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Triassic to Pleistocene sandstones of the Kyrenia Range, N Cyprus provide an exceptional repository of the erosional history of Anatolia. The Kyrenia Range features several different tectonic hypotheses concerning the Eastern Mediterranean region, which are tested here using a combination of new and recently published detrital zircon geochronology, zircon trace-element data and hafnium isotopic data. Minimum detrital zircon ages refine the ages of several formations in the Kyrenia Range. The new data also provide insights into sediment provenance including far-removed sources of Upper Paleozoic zircons, within-plate versus subduction-related sources (e.g., rift; oceanic/continental arc/ophiolite) and Neogene collision-related magmatism. Facies and paleocurrent data indicate a major switch in clastic sediment input from generally southwards to westwards during the Oligocene, which was mainly controlled by the collision of the Arabian promontory with Anatolia, leaving the S Neotethys as an isolated deep-water basin. The U-Pb zircon age profiles indicate a prominent Late Neoproterozoic population, together with Carboniferous, Permian, Late Cretaceous and Miocene-aged clusters. Pan-African and Grenvillian-aged zircons were ultimately derived from Cadomian continental basement. Basement that rifted from Gondwana during the Triassic later became sources of detritus within Anatolia to the north. Devonian-Carboniferous zircons were originally supplied by active continental margin magmatism in southern Eurasia (Pontides) or northern Gondwana (Afyon zone of the Anatolides). The proposed explanation is that detrital zircons were sequentially recycled, first to Upper Carboniferous-earliest Permian turbidites (within the Afyon zone to the east), later to Mid-Upper Triassic alluvium and turbidites (within the Taurides to the south), and finally to Triassic-Paleogene clastic sediments as now preserved in the Kyrenia Range. Upper Cretaceous zircons were derived from continental arc granitoids, oceanic arc and/or ophiolitic rocks and related metamorphic rocks, generally to the north of the Kyrenia Range. Paleogene zircons mainly represent late-stage continental margin arc magmatism in SE Turkey. During the Oligocene, the switch from mainly southward sediment supply to mainly westward sediment supply represents dominant input from the S Neotethyan suture zone in SE Turkey. Miocene zircons were mainly derived from post-collisional volcanics in SE Turkey. Paleoriver drainage systems in central/southeast Anatolia largely existed by the Late Miocene in response to collision-related surface uplift, in turn strongly influencing Miocene-Pleistocene zircon provenance in sub-basins within and adjacent to the Kyrenia Range. The combined zircon data, together with assembled geological evidence, are used to discuss three contrasting tectonic hypotheses for the early Mesozoic-Eocene setting of the Kyrenia Range: (1) locally, in the easternmost Mediterranean (i.e., preferred interpretation); (2) far to the south, on the N African passive margin, and (3) far to the north, along (or near) the Eurasian margin. Overall, the present study exemplifies the diversity and complexity of clastic sediment sources within a developing orogen, with implications for some other regions. • Detrital zircon U-Pb and related analyses indicate the erosional history of S Anatolia. • The combined data indicate a switch from N to E sources related to Neogene collision. • The zircon and related data support tectonic development along N margin of S Neotethys. [ABSTRACT FROM AUTHOR]

We focus on an active continental margin related to northwards subduction during the Eocene in which sedimentary melange (‘olistostromes’) forms a key component. Maastrichtian – Early Eocene deep-marine carbonates and volcanic rocks pass gradationally upwards into a thick succession (<800 m) of gravity deposits, exposed in several thrust sheets. The lowest levels are mainly siliciclastic turbidites and debris-flow deposits. Interbedded marls contain Middle Eocene planktonic/benthic foraminifera and calcareous nannofossils. Sandstones include abundant ophiolite-derived grains. The higher levels are chaotic debris-flow deposits that include exotic blocks of Late Palaeozoic – Mesozoic neritic limestone and dismembered ophiolite-related rocks. A thinner sequence (<200 m) in one area contains abundant redeposited Paleogene pelagic limestone and basalt. Chemical analysis of basaltic clasts shows that some are subduction influenced. Basaltic clasts from unconformably overlying alluvial conglomerates (Late Eocene – Oligocene) indicate derivation from a supra-subduction zone ophiolite, including boninites. Taking account of regional comparisons, the sedimentary melange is interpreted to have formed within a flexurally controlled foredeep, floored by continental crust. Gravity flows including large limestone blocks, multiple debris flows and turbidites were emplaced, followed by southwards thrust imbrication. The emplacement was possibly triggered by the final closure of an oceanic basin to the north (Alanya Ocean). Further convergence between the African and Eurasian plates was accommodated by northwards subduction beneath the Kyrenia active continental margin. Subduction zone rollback may have triggered collapse of the active continental margin. Non-marine to shallow-marine alluvial fans prograded southwards during Late Eocene – Oligocene time, marking the base of a renewed depositional cycle that lasted until latest Miocene time. [ABSTRACT FROM PUBLISHER]

Abstract: During Late Palaeozoic time a wide ocean, known as Palaeotethys, separated the future Eurasian and African continents. This ocean closed in Europe in the west during the Variscan orogeny, whereas in Asia further east it remained open and evolved into the Mesozoic Tethys, only finally closing during Late Cretaceous–Early Cenozoic. Three Upper Palaeozoic lithological assemblages, the Chios Melange (on the Aegean Greek island), the Karaburun Melange (westernmost Aegean Turkey) and the Teke Dere Unit (Lycian Nappes, SW Turkey) provide critical information concerning sedimentary and tectonic processes during closure of Palaeotethys. The Chios and Karaburun melanges in the west are mainly terrigenous turbidites with blocks and dismembered sheets of Silurian–Upper Carboniferous platform carbonate rocks (shallow-water and slope facies) and poorly dated volcanic rocks. The Teke Dere Unit to the southeast begins with alkaline, within-plate-type volcanics, depositionally overlain by Upper Carboniferous shallow-water carbonates. This intact succession is overlain by a tectonic slice complex comprising sandstone turbidites that are intersliced with shallow-water, slope and deep-sea sediments (locally dated as Early Carboniferous). Sandstone petrography and published detrital mineral dating imply derivation from units affected by the Panafrican (Cadomian) and Variscan orogenies. All three units are interpreted as parts of subduction complexes in which pervasive shear zones separate component parts. Silurian–Lower Carboniferous black cherts (lydites) and slope carbonates accreted in a subduction trench where sandstone turbidites accumulated. Some blocks retain primary depositional contacts, showing that gravitational processes contributed to formation of the melange. Detached blocks of Upper Palaeozoic shallow-water carbonates (e.g. Chios) are commonly mantled by conglomerates, which include water-worn clasts of black chert. The carbonate blocks are restored as one, or several, carbonate platforms that collided with an active margin, fragmenting into elongate blocks that slid into a subduction trench. This material was tectonically accreted at shallow levels within a subduction complex, resulting in layer-parallel extension, shearing and slicing. The accretion mainly took place during Late Carboniferous time. Alternative sedimentary-tectonic models are considered in which the timing and extent of closure of Palaeotethys differ, and in which subduction was either northwards towards Eurasia, or southwards towards Gondwana (or both). Terrane displacement is also an option. A similar (but metamorphosed) accretionary unit, the Konya Complex, occurs hundreds of kilometres further east. All of these units appear to have been assembled along the northern margin of Gondwana by Permian time, followed by deposition of overlying Tauride-type carbonate platforms. Northward subduction of Palaeotethys beneath Eurasia is commonly proposed. However, the accretionary units studied here are more easily explained by southward subduction towards Gondwana. Palaeotethys was possibly consumed by long-lived (Late Palaeozoic) northward subduction beneath Eurasia, coupled with more short-lived (Late Carboniferous) southward subduction near Gondwana, during or soon after closure of Palaeotethys in the Balkan region to the west. [Copyright &y& Elsevier]