Alastair H. F. Robertson, 2000. "Mesozoic–Tertiary tectonic–sedimentary evolution of a south Tethyan oceanic basin and its margins in southern Turkey", Tectonics and Magmatism in Turkey and the Surrounding Area, Erdin Bozkurt, John A. Winchester, John D. A. Piper
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This paper focuses on the Mesozoic-Tertiary tectonic evolution of southern Turkey and offshore areas of the easternmost Mediterranean. The area is discussed and interpreted utilizing three segments from west to east. In the far west, the Lycian Nappes represent emplaced remnants of mainly Mesozoic rift, passive margin and oceanic units that formed within a northerly strand of the Mesozoic (i.e. Neotethyan) ocean. Further east, the Hoyran-Beyşehir-Hadim Nappes, likewise encompass sedimentary and igneous units that formed within a northerly Neotethyan oceanic basin, although lithologies, structure and timing of emplacement differ from the Lycian Nappes. Further east (Adana region), ophiolites and ophiolitic mélange also formed in a northerly oceanic basin and were thrust southwards over the regionally extensive Tauride carbonate platform initially in latest Cretaceous time (e.g. Pozanti-Karsanti Ophiolite).
By contrast, further south the regionally important Antalya Complex records northerly areas of a separate, contrasting southerly Neotethyan oceanic basin. This comprised a mosaic of carbonate platforms and interconnecting seaways, similar to the Caribbean region today. In particular, an ocean strand separated Tauride carbonate platforms to the west (Bey Dağlari) and east (e.g. Akseki Platform) within the Isparta Angle area. In the centre of southern coastal Turkey, the metamorphic Alanya Massif is interpreted as a Triassic rift basin bordered by two small platform units that was located along the northern margin of the southerly Neotethys which collapsed in latest Cretaceous and was finally emplaced in Early Tertiary time. Remnants of the southerly Neotethyan oceanic basin remain today in the non-emplaced continental margin of the Levant and North Africa, and neighbouring seafloor areas (e.g. Levant and Herodotus Basins).
In southern Turkey, emplaced Neotethyan units are unconformably overlain by a complex of mainly Miocene basins. These largely reflect the effects of southward directed crustal loading as convergence of Africa and Eurasia continued, although the basins were also influenced by an inferred more southerly subduction zone (near Cyprus). Further east, in southeastern Turkey, ophiolites, ophiolitic mélange and continental margin units were emplaced southwards onto the Arabian Margin, a promontory of North Africa in latest Cretaceous time. The south Neotethyan basin’s north margin experienced northward subduction, accretion, arc volcanism and ophiolite emplacement in Late Cretaceous time. The intervening southerly Neotethyan oceanic basin remained partly open in the Early Tertiary, finally closing by diachronous collision in Eocene-Oligocene time, followed by further convergence and overthrusting in the Miocene. The Eocene later stages of convergence were marked by renewed arc volcanism and extensive subduction accretion (e.g. Maden Complex). In the west, subduction remained active in Late Oligocene-Early Miocene time giving rise to sedimentary mélanges (olistostromes) of the Misis-Andirin Mountains (Adana region) as an accretionary wedge. By the Miocene the subduction zone accommodating Africa-Eurasia convergence had been relocated to its present position south of Cyprus. Areas behind this subduction experienced crustal extension (e.g. Antalya and Adana-Cilicia Basins) from the Late Miocene onwards. After onset of westward ‘tectonic escape’ of the Turkish Plate in the Early Pliocene, southeastern Turkey was transected by the South Anatolian Transform Fault. Strike-slip was dissipated though the Kyrenia-Misis Lineament into Cyprus. Today, southeastern Turkey records a post-collisional setting, whereas areas to the west experience incipient collision of the African and Turkish Plates.
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Tectonics and Magmatism in Turkey and the Surrounding Area
This volume contains 23 papers from a range of international contributors, describing recent research into the tectonics and magmatism of Turkey and its surroundings. This region is sited at the collision zone between Eurasia and Afro-Arabia and, as such, provides an extraordinarily complete and well-exposed record of the staged tectonic evolution of this sector of the Alpine-Himalayan orogen. The geological history of this area involves separation of continental fragments from the margin of Gondwana, their migration across the Tethyan oceans, the subsequent closure of these oceans and, finally, the development of the neotectonic regime, which continues to evolve to the present day. Such a comprehensive record is relevant to the understanding of collisional zones worldwide.
The volume is divided into five sections: Tethyan evolution, Neotethyan ophiolites, post-Tethyan basin evolution, neotectonics and igneous activity. The first two sections deal with Tethyan oceans, whose growth and subsequent closure dominated the geodynamic framework in the Mesozoic and Cenozoic. The subsequent sections deal with more recent geological developments from the Balkan Peninsula in the west to the Transcaucasus in the east that followed consumption of the Tethyan oceans. There is a broad mix of papers throughout the volume: wide-ranging review papers on ocean development and extensional tectonics are followed by detailed descriptions of petrology and geochemistry and geographically focused studies on basin evolution, specific aspects of extensional and strike-slip tectonics and discussions of the relationship of magmatic activity to the tectonic development of the area.
Tectonics and Magmatism in Turkey and the Surrounding Area presents up-to-date results and ideas from a large number of international contributors on a wide range of current research activity in this region. It is essential reading for all geoscientists with an interest in both academic and applied aspects of eastern Mediterranean geology.