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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The United States, Britain and Turkey's search for security, 1945-1952

Athanassopoulou, Ekavi January 1995 (has links)
In 1952 Turkey was invited to become a member of the North Atlantic Treaty Organisation. This study examines the context of the Turkish demand for an American security guarantee and of American and British security interests in the Eastern Mediterranean in the late 1940s in the light of Cold War developments. The postwar weakness of Great Britain, who had until then guarantied the status quo in the area induced Ankara to tum to the United States as a guarantor of Turkish political independence and territorial integrity against a powerful Soviet Union. The Turks asked for a formal alliance with the Americans, but this proved to be a difficult task. In the eyes of American military and State Department officials Turkey was a barrier against Soviet penetration in the Middle East. Hence, it was thought necessary to strengthen her resistance to the Soviets through the provision of American military aid. However,, Washington was reluctant to stretch the United States' resources by extending its commitments to this area which was still thought to be a British military responsibility. Britain for her part responded to Turkish demands in accordance with her general interests in the Middle East. London regarded Turkey as a part of Middle East defence: hence, it favoured an American commitment to Turkey, but mainly as a means of getting the Americans involved in the area as a whole. The evolution of American military thinking regarding Europe and the Middle East in 1951, made Washington to revise its policies towards Ankara. The realisation of Turkey's importance for the organisation of defence both in Western Europe and the Middle East along with the fear that Turkey might turn neutral in the event of a conflict with the Soviet Union induced the Americans to meet Turkish demands in what appeared to be the easiest way, that is, inviting Turkey to join the Atlantic Alliance. The study concludes that in the late 1940s Ankara followed a pragmatic foreign policy. Turkish leaders had a clear perception of their country's interests and were particularly alert at exploiting the circumstances which would promote them. In contrast, the foreign policy of the United States towards the Eastern Mediterranean was still developing and lacked the determination of a great power. Britain, on the other hand, continued to plan like a great power although it was obvious that she was not in a position to do so any more.
2

Field-based evidence of sedimentary and tectonic processes related to continental collision : the Early Cenozoic basins of Central Eastern Turkey

Booth, Matthew Graham January 2013 (has links)
Turkey is widely accepted to have formed from a collage of microcontinents that rifted from the northern margin of Gondwana and assembled from the Mesozoic to Mid Cenozoic in response to the closure, collision and suturing of numerous oceanic strands in the Eastern Mediterranean. Sedimentary-tectonic basins, which formed during ocean basin closure, can yield important information about the evolution, timing and processes related to the closure of these oceanic strands. The Darende Basin and the adjacent Hekimhan Basin are two sedimentary-tectonic basins which developed during the collision and suturing of the Neotethys Ocean in the Eastern Mediterranean. The Darende and Hekimhan Basins developed as part of the northern margin of the Tauride microcontinent during the collision and suturing of Neotethys. Both basins exhibit a Jurassic to Cretaceous regional carbonate platform 'basement' overlain by a dismembered ophiolite, which was emplaced southwards during the Late Cretaceous. The basins then developed in two main phases: In the Darende Basin the first phase is characterised by non-marine clastic sediments, overlain by transgressive shallow-marine rocks. In the Hekimhan Basin, hemi-pelagic facies are deposited synchronously with the eruption of within plate-type alkaline basaltic-trachytic lavas and associated volcaniclastic sediments (later intruded by a syenitic pluton) under an extensional tectonic regime. A Paleocene-aged unconformity followed. A second phase of basin evolution during the Eocene is characterised in both basins by the deposition of variable sedimentary facies including conglomerate, sandstone, marl, shallow-marine nummulitic limestone and evaporites (and localised basaltic eruptions). These record successive deepening, shallowing and finally emergence of both basins during the Late Eocene. The Oligocene is represented by continental fluvial deposits that are only exposed in the Hekimhan Basin. The deposition of faunally diverse, shallow-marine, Miocene limestones, Pliocene subaerial basalts and Pliocene-Recent continental deposits in both basins completes the sequence. The following tectonically and eustatically controlled stages of basin development are inferred: 1) Late Cretaceous extension initiated basin development (after ophiolite emplacement), possibly related to immediate isostatic compensation and on-going slabpull during northward subduction of the remaining Neotethyan oceanic crust. The eruption of within-plate lavas and the intrusion of alkaline syenite bodies in the Hekimhan Basin reflect this extensional setting; 2) Emergence of the Darende and Hekimhan Basins in the latest Cretaceous was possibly controlled by regional flexural uplift as the down-going plate approached the subduction zone to the north (and was possibly also influenced by eustatic sea-level change); 3) Early Eocene flexural subsidence related to ‘soft collision’ of the Tauride microcontinent with Eurasia, coupled with a significant eustatic sea level rise, allowed sedimentation to resume; 4) Mid-Late Eocene ‘hard collision’ resulted in regional uplift, progressive isolation and subaerial exposure of the basins; 5) Suture tightening and compression, during the Late Eocene- Miocene, resulted in reactivation of pre-existing extensional faults and terminated marine sedimentation. Both basins were affected by predominantly sinistral strike-slip faulting during the Plio-Quaternary westward tectonic escape of Anatolia.
3

Contextualizing the emergence and the development of Turkish Nationalism in Cyprus : the British imperial impact, 1923-1939

Xypolia, Ilia January 2014 (has links)
In Cyprus that experienced British imperial rule from 1878 until 1960, Greek and Turkish nationalism developed at different historical periods and at different paces. Relations between Turkish Cypriots and the British on the one hand, and Greek Cypriots and the British on the other, were asymmetrical. During the colonial era in Cyprus, the Muslim community had undergone an enormous change in terms of national/ethnic identity and class characteristics. Turkish Cypriot nationalism developed belatedly as a militant nationalist and anti-Enosis movement. Against this background this thesis explores the relationship between the emergence of the Turkish national identity and the British colonial rule because the latter set out the international, political, social and ideological context wherein the Turkish national identity was shaped. In particular this thesis focusing on the period between the two World Wars (1923-1939) when the transformation of the Muslims of Cyprus into Turkish Cypriots occurred, examines the extent to which the British rule affected the process of development of Turkish nationalism on Cyprus. This thesis discusses educational and administrative policies implemented by the British rule that had an impact on the politics of the Muslim community of Cyprus. The development of Turkish Cypriot national identity is also placed in the broader international context of the Eastern Mediterranean, with due attention being paid to the role of both Turkey and Italy. The impact of the Kemalist reforms on Cyprus and the resultant division of Turkish Cypriots into two conflicting groups of Kemalists and traditionalists is presented, and British fears of Italian expansionism under Mussolini are also examined. The final conclusion is that while a Turkish Cypriot identity would inevitably have developed, the divisive way it developed was a result of the imperial policies the British rule implemented during the period in question.
4

Mesozoic to Early Tertiary tectonic-sedimentary evolution of the Northern Neotethys Ocean : evidence from the Beysehir-Hoyran-Hadim Nappes, S.W. Turkey

Andrew, Theo January 2003 (has links)
The Beyşehir-Hoyran-Hadim Nappes crop out over 700km, from east to west in the Pisidian and Central Taurus Mountains of southern Turkey. During this study, field obsevations of lithological, structural and sedimentological features are combined with igneous geochemical data derived from samples collected to help redefine a series of tectono-stratigraphic units and also determine the origin of the Beyşehir-Hoyran-Hadim Nappes. Above a regionally autochthonous Tauride carbonate platform, the Beyşehir-Hoyran Nappes begin with Ophiolitic Melange, consisting of blocks of neritic and pelagic limestone, basalt, serpentinite, radiolarian chert and, in places, amphibolite-grade metamorphic sole-type rocks, together set in a highly sheared siltstone and mudstone matrix. Locally, large slices of serpentinized harzburgite are incorporated in the melange. The peridotite sheets include lenses of chromitite and dunite and are cut by a series of dolerite dykes. The higher thrust sheets in the Hadim area begin with the Korualan Unit; a thrust sheet (ca. 400m thick) of mainly redeposited carbonates, quartzose sandstones and mudstones of Mid-Late Triassic age, interpreted as a proximal slope/base-of-slope succession. Regionally above is the Huğlu-type Unit; a thrust sheet (ca. 1 km thick) of Mid-Late Triassic intermediate-acidic extrusives, volcaniclastics and minor pelagic carbonates, interpreted as a continental rift. Post-rift subsidence in this thrust sheet is recorded by thin (<100m thick) Upper Triassic-Upper Cretaceous pelagic carbonate and radiolarian chert, depositionally above. The uppermost thrust sheet, the Boyali Tepe-type Unit, comprises broken formation and melange, including Jurassic shallow-water carbonate, Ammonitico Rosso condensed pelagic limestone, radiolarian chert and Upper Cretaceous pelagic limestone, representing a Bahaman-type carbonate platform which subsided in Early Jurassic time. Anastomosing zones of tectonic-sedimentary melange separate these higher units. The Beyşehir-Hoyran Nappes document Triassic rifting and Jurassic-Cretaceous passive margin subsidence bordering the Northern Neotethyan Ocean. The Late Cretaceous harzburgitic ophiolite probably formed above a northerly dipping subduction zone within the Neotethyan ocean basin. Ophiolitic melange formed along the leading edge of the overiding plate. The ophiolite was emplaced southwards onto the northern margin of the Tauride platform in latest Cretaceous time, probably during collision of the passive margin with a trench. The nappe pile and underlying platform (Hadim Nappe) were thrust ca. 150km further south in Late Eocene time during regional continental collision and suture zone tightening. Several alternative palaeo-tectonic models are considered and tested in the light of data presented from this study. Assuming ‘in-sequence’ thrusting, the Beyşehir-Hoyran Nappes restore to a location north of a northerly Neotethyan spreading axis. More probably, they originated near the south margin of the northern Neotethys, but reached their position by ‘out-of-sequence thrusting’. Formation within a localised southerly strand of the northern Neotethys (Inner Tauride ocean) is more probable than within the main Neotethys further north. Wider implications for the Tethyan ocean as a whole and several other orogenic belts are also considered.
5

Η τεκτονο-στρωματογραφική εξέλιξη της ΝΑ Μεσογείου, με έμφαση στη λεκάνη του Ηροδότου, στην κατεύθυνση ανάπτυξης πεδίων υδρογονανθράκων

Ηλία, Χρίστος 11 July 2013 (has links)
Η Μεσόγειος θάλασσα είναι μια κλειστή θάλασσα που μπορεί να χωριστεί σε δυτικό και ανατολικό τμήμα. Η ανατολική Μεσόγειος είναι μεγαλύτερη σε μέγεθος από την δυτική και παρουσιάζει έντονο γεωλογικό ενδιαφέρον σε διάφορους τομείς. Συγκεκριμένα η νοτιοανατολική Μεσόγειος με την παρουσία της Μεσογειακής ράχης, της Λεκάνης Λεβαντίνης, του αβυσσικού πεδίου του Ηροδότου, του κώνου του Νείλου και του ηπειρωτικού μπλοκ του Ερατοσθένη αποτελεί ένα μεγάλο πεδίο ερευνών. Ένας τομέας ερευνών που τα τελευταία χρόνια παρουσιάζει μια έξαρση είναι η ύπαρξη πεδίων υδρογονανθράκων στην περιοχή. Το μεγαλύτερο ενδιαφέρον εστιάζεται στη γεωλογική εξέλιξη δυο λεκανών, της Λεβαντίνης νοτιοανατολικά της Κύπρου και του Ηροδότου νοτιοδυτικά της Κύπρου. Οι δυο αυτές λεκάνες σχηματίστηκαν την ίδια γεωλογική περίοδο ως λεκάνες προχώρας λόγω της καταβύθισης της Αφρικανικής πλάκας κάτω από την Ευρασία. Φιλοξενούν το ίδιο περίπου πάχος ιζημάτων όπως και ίδιους τύπους ιζημάτων. Έχουν διαφορετική γεωμετρία με την λεκάνη του Ηροδότου να είναι βαθύτερη και διπλάσια σε έκταση από την λεκάνη της Λεβαντίνης. Για την λεκάνη της Λεβαντίνης υπάρχουν αρκετά στοιχεία για την στρωματογραφία της, και τη δυνατότητα της να αναπτύξει πεδία υδρογονανθράκων, καθώς και πιστοποιημένα αποθέματα πετρελαίου και φυσικού αερίου. Μέσω αυτών των στοιχείων και γνωρίζοντας ότι η λεκάνη Ηροδότου έχει ίδια ηλικία σχηματισμού συγκρίναμε τις δυο λεκάνες όσον αφορά την παλαιογεωγραφική τους εξέλιξη και την στρωματογραφία τους με σκοπό να εκτιμήσουμε τα αποθέματα που μπορεί να φιλοξενεί η λεκάνη του Ηροδότου. Σύγχρονα λαμβάνουμε υπόψη και το ρόλο που διαδραματίζουν στην εξέλιξη των λεκανών αλλά και της ευρύτερης περιοχής, το ηπειρωτικό μπλοκ του Ερατοσθένη και ο κώνος του Νείλου Παρουσιάζονται επίσης σεισμικά δεδομένα στα οποία φαίνονται άμεσοι δείκτες υδρογονανθράκων DHI (Direct Hydrocarbons Indicators) αλλά και άλλα στοιχεία που αφορούν την εξέλιξη των λεκανών. Αυτοί οι δείκτες συνδέονται άμεσα με σημεία στα οποία υπάρχουν διαφυγές υδρογονανθράκων, όπου πιθανά να υπάρχουν πεδία υδρογονανθράκων. Επίσης αναφέρεται ποια πρέπει να είναι τα κριτήρια ούτως ώστε να αναπτυχθούν υδρογονάνθρακες. Τέλος παρουσιάζεται ένας συγκεντρωτικός πίνακας με όλα τα συγκριτικά στοιχεία των δυο λεκανών, που μας δείχνει τα πιστοποιημένα στοιχεία της λεκάνης της Λεβαντίνης και τις εκτιμήσεις για την λεκάνη του Ηροδότου μέσα από την σύγκριση της με τη λεκάνη Λεβαντίνης. / The Mediterranean Sea is an close sea that can be divided into western and eastern part. The Eastern Mediterranean is larger in size than the west and has a big geological interest in various fields. Specifically, the southeastern Mediterranean in the presence of the Mediterranean ridge, the Levantine basin, the Herodotus abyssal plain, the Nile cone and the Eratosthenes continental block, is a large field of investigation. One of the main interesting topics is the genesis and the development of hydrocarbon fields in the area. The major focus is on the palaeogeographic evolution of two major basins, such as Levantine basin and Herodotus basin. These two basins were formed in the same geological period as foreland basins due to subduction of the African plate beneath Eurasia. Accommodate approximately the same sediment thickness and the same sediment types. They have different geometry with Herodotus basin is deeper and doubles in size from the Levantine basin. For the Levantine basin there is enough evidence for the stratigraphy, and the ability to develop oil fields and they are certified reserves of petroleum and natural gas. Through these elements and knowing that Herodotus basin formed in the same age we compared the palaeogeographic evolution and stratigraphy of the two basins with a view to assess the stocks that can accommodate the Herodotus basin. At the same time we take into account the role they played in the evolution of the basins, the Eratosthenes continental block and the Nile cone. Seismic data are also presented which show direct hydrocarbon indicators DHI (Direct Hydrocarbons Indicators) and other data concerning the evolution of the two basins. These indicators are directly linked to places where there are leaks of hydrocarbons, which are thought to be hydrocarbon fields. Finally we present a table summarizing all the comparisons of the two basins, which shows us the certified data of the Levantine basin and the estimated oil and gas reserves of Herodotus basin through the comparison of the Levantine basin.
6

La construction d’un cadre méthodologique pour l’élaboration de projets urbains durables en Syrie / The construction of a methodological framework for the development of sustainable urban projects in Syria

Hajjar, Abboud 10 June 2014 (has links)
Après l'apparition de la première génération des projets urbains dans les Pays du Sud et de l'Est de la méditerranée (PSEM), le développement et la formulation des stratégies, outils et normes sont perçus, par les experts et les spécialistes, comme une nécessité absolue pour évoluer la mise en œuvre du développement durable dans les projets urbains, ainsi que l'évolution de sa contribution dans l'action urbaine globale, afin de passer à la « ville durable ». Dans cette perspective, notre thèse se focalise sur le développement de démarches opérationnelles qui permettent de porter une nouvelle réflexion sur la fabrication urbaine en Syrie, et surtout de la ville d'Alep, qui est le terrain d'expérimentation et d'application de cette thèse. Dans ce pays, l'enjeu du développement urbain durable s'est imposé, avant la guerre actuelle, dans les politiques publiques urbaines. Entre les années 2000 et 2011, les autorités nationales syriennes (l'Etat central) et ses instances locales (les autorités publiques locales) ont lancé plusieurs programmes et projets urbains, souvent en collaboration avec des bailleurs du fonds internationaux (Banque Mondiale, GIZ, Union Européenne...).Un des objectifs de cette thèse est de proposer un cadre métrologique à partir des approches françaises de la mise en œuvre des projets de quartiers durables et/ou éco-quartiers, non pas en procédant à un transfert d'expériences totalement inopportunes, mais en effectuant une analyse de la situation de la ville d'Alep, pour la mise en place des outils permettant d'orienter les acteurs locaux de l'aménagement urbain (collectivité locales, bureau d'études, ….) pour la phase post-guerre, et d'accompagner la conception des projets urbains durables à l'interface des problèmes et des enjeux locaux / After the appearance of the first generation of sustainable urban projects in Southern and Eastern Mediterranean Countries (SEMC), the development of strategies, tools and standards are perceived by experts and specialists, as an absolute necessity to move the implementation of sustainable development in urban projects and the evolution of its contribution in the overall urban action to move to the "sustainable city». In this perspective, our thesis focuses on the development of operational procedures that can bring new thinking on urban practices in Syria, and especially the city of Aleppo, which is the experimental site of this thesis. In this country, the issue of sustainable urban development was imposed before the current war in urban public policy. Between 2000 and 2011, the Syrian national authorities (central government) and local authorities have launched several programs and urban projects, often in collaboration with the international donor funds (World Bank, GIZ, European Union ...).One objective of this thesis is to propose a methodological framework from the French approaches to the implementation of sustainable neighborhood projects, not by taking a totally inappropriate transfer of experience, but performing an analysis of the situation of the city of Aleppo, for the implementation tools to guide local actors of urban development ( local community office, .... ) for the post-war, and to support the design of sustainable urban projects at the interface of local problems and issues
7

Redefining an alliance : Greek-US relations, 1974-1980

Antonopoulos, Athanasios January 2017 (has links)
In 1974 following the Cyprus Crisis, the bilateral alliance between Greece and the United States entered a new period. The bilateral relations, traditionally close since the emergence of the Cold War, faced a set of challenges. Turkey’s invasion of Cyprus and the collapse of the Greek dictatorship, which enjoyed close ties with Washington, gave rise to anti-Americanism in Greek society. Moreover, Washington’s inability to contain Turkish aggression frustrated the Greek government. In response to the invasion of Cyprus, Athens announced Greece’s withdrawal from NATO with the hope of securing the active involvement of the US and NATO in the Greek-Turkish dispute. These developments required readjustments to Greek-US policies and strategies to overcome obstacles and secure their objectives. Greece’s withdrawal from and return to NATO after six years, in October 1980, symbolises best this distinct period of Greek-US cooperation. The traditional historical narrative states that after 1974 the priorities of successive Greek governments were increasingly directed at managing the country’s accession to European Economic Community while developing closer cooperation with the Balkan states. The United States remained another significant ally of Greece. This thesis emphasises that the Greek governments between 1974 and 1980 regarded the United States as the single most important ally for the Greek national security policy. The Greek governments realised that only Washington could assist Greece with both Soviet and Turkish threats. Washington, meanwhile, prioritised retaining close ties with both Greece and Turkey and an eventual re-build of NATO’s Southern Flank. What is significant is that President Carter put aside his idealistic declarations made on the campaign trail and adopted fully Ford/Kissinger’s approach toward Greece, Turkey, and Cyprus, i.e. the Eastern Mediterranean. Hence, the thesis underlines the element of continuity between the US administrations in the second half of 1970s. The thesis makes a significant contribution to Cold War scholarship regarding bilateral relations within the West during the era of détente. Scholars has largely overlooked the US’s relationships with Greece, Turkey, and Cyprus even though the Eastern Mediterranean region dominated the foreign policy agendas of both Ford and Carter administrations. This study argues that President Ford’s handling of relations with Greece was focused on crisis management rather than crisis solving. More significantly, although unrecognised at the time, President Carter’s relations with Greece were a significant success. Ford and Carter responded to the Eastern Mediterranean questions in ways that reflect significant continuities in their approaches. Ford and his Secretary of State Henry Kissinger developed the concept of a ‘balanced approach’ towards Athens and Ankara in political, economic, and military terms that aimed at ensuring close ties with both. Carter followed the same policy concept. Carter succeeded in seeing Greece’s return to full NATO membership while resisting being dragged into the centre of Greek-NATO negotiations. During these years the Greek government also scored significant successes. Greek pressure ensured that Washington devoted equal attention to Greece and Turkey, a much more powerful regional power. Similarly, Greece received significant US economic aid while Turkey faced a strict US arms embargo. By 1980, however, the implications of the Iranian Revolution and the end of détente mandated that Turkey had to take precedence over Greece in the US’s policy considerations.
8

Provenance-related studies of Triassic-Miocene Tethyan sedimentary and igneous rocks from Cyprus

Chen, Guohui January 2018 (has links)
Cyprus comprises three tectono-stratigraphic terranes: first, the Troodos Massif made up of Late Cretaceous oceanic lithosphere and its sedimentary cover in the centre of the island; secondly, the Mamonia Complex (and Moni Melange) a passive margin lithological assemblage in the west (and south) and thirdly, the Kyrenia Range, an active margin lithological assemblage in the north. This study focuses on the sedimentary cover of the Troodos Ophiolite in W Cyprus, the Triassic-Cretaceous sedimentary rocks of the Mamonia Complex and Late Cretaceous-Miocene igneous and sedimentary rocks in the Kyrenia Range, mainly based on combined sedimentology, geochemistry and geochronological dating. The Late Triassic-Early Cretaceous Mamonia Complex, SW Cyprus (and the Moni Melange, S Cyprus) represent parts of the emplaced passive continental margin of the S Neotethys. Late Triassic sandstones are characterised by a predominantly felsic source, with a subordinate mafic contribution. Jurassic-Early Cretaceous sandstones have a polycyclic felsic origin. Geochemical analyses are suggestive of progressive weathering and sediment recycling/sorting. The dominance of Ediacaran-Cryogenian and Tonian-Stenian-aged detrital zircon populations is suggestive of an ultimate north Gondwana source, probably recycled from Palaeozoic siliciclastic sedimentary rocks within Anatolia to the north. Similar detrital zircon populations characterise Early Cretaceous deltaic sandstone of the Moni Melange, S Cyprus. Sporadic Late Cretaceous subduction-related magmatism, represented by a Campanian volcaniclastic sequence (80.44±1.0 Ma) inWCyprus and a Late Campanian felsic volcanogenic sequence (72.9±1.0 Ma) in N Cyprus, represents early and more advanced stages of northward subduction during closure of the S Neotethys. Specifically, the Kannaviou Formation in W Cyprus (up to 750 m thick) is made up of deep-marine volcaniclastic sandstones that were mostly deposited by gravity flows and as air-fall tuff, interbedded with clay and radiolarian mudstones. Petrographic and geochemical analyses are indicative of a volcanic arc source, with deposition in a fore-arc basin. Petrographic evidence of terrigenous input (e.g. muscovite, muscovite schist, polycrystalline quartz) points to a subordinate continental source. Mineral chemistry is consistent with a volcanic arc origin. Elevated trace-element ratios in undevitrified volcanic glass (e.g. Th/Nb, Th/La) are indicative of involvement of continental crust or subducted terrigenous sediments in source-arc melting. Felsic volcanogenic rocks (Fourkovouno (Selvilitepe) Formation) in the Kyrenia Range, N Cyprus, occur as an up to 400 m-thick sequence of felsic tuffs, felsic debris-flowdeposits and rhyolitic lava flows. Geochemical analyses are indicative of evolved high-K and shoshonitic compositions, similar to those of the Andean active continental margin. Subduction continued to affect the northern continental margin of the S Neotethys in the Kyrenia Range during the Maastrichtian. This lead to the accumulation of Late Cretaceous sandstone turbidites and related basaltic volcanics, possibly in a back-arc setting. The volcanism took place in two phases (Late Cretaceous and Palaeogene-Early Eocene) during pelagic carbonate accumulation. These lavas have within-plate affinities, but with a variable subduction influence in some areas (e.g. western Kyrenia Range), which may be contemporaneous or inherited from previous subduction. The sedimentary sequences in the Kyrenia Range, N Cyprus, document diachronous closure of the S Neotethys. Late Cretaceous and Eocene sandstone turbidites, and the lower part of the overlying Oligocene-Miocene succession exhibit enrichment in ultramafic components that was probably sourced from ophiolite-related rocks in the Taurides to the north. In contrast, Miocene sandstone turbidites higher in the sequence show an increasing input of continent-derived siliciclastic material (and sorting effects). The terrigenous-influenced sediments are likely to represent erosion of thrust sheets that were emplaced from the S Neotethys onto the Arabian foreland in SE Turkey related to continental collision. Ediacaran-Cryogenian and Tonian-Stenian-aged zircons dominate the Late Cretaceous and Eocene sandstone turbidites, consistent with derivation from the Tauride micro-continent to the north and/or NE. Overlying Miocene sandstones include minor populations of Neoproterozoic-aged zircons, suggestive of reworking from source rocks of ultimately Gondwanan origin (e.g. NE Africa/Arabian-Nubian Shield). In summary, the thesis results exemplify the interaction of tectonic processes associated with the evolution of the S Neotethys Ocean. This began in the area studied with passive margin development (Triassic-Cretaceous), and was followed by multi-stage subduction-related volcanism and sedimentation (Late Cretaceous-Miocene). Final closure of the S Neotethys in this area took place during the Late Miocene-Recent.
9

Study On Posidonia Oceanica (l.) Delile, 1813 Seagrass Meadows In The Levant Sea

Celebi, Billur 01 May 2007 (has links) (PDF)
In this thesis, the distribution and state of Posidonia oceanica meadows along the Turkish coast of the north eastern Mediterranean was investigated. The study area was a unique site due to the presence of eastern geographical limit of Posidonia oceanica meadows in Mediterranean Sea. It was aimed to assess the possible reasons of the absence and/or regression in relation to environmental changes. The study was conducted from September 2004 to January 2007 in 5 main regions between Anamur/Mersin and Samandag/Hatay. The regions were determined according to the presence/absence of Posidonia oceanica meadows / 1 region including the boundary meadow at the geographical distribution limit, 1 region western and 3 regions eastern to that boundary meadow. To describe the hydrological characteristics of the study area temperature, salinity and light were measured as abiotic descriptors. Additionally sedimentological analysis was carried out to check the suitability of the substrate type for Posidonia oceanica colonization. The main differences between the regions were found in temperature and light conditions. Both, the recordings of temperature loggers at 10 and 15 meter depths and the sea surface temperature retrieved from satellite (NOAA-AVHRR) showed that the eastern stations with no Posidonia oceanica meadows were warmer than the western stations. Consequently in this study the maximum tolerable temperature limit for Posidonia oceanica growth was determined as 28.4&deg / C from the data collected by the temperature loggers placed to natural meadows near to the boundary meadow. Generally, the whole study area had a limiting light condition for seagrass growth due to low penetration depths of the 10% of surface irradiation. This was a generalized minimum light requirement for growth of seagrasses. Especially in Mersin and Iskenderun bays the minimum required light level did not reached deeper than 10 meter depths in coastal stations. The biological parameters of the Posidonia oceanica meadows were investigated under 3 complementary methods in the first two regions. The structural descriptors were measured in-situ. The lowest shoot density and leaf lengths were found to be in boundary meadow. This meadow had also the lowest depth limit among other stations. The functional descriptors were examined by the lepidochronological and phenological analysis in laboratory. Most of the measurements varied either with respect to depth or among stations according to the abiotic factors of the stations. The lepidochronological cycles obtained from sheath thicknesses were further correlated with abiotic descriptors via a mathematical model. Finally, the first transplantation experiment of Posidonia oceanica along Turkish coasts has been conducted in 2 regions where presently no meadows exist. The survival of cuttings in one station indicated the success of the methodology, while the failure in other stations provided information on the possible reasons of absence/degradation of natural meadows in the area. These included the destructive impact of bottom trawling, the high pressure of grazing (the potential causes of Lessepsian migration) and the long term changes in climate resulting in alterations of environmental conditions such as increasing temperature and reduced light penetration.
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A Coupled Modelling Attempt Of Hydrodynamics And Ecosystem Of Northern Levantine Basin

Aydogdu, Ali 01 July 2012 (has links) (PDF)
A three-dimensional ocean model, ROMS, has been utilized to simulate the hydrodynamics and the ecosystem dynamics of the Northern Levantine Basin circulation. The model is one-way nested inside a coarser resolution Mediterranean Sea eco-hydrodynamics model, forced with realistically updated surface and lateral fluxes of momentum, mass, heat and nutrients. Scenario runs representing present and future time-slices of 5 years each have been used to investigate sensitivity to climate in the near future. Other sensitivity tests depending on model parameters and options have been performed. It is revealed that the Asia Minor Current, dominating the basin circulation, divides the basin into the two basic regions of coastal and open sea characteristics. Although satisfactory results are reached for the general behaviour of the ecosystem, the model tends to overestimate the surface chlorophyll concentration. Sea surface patterns of variables predicted by the model are compared with satellite data indicate general agreement in the seasonal patterns. Based on the selected climate change scenario for 30-40 year difference of the time slices, rises of 0.33

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