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Koleksiyondaki öğeler
- MakaleAçık Erişim2024Does structural change matter for sustainable development in newly industrialized countries? Fresh evidence from a new sustainability indicator
Artan, Seyfettin; Erdogan, Sinan; Recepoglu, Muersit; Çakir, Suemeyra cay; Hayaloglu, Pinar; Çakir, Mehmet Ali
The economic gap between developed and developing economies has been diminishing due to the recent rapid economic growth performance of developing economies. While achieving this swift growth level, developing economies have structurally transformed their economies. However, the impact of this structural change on environmental sustainability remains unclear. Therefore, this study focuses on the impacts of structural change, energy structure, and economic growth on the load capacity factor, a comprehensive sustainability indicator, in newly industrialized countries during 2000-2020. To this end, second-generation panel data techniques, which account for cross-sectional dependence and heterogeneity, are used to provide more robust and reliable estimates. The results show that economic growth, structural change, and fossil energy utilization decrease the load capacity factor while renewable energy utilization increases it. These findings underscore the need for energy efficiency and resource-conscious policies that align with environmental sustainability while promoting economic growth, highlighting their crucial role in the future of sustainable development.
- MakaleYalnız künye20263-D magnetotelluric modeling and radiogenic heat reservoir for EGS development: A case study of the Kestanbol Granitoid intrusion (NW Türkiye)
Büyük, Ersin; Hacioglu, Ozlem; Ayzit, Tolga; Baba, Alper
Enhanced Geothermal Systems (EGS) provide firm, low-carbon baseload power and can contribute to reducing fossil-fuel-based energy generation. Granites and granitoids are particularly favourable EGS hosts due to their widespread occurrence, fracture-controlled permeability, and long-term heat supply from radiogenic decay. This study proposes an EGS development plan for the Kestanbol Granitoid Intrusion (KGI) in NW Anatolia, T & uuml;rkiye, based on a three-dimensional magnetotelluric (MT) model integrated with geochemical constraints on radiogenic heat production (RHP). We invert MT data acquired at fifty unevenly spaced sites to image the 3D resistivity structure of the KGI and its surroundings, resolving a highly resistive plutonic body bounded by relatively conductive fault-fracture zones. To quantify the radiogenic heat reservoir, we determine RHP rates from uranium, thorium, and potassium concentrations measured on twenty-seven rock samples from the KGI and adjacent lithologies, and integrate these values with the MT-derived pluton geometry. When combined with the regional stress regime, the integrated results indicate that the KGI hosts elevated RHP relative to surrounding rocks and that its internal structure and fault-controlled permeability architecture are favourable for EGS development. In particular, the north-western margin of the KGI emerges as the most promising target for injection-production well pairs. This workflow demonstrates how integrated MT, geochemical, and structural analyses can provide a quantitative, site-specific basis for EGS prospect ranking and drilling strategy in radiogenic granite/granitoid provinces. Overall, we propose a site-specific and risk-aware EGS development plan for the KGI that couples subsurface structure, radiogenic heat supply, and permeability architecture, providing a transferable framework for assessing radiogenic granite/granitoid provinces.
- MakaleAçık Erişim2017Synthesis of some natural sulphonamide derivatives as carbonic anhydrase inhibitors
Gokcen, Taner; Al, Melike; Topal, Meryem; Gulcin, Ilhami; Ozturk, Turan; Goren, Ahmet C.
Carbonic anhydrase inhibitor; sulphonamides; p-hydroxybenzoic acid; 3,4,5-trihydroxybenzoic acid (gallic acid).Carbonic anhydrase inhibitors are both in clinical use as antiglaucoma, diuretics, antiepileptics and management of altitude sickness, and under investigation as anticancer, anticonvulsant and antiobesity agents. Sulphonamides have been known for decades as carbonic anhydrase inhibitors and are in clinical use. Sulphonamide derivatives of p-hydroxybenzoic acid and 3,4,5-trihydroxybenzoic acid (gallic acid) were synthesized and their inhibition values over hCA I and hCA II isozymes, purified from human erythrocyte cells by Sepharose-4B-L-tyrosine-sulphanilamide, were determined. Compounds synthesized showed efficient carbonic anhydrase inhibition activity at low nM levels.
- MakaleAçık Erişim2017Synthesis, in vitro DNA interactions, cytotoxicities, antioxidative activities, and topoisomerase inhibition potentials of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes with azo-oxime ligands
Ayvaz, Melekcol; Turan, Ibrahim; Dural, Bayram; Demir, Selim; Karaoglu, Kaan; Aliyazicioglu, Yuksel; Serbest, Kerim
Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) transition metal complexes of 2-hydroxy-5-[(E)-(4-phenyl) diazenyl] benzaldehyde oxime and 2-hydroxy-5-[(E)-(4-nitrophenyl) diazenyl] benzaldehyde oxime ligands were synthesized and characterized through NMR, IR, ESI mass, and UV analysis. DNA binding abilities of the complexes were revealed using a UV-Vis spectrophotometer with the absorption titration and competitive binding techniques. Hydrolytic and oxidative DNA cleavage activities under different conditions were also proved. Topoisomerase I inhibition efficiencies and in vitro free radical scavenging activities of all complexes were examined. Finally, the selective cytotoxic potentials of all complexes were evaluated in human colon cancer, normal colon, and fibroblast cell lines using the water-soluble tetrazolium salt (WST-1) assay. The complexes had the ability to intercalate into stacked base pairs of DNA and topoisomerase I activity was reasonably inhibited in their presence in 0.4 mM concentrations. The abilities for scavenging of DPPH and hydroxyl radicals were found to be higher than those of known standard antioxidants (ascorbic acid, butylated hydroxyanisole, and mannitol). The results obtained from the cytotoxicity experiments are especially promising for further research, which must be carried out for the evaluation of the studied complexes as anticancer drugs.
- MakaleAçık Erişim2024Role of culture and religious beliefs on non-medical help-seeking behavior among patients with chronic mental illnesses (CMIs) in Türkiye
Ediz, Cicek; Uzun, Sevda; Mohammadnezhad, Masoud; Erdas, Mehmed B.
Background:Cultural beliefs significantly shape societal attitudes toward mental illness, and these social attitudes profoundly impact help-seeking behaviors. Therefore, it is important to focus on understanding and addressing these social behaviors.Aim:This study aimed to evaluate the effect of chronic mental illness interpretations based on culture and religious beliefs on non-medical help-seeking behaviors among patients in T & uuml;rkiye.Methods:The study was conducted from September to October 2023 using an inductive qualitative approach. In-depth face-to-face interviews were carried out with individuals diagnosed with chronic mental illness and their relatives, registered in a state-owned Community Mental Health Center (CMHC) in T & uuml;rkiye. Using purposive sampling, 13 individuals who met the criteria were interviewed. Thematic analysis was used to identify themes.Results:Three main themes and eight sub-themes were identified, including the reasons for seeking non-medical help (psychological challenges, subjective norms, physical requirements), factors contributing to seeking non-medical help (predisposing factors, enabling factors, and myths), and reflections on the benefits of non-medical practices (perceived physical benefits, perceived psychological benefits).Conclusions:It was concluded that individuals with chronic mental illness and their relatives living in the Eastern Anatolia Region of T & uuml;rkiye engaged in non-medical help-seeking behaviors and mostly turned to traditional religious practices. Culture and religious beliefs emerged as primary factors leading patients to seek non-medical treatment approaches. Consequently, there is a perceived need to explore non-medical alternative methods across various mental health settings and with diverse samples in future research endeavors.
- DüzeltmeAçık Erişim2025Discontinuity characterization for slope stability assessment using combined aerial photogrammetry, and geophysics approach (Oct, 10.1007/s11069-024-06932-3, 2024)
Junaid, Muhammad; Abdullah, Rini Asnida; Ullah, Arshad; Sa'ari, Radzuan; Mahmood, Sajid; Rehman, Hafeezur; Rehman, Safi ur; Sari, Mahmut
In this article the author’s name Mahmut Sari was incorrectly written as Mahmut Saari. The original article has been corrected.
- MakaleYalnız künye2013Cadmium and nickel determinations in some food and water samples by the combination of carrier element-free coprecipitation and flame atomic absorption spectrometry
Bahadir, Zekeriyya; Ozdes, Duygu; Bulut, Volkan Numan; Duran, Celal; Elvan, Hamide; Bektas, Hakan; Soylak, Mustafa
A procedure for separation and enrichment of Cd(II) and Ni(II) ions based upon carrier element-free coprecipitation by using an organic coprecipitant, 2-{4-[2-(1H-Indol-3-yl)ethyl]-3-(4-methylbenzyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl}-N-(3-fluoro-phenylmethyliden) acetohydrazide, prior to their flame atomic absorption spectrometric detections has been developed. The effects of varied experimental conditions on the performance of the developed method such as pH, sample volume, amount of coprecipitating agent, etc. were evaluated in detail on the recovery of analyte ions, and the influences of some anions and cations were investigated. The limits of detection for Cd(II) and Ni(II) ions based on three times the standard deviation of the blanks (N: 10) were obtained as 0.70 g L-1 and 1.21 g L-1, respectively. The accuracy of the method was tested by analyzing a certified reference material and by spike tests. The method was applied to determine the levels of cadmium and nickel in stream and sea water, rice, red lentil, and wheat samples.
- MakaleYalnız künye2015The relationship between ischemia-modified albumin and myocardial infarction in on-pump coronary artery bypass grafting
Mentese, Umit; Dogan, Orhan Veli; Dogan, Suheyla; Turan, Ibrahim; Usta, Sefer; Demirbas, Mine; Aykan, Ahmet Cagri; Kiliç, Askin; Demir, Selim; Karahan, Suleyman Caner
Background: This study aims to evaluate the potential of ischemia-modified albumin (IMA) to predict the myocardial infarction in on pump coronary artery bypass grafting (ONCABG) patients. Methods: Fifty elective isolated ONCABG patients (41 males, 9 females; mean age 66 years; range 56 to 75 years) were included in the study. Patients were divided into perioperative myocardial infarction (PMI; n=8) and non-infarction (NPMI; n=42) groups according to perioperative cardiac troponin I (cTnI) values and ECG findings. Serum IMA levels were measured preoperatively, 20 minutes after aortic cross clamping, 30 minutes, at 3, 6, 12 and 24 hours after declamping. Results: Compared to the NPMI group, the declamping 30 minutes, 3, 6 and 12 hours IMA levels were higher in the PMI group (p=0.002, p=0.048, p=0.023, p=0.007, respectively). In both NPMI and PMI groups, the 20 minutes after aortic cross clamping IMA levels were higher compared to the preoperative IMA levels (p=0.0001, p=0.038, respectively). Conclusion: Our study results show that IMA may be an early marker of myocardial infarction in the ONCABG patients.
- Derleme MakaleAçık Erişim2018A REVIEW OF FLOW BOILING IN MINI AND MICROCHANNEL FOR ENHANCED GEOMETRIES
Çebi, Alican; Celen, Ali; Donmez, Aydin Haci; Karakoyun, Yakup; Celen, Pinar; Cellek, Mehmet Salih; Dalkiliç, Ahmet Selim; Taner, Tolga; Wongwises, Somchai
Flow boiling researches in enhanced geometries practiced recently have been summarized in this review. Classical approximations in macroscale flows have not applied to the flows with small hydraulic diameters, so, this subject has been paid attention by the researchers. Application areas of these structures are increasing continuously due to cooling need in small confined spaces. The related studies have been reviewed in a chronological manner and their parameters have been given in a table in order for the researchers to observe the scientific duration regarding the progresses on this subject. Almost all papers on this subject have been produced after 2000, therefore, this subject is considered as an actual one to improve and worth to study in the literature. This study can not only be evaluated as the beginning argument for the researchers involved in flow boiling process in mini and microchannel, but it also consists of new works on the investigated subject.
- MakaleAçık Erişim2021Adipokine, gut and thyroid hormone responses to probiotic application in chukar partridges (Alectoris chukar) exposed to heat stress
Bayraktar, Bulent; Tekce, Emre; Kaya, Hacer; Gürbüz, Ahmet Burak; Dirican, Ebubekir; Korkmaz, Serol; Atalay, Banu; Ülker, Ufuk
The aim of this study was to investigate the effect of Lactobacillus reuteri E81 (LRE) probiotic supplementation on heat stress responses in chukar partridges (Alectoris chukar). The birds were divided into two groups, one of which was exposed to heat stress (HS). Within each group, four subgroups, each including 64 birds, were created for the three treatment doses (200, 400 or 600 mg/kg) of LRE and the control. The experiment was started with day-old birds, kept at a temperature of 25 degrees C or 37 degrees C. After a 7-day adjustment period, the LRE supplementation lasted for 35 days. The levels of different adipokines, including visfatin (VF), adiponectin (ADP), chemerin (CHEM), as well as the concentration of plasma citrulline (CIT) and the levels of thyroid hormones (T3 and T4) and thyroid-stimulating hormone (TSH) in the blood were measured at 21 and 42 days of age. A significant correlation (P < 0.01) was found between LRE supplementation and the decrease in serum VF, ADP, CIT, T3 and T4 levels in partridges exposed to HS. On the other hand, no significant relationship was found between LRE supplementation and the serum CHEM and TSH levels (P > 0.05). We concluded that the addition of 600 mg/kg LRE is beneficial in preventing intestinal damage and inflammation provoked by HS.
- MakaleYalnız künye2026Ramifications of Türkiye's public engagement with polar regions
Limon, Onur; Caymaz, Ebru; Gurdal Limon, Elif; Demirayak, Ozgur; Dal, Adnan; Özsoy, Burcu
This study examines how T & uuml;rkiye's National Polar Science Programme (NPSP) and the National Polar Science Symposium (NPSS) define and implement public engagement within the country's emerging polar research framework. Situating T & uuml;rkiye's experience within broader international debates on public engagement in emerging and internationally governed scientific domains, the analysis draws on core science communication theories, including deficit-dialogue-participation models, typologies of public engagement, and co-production perspectives. Methodologically, the study employs qualitative document analysis of ten NPSP Monitoring and Assessment Reports (2018-2022) and seven NPSS abstract books (2017-2023), using an iterative and theory-informed coding process. The findings indicate that public engagement is predominantly shaped by informational and visibility-oriented strategies, while dialogic elements are gradually emerging through education- and youth-focused initiatives. However, institutionalised participatory mechanisms enabling public influence on research agendas remain limited. The study concludes that T & uuml;rkiye's public engagement trajectory reflects a hybrid and incremental configuration shaped by institutional development within an internationally governed research context. By treating the Turkish case as an analytically comparative example rather than a context-specific exception, the article contributes to international discussions on how public engagement is structured and institutionalised in emerging polar and climate research programmes.
- MakaleYalnız künye2014The Eastern Black Sea-type volcanogenic massive sulfide deposits: Geochemistry, zircon U-Pb geochronology and an overview of the geodynamics of ore genesis
Eyuboglu, Yener; Santosh, M.; Yi, Keewook; Tuysuz, Necati; Korkmaz, Sadettin; Akaryali, Enver; Dudas, Francis O.; Bektas, Osman
The Meso-Cenozoic geodynamic evolution of the eastern Pontides orogenic belt provides a key to evaluate the volcanogenic massive sulfide (VMS) deposits associated with convergent margin tectonics in a Cordilleran-type orogenic belt. Here we present new geological, geochemical and zircon U-Pb geochronological data, and attempt to characterize the metallogeny through a comprehensive overview of the important VMS mineralizations in the belt. The VMS deposits in the northern part of the eastern Pontides orogenic belt occur in two different stratigraphic horizons consisting mainly of felsic volcanic rocks within the late Cretaceous sequence. SHRIMP zircon U-Pb analyses from ore-bearing dacites yield weighted mean Pb-206/U-238 ages ranging between 91.1 +/- 1.3 and 82.6 +/- 1 Ma. The felsic rocks of first and second horizons reveal geochemical characteristics of subduction-related calc-alkaline and shoshonitic magmas, respectively, in continental arcs and represent the immature and mature stages of a late Cretaceous magmatic arc. The nature of the late Cretaceous magmatism in the northern part of the eastern Pontides orogenic belt and the various lithological associations including volcaniclastics, mudstones and sedimentary facies indicate a rift-related environment where dacitic volcanism was predominant. The eastern Pontides VMS deposits are located within the caldera-like depressions and are closely associated with dome-like structures of felsic magmas, with their distribution controlled by fracture systems. Based on a detailed analyses of the geological, geophysical and geodynamic information, we propose that the VMS deposits were generated either in intra arc or near arc region of the eastern Pontides orogenic belt during the southward subduction of the Tethys oceanic lithosphere. (C) 2013 Elsevier B.V. All rights reserved.
- MakaleAçık Erişim2025The acute effect of neuromuscular electrical stimulation on optimum power performance in healthy individuals
Can, Ibrahim; Yerlikaya, Gokhan; Bayrakdaroglu, Serdar; Ceylan, Halil Ibrahim; Subak, Guelhan Erdem; Bayrakdaroglu, Yesim; Uluç, Sinem; Nikolaidis, Pantelis T.
Background: This study examines the acute effects of neuromuscular electrical stimulation (NMES) application on peak power (PP) and mean propulsive power (MPP) during a weighted squat jump (SJ(Loaded)). Methods: Fourteen male students (age: 23.71 +/- 2.30 years; height: 173.71 +/- 6.89 cm; weight: 69.59 +/- 9.08 kg; body mass index (BMI): 26.87 +/- 3.49) from the Faculty of Sport Sciences participated voluntarily. PP and MPP values were measured during the SJ(Loaded) movement, performed with an external load of 40% body weight, using a computer-integrated linear velocity transducer system (T-Force Dynamic Measurement System Ergotech Consulting SL, Murcia, Spain). NMES was bilaterally applied to the musculus hamstring and musculus quadriceps femoris for 20 minutes. The Shapiro-Wilk test, skewness and kurtosis values assessed data normality. Results: Differences between pre- and post-test PP and MPP power performances were analyzed using Paired Samples t-tests. Cohen's d (ES: effect size) and 95% confidence intervals (CI) were also calculated to assess the pairwise comparisons' magnitude. According to the analysis results, statistically significant improvements were observed in both PP (t (13) = -2.612, p = 0.021, d: -0.69 (-1.27; -0.10, 95% CI)) and MPP (t (13) = -2.756, p = 0.016, d: -0.73 (-1.32; -0.13, 95% CI), moderate effect) values after the NMES application. Conclusions: NMES significantly enhances PP and MPP during loaded squat jumps, highlighting its potential as a supplementary training tool for improving explosive power. Future studies should explore its long-term effects across different sports and populations, such as female athletes or older adults, to optimize training protocols. Research on NMES intensities and frequencies may provide insights into optimal parameters for power development and neuromuscular adaptation.
- MakaleYalnız künye2026Polar science diplomacy of Türkiye: the Second International Polar Year case
Limon, Onur; Gurdal Limon, Elif; Caymaz, Ebru; Demirayak, Ozgur; Dal, Adnan; Özsoy, Burcu
This article examines T & uuml;rkiye's participation in the Second International Polar Year (IPY-II, 1932-1933) as a historically grounded and underexplored case of early science diplomacy. IPY-II coordinated interdisciplinary polar research across forty-four countries, and T & uuml;rkiye's involvement during the early Republican period offers fresh insight into interwar scientific cooperation. The article documents T & uuml;rkiye's scientific and institutional contributions and analyses them through the reciprocal framework of science impacting diplomacy and diplomacy impacting science. Drawing on archival documents, official correspondence, parliamentary records, and contemporary newspapers, supplemented by expert interviews, it assesses the case against an explicit definition of science diplomacy. T & uuml;rkiye's meteorological data, later incorporated into the synoptic weather maps of the Northern Hemisphere, were scientifically significant, institutionally coordinated, and internationally recognised, yet shaped by asymmetrical hierarchies. The case enriches the historical understanding of science diplomacy by non-hegemonic states.
- MakaleAçık Erişim2012Adaptive multi-step differential transformation method to solving nonlinear differential equations
Gökdogan, Ahmet; Merdan, Mehmet; Yildirim, Ahmet
In this paper, we propose a fast and effective adaptive algorithm for the multi-step differential transformation method (MsDTM). This approach named as the adaptive MsDTM is applied to a number of nonlinear differential equations and numerical results are given. At the same time, a comparison between the MsDTM and the adaptive MsDTM reveals that the proposed approach is an efficiency tool for solving the considered equations using fewer time steps. (C) 2011 Elsevier Ltd. All rights reserved.
- MakaleAçık Erişim2017Accumulation of phenolics in natural and micropropagated plantlets of Thymus pseudopulegioides Klokov & Des.-Shost. with their antioxidant potentials
Günaydin, Mustafa; Laghari, Abdul Hafeez; Bektas, Ersan; Sökmen, Munevver; Sökmen, Atalay
Thymus pseudopulegioides plantlets were propagated in vitro via direct organogenesis by using Murashige and Skoog (MS) media containing kinetin, thidiazuron, and 6-benzyladenine (BA) individually. Methanol extracts obtained both from plantlets and wild plants were analyzed for their total phenolics and flavonoid contents, then quantified by HPLC. The highest total phenolic (8.83 mg/g as gallic acid equivalent) and total flavonoid (0.92 mg/mL as rutin equivalent) values were from the MS media supplemented with 1.0 mg/L kinetin and 0.5 mg/L BA, respectively. The plantlets grown in those media also showed remarkable antioxidant activities with an IC50 value of 4.77 mu g/mL in DPPH and 100% inhibition in beta-carotene assays, respectively. HPLC analysis proved the production of protocatechuic, caffeic, vanillic, rosmarinic, ferulic, and o-coumaric acids and rutin. Rosmarinic acid production was predominant in natural samples (115.2 mg/100 g dry weight), while the aforesaid phenolic acids were prevalent in plantlets grown on MS media supplemented with KIN or BA at various concentrations. Rutin production was the highest (50.74 mg/100 g dry weight) in the plantlets grown on MS medium containing kinetin (1.0 mg/L). As an economically important chemical, rosmarinic acid was selected as the target chemical and a novel method was introduced to achieve its selective isolation.
- MakaleYalnız künye2017Microindentation on the porous copper surface modulations
Ekmekci, Dursun; Yilmaz, Fikret; Kölemen, Ugur; Cora, Omer Necati
This study aimed to investigate the mechanical properties of a surface modulation which was realized through compaction, and then sintering of copper powders. To this goal, Berkovich type of indenter and depth-sensing indentation technique were used in microindentation to measure the hardness and modulus of elasticity values at different features of compact. Indentations were performed with a peak force of 50 mN. Hardness values were obtained in 0.88-1.12 GPa range while the modulus of elasticity was recorded in the 70-111 GPa interval. Even though both modulus of elasticity and hardness values were noted to be different for copper powders and substrate, one-way ANOVA analyses showed that the differences in both modulus of elasticity and hardness values are insignificant. FE modeling of microindentation was also performed and validated. It was shown that the force-displacement values obtained from FE analyses are quite well in agreement with the experimental data.
- MakaleYalnız künye2022The first record of Scapania cuspiduligera (Marchantiophyta: Scapaniaceae) in Turkish and Southwest Asia liverwort flora supported from molecular data
Batan, Nevzat; Vilnet, Anna; Abay, Gokhan; Erata, Huseyin; Özdemir, Turan
During the recent bryological excursion to the Rize region of Turkey, Scapania cuspiduligera has been collected, it is the first record of this species to Turkey and Southwest Asia. Brief description, illustration, ecological, ITS1-2 nrDNA and trnL-F cpDNA sequence data are provided and discussed.
- MakaleAçık Erişim2024Improved estimation of population variance in stratified successive sampling using calibrated weights under non-response
Pandey, M. K.; Singh, G. N.; Zaman, Tolga; Al Mutairi, Aned; Mustafa, Manahil SidAhmed
This paper introduces a new method to estimate the population variance of a study variable in stratified successive sampling over two occasions, while accounting for random non -response. The method uses a logarithmic type estimator and leverages information from a highly positively correlated auxiliary variable. The paper also presents calibrated weights for the new estimator and examines its properties through numerical and simulation studies. The results indicate that the suggested estimator is more effective than the standard estimator for estimating the population variance.
- MakaleYalnız künye2016Cenozoic forearc gabbros from the northern zone of the Eastern Pontides Orogenic Belt, NE Turkey: Implications for slab window magmatism and convergent margin tectonics
Eyuboglu, Yener; Dudas, Francis O.; Santosh, M.; Zhu, Di-Cheng; Yi, Keewook; Chatterjee, Nilanjan; Jeong, Youn-Joong; Akaryali, Enver; Liu, Ze
The Eastern Pontides Orogenic Belt represents one of the best examples of fossil convergent margins in the eastern Mediterranean region. However, the origin and geodynamic setting of the late Mesozoic-Cenozoic magmatism in this belt remain controversial due to lack of systematic geological, geochemical and chronological data. The general consensus is that the late Mesozoic-Cenozoic igneous activity is related to northward subduction of oceanic lithosphere in the late Mesozoic and following collision between Tauride and Pontide blocks in the early Cenozoic Here we present a comprehensive study focusing on the origin and geodynamic setting of gabbro bodies exposed along a narrow zone, parallel to the southeastern coast of the eastern Black Sea basin, in the Northern Zone of the Eastern Pontides Orogenic Belt. The studied gabbro bodies are hosted within late Cretaceous basaltic, andesitic, and dacitic volcanics including pyroclastic rocks and interbedded sedimentary rocks. The gabbro bodies range in size from 0.1 km(2) to 1.5 km(2), and outcrop patterns vary from round or elliptical to markedly elongate with sharp and discordant contact with the host rocks. Their mineral assemblage includes mainly clinopyroxene, plagioclase, minor olivine, amphibole, magnetite and rarely orthopyroxene, biotite, zircon and titanite. The occurrence of sutured grain boundaries on clinopyroxene and plagioclase, and the presence of reverse compositional zoning in clinopyroxene and olivine suggest mixing between magmas of contrasting compositions during mineral growth. Thermobarometric computations indicate that the temperature at the beginning of crystallization was similar to 1250 degrees C and crystallization was polybaric Zircon and titanite U-Pb ages indicate that these small intrusions were emplaced into crustal rocks of the Eastern Pontides Orogenic Belt during Lutetian (45 +/- 2 Ma). The depletion of HFSE is consistent with the involvement of an arc-related source in the petrogenesis of these rocks, and low to moderate enrichment Ce, Rb, Ba, K, Pb, Sr and Th suggests that involvement of subducted oceanic sediment was modest. The low Th content and low Th/Yb indicate that the role of sediment addition was nevertheless limited. The Nd, Sr and Pb isotopic data are consistent with the interpretation that the dominant source component in these gabbros is a depleted, peridotitic mantle, and that crustal contamination is relatively unimportant. We suggest that mafic magmas that produced the gabbroic intrusions were derived from melting of a depleted mantle source under the forearc region of the Eastern Pontides Orogenic Belt during southward subduction of two oceanic plates separated by a mid-ocean ridge, leading to the formation of a slab window. We also infer fractional crystallization and assimilation during both magma storage in the crust-mantle transition zone and transfer into the overlying arc crust. (C) 2015 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
