian-bearing mudstones. The sands were mainly deposited by channelised mass-flow processes and to a lesser extent by turbidity currents in a deep-water forearc basin. The succession was folded and locally thrust-deformed related to latest Cretaceous emplacement of adjacent Mesozoic continental margin and oceanic units (Mamonia Complex). SIMS U-Pb analysis of euhedral to subhedral magmatic zircon crystals yielded a weighted mean 206Pb/238U age of 80.1 ± 1.1 Ma (Campanian). Sandstone petrography including compositional framework (Q 12 F 21 L 67) suggests sediment supply from a volcanic arc. Subordinate continentally-derived detritus suggests a continental margin arc setting for the mafic to felsic fallout ash. SIMS analysis of little-altered volcanic glass indicates high Th/Nb and Th/La ratios that suggest the involvement of continental crust and/or subducted terrigenous sediments in magma genesis. Whole-rock chondrite-normalised REE patterns have comparable trends to modern and ancient forearc basin volcaniclastic sands and sandstones (e.g., northwest Pacific region). Trace element chemistry, although scattered towards the continental island arc fields on some geochemical diagrams (e.g., Th-Sc-Zr), mainly suggests an oceanic island arc source for the Kannaviou Formation sandstones, with variable enrichments in V-Cr-Ni-Sc, depletion in Nb-Ta, and relatively low trace element ratios (e.g., La/Co, Th/Co, La/Sc, Th/Sc). An explanation for this apparent discrepancy is that the volcaniclastic sandstones were derived from a relatively primitive arc constructed on previously depleted, rifted (thinned) Neotethyan continental crust. The inferred continental margin arc developed during early-stage northward subduction of the Southern Neotethys beneath a Tauride microcontinent to the north. Large volumes of volcanic ash were derived from continental margin arc volcanism, probably in the vicinity of the Kyrenia Range in northern Cyprus. [ABSTRACT FROM AUTHOR]

Abstract: The southern margin of Eurasia, from the Balkan region eastwards, is widely envisaged as an active continental margin related to northward subduction, at least during Late Carboniferous–Early Cenozoic time. By contrast, the Late Palaeozoic setting of the southern (Gondwana) margin was previously interpreted as an intra-continental marginal basin related to southward subduction beneath the northern margin of Gondwana, or as part of a forearc complex (e.g. forearc basin) related to northward subduction beneath Eurasia. Palaeotethyan evolution is recorded in the Konya Complex (new name), an assemblage of Palaeozoic (Silurian-Carboniferous) meta-sedimentary and meta-igneous rocks that is exposed beneath metamorphosed Upper Permian–Mesozoic shelf-type sediments in central southern Turkey to the north of the Tauride Mountains. The Konya Complex is dominated by large thrust slices of mainly Devonian shallow-water platform carbonates (Bozdağ unit). There is also a melange that is made up of lenticular sheets and blocks of mainly Lower Carboniferous shallow-water limestones, Silurian–Devonian black chert (lydite), pelagic limestones and rare blocks of mid-ocean ridge-type and within plate-type basaltic rocks. The blocks are set in a mainly terrigenous-derived siliciclastic matrix, locally including siliceous tuff. The matrix is interpreted as mainly deep-water turbidites and debris-flow deposits. An overlying, intact volcanic-sedimentary sequence includes chemically enriched extrusives (e.g. trachyandesites) that also exhibit a negative Nb anomaly, suggesting a subduction influence. Dykes crosscutting the carbonate platform units are relatively depleted and also show a subduction influence. Shallow-marine carbonates and terrigenous quartzose sediments of mainly Late Permian age are exposed above the Konya Complex in the west of the area. In contrast, Triassic non-marine, to shallow-marine, clastic sediments unconformably overlie the Konya Complex in the east of the area. Both the Permian and the Triassic sediments pass upwards without a break into a Middle Triassic–Upper Cretaceous platform carbonate succession, which was overthrust by accretionary melange and ophiolites during latest Cretaceous time. The Mesozoic carbonate platform and the underlying Konya Complex experienced polyphase deformation and partial high-temperature/low-pressure metamorphism related to Alpine (Late Cretaceous–Early Cenozoic) closure of Tethys. Comparison of Tauride and Pontide units suggests the deformed Konya Complex Upper Palaeozoic carbonate platform has Gondwanan affinities. We also compare the Complex with other Upper Palaeozoic units in southern Turkey, including the Tekedere unit (Lycian Nappes) and the Karaburun and Chios melanges. All of these units are interpreted to have formed by subduction/accretion processes. Alternative possible settings involve northward subduction, southward subduction, or terrane displacement (strike-slip). Northward subduction beneath Eurasia requires collisional assembly with Gondwana, possibly during the latest Triassic “Cimmerian orogeny” for which there is little evidence. A southward-dipping subduction zone would need to be located some distance outboard of the Gondwana margin as there is little evidence of Upper Palaeozoic arc magmatism in the Tauride platform. Emplacement as an exotic terrane, probably derived from further west in the Balkan region is also possible. [Copyright &y& Elsevier]

Late Cretaceous felsic and latest Cretaceous-Paleogene basaltic volcanic rocks are exposed throughout the Kyrenia Range, N Cyprus. Field mapping of the key, well-exposed western range indicates that the felsic volcanics mainly crop out in the southerly, frontal part of the range, separated from the latest Cretaceous-Paleogene basaltic volcanics farther north by a thrust. New U-Pb zircon dating of the felsic volcanics indicates a primary age of c. 74.0 Ma (Late Campanian). The felsic volcanics are characterised by evolved compositions that were probably generated in an extensional subduction-related setting. Their relatively low Nb and Y but high Rb concentrations, together with characteristic Th/Ta ratios (6–20), suggest a mature continental arc setting. The latest Cretaceous-Paleogene basaltic volcanics have mainly within-plate chemical characteristics (in the east), although some have a subordinate subduction influence; e.g. negative Nb (in the west). Sr-Nd-Hf isotopic signatures (i.e. high positive εNd(t) and εHf(t) values) suggest derivation of the basalts from several OIB-like mantle sources, with probable involvement of a crustal (recycled) component (i.e. elevated Nb/Y ratios). Comparisons with SE Turkey, where Late Cretaceous arc-related granitic rocks are widely developed, suggest that the Kyrenia Range igneous rocks may have originated to the south of the Alanya metamorphic massif (N of Cyprus) and correlative continental units in SE Turkey. The latest Cretaceous-Paleogene basaltic volcanics in N Cyprus and SE Turkey (Maden Complex) are interpreted to represent incipient marginal basin formation, possibly in an oblique-convergent setting, prior to Miocene suturing with Arabia. In the light of alternatives, we infer genesis of the N Cyprus Late Cretaceous and Paleogene volcanic rocks related to stages in the development of the northerly active continental margin of the Southern Neotethys. • Felsic volcanics erupted at c. 74 Ma in an active continental margin arc setting. • Some within-plate basalts (c. dated at 70–45 Ma) were affected by subduction. • The basalts are interpreted to represent incipient marginal basin formation. • The volcanism provides new evidence of subduction in the E Mediterranean region. • Northward subduction is supported by coeval arc magmatism in SE Turkey. [ABSTRACT FROM AUTHOR]

Abstract: New structural data are presented and interpreted for the Cretaceous Hatay ophiolite, which was emplaced onto the Arabian continental margin during latest Cretaceous (Maastrichtian) time. Although lacking a preserved metamorphic sole, a thick serpentinitic basal shear zone provides evidence of emplacement kinematics, whilst structures developed in an extensive Cenozoic sedimentary cover help to constrain the nature of post-emplacement deformation. Combining field structural measurements with palaeostress analyses enables several discrete structural events to be recognised, of which three appear to pre-date the Cenozoic sedimentary cover. The earliest event involved extension parallel to the ophiolitic sheeted dyke complex and relates to oceanic spreading whereas the second and the third events relate to compression and strike-slip during intra-oceanic displacement, or emplacement of the ophiolite onto the Arabian continental margin. Some structures at the base of or within the ophiolite that were previously attributed to sea-floor spreading processes (e.g. “oceanic detachment faults”) are more likely to have formed during subsequent ophiolite displacement/emplacement and post-emplacement formation of the regional Hatay Graben. [Copyright &y& Elsevier]