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Full-Text Articles in Earth Sciences

Ion Probe U-Pb Dating Of The Central Sakarya Basement: A Peri-Gondwana Terrane Intruded By Late Lower Carboniferous Subduction/Collision-Related Granitic Rocks, Petek Ayda Ustaömer, Ti̇mur Ustaömer, Alastair Robertson Jan 2012

Ion Probe U-Pb Dating Of The Central Sakarya Basement: A Peri-Gondwana Terrane Intruded By Late Lower Carboniferous Subduction/Collision-Related Granitic Rocks, Petek Ayda Ustaömer, Ti̇mur Ustaömer, Alastair Robertson

Turkish Journal of Earth Sciences

Ion probe dating is used to determine the relative ages of amphibolite-facies meta-clastic sedimentary rocks and crosscutting granitoid rocks within an important 'basement' outcrop in northwestern Turkey. U-Pb ages of 89 detrital zircon grains separated from sillimanite-garnet micaschist from the Central Sakarya basement terrane range from 551 Ma (Ediacaran) to 2738 Ma (Neoarchean). Eighty five percent of the ages are 90-110% concordant. Zircon populations cluster at ~550-750 Ma (28 grains), ~950-1050 Ma (27 grains) and ~2000 Ma (5 grains), with smaller groupings at ~800 Ma and ~1850 Ma. The first, prominent, population (late Neoproterozoic) reflects derivation from a source area …


Petrogenesis Of Late Cretaceous Adakitic Magmatism In The İstanbul Zone (Çavuşbaşı Granodiorite, Nw Turkey), Sabah Yilmaz Şahi̇n, Namik Aysal, Yildirim Güngör Jan 2012

Petrogenesis Of Late Cretaceous Adakitic Magmatism In The İstanbul Zone (Çavuşbaşı Granodiorite, Nw Turkey), Sabah Yilmaz Şahi̇n, Namik Aysal, Yildirim Güngör

Turkish Journal of Earth Sciences

The Çavuşbaşı granodiorite intrudes Ordovician sedimentary rocks in the western part of the İstanbul Zone (NW Turkey). The intrusion is made up mainly of granodiorite, and subordinate tonalite and quartz diorite, and has a granular texture and some special mixing textures such as antirapakivi, blade-shaped biotite, acicular apatite, spongy cellular dissolution/melting plagioclase textures. The main mafic minerals are hornblende and biotite. U-Pb in-situ dating of zircons from two samples via SHRIMP yielded weighted age values of ~68 Ma, suggesting emplacement during the Late Cretaceous. Geochemically the Çavuşbaşı granodiorite resembles adakites with high Sr/Y and La/Yb ratios, low Y and HREE …


Early Oligocene Continental Climate Of The Palaeogene Basin (Hungary And Slovenia) And The Surrounding Area, Boglarka Erdei, Torsten Utescher, Lilla Hably, Julia Tamás, Anita Roth-Nebelsick, Michaela Grein Jan 2012

Early Oligocene Continental Climate Of The Palaeogene Basin (Hungary And Slovenia) And The Surrounding Area, Boglarka Erdei, Torsten Utescher, Lilla Hably, Julia Tamás, Anita Roth-Nebelsick, Michaela Grein

Turkish Journal of Earth Sciences

This paper concentrates on the Early Oligocene palaeoclimate of the southern part of Eastern and Central Europe and gives a detailed climatological analysis, combined with leaf-morphological studies and modelling of the palaeoatmospheric CO_2 level using stomatal and \delta^1^3C data. Climate data are calculated using the Coexistence Approach for Kiscellian floras of the Palaeogene Basin (Hungary and Slovenia) and coeval assemblages from Central and Southeastern Europe. Potential microclimatic or habitat variations are considered using morphometric analysis of fossil leaves from Hungarian, Slovenian and Italian floras. Reconstruction of CO_2 is performed by applying a recently introduced mechanistic model. Results of climate analysis …


Palaeoclimate Estimates For Selected Leaf Floras From The Late Pliocene (Reuverian) Of Central Europe Based On Different Palaeobotanical Techniques, Christine Thiel, Stefan Klotz, Dieter Uhl Jan 2012

Palaeoclimate Estimates For Selected Leaf Floras From The Late Pliocene (Reuverian) Of Central Europe Based On Different Palaeobotanical Techniques, Christine Thiel, Stefan Klotz, Dieter Uhl

Turkish Journal of Earth Sciences

To provide quantitative palaeoclimate estimates based on different palaeobotanical techniques for three contemporaneous Pliocene leaf floras, we applied the Coexistence Approach (CoA), leaf margin analysis (LMA), the Climate Leaf Analysis Multivariate Program (CLAMP) and the European Leaf Physiognomic Approach (ELPA). Furthermore, we compared recently published estimates from an additional locality with our data. The leaf physiognomic techniques yield lower mean annual temperatures than the CoA, which is most likely caused by taphonomic biases. Due to these potential biases we are in favour of the CoA as the most reliable method, and its palaeotemperature estimates show similar temperatures for all localities. …


Palaeoclimate Evolution In Siberia And The Russian Far East From The Oligocene To Pliocene – Evidence From Fruit And Seed Floras, Svetlana Popova, Torsten Utescher, Dmitry Gromyko, Angela Bruch, Volker Mosbrugger Jan 2012

Palaeoclimate Evolution In Siberia And The Russian Far East From The Oligocene To Pliocene – Evidence From Fruit And Seed Floras, Svetlana Popova, Torsten Utescher, Dmitry Gromyko, Angela Bruch, Volker Mosbrugger

Turkish Journal of Earth Sciences

The Cenozoic continental deposits of Western Siberia, Eastern Siberia and the Russian Far East are best described on the basis of carpological records. The palaeoclimate evolution has been reconstructed quantitatively (Coexistence Approach) providing inferred data on temperature, precipitation and the mean annual range of these parameters. Climate curves document the transition from very warm and humid conditions in the Late Oligocene via the Middle Miocene Climatic Optimum to a cool temperate climate during the Pliocene. Compared with other time intervals the Miocene climate is the most comprehensively reconstructed. For the Middle Miocene the Siberian and Far Eastern data are combined …


Palaeoclimatic Estimates For The Late Pliocene Based On Leaf Physiognomy From Western Yunnan, China, Sanping Xie, Sun Bainian, Jinyu Wu, Zhicheng Lin, Defei Yan, Liang Xiao Jan 2012

Palaeoclimatic Estimates For The Late Pliocene Based On Leaf Physiognomy From Western Yunnan, China, Sanping Xie, Sun Bainian, Jinyu Wu, Zhicheng Lin, Defei Yan, Liang Xiao

Turkish Journal of Earth Sciences

Based on leaf physiognomy of the Late Pliocene Tuantian megaflora from the Mangbang Formation of Tengchong County in western Yunnan, a quantitative reconstruction of palaeoclimate was performed with Leaf Margin Analysis (LMA) methodology and the Climate-Leaf Analysis Multivariate Program (CLAMP). The latter produced the following parameters: mean annual temperature (MAT) from 17.2 to 17.7°C; warmest month mean temperature (WMMT) from 25 to 25.5°C; coldest month mean temperature (CMMT) from 9.5 to 10.8°C; length of growing season (GRS) from 9.5 to 9.7 months; growing season precipitation (GSP) from 1834.3 to 1901.2 mm; mean monthly growing season precipitation (MMGSP) from 222.4 to …


Silurian Graptolite, Conodont And Cryptospore Biostratigraphy Of The Gülüç Section In Ereğli, Zonguldak Terrane, Nw Anatolia, Turkey, Valeri Sachanski, Mehmet Cemal Göncüoğlu, Iskra Lakova, Ilina Boncheva, Gülnur Saydam-Demi̇ray Jan 2012

Silurian Graptolite, Conodont And Cryptospore Biostratigraphy Of The Gülüç Section In Ereğli, Zonguldak Terrane, Nw Anatolia, Turkey, Valeri Sachanski, Mehmet Cemal Göncüoğlu, Iskra Lakova, Ilina Boncheva, Gülnur Saydam-Demi̇ray

Turkish Journal of Earth Sciences

The studied Gülüç section of the Silurian Fındıklı Formation is situated on the western bank of Gülüç Creek in Ereğli, NW Anatolia, Turkey, in the eastern part of the Zonguldak Terrane. The Gülüç section consists of 3 sedimentary packages: greenish grey limy siltstones, 5-7 m thick (1), overlain by an irregular alternation of black shales and clayey limestones, about 15 m thick (2), and a 6-7 m thick succession of mainly siltstones and sandy limestones (3). A combined biostratigraphy based upon graptolites, cryptospores and conodonts indicates that Package 1 is of Llandovery (Rhuddanian, Aeronian and/or early Telychian) age, Package 2 …


Neotectonic Evolution Of An Actively Growing Superimposed Basin In Western Anatolia: The Inner Bay Of İzmir, Turkey, Bora Uzel, Hasan Sözbi̇li̇r, Çağlar Özkaymak Jan 2012

Neotectonic Evolution Of An Actively Growing Superimposed Basin In Western Anatolia: The Inner Bay Of İzmir, Turkey, Bora Uzel, Hasan Sözbi̇li̇r, Çağlar Özkaymak

Turkish Journal of Earth Sciences

İzmir Bay is an actively growing shallow marine basin controlled by active faults trending NE, NW, N-S and E-W, in the West Anatolian Extensional Province. The bay of İzmir is a lazy L-shaped superimposed basin which is topographically divided into an E-W-trending inner bay and a NW-trending outer bay. The Inner Bay of İzmir is an asymmetric graben structure approximately 5-7 km wide and 25 km long containing (i) upper Cretaceous-Palaeocene basement, (ii) an older succession of lower to upper Miocene basin fill, overlain with angular unconformity by (iii) a younger Plio-Quaternary basin fill. The older succession contain a 0.5- …


Stratigraphy And Some Structural Features Of The İstanbul Paleozoic, Necdet Özgül Jan 2012

Stratigraphy And Some Structural Features Of The İstanbul Paleozoic, Necdet Özgül

Turkish Journal of Earth Sciences

Palaeozoic rocks crop out across large areas in the İstanbul region. The Palaeozoic sequence starts with the Lower Ordovician fluviatile and lacustrine deposits (Kocatöngel and Kurtköy formations). The area was transgressed by the sea during the Late Ordovician-Early Silurian, represented by the feldspathic quartzwacke and quartz-arenites of the Kınalıada and Aydos formations. The basin became progressively deeper and more stable during the Silurian and Devonian. In this period, micaceous siltstones and sandstones of the Yayalar Formation (Upper Ordovician (?)-Lower Silurian), shelf-type carbonates of the Pelitli Formation (Lower Silurian-Lower Devonian), fossil-rich micaceous shales with rare limestone intercalations representing a low-energy open …


An Active Composite Pull-Apart Basin Within The Central Part Of The North Anatolian Fault System: The Merzifon-Suluova Basin, Turkey, Fuat Bora Rojay, Ali̇ Koçyi̇ği̇t Jan 2012

An Active Composite Pull-Apart Basin Within The Central Part Of The North Anatolian Fault System: The Merzifon-Suluova Basin, Turkey, Fuat Bora Rojay, Ali̇ Koçyi̇ği̇t

Turkish Journal of Earth Sciences

The North Anatolian Fault System (NAFS) that separates the Eurasian plate in the north from the Anatolian microplate in the south is an intracontinental transform plate boundary. Its course makes a northward convex arch-shaped pattern by flexure in its central part between Ladik in the east and Kargı in the west. A number of strike-slip basins of dissimilar type and age occur within the NAFS. One of the spatially large basins is the E-W-trending Merzifon-Suluova basin (MS basin), about 55 km long and 22 km wide, located on the southern inner side of the northerly-convex section of the NAFS. The …


Late Cretaceous-Eocene Geological Evolution Of The Pontides Based On New Stratigraphic And Palaeontologic Data Between The Black Sea Coast And Bursa (Nw Turkey), Zahi̇de Özcan, Aral Okay, Ercan Özcan, Aynur Hakyemez, Sevi̇nç Altiner Jan 2012

Late Cretaceous-Eocene Geological Evolution Of The Pontides Based On New Stratigraphic And Palaeontologic Data Between The Black Sea Coast And Bursa (Nw Turkey), Zahi̇de Özcan, Aral Okay, Ercan Özcan, Aynur Hakyemez, Sevi̇nç Altiner

Turkish Journal of Earth Sciences

The Late Cretaceous-Eocene geological evolution of northwest Turkey between the Black Sea and Bursa was studied through detailed biostratigraphic characterization of eleven stratigraphic sections. The Upper Cretaceous sequence in the region starts with a major marine transgression and lies unconformably on a basement of Palaeozoic and Triassic rocks in the north (İstanbul-type basement) and on metamorphic rocks and Jurassic sedimentary rocks in the south (Sakarya-type basement). Four megasequences have been differentiated in the Late Cretaceous-Eocene interval. The first one, of Turonian to Late Campanian age, is represented by volcanic and volcanoclastic rocks in the north along the Black Sea coast, …


Dating Subduction Events In East Anatolia, Turkey, Oberhaensli Roland, Bousquet Romain, Osman Candan, Aral Okay Jan 2012

Dating Subduction Events In East Anatolia, Turkey, Oberhaensli Roland, Bousquet Romain, Osman Candan, Aral Okay

Turkish Journal of Earth Sciences

Metamorphic studies in the cover sequences of the Bitlis complex allow the thermal evolution of the massif to be constrained using metamorphic index minerals. Regionally distributed metamorphic index minerals such as glaucophane, carpholite, relics of carpholite in chloritoid-bearing schists and pseudomorphs after aragonite in marbles record a LT-HP evolution. This demonstrates that the Bitlis complex was subducted and stacked to form a nappe complex during the closure of the Neo-Tethys. During late Cretaceous to Cenozoic evolution the Bitlis complex experienced peak metamorphism of 1.0-1.1 GPa at 350-400°C. During the retrograde evolution temperatures remained below 460°C. 39Ar/40Ar dating of white mica …


Al-In-Hornblende Thermobarometry And Sr-Nd-O-Pb Isotopic Compositions Of The Early Miocene Alaçam Granite In Nw Anatolia (Turkey), Altuğ Hasözbek, Burhan Erdoğan, Muharrem Satir, Wolfgang Siebel, Erhan Akay, Güllü Deni̇z Doğan, Heinrich Taubald Jan 2012

Al-In-Hornblende Thermobarometry And Sr-Nd-O-Pb Isotopic Compositions Of The Early Miocene Alaçam Granite In Nw Anatolia (Turkey), Altuğ Hasözbek, Burhan Erdoğan, Muharrem Satir, Wolfgang Siebel, Erhan Akay, Güllü Deni̇z Doğan, Heinrich Taubald

Turkish Journal of Earth Sciences

During and after the closure of the Neo-Tethyan Ocean and progressive collision of the Tauride-Anatolide Platform with the Sakarya Continent, widespread magmatism occurred in NW Anatolia. This magmatism is manifested in a NW-trending belt along the northern border of the Menderes Massif. Due to the complex geodynamic setting of this region, the exact emplacement depth of the granitoids is still a matter of debate. Here we present Al-in-hornblende barometrical data and Sr-Nd-Pb isotope compositions of the Early Miocene Alaçam granite. The results imply a shallow emplacement depth of this granite (4.7±1.6 km) in contrast to previous studies which suggested emplacement …


Discovery Of A Mississippian Reef In Turkey: The Upper Viséan Microbial-Sponge-Bryozoan-Coral Bioherm From Kongul Yayla (Taurides, S Turkey), Julien Denayer, Markus Aretz Jan 2012

Discovery Of A Mississippian Reef In Turkey: The Upper Viséan Microbial-Sponge-Bryozoan-Coral Bioherm From Kongul Yayla (Taurides, S Turkey), Julien Denayer, Markus Aretz

Turkish Journal of Earth Sciences

For the first time, a Mississippian reef is described from Turkey. This microbial-sponge-bryozoan-coral bioherm has been discovered in the Central Taurides (South Turkey), at Kongul Yayla located between Hadim and Taşkent. The bioherm contains a rich and diversified fauna: sponges and rugose corals are of particular interest. The bioherm shows four main facies reflecting distinct growth stages from the base to the top: (1) the basal bioclastic beds, (2) the core facies formed of framestone comprising rugose corals, lithistid sponges, fistuliporid bryozoans and microbial boundstone, (3) the crest facies with large colonies of cerioid rugose corals and chaetetid sponges, and …


The Unaz Formation: A Key Unit In The Western Black Sea Region, N Turkey, Okan Tüysüz, İsmai̇l Ömer Yilmaz, Lilian Svabenicka, Sabri̇ Ki̇ri̇ci̇ Jan 2012

The Unaz Formation: A Key Unit In The Western Black Sea Region, N Turkey, Okan Tüysüz, İsmai̇l Ömer Yilmaz, Lilian Svabenicka, Sabri̇ Ki̇ri̇ci̇

Turkish Journal of Earth Sciences

The Pontide magmatic belt in the Western Pontides, which developed in response to the northward subduction of the northern branches of the Tethys Ocean, consists of two different volcanic successions separated by an Upper Santonian pelagic limestone unit, the Unaz Formation. The first period of volcanism and associated sedimentation started during the Middle Turonian and lasted until the Early Santonian under the control of an extensional tectonic regime, which created horst-graben topography along the southern Black Sea region. The lower volcanic succession, the Dereköy Formation, was deposited mainly within these grabens. This extensional period probably represents the rifting of magmatic …


Late Miocene Palaeoclimate And Ecosystem Dynamics In Southwestern Bulgaria − A Study Based On Pollen Data From The Gotse-Delchev Basin, Dimiter A. Ivanov, Torsten Utescher, A. Rahman Ashraf, Volker Mosbrugger, Vladimir Bozukov, Nadezhda Djorgova, Evgenia Slavomirova Jan 2012

Late Miocene Palaeoclimate And Ecosystem Dynamics In Southwestern Bulgaria − A Study Based On Pollen Data From The Gotse-Delchev Basin, Dimiter A. Ivanov, Torsten Utescher, A. Rahman Ashraf, Volker Mosbrugger, Vladimir Bozukov, Nadezhda Djorgova, Evgenia Slavomirova

Turkish Journal of Earth Sciences

A profile 63 m thick in the Late Miocene in the Gotse-Dechev Basin (SW Bulgaria) was sampled for pollen analysis in the Kanina opencast mine. The exposed sequence comprises a basal unit with brown coal-clay cycles and clayey/siliciclastic cover layers partly representing a lacustrine facies. A total of 60 pollen samples were analysed, but quantitative data are confined to 30 polleniferous samples. The palynological analysis carried out provides data about the composition and structure of the fossil vegetation. The main vegetation type was a mixed mesophytic forest dominated by Carya, Fagus, Betula, Quercus, and Ulmus. Accessory elements included Magnolia, Corylopsis, …


Carbon Isotope And Stomatal Data Of Late Pliocene Betulaceae Leaves From Sw China: Implications For Palaeoatmospheric Co2-Levels, Bainian Sun, Suting Ding, Jingyu Wu, Chong Dong, Sanping Xie, Zhicheng Lin Jan 2012

Carbon Isotope And Stomatal Data Of Late Pliocene Betulaceae Leaves From Sw China: Implications For Palaeoatmospheric Co2-Levels, Bainian Sun, Suting Ding, Jingyu Wu, Chong Dong, Sanping Xie, Zhicheng Lin

Turkish Journal of Earth Sciences

The cuticular \delta^1^3C values and stomatal parameters (stomatal density and stomatal index: SD and SI) of two Betulaceae species, Betula mioluminifera Hu et Chaney and Carpinus miofangiana Nathorst, from a suite of superposed horizons in West Yunnan, southwestern China, were measured in order to recover Late Pliocene CO2 levels. Correlations are given for \delta^1^3C, SD, epidermal cell density (ECD), and SI. \delta^1^3C reveals a positive trend with the SD and SI in the two species, and such a positive correlation can also be observed between the \delta^1^3C and ECD in C. miofangiana. However, \delta^1^3C has a slightly negative correlation with …


Kinematics And Basin Formation Along The Ezinepazar-Sungurlu Fault Zone, Ne Anatolia, Turkey, Mehmet Korhan Erturaç, Okan Tüysüz Jan 2012

Kinematics And Basin Formation Along The Ezinepazar-Sungurlu Fault Zone, Ne Anatolia, Turkey, Mehmet Korhan Erturaç, Okan Tüysüz

Turkish Journal of Earth Sciences

The Ezinepazar-Sungurlu Fault (EzSF) is a major offshoot of the dextral North Anatolian Fault (NAF) zone, which bifurcates from the main fault strand around the Niksar pull-apart basin (37°E) and strikes through the Central Anatolian Block for 200 km to the west (34°E). The easternmost segment of the EzSF, the Ezinepazar Fault (EzF), which ruptured during the 1939 Erzincan earthquake (Mw= 7.8), has a very remarkable expression as a single-strand fault. Micromammal dating of young sediments along this segment indicate that the EzF was initiated during the Middle Pleistocene (0.7-1 Ma) and propagated westward accumulating 6.5±0.5 km maximum morphological offset. …


Geochemical And Isotopic Constraints On Petrogenesis Of The Beypazarı Granitoid, Nw Ankara, Western Central Anatolia, Turkey, Yeşi̇m Yücel Öztürk, Cahi̇t Helvaci, Muharrem Satir Jan 2012

Geochemical And Isotopic Constraints On Petrogenesis Of The Beypazarı Granitoid, Nw Ankara, Western Central Anatolia, Turkey, Yeşi̇m Yücel Öztürk, Cahi̇t Helvaci, Muharrem Satir

Turkish Journal of Earth Sciences

The Upper Cretaceous Beypazarı granitoid of the western Ankara, Turkey, is composed of two different units, on the basis of petrography and geochemical composition; these are granodiorite and diorite. The granitoid is subalkaline, belonging to the high-K calc-alkaline I-type granite series, which have relatively low initial 87Sr/86Sr ratios (0.7053-0.7070). All these characteristics, combined with major, trace element geochemical data as well as mineralogical and textural evidence, reveal that the Beypazarı granitoid formed in a volcanic arc setting and was derived from a subduction-modified and metasomatized mantle-sourced magma, with its crustal and mantle components contaminated by interaction with the upper crust. …


Chromite-Hosted Silicate Melt Inclusions From Basalts In The Stravaj Complex, Southern Mirdita Ophiolite Belt (Albania), Izabella Havancsàk, Friedrich Koller, Jànos Kodolànyi, Csaba Szabò, Volker Höck, Kujtim Onuzi Jan 2012

Chromite-Hosted Silicate Melt Inclusions From Basalts In The Stravaj Complex, Southern Mirdita Ophiolite Belt (Albania), Izabella Havancsàk, Friedrich Koller, Jànos Kodolànyi, Csaba Szabò, Volker Höck, Kujtim Onuzi

Turkish Journal of Earth Sciences

The Stravaj ophiolite compex, part of the western Mirdita ophiolite belt in Albania, is located east of the Shpati massif, and west of the Shebenik massif. The Stravaj ophiolite sequence itself consist of MOR-related and subduction-related volcanic rocks (Hoeck et al. 2007) formed by pillow lavas and various dykes. The deeper units are formed by gabbros and plagioclase-bearing peridotites. The pillow lavas are intersected by basaltic dykes with a rather primitive composition. The studied basaltic dyke contains former relics of olivine, fresh spinel and clinopyroxene phenocrysts in a glassy groundmass. The silicate phases are strongly altered. The spinels appear as …


Archaean Zircon U-Pb Age Paradox In Juvenile Neoproterozoic Granitoids, Central North Sudan, Saharan Metacraton, Shang Cosmas, Morteani Giulio, Muharrem Satir Jan 2012

Archaean Zircon U-Pb Age Paradox In Juvenile Neoproterozoic Granitoids, Central North Sudan, Saharan Metacraton, Shang Cosmas, Morteani Giulio, Muharrem Satir

Turkish Journal of Earth Sciences

It has long been shown that central North Sudan with its heterogeneous isotopic composition, unlike neighbouring Archaean cratons and the Neoproterozoic Arabian-Nubian Shield, is part of the Saharan metacratonic crust that was remobilized in the Neoproterozoic. In this paper, we report an Archaean zircon U-Pb age in the Saharan Metacraton that paradoxically does not indicate the presence of an Archaean crust. The second paradox concerns geochemical data that show Archaean tonalite-trondhjemite-granodiorite (TTG) features and also post-Archaean granitoid features, yet the rocks are Neoproterozoic. The granitoids studied are from north of Delgo in the Halfa terrane. They are calc-alkaline and meta- …


Palaeoflora And Climate Of Lignite-Bearing Lower−Middle Miocene Sediments In The Seyitömer And Tunçbilek Sub-Basins, Kütahya Province, Northwest Turkey, Mehmet Serkan Akki̇raz, Funda Akgün, Torsten Utescher, Volker Wilde, Angela Anneliese Bruch, Volker Mosbrugger, Sari̇ye Duygu Üçbaş Jan 2012

Palaeoflora And Climate Of Lignite-Bearing Lower−Middle Miocene Sediments In The Seyitömer And Tunçbilek Sub-Basins, Kütahya Province, Northwest Turkey, Mehmet Serkan Akki̇raz, Funda Akgün, Torsten Utescher, Volker Wilde, Angela Anneliese Bruch, Volker Mosbrugger, Sari̇ye Duygu Üçbaş

Turkish Journal of Earth Sciences

Lower-Middle Miocene successions from Kütahya province (Seyitömer and Tunçbilek sub-basins) were analyzed to reconstruct the palaeoclimate and vegetation of the period. A rich coniferous forest formed the dominant components among sporomorphs and consisted mainly of undeterminable Pinaceae, Pinus haploxylon type, Pinus diploxylon type, Picea, Cedrus, Cathaya, Keteleeria and Podocarpus. Pollen data also indicate the presence of some fern taxa (Osmunda, Polypodiaceae, Schizeaceae) Selaginella and Lycopodium. Cupressaceae frequently occur in all samples from both sub-basins, and form part of the mixed forest assemblage. Two woody plants Castanea-Castanopsis and evergreen Quercus predominate in the assemblages as well. The reconstruction of palaeoclimate is …


Sedimentary Properties Of The Middle−Upper Eocene Formations In Çardak, Burdur And İncesu, Sw Turkey, Ezher Toker, Mehmet Serkan Akki̇raz, Fuzuli̇ Yağmurlu, Funda Akgün, Sefer Örçen Jan 2012

Sedimentary Properties Of The Middle−Upper Eocene Formations In Çardak, Burdur And İncesu, Sw Turkey, Ezher Toker, Mehmet Serkan Akki̇raz, Fuzuli̇ Yağmurlu, Funda Akgün, Sefer Örçen

Turkish Journal of Earth Sciences

The integration of sedimentological, palynological and palaeontological data in three different outcrops in SW Turkey provides a clearer understanding of the palaeoenvironments in an area between the Çardak-Dazkırı Basin and the Isparta region during the Middle-Late Eocene. In this study, the Çardak-Dazkırı (Başçeşme Formation), Burdur (Varsakyayla Formation) and Isparta (Kayıköy Formation) areas have been studied for facies and facies associations. These formations contain alluvial fan, fan delta, shelf and related marine deposits. Detailed field observations allowed 34 lithofacies and 10 facies associations to be identified. The palynomorph assemblages in the Başçeşme and Varsakyayla formations contain biostratigraphically important taxa such as …


The Palu-Uluova Strike-Slip Basin In The East Anatolian Fault System, Turkey: Its Transition From The Palaeotectonic To Neotectonic Stage, Serap Çolak, Ercan Aksoy, Ali̇ Koçyi̇ği̇t, Murat İnceöz Jan 2012

The Palu-Uluova Strike-Slip Basin In The East Anatolian Fault System, Turkey: Its Transition From The Palaeotectonic To Neotectonic Stage, Serap Çolak, Ercan Aksoy, Ali̇ Koçyi̇ği̇t, Murat İnceöz

Turkish Journal of Earth Sciences

The East Anatolian fault system (EAFS) is the 80-km-wide, 700-km-long, NE-trending sinistral strike-slip fault system forming a seismically very active intracontinental transfom fault boundary. It is located between Karlıova County in the northeast and Karataş-Samandağ counties in the southwest, and forms the southeastern boundary of the Anatolian platelet. The Palu-Uluova basin is one of several strike-slip basins located along the EAFS. It is surrounded by several push-ups such as the Karaömerdağı, Mastardağı and Askerdağı push-ups caused by the complexities peculiar to strike-slip faulting. The Palu-Uluova basin consists of three sub-sections: two are NE-trending strike-slip sub-basins, the Uluova and the Palu-Kumyazı …


Testing Alternative Tectono-Stratigraphic Interpretations Of The Late Palaeozoic−Early Mesozoic Karakaya Complex In Nw Turkey: Support For An Accretionary Origin Related To Northward Subduction Of Palaeotethys, Alastair Robertson, Ti̇mur Ustaömer Jan 2012

Testing Alternative Tectono-Stratigraphic Interpretations Of The Late Palaeozoic−Early Mesozoic Karakaya Complex In Nw Turkey: Support For An Accretionary Origin Related To Northward Subduction Of Palaeotethys, Alastair Robertson, Ti̇mur Ustaömer

Turkish Journal of Earth Sciences

Lower Carboniferous-Upper Triassic rocks of the Karakaya Complex exposed E-W across Turkey are critical to reconstructions of Palaeotethys in the Eastern Mediterranean region. Despite decades of research, the origin and emplacement of the Karakaya Complex remains controversial because it is mapped either as an overall stratigraphic succession of sedimentary olistostromes or as a stack of thrust sheets and mélange. Tectonic models include a continental rift, a back-arc rift, a marginal oceanic basin, and an accretionary prism formed by subduction of a wide ocean. Subduction is seen as either northwards or southwards. To test the alternatives, the various litho-tectonic units and …


Stable Isotope Composition Of Hydrothermally Altered Rocks And Hydrothermal Minerals At The Los Azufres Geothermal Field, Mexico, Ignacio S Torres Alvarado, Muharrem Satir, Daniel Perez Zarate, Peter Birkle Jan 2012

Stable Isotope Composition Of Hydrothermally Altered Rocks And Hydrothermal Minerals At The Los Azufres Geothermal Field, Mexico, Ignacio S Torres Alvarado, Muharrem Satir, Daniel Perez Zarate, Peter Birkle

Turkish Journal of Earth Sciences

The Los Azufres geothermal field is the second most important geothermal field for electricity production in Mexico, with a total installed capacity of 188 MW. Hydrothermal alteration studies have been an important tool for geothermal exploration and development of the field, but little attention has been given to the geochemical and isotopic characterization of hydrothermal minerals. \delta^1^8O, \delta^2H, and \delta^1^3C systematics at Los Azufres geothermal field were investigated using whole rock samples, as well as hydrothermal minerals separates, obtained from different depths in the wells Az-26 and Az-52. Most \delta^1^8O values reproduce well the present in-situ field temperatures and isotopic …


The Early−Middle Palaeozoic Oceanic Events Along The Southern European Margin: The Deli Jovan Ophiolite Massif (Ne Serbia) And Palaeo-Oceanic Zones Of The Great Caucasus, Guram Zakariadze, Stevan Karamata, Sergei Korikovsky, Aleksei Ariskin, Shota Adamia, Tamar Chkhotua, Sergei Sergeev, Natasha Solov'eva Jan 2012

The Early−Middle Palaeozoic Oceanic Events Along The Southern European Margin: The Deli Jovan Ophiolite Massif (Ne Serbia) And Palaeo-Oceanic Zones Of The Great Caucasus, Guram Zakariadze, Stevan Karamata, Sergei Korikovsky, Aleksei Ariskin, Shota Adamia, Tamar Chkhotua, Sergei Sergeev, Natasha Solov'eva

Turkish Journal of Earth Sciences

The paper deals with the Middle Palaeozoic oceanic events on the northern margin of the Eastern Mediterranean Hercynides. The Balkan-Carpathian Ophiolite Belt (BCO) and palaeo-oceanic zones of the Great Caucasus, all framing the East European Platform from the south, are correlated. The BCO palaeo-oceanic complex was widely thought to be a Late Precambrian-earliest Cambrian oceanic thrust sheet (563±5 Ma), a part of the South European Palaeo-oceanic Suture. The geochronological studies carried out on gabbroic series of the Deli Jovan Massif (BCO, NE Serbia), showed, however, that they are of much younger (Early Devonian) age: (a) Sm-Nd mineral isochron age of …


Geology And Hydrocarbon Systems In The Western Black Sea, Georgi Georgiev Jan 2012

Geology And Hydrocarbon Systems In The Western Black Sea, Georgi Georgiev

Turkish Journal of Earth Sciences

This paper presents the author's integrated regional studies during the last decade. The main purpose is to present an overall understanding of the geological structure, sedimentary basins and hydrocarbon systems of the whole Western Black Sea Zone (WBSZ). This study is based on original data from boreholes, seismic and gravity-magnetic surveys and hydrocarbon accumulations. Many geophysical borehole data obtained for WBSZ during the last 3-4 decades were interpreted mostly at a national level using different approaches, terminology and nomenclature for the same or similar lithostratigraphic and tectonic units. Therefore, a unified approach to interpretation of borehole-seismic data and correlation of …


Palaeozoic Formations From Dobrogea And Pre-Dobrogea – An Overview, Antoneta Seghedi Jan 2012

Palaeozoic Formations From Dobrogea And Pre-Dobrogea – An Overview, Antoneta Seghedi

Turkish Journal of Earth Sciences

No abstract provided.


Late Palaeozoic To Cenozoic Evolution Of The Black Sea-Southern Eastern Europe Region: A View From The Russian Platform, Anatoly Nikishin, Peter Ziegler, Sergey Bolotov, Pavel Fokin Jan 2012

Late Palaeozoic To Cenozoic Evolution Of The Black Sea-Southern Eastern Europe Region: A View From The Russian Platform, Anatoly Nikishin, Peter Ziegler, Sergey Bolotov, Pavel Fokin

Turkish Journal of Earth Sciences

A synthesis of the Late Palaeozoic to Cenozoic evolution of the Black Sea region and the southern parts of the East European Platform (EEP) is presented. During Carboniferous to Early Permian times the Cordillera-type Euxinus Orogen evolved along the southern margin of the EEP in response to progressive closure of the Rheic and Palaeotethys oceans and the accretion of Gondwana-derived continental terranes. Permian development of the north-dipping Palaeotethys subduction system along the southern Pontides margin of these terranes was accompanied by important compressional intraplate deformation on the EEP. The Mesozoic to Palaeogene evolution of the southern parts of the EEP, …