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Important Papers

1-     Şengör, A.,M.,C., (2020). Orogenic Belts. In: Gupta H.K. (Ed.). Encyclopedia of Solid Earth Geophysics, chapter 253-1, further reading reference list.

2-     Şengör, A.,M.,C., Yazıcı, M. (2020). The aetiology of the neotectonic evolution of Turkey. Mediterranean Geoscience Reviews: 1-13. 
https://doi.org/10.1007/s42990-020-00039-0
     The neotectonics of Turkey comprises a time slice since about the end of the Oligocene and has been dominated by the shortening of Eastern Turkey, which created the Turkish–Iranian high plateau, extension in western Turkey, which created the Aegean Sea and the basin-and-range system of western Anatolia and the escape westward from the converging jaws of Arabia and Eurasia along the North and East Anatolian transform faults onto the Hellenic/Cypriot subduction zone. The escape of Turkey along the North and East Anatolian Faults began when eastern Turkey was still at subsea level, while western Turkey was a high plateau of some 3 km elevation. These inferences make it unlikely that the gravitational potential of the Turkish–Iranian Plateau initiated the escape. The pull of the Hellenic/Cypriot subduction system seems infuential in western Turkey, but not necessarily in creating the escape regime. The high topography in eastern Turkey developed gradually between the Serravallian and the present coevally as western Turkey lost elevation, which probably aided in accelerating the rate of the escape.

3-    Şengör, A.M.C., Lom, N., Sunal, G. Zabcı, C., Sancar, T., (2019). The phanerozoic palaeotectonics of Turkey. Part I: an inventory. Med. Geosc. Rev. 1, 91–161 . 
https://doi.org/10.1007/s42990-019-00007-3.
    This paper presents an inventory of the relevant information to delineate the Tethyside sutures and the continental blocks they stitch in Turkey and to summarise their history. A palinspastic palaeogeographic/palaeotectonic interpretation is reserved for the second part of this paper and in a third paper we hope to deal with its neotectonic episode. In Turkey there are two groups of Tethyside sutures: Cimmeride sutures corresponding to the closure of the Palaeo-Tethys and its dependencies such as back-arc basins and Alpide sutures corresponding to the welding lines of the Neo-Tethyan oceans. During the Palaeozoic, the entire area of Turkey was a part of the northern margin of Gondwana-Land, along which subduction seems to have been continuous at least since the Devonian, possibly since the Ordovician. During the early Carboniferous a Lycaonian back-arc basin disrupted this margin from the western end of the country to the eastern part of the Taurus Mountains. In the latest Permian another extensional basin began opening the Karakaya Basin, which seems to have been coeval and in places confluent with the western segment of the northern branch of the Neo-Tethys in Turkey. This rifting largely dislodged the future pieces of the Sakarya Continent and the Rhodope–Pontide Fragment from Gondwana-Land. Another region of Permian extension rimmed the present-day eastern Mediterranean and extended via the Bitlis Suture in southeastern Turkey into the Zagros collision zone in Iran. Finally, the body today constituting the Sakarya Continent rifted off the southern margin of the Rhodope–Pontide Fragment opening what has been called the Intra-Pontide Ocean. These various rifting events created only two independent continental pieces: the Sakarya Continent and the Kırşehir Block, the latter originally attached to the eastern end of the Bitlis Massif. Subduction commenced during the Aptian all along the southern margin of the Sakarya Continent and Laurasia where the Rhodope–Pontide Fragment formed a Sumatra-type continental margin arc. Successive rifting events north of this arc eventually opened the Black Sea, isolating the Rhodope–Pontide Fragment from Laurasia. In the main body of the text we provide the data on which such interpretations are based and evaluate some alternative suggestions.

4-  
  Şengör, A. C., & Yilmaz, Y. (1981). Tethyan evolution of Turkey: a plate tectonic approach. Tectonophysics, 75(3-4), 181-241. 
https://doi.org/10.1016/0040-1951(81)90275-4.
    The Tethyan evolution of Turkey may be divided into two main phases, namely a Palaeo-Tethyan and a Neo-Tethyan, although they partly overlap in time. The Palaeo-Tethyan evolution was governed by the main south-dipping (present geographic orientation) subduction zone of Palaeo-Tethys beneath northern Turkey during the Permo-Liassic interval. During the Permian the entire present area of Turkey constituted a part of the northern margin of Gondwana-Land. A marginal basin opened above the subduction zone and disrupted this margin during the early Triassic. In this paper it is called the Karakaya marginal sea, which was already closed by earliest Jurassic time because early Jurassic sediments unconformably overlie its deformed lithologies. The present eastern Mediterranean and its easterly continuation into the Bitlis and Zagros oceans began opening mainly during the Carnian—Norian interval. This opening marked the birth of Neo-Tethys behind the Cimmerian continent which, at that time, started to separate from northern Gondwana-Land. During the early Jurassic the Cimmerian continent internally disintegrated behind the Palaeo-Tethyan arc constituting its northern margin and gave birth to the northern branch of Neo-Tethys. The northern branch of Neo-Tethys included the Intra-Pontide, Izmir—Ankara, and the Inner Tauride oceans. With the closure of Palaeo-Tethys during the medial Jurassic only two oceanic areas were left in Turkey: the multi-armed northern and the relatively simpler southern branches of Neo-Tethys. The northern branch separated the Anatolide—Tauride platform with its long appendage, the Bitlis—Pötürge fragment from Eurasia, whereas the southern one separated them from the main body of Gondwana-Land. The Intra-Pontide and the Izmir—Ankara oceans isolated a small Sakarya continent within the northern branch, which may represent an easterly continuation of the Paikon Ridge of the Vardar Zone in Macedonia. The Anatolide-Tauride platform itself constituted the easterly continuation of the Apulian platform that had remained attached to Africa through Sicily. The Neo-Tethyan oceans reached their maximum size during the early Cretaceous in Turkey and their contraction began during the early late Cretaceous. Both oceans were eliminated mainly by north-dipping subduction, beneath the Eurasian, Sakaryan, and the Anatolide- Tauride margins. Subduction beneath the Eurasian margin formed a marginal basin, the present Black Sea and its westerly prolongation into the Srednogorie province of the Balkanides, during the medial to late Cretaceous. This resulted in the isolation of a Rhodope—Pontide fragment (essentially an island arc) south of the southern margin of Eurasia. Late Cretaceous is also a time of widespread ophiolite obduction in Turkey, when the Bozkir ophiolite nappe was obducted onto the northern margin of the Anatolide—Tauride platform. Two other ophiolite nappes were emplaced onto the Bitlis—Pötürge fragment and onto the northern margin of the Arabian platform respectively. This last event occurred as a result of the collision of the Bitlis—Pötürge fragment with Arabia. Shortly after this collision during the Campanian—Maastrichtian, a subduction zone began consuming the floor of the Inner Tauride ocean just to the north of the Bitlis—Pötürge fragment producing the arc lithologies of the Yüksekova complex. During the Maastrichtian—Middle Eocene interval a marginal basin complex, the Maden and the Çüngüş basins began opening above this subduction zone, disrupting the ophiolite-laden Bitlis—Pötürge fragment. The Anatolide-Tauride platform collided with the Pontide arc system (Rhodope—Pontide fragment plus the Sakarya continent that collided with the former during the latest Cretaceous along the Intra Pontide suture) during the early to late Eocene interval. This collision resulted in the large-scale south-vergent internal imbrication of the platform that produced the far travelled nappe systems of the Taurides, and buried beneath these, the metamorphic axis of Anatolia, the Anatolides. The Maden basin closed during the early late Eocene by north-dipping subduction, synthetic to the Inner-Tauride subduction zone that had switched from south-dipping subduction beneath the Bitlis—Pötürge fragment to north dipping subduction beneath the Anatolide—Tauride platform during the later Palaeocene. Finally, the terminal collision of Arabia with Eurasia in eastern Turkey eliminated the Çüngüş basin as well and created the present tectonic regime of Turkey by pushing a considerable piece of it eastwards along the two newly-generated transform faults, namely those of North and East Anatolia. Much of the present eastern Anatolia is underlain by an extensive mélange prism that accumulated during the late Cretaceous—late Eocene interval north and east of the Bitlis—Pötürge fragment.

 5-    Okay, A. I., & Tüysüz, O. (1999). Tethyan sutures of northern Turkey. Geological Society, London, Special Publications156(1), 475-515. 
Link.
     The two main Tethyan sutures of Turkey, the İzmir-Ankara-Erzincan and the Intra-Pontide sutures, are reviewed through several well-studied transects crossing the suture regions. Both sutures have formed during the Early Tertiary continental collisions following northward subduction of Tethyan oceanic lithosphere. The İzmir-Ankara-Erzincan suture is represented along most of its c. 2000 km length by Paleocene and younger thrust, which emplace the upper crustal rocks of the northern continent over that of the southern continent with an intervening tectonic layer of Cretaceous subduction-accretion complexes. These thrusts constitutes a profound stratigraphic, structural, magmatic and metamorphic break, of at least Carboniferous to Palaeocene age and form the main boundary between Laurasia and Gondwana in the Turkish transect. Voluminous subduction-accretion complexes of Triassic and Cretaceous ages (Neo-Tethys) respectively have been consumed along the suture. The final continental collision along the Izmir-Ankara-Erzincan suture was slightly diachronous and occurred in the earliest Palaeocene to the west and in the Late Palaeocene to the east. The c. 800 km long IntraPontide suture is younger in age and have formed during the Early Eocene and younger continental collisions linked to the opening of the Western Black Sea Basin as an oceanic back-arc basin. At present the North Anatolian Fault, which came into existence in the Late Miocene, follows the course of the older Intra-Pontide suture. 
 
6- Okay, A. I., & Nikishin, A. M. (2015). Tectonic evolution of the southern margin of Laurasia in the Black Sea region. International Geology Review57(5-8), 1051-1076. 
https://doi.org/10.1080/00206814.2015.1010609.
     The Black Sea region comprises Gondwana-derived continental blocks and oceanic subduction complexes accreted to Laurasia. The core of Laurasia is made up of an Archaean–Palaeoproterozoic shield, whereas the Gondwana-derived blocks are characterized by a Neoproterozoic basement. In the early Palaeozoic, a Pontide terrane collided and amalgamated to the core of Laurasia, as part of the Avalonia–Laurasia collision. From the Silurian to Carboniferous, the southern margin of Laurasia was a passive margin. In the late Carboniferous, a magmatic arc, represented by part of the Pontides and the Caucasus, collided with this passive margin with the Carboniferous eclogites marking the zone of collision. This Variscan orogeny was followed by uplift and erosion during the Permian and subsequently by Early Triassic rifting. Northward subduction under Laurussia during the Late Triassic resulted in the accretion of an oceanic plateau, whose remnants are preserved in the Pontides and include Upper Triassic eclogites. The Cimmeride orogeny ended in the Early Jurassic, and in the Middle Jurassic the subduction jumped south of the accreted complexes, and a magmatic arc was established along the southern margin of Laurasia. There is little evidence for subduction during the latest Jurassic–Early Cretaceous in the eastern part of the Black Sea region, which was an area of carbonate sedimentation. In contrast, in the Balkans there was continental collision during this period. Subduction erosion in the Early Cretaceous removed a large crustal slice south of the Jurassic magmatic arc. Subduction in the second half of the Early Cretaceous is evidenced by eclogites and blueschists in the Central Pontides and by a now buried magmatic arc. A continuous extensional arc was established only in the Late Cretaceous, coeval with the opening of the Black Sea as a back-arc basin.

7-   Le Pichon, X., Şengör, A. C., Kende, J., İmren, C., Henry, P., Grall, C., & Karabulut, H. (2016). Propagation of a strike-slip plate boundary within an extensional environment: the westward propagation of the North Anatolian Fault. Canadian Journal of Earth Sciences, 53(11), 1416-1439. 
https://doi.org/10.1139/cjes-2015-0129
    We document the establishment of the Aegea–Anatolia/Eurasia plate boundary in Pliocene–Pleistocene time. Before 2 Ma, no localized plate boundary existed north of the Aegean portion of the Anatolia plate and the shear produced by the motion of Anatolia–Aegea with respect to Eurasia was distributed over the whole width of the Aegean – West Anatolian western portion. In 4.5 Ma, a shear zone comparable to the Gulf of Corinth was formed in the present Sea of Marmara. The initial extensional basins were cut by the strike-slip Main Marmara Fault system after 2.5 Ma. Shortly after, the plate boundary migrated west of the Sea of Marmara along the northern border of Aegea from the North Aegean Trough, to the Gulf of Corinth area and to the Kefalonia Fault. There, it finally linked with the northern tip of the Aegean subduction zone, completing the system of plate boundaries delimiting the Anatolia–Aegea plate. We have related the change in the distribution of shear from Miocene to Pliocene to the formation of a relatively undeforming Aegea block in Pliocene that forced the shear to be distributed over a narrow plate boundary to the north of it. We attribute the formation of this block to the northeastward progression of the oceanic Ionian slab. We propose that the slab cuts the overlying lithosphere from asthenospheric sources and induces a shortening environment over it.