Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Kaygusuz, Abdullah(15)
- Kurt, Kemal(14)
- Sipahi, Ferkan(14)
- Yücel, Cem(9)
- Arslan, Mehmet(8)
- Akar, Bülent(7)
- Gücer, Mehmet Ali(6)
- Uzun, Sevda(6)
- Şahin, Bülent(6)
- Aslan, Zafer(5)
- Batan, Nevzat(5)
- Dokuz, Abdurrahman(5)
- Vural, Alaaddin(5)
- Erata, Hüseyin(4)
- Temizel, Irfan(4)
- Akpınar, İbrahim(3)
- Alataş, Mevlüt(3)
- Aydınçakır, Emre(3)
- Eyuboglu, Yener(3)
- Ezer, Tülay(3)
- Karsli, Orhan(3)
- Kulakaç, Nurşen(3)
- Sadiklar, M. Burhan(3)
- Saydam Eker, Çiğdem(3)
- Siebel, Wolfgang(3)
- Snegovaya, Nataly Yu.(3)
- Uysal, Ibrahim(3)
- Akpinar, A.(2)
- Akpinar, Adem(2)
- Aydinçakir, Emre(2)
- Barinova, Sophia(2)
- Bektas, Osman(2)
- Bilgic, Abdulbaki(2)
- Bostan, Sedat(2)
- Bölükbas, Mehmet(2)
- Chen, Bin(2)
- Coruh, Emine(2)
- Dervisoglu, Adalet(2)
- Dogan, Nilgun(2)
- Eker, Çiğdem Saydam(2)
Yayınlar
- MakaleYalnız künye2012Scopus SJRQ1Soil geochemical prospection for gold deposit in the Arzular area (NE Turkey)
Yaylali-Abanuz, Gülten; Tüysüz, Necati; Akaryali, Enver
The Arzular gold mineralization is located at the southern part of the Black Sea Tectonic Unit in northern Turkey. This belt hosts several high-potential epithermal gold deposits and it is highly probable that there are a number of undiscovered occurrences in the region. The presence of intensely altered areas, suitable structural elements and acidic intrusions indicates that the region has an important potential for epithermal gold. Soil geochemistry surveys are widely used for the exploration of buried mineral deposits. In this work the applicability of soil geochemistry surveys for exploration of buried mineral deposits was tested using various statistical methods. In this respect, concentrations of 16 elements have been assayed in about 50 soil samples collected from the Arzular area. Soil samples were taken from the B horizon. The data revealed elevated concentrations for gold (0.20-259.2 μg/kg), silver (23-26,972 μg/kg), arsenic (1.7-301.8. mg/kg), copper (54.09-170.7. mg/kg), zinc (5.1-261.3. mg/kg) and lead (2.6-385.45. mg/kg). Gold is significantly correlated with elements such as Sb, Cd, Pb, Ag, As, Cu and Mo. Relatively high anomaly contrasts between Au, As, Ag and Sb and their coinciding anomalies along an E-W trending fault at the eastern part of the field might indicate that As, Ag and Sb could be used as a pathfinder element for exploration of gold deposits. Factor analysis was applied to elements in soil samples and then distribution diagrams were prepared using the factor scores obtained. In a distribution diagram for mineralization-associated factor score, two anomaly fields along the E-W trending fracture line and one anomaly field at the eastern part were distinguished. The largest anomaly in an ellipsoidal shape with long axis of 350. m was obtained from the southeast part of the area. Anomaly patterns show that factor scores might yield suitable and net results for the exploration. NE-SW trending fracture system is not related to mineralization and is younger than E-W trending fracture line. However, the E-W trending fault system controls the mineralization; therefore, the eastern extent of this fault zone needs to be investigated.
AtıfScopus19WoS16OpenAlex20
İncele - Derleme MakaleYalnız künye2012Scopus SJRQ1Present situation and potential role of renewable energy in Turkey
Çapik, Mehmet; Yilmaz, Ali Osman; Çavuşoĝlu, Ibrahim
Turkey has a rich potential of hydropower, wind and geothermal energy resources. The distribution of these renewable energy sources in operation are hydropower, wind and geothermal 14.802 MW 1002MW and 94 MW, respectively. Turkey possesses a huge hydroelectric resource which is one of the Turkey's major energy assets. Most of the important uses of water in power plants have been developed in the electricity generation. Turkey has a total gross hydropower potential of 433 TWh/yr, which is equal to 13.8% of the total hydropower potential of European. Technically useable and economic potential are 216 TWh/yr and 140 TWh/yr, respectively. The total share of all energy for electricity power generation in 2010 are coal, natural gas, fuel oil and renewable energy, 104,040 GWh, 125,549 GWh, 18,215 GWh, and 86,120 GWh respectively. Among the renewable energy resources in Turkey, biomass and solar energy are also important because their share in total energy consumptions have increased. On the other hand, Turkey has not utilized nuclear energy yet. The current government plans to have a nuclear power plant with a capacity of 1800MW at the Black Sea Port of Sinop. The main purpose of the energy policies is to answer the energy needs of increasing population and growing economy at minimum costs while making energy supply planning. Turkey's specific national energy strategy document and energy policy objectives are outlined in the institutional strategic plans. These strategic plans are energy supply security, regional and global influence in the area of energy and environment protection. The aim of energy policy including renewable are to develop existing energy sources and to avoid dependence on energy imports and to encourage private sector investment and to improve the reliability of electricity supply. The main aim this study will investigate at the present potential of energy resources and future contributions to the national energy consumption in Turkey. As result present energy situation, the renewable energy potential, and the energy politics of Turkey are investigated.
AtıfScopus64WoS58OpenAlex79İncele - MakaleYalnız künye2011Scopus SJRQ1Assessment of natural radioactivity and mass attenuation coefficients of brick and roofing tile used in Turkey
Damla, N.; Cevik, U.; Kobya, A. I.; Celik, A.; Celik, N.; Yildirim, I.
In this study the distribution of natural radionuclides ((226)Ra, (232)Th, (40)K) in brick and roofing tile samples commonly used as building materials in Turkey was measured by using gamma spectrometry. The activity concentrations, radium equivalent activities (Ra(eq)), representative level index, indoor absorbed dose rate in air values and annual effective dose due to the intake of the above-mentioned radionuclides in the brick and roofing tile samples were estimated to assess the radiation hazard for people living in dwellings made of the materials studied. The measured average activity concentrations of (226)Ra, (232)Th and (40)K were 34 +/- 14, 34 +/- 13 and 462 +/- 175 Bq.kg(-1), respectively, for brick samples. For roofing tile, the average activity concentrations of (226)Ra, (232)Th and (40)K were measured to be 34 +/- 14, 33 +/- 12 and 429 +/- 161 Bq.kg(-1), respectively. The concentrations for these natural radionuclides were compared with the reported data of other countries. The Ra(eq) values of all samples were lower than the limit of 370 Bq.kg(-1), equivalent to a gamma dose of 1.5 mSv.a(-1) recommended by OECD. This study shows that the measured brick and roofing tile samples do not pose any significant source of radiation hazard and are safe to be used as building materials. Moreover, the experimental mass attenuation coefficients (mu/rho) of brick and roofing tile samples were determined in the energy range 80-1332 keV using the gamma ray transmission method. The experimental mass attenuation coefficients were compared with theoretical values obtained using XCOM. It was found that the computed values and the experimental results of this work are in good agreement with those reported in the literature. The chemical compositions and structural analysis (XRD) of the brick and roofing tile samples are also presented. (C) 2011 Elsevier Ltd. All rights reserved.
AtıfWoS35OpenAlex40İncele - MakaleAçık Erişim2011Scopus SJRQ3Bay laurel (Laurus nobilis L.) in Japanese quails feeding 1. Performance and egg quality parameters
Karaalp, Musa; Elmasta, Mahfuz; Genc, Nusret; Sezer, Metin; Yavuz, Musa; Ozkan, Mehmet
The aim of this study was to evaluate the effect of supplemented bay laurel (Laurus nobilis L.) leaves to a conventional diet of laying Japanese quail on the performance and some egg quality. A total number of 60 and 54 days old laying type quails were distributed into individual cages for three different treatments. The control diet did not containLaurus nobilis (LN) leaves (LNG) and the other diets were supplemented with 2 g (LN2) and 4 g (LN4) leaves kg-1, respectively. The trial lasted for a total of 10 weeks. Supplemented leaves of LN (2 or 4 g kg-1 feed) had no effect on any performance parameters, external and internal egg quality traits of quails. The diets have not changed the amount of egg yolk total cholesterol at 121 days old. However, egg yolk triglyceride concentration of quails fed LN4 diet was lower (p<0.01) than quails fed with the other diets at 121 days old. Besides, the amount of total cholesterol and triglyceride of egg yolk increased (p<O.01) in all of the groups with age. In egg yolk in the group receiving diet LN4, the level of palmitic acid was lower (p<0.05) and oleic acid was higher (p<0.05) than those of the other 2 groups at 118 days. Besides at that age, the level of pahnitic acid was lower and oleic acid was >55, 76 and 97 days. There was no change in the other fatty acids. The changes in total saturated and total monounsaturated fatty acids were parallel with palmitic acid and oleic acid, respectively. Total polyunsaturated fatty acid content in the present study did not change with diet and age. The results of this study demonstrated that supplemented a conventional diet with LN could change some biochemical parameters of quail egg yolk.
AtıfScopus14WoS9OpenAlex15İncele - MakaleYalnız künye2011Scopus SJRQ4New data on the harvestmen (Arachnida, Opiliones) fauna of Turkey
Kurt, Kemal; Snegovaya, Nataly Yu.; Demir, Hakan; Seyyar, Osman
A new collection of 8 species of harvestmen are reported from Turkey. Two of them: Zachaeus redikorzevi (Starega et Chevrizov, 1978) and Opilio coxipunctus (Sørensen, 1912), collected from the southern part of the country, represent new records for Turkish harvestmen fauna. These species are illustrated and their data regarding collecting sites and distribution all over the world are given.
AtıfScopus6WoS7İncele - MakaleYalnız künye2011Scopus SJRQ2A new Early Jurassic brachiopod fauna from the Eastern Pontides (Turkey)
Vörös, Attila; Kandemir, Raif
A newly collected Early Jurassic brachiopod fauna from the Kocamantaşi section (Gümüşhane region, Eastern Pontides, Turkey) yielded 160 specimens and 13 species (4 rhynchonellids, 3 spirifennids, 6 terebratulids). Apart from some long-ranging forms, five species prove the Late Pliensbachian age of the fauna. The paleoenvironmental setting of the Kocamantaşi fauna shows analogies to the Alpine Hierlatz limestones. On the basis of common lithological characters, bedding features and sedimentary associations, this lithofacies is interpreted as a complex of submarine, biodetrital talus associated with fault-related submarine rocky slopes. The numerical comparison of the Kocamantaşi brachiopod fauna to Pliensbachian brachiopod faunas of Europe revealed that the faunal similarity was the highest to Kotel (Balkans) and the Crimea. Very strong affinity was recorded to further NW-European faunas, whereas very low, or no similarity was recognized to the Mediterranean faunas. This paleobiogeographical result supports the hypothesis that in the Late Pliensbachian the Eastern Pontide segment of the Cimmerian microcontinent was far from the Gondwana and close to the Eurasian margin of the Tethys.
AtıfScopus18WoS17OpenAlex14İncele - MakaleYalnız künye2011Scopus SJRQ1Crystal fractionation of adakitic magmas in the crust-mantle transition zone: Petrology, geochemistry and U-Pb zircon chronology of the Seme adakites, eastern Pontides, NE Turkey
Eyuboglu, Yener; Santosh, M.; Chung, Sun-Lin
Plutonic and porphyritic intrusions of adakitic rocks are widely distributed in the southern part of the eastern Pontides orogenic belt in Turkey. Ranging in age from late Paleocene to early Eocene, these intrusions provide critical information to evaluate the early Cenozoic geodynamic evolution of the eastern Mediterranean region. Here we report the results from our field, petrologic, geochemical and zircon U-Pb geochronological studies on adakitic intrusions in the Seme area from the southern part of eastern Pontides belt. The Seme granitoid, Daldibi dacite and Aslanca dacite porphyry from this region carry abundant plagioclcase, amphibole and biotite phenocrysts and have geochemical affinities typical of adakites including high SiO2 (58.48-75.6wt.%), Al2O3 (15.78-18.28wt.%), Na2O (3.94-5.08wt.%), Sr (506-1413ppm), and La (12.6-52.9ppm), moderate K2O (1.77-2.76wt.%), and low Y (4.7-14.2ppm) and Yb (0.28-1.29ppm). The early Eocene intrusions in the Seme area have compositional similarities with high-slica adakites, and their geochemical features suggest the involvement of slab-derived melts. The zircons separated from these rocks show euhedral crystal shapes with oscillatory cores typical of crystallization from magmas, as also confirmed by their high Th/U ratios (0.78 to 1.15). U-Pb analyses of zircons from the quartz diorite yielded a weighted mean 206Pb/238U age of 53.16±0.45Ma. Zircon grains from the Aslanca dacite porphyry occurring as a late phase within the Seme body show U-Pb isotopic ages of 53 and 52Ma concordant with U-Pb ages of zircons from quartz diorite. Based on major, trace and rare earth element data, we present a model suggesting crystal fractionation and/or differentation processes of subduction-related adakitic magmas stored in the crust-mantle transition zone, and their transfer into shallow depths of the overriding continental lithosphere.
AtıfScopus104WoS99OpenAlex100İncele - MakaleAçık Erişim2011Scopus SJRQ3The first record of the genus Odiellus (opiliones, phalangiidae) in Turkey with some SEM studies on its morphology
Kurt, K.; Erman, O. Köksal
The harvestmen species Odiellus lendli (Soerensen, 1894), with its genus Odiellus Roewer, 1923, was found in Anatolia. It represents a new record of Turkish harvestmen fauna. The characteristic features of this species are described and illustrated. Scanning electron microscopy (SEM) studies on the dorsal integument, ventral habitus, chelicerae, pedipalpus, trident, the ocularium and legs of female specimens are also presented. Localities of the collecting sites are photographed and plotted on a map.
AtıfScopus4WoS4OpenAlex2İncele - MakaleYalnız künye2011Scopus SJRQ1Modeling and forecasting of Turkey's energy consumption using socio-economic and demographic variables
Kankal, Murat; Akpinar, Adem; Kömürcü, Murat Ihsan; Özşahin, Talat Şükrü
This study deals with the modeling of the energy consumption in Turkey in order to forecast future projections based on socio-economic and demographic variables (gross domestic product-GDP, population, import and export amounts, and employment) using artificial neural network (ANN) and regression analyses. For this purpose, four diverse models including different indicators were used in the analyses. As the result of the analyses, this research proposes Model 2 as a suitable ANN model (having four independent variables being GDP, population, the amount of import and export) to efficiently estimate the energy consumption for Turkey. The proposed model predicted the energy consumption better than the regression models and the other three ANN models. Thus, the future energy consumption of Turkey is calculated by means of this model under different scenarios. The predicted forecast results by ANN were compared with the official forecasts. Finally, it was concluded that all the scenarios that were analyzed gave lower estimates of the energy consumption than the MENR projections and these scenarios also showed that the future energy consumption of Turkey would vary between 117.0 and 175.4. Mtoe in 2014.
AtıfScopus233WoS199OpenAlex282İncele - MakaleAçık Erişim2011Scopus SJRQ2Arc magmatism as a window to plate kinematics and subduction polarity: Example from the eastern Pontides belt, NE Turkey
Eyuboglu, Yener; Santosh, M.; Bektas, Osman; Ayhan, Seda
The Eastern Pontides orogenic belt in the Black Sea region of Turkey offers a critical window to plate kinematics and subduction polarity during the closure of the Paleotethys. Here we provide a brief synthesis on recent information from this belt. We infer a southward subduction for the origin of the Eastern Pontides orogenic belt and its associated late Mesozoic-Cenozoic magmatism based on clear spatial and temporal variations in Late Cretaceous and Cenozoic arc magmatism, together with the existence of a prominent south-dipping reverse fault system along the entire southern coast of the Black Sea. Our model is at variance with some recent proposals favoring a northward subduction polarity, and illustrates the importance of arc magmatism in evaluating the geodynamic milieu associated with convergent margin processes.
AtıfScopus47OpenAlex50İncele - MakaleYalnız künye2010The Alteration Mineralogy and Mass Change of the Zigana (Gumushane) Volcanics of NE Turkey
Sipahi, Ferkan; Sadiklar, M. Burhan
The Late Cretaceous volcanic rocks around Zigana Mountain (Gumushane) in the eastern Black Sea metallogenic province in NE Turkey show intensive hydrothermal alteration but less weathering alteration. The basement of the study area is formed by Late Cretaceous basalt, andesite and their pyroclastics. These rocks are overlain by dacitic rocks of the same age, namely Dacite-I and Dacite-II. These volcanic rocks are bimodal in character and have developed in a volcanic arc environment. The volcanic rocks in the study area have been altered to the sericite/illite-chlorite facieses, and contain sericite/illite, chlorite, quartz, carbonate minerals (ankerite and calcite), iron-oxide, and rare kaolinite, smectite and epidote as the products of alteration. Sericitization/illitization is the most common type of hydrothermal alteration associated with these volcanics, and chloritization is the most common alteration type after illitization; pyritisation is seen in all volcanics, and is the most common in dacites. In some fields limonitisation is occasionally present. Epidotization is rare, and especially seen in basalt and andesite. Isocon analysis was undertaken to estimate the mass gains and losses of the Zigana Volcanics as a result of hydrothermal alteration. In general terms, the results shows that, basalt and andesite have 2-61% mass gain, Dacite-I 71% mass gain and 42 % mass loss, and Dacite-II 44% mass gain and 32% mass loss. Namely, both mass gain and mass loss occurred in the volcanics during the hydrothermal alteration of the parent materials. From less altered rock to highly altered rock there was an increase in illite-chlorite-kaolinite whereas there was a decrease in carbonate minerals. In the volcanics, fluids which cause sericitization and chloritization did not increase metals like Cu, Pb and Zn and, in fact, it can be said that these fluids are poor in point of these metals. This also shows that the metals developed under different hydrothermal conditions.
AtıfWoS2İncele - MakaleYalnız künye2010Scopus SJRQ1Late Cretaceous high-K volcanism in the eastern Pontide orogenic belt: Implications for the geodynamic evolution of NE Turkey
Eyüboǧlu, Yener
High-K volcanics were produced in two different Late Cretaceous cycles during the infilling of back-arc basins of the eastern Pontides. The first cycle, represented by shoshonitic trachyandesites and associated pyroclastics, containing high K2O (2.74-4.81 wt-%) and NaK2O (3.60-5.51 wt-%), overlies a mid-Cretaceous ophiolitic-olistostromal melange formed during the rifting stage of a back-arc basin (Neotethys). 40Ar39Ar dating of biotite from trachyandesite at the base of the first cyle indicates that shoshonitic volcanism in the far south of the eastern Pontides started in the early Campanian. Volcanic rocks of this cycle are overlain by upper Campanian-Maastrichtian rudist-bearing reefal limestones. The second cycle of high-K volcanism is represented by analcime-bearing volcanic rocks erupted in a Neotethyan lagoonal environment. These volcanic rocks, intercalated with continental detritus, are characterized by high a2O (3.22-7.16 wt-%), now concentrated in secondary analcime crystals. Their K2O contents also range between 0.83 and 6.05 (wt-%). All of these units are disconformably overlain by Eocene turbidites with a basal conglomerate. Volcanic rocks belonging to both cycles show various enrichment degrees in LILE, HFSE, LREE, and HREE with respect to primitive mantle and chondrite [(La/Lu) cn=11.10-25.89]. Negative Nb, Ta, Zr, Hf, and Ti anomalies are typical of these subduction-related arc magmas. Geochemical similarities between the two volcanic cycles suggest that trachyandesites and analcime-bearing volcanics were derived from similar enriched mantle sources, and that they formed in the same geotectonic setting of a back-arc basin environment of the eastern Pontide magmatic arc during the Late Cretaceous. In addition, Nd-Sr and Pb isotope ratios of the investigated volcanic units indicate that their mantle melt sources were similar. The new geological, geochemical and isotopic data suggest that southward subduction of the Palaeotethyan oceanic crust can be separated into two main stages for the late Mesozoic Pontide orogenic belt. Early southward subduction ended by slab break-off during the mid-Cretaceous, resulting in upwelling and injection of asthenospheric mantle that caused the opening of the eastern Pontide back-arc basin (Neotethys). Resumption of southward subduction began with intense TH-CA bimodal volcanism in the northern front of the arc during the Turonian-Coniacian. The intensity of this Late Cretaceous magmatism in the north decreased towards the south, and a transition to monogenic calcalkaline-alkaline (CA-A) Campanian andesitic volcanism developed in the southern zone. Yet farther south, andesitic igneous activity graded into the Campanian-Maastrichtian shoshonitic and ultrapotassic volcanism in the Bayburt-Maden, Tokat, Amasya, and Gümüshaciköy areas. This zoning of the Late Cretaceous arc magmatism (TH-CA, CA-A and shoshonitic-ultrapotassic, from north to south) also supports the concept of southward subduction during late Mesozoic evolution of the eastern Mediterranean region.
AtıfScopus120WoS110OpenAlex117İncele - MakaleYalnız künye2010Scopus SJRQ3Assessment of medical home care needs in Turkish population
Sahinoz, Saime; Sahinoz, Turgut; Eker, Hasan Huseyin; Unlu, Suleyman Ersin
Objective: To determine the home healthcare needs of the elderly so as to develop proper home Healthcare Services. Methodology: This descriptive study was carried out in a county of Kocaeli province-Turkey. Data was collected through a specially designed questionnaire through face to face interview technique. The data were analyzed by the computer using the SPSS package program. Chi-square test was used for the statistical analysis. Results: This study showed that 14.6% of the population had at least one diagnosed disease. Among them, 1.8% was disabled, 4.1% was elderly and 1.1% of the households were in need of home care services. Conclusions: Home care needs were found to be low in this study. Its main cause was that elderly population was not aware of the availability of such a service in the country.
- MakaleYalnız künye2010Scopus SJRQ1Sources and petrogenesis of Jurassic granitoids in the Yusufeli area, Northeastern Turkey: Implications for pre- and post-collisional lithospheric thinning of the eastern Pontides
Dokuz, Abdurrahman; Karsli, Orhan; Chen, Bin; Uysal, Ibrahim
Small granitoids emplaced into the early Jurassic volcani-clastic succession in the Yusufeli area, northeastern Turkey, can be temporally and geochemically classified into two groups: early Jurassic low-K and late Jurassic high-K. 40Ar-39Ar hornblende analyses yielded 188.0 ± 4.3 Ma for the Dutlupi{dotless}nar intrusion, dating the subduction related rifting in the region. It comprises metaluminous to weakly peraluminous (ASI = 0.94-1.11) granodiorite and, to a lesser extent, tonalite whose K2O-poor (< 2.04 wt.%) nature and weak negative Eu anomalies (Eu/Eu* = 0.9-0.7) preclude derivation by fractional crystallization from a K-rich melt. Sr, Nd and Pb isotopic data reveal derivation by partial melting from an already cooled tholeiitic basic rocks which had mantle-like isotope signature. The Sumbated intrusion formed in the late Jurassic (153.0 ± 3.4 Ma) and consists chiefly of metaluminous (ASI = 0.84-0.99) quartz monzodiorite. Medium to high-K2O, relatively high MgO and Sr contents, flat HREE patterns without prominent Eu anomalies, slightly positive εNd(t) values (+ 1.5 to + 2.5) and low ISr ratios (0.7046-0.7056) are consistent with an origin by dehydration melting of a juvenile source, above the garnet stability field, dominated by likely K-amphibole bearing calc-alkaline mafic rocks. Geochemical data show that fractional crystallization from a Sumbated-like quartz monzodioritic magma is the fundamental process responsible for the evolved compositional range of the Keçikaya intrusion. The geochemical and geochronological data presented here indicate that the late Jurassic magmatism occurred in a post-collisional setting. Slab-breakoff, which was followed by shortly after collision, seems to be the most plausible mechanism for the generation of medium to high-K calc-alkaline rocks of the Sumbated and the Keçikaya intrusions, indicating a switch in the geodynamic setting, e.g., from pre-collision to post-collision in the middle Jurassic in the eastern Pontides.
AtıfScopus123OpenAlex122İncele - MakaleYalnız künye2009Scopus SJRQ2Determination of tectonic and crustal structure of the eastern pontide orogenic belt (NE Turkey) using gravity and magnetic data
Maden, Nafiz; Gelisli, Kenan; Eyuboglu, Yener; Bektas, Osman
The Eastern Pontide Orogenic Belt is one of the most complex geodynamic settings within the Alpine belt. Subduction polarity, which is responsible for the formation of the Eastern Pontide Magmatic Arc, is still under debate because of limited geological, geophysical and geochemical data. This orogenic belt is mainly divided into three subzones depending on lithological characteristics and facies changes as in Northern, Southern and Axial Zones from North to South. These zones are separated from each other by near-vertical faults that display the block-faulting tectonic style of this belt. In this study, the tectonic and crustal structure of the Eastern Pontides, which as yet have not been prospected by using geophysical data, has been investigated with potential field data. The horizontal gradient map obtained from gravity data shows a number of steep and gentle lineaments. It seems that these lineaments E-W, NE and NW-trending correspond to major structural zones of continental crust. Additionally, The Moho depth and Curie point depth variation maps of the Eastern Pontide Orogenic Belt have been computed with the power spectral method of the radial wavenumber carried out by using the fast Fourier transform method. As a result of this method, we estimated that the depths of the Moho and Curie point varied between 29.0 ± 1.2-47.2 ± 1.9 km and 14.3 ± 0.7-27.9 ± 1.4 km, respectively. Our findings indicate that the Moho depth generally increases from north to south in the region. However, the Curie point depth level within the crust has an undulating surface, not a horizontal one.
AtıfScopus41WoS40OpenAlex39İncele - MakaleYalnız künye2008The rift-related Late Cretaceous drowning of the Gümüşhane carbonate platform (NE Turkey)
Yilmaz, Cemil; Carannante, Gabriele; Kandemir, Raif
In the Gümüşhane region (NE Turkey), carbonate platform and basin deposits, crop out with excellent exposures. In this area, two localities (Mescitli-İkisu region, 10 km west of the Gümüş hane and Kale-Kilop region, 20 km southeast of the Gümüşhane), in which the related successions are particularly well exposed, have been studied in detail. The outcropping shallow water limestones of the Berdiga Formation (Eastern Pontides Carbonate Platform) were deposited during Late Jurassic-Cenomanian p.p. times in peritidal environments. The overlying Kermutdere Formation consists of monogenic breccias, calciturbidites, red pelagic limestone and siliciclastic turbidites, which were deposited in slope and basin environments. In the Gümüşhane region, the above Formations record the evolution from platform to basin settings in relation to an extensional regime set up in the Cenomanian. The tectonics-related drowning of the Eastern Pontides carbonate platform resulted in graben-semi graben basins in which deep marine sediments were deposited during Late Cretaceous times, having a wedge geometry.
AtıfScopus14İncele - MakaleYalnız künye2008Scopus SJRQ1New chemical weathering indices for estimating the mechanical properties of rocks: A case study from the Kürtün Granodiorite, NE Turkey
Ceryan, Şener
The chemical weathering of rock proceeds by water-rock interaction. During weathering geochemically mobile elements, alkali and alkali-earth elements are easily leached from rocks, leaving the residual elements to combine with components from the atmosphere to form new minerals. No single, weathering index given in the literature fits the model of the process involved in chemical weathering outlined above. This study deals with the derivation of three new chemical weathering indices oy taking both chemical processes such as leaching and new mineral formation into account. The new indices are chemical leaching index (CLI), chemical weathering product index (CWPI) and total chemical weathering index (TCWI). These indices are applied to selected weathering profiles in the Kürtün granodiorite, NE Turkey, in order to estimate the effects of chemical weathering on the physico-mechanical properties of rock materials. The relative variation of the mechanical properties and TCWI display a statistically significant correlation. Besides, it is shown that TCWI and weatherability index, originally defined by Hodder (1984) can be used together to evaluate the effect of chemical weathering on the mechanical behaviour of rocks.
AtıfScopus48İncele - MakaleYalnız künye2007Scopus SJRQ1The magnetic susceptibility of granitic rocks as a proxy for geochemical composition: Example from the Saruhan granitoids, NE Turkey
Aydin, Ali; Ferré, Eric C.; Aslan, Zafer
The magnetic susceptibility of rocks is determined by their bulk chemistry and magnetic mineralogy. In this case study of the Saruhan pluton in Turkey, a detailed survey based on 925 field measurements and 37 whole rock analyses, reveals a strong correlation between magnetic susceptibility and FeOt (R2 = 0.8). Petrographic observations and calculations based on whole-rock major element analyses indicate the presence of magnetite grains. Further calculations show that magnetite accounts for 88% of the magnetic susceptibility. The spatial correlation between FeOtotal and the magnetic susceptibility is particularly spectacular which suggests that Km is a proxy for geochemical differentiation. The zoning pattern of magnetic susceptibility across the pluton is concentric and reverse, with the highest values of magnetic susceptibility in the center. This type of zoning is consistent with a previously proposed petrogenetic model. The comparison of the Saruhan granites with a classic example of paramagnetic granites reveals two contrasted FeOt-Km trends. This suggests that these variations can be a useful tool to distinguish between leucocratic paramagnetic and leucocratic ferrimagnetic granites.
AtıfScopus61WoS55OpenAlex73İncele - MakaleYalnız künye2006Scopus SJRQ1Mineralogy, petrography and whole-rock geochemistry of the Tertiary granitic intrusions in the Eastern Pontides, Turkey
Arslan, M.; Aslan, Z.
Granitic intrusions in Eocene and post-Eocene volcanic rocks outcrop in the Northern and Southern Zones of the Eastern Pontides, NE Turkey. Intrusions in the Northern Zone extend NW-SE whereas those in the Southern Zone are nearly E-W orientated. The contacts of the intrusions with the volcanic rocks are sharp, epidotized and include volcanic xenoliths. The margins of Southern Zone intrusions often contain abundant angular mafic microgranular enclaves of diorite to quartz diorite composition. The rocks also show evidence of mingling and mixing between coeval mafic and felsic magmas. Field observations suggest a stopping type of ascent and emplacement style for the intrusions. Petrographically, intrusions show variations in both colour and mineralogy with fine to medium granular, monzonitic, poikilitic, rapakivi, anti-rapakivi and graphic textures. Based on modal mineralogy, the Northern rocks are monzonite, quartz monzonite, monzodiorite and quartz monzodiorite whereas the Southern samples are monzogranite and granodiorite. The rocks are generally calc-alkaline to mildly alkaline transitional and metaluminous, and show a CAFEMIC trend. The Northern Zone intrusions form a post-collisional, A-type, alkaline monzonitic association and Southern Zone intrusions form a post-collisional, I-type, granodioritic calc-alkaline-transitional association. Whole-rock compositional data indicate that differentiation occurred via fractional crystallisation with or without magma mixing. Incompatible and rare earth element patterns indicate that both the Northern and the Southern Zone intrusions were derived from melting of a mantle region enriched by subduction-related fluids but evolved differently during ascent and emplacement. U-Pb zircon dating in the Southern Zone yields an intrusion age of 44.4±0.3 Ma. Regional geodynamics indicates post-collisional extensional tectonics in the region. Crustal involvement and the level of emplacement may have been important for magmatic evolution, especially for the Southern Zone intrusions, after the cessation of subduction and subsequent crustal thickening.
AtıfScopus171WoS154OpenAlex160İncele - MakaleAçık Erişim2006Scopus SJRQ1A mantle- and a lower crust-derived bimodal suite in the Yusufeli (Artvin) area, NE Turkey: Trace element and REE evidence for subduction-related rift origin of Early Jurassic Demirkent intrusive complex
Dokuz, Abdurrahman; Tanyolu, Erkan; Genç, Salim
The Yusufeli area, in the Eastern Black Sea Region of Turkey, contains a crystalline complex that intruded into the Carboniferous metamorphic basement and is composed of two intrusive bodies: A gabbro-diorite and a tonalite-trondhjemite. The mafic body (45-57 wt% SiO2) displays a broad lithological spectrum ranging from plagioclase-cumulate to quartz diorite. Primitive varieties of the body have Mg-number, MgO and Cr contents that are close to those expected for partial melts from mantle peridotite. Data are consistent with the magma generation in an underlying mantle wedge that was depleted in Zr, Nb and Ti, and enriched in large ion lithophile elements (K, Rb, Ba, Th). However, high Al2O3, CaO and generally low Ni (<65 ppm) contents are not in agreement with the unfractionated mantle-derived primitive magmas and require some Al2O3- and CaO-poor mafic phases, in particular, olivine and orthopyroxene. Absence of orthopyroxene in crystallization sequence, uralitization, and a common appearance of clinopyroxene surrounded by hornblende imply an anhydrous phase fractionated from highly hydrous (5-6%) parent. Geochemical modelling suggests derivation by 15-20% melting of a depleted-lherzolitic mantle. The tonalite-trondhjemite body (58-76 wt% SiO2) ranges in composition from quartz diorite to granodiorite with a low-K calc-alkaline trend. Although LILE- and LREE- enriched characteristics of the primitive samples imply a metasomatic sub-arc mantle for their source region, low MgO, Ni and Cr concentrations rule out direct derivation from the mantle wedge. Also, lack of negative Eu anomalies suggests an unfractionated magma and precludes a differentiation from the diorites of mafic body, which show negative Eu anomalies. Their Na enrichments relative to Ca and K are similar to those of Archean tonalites, trondhjemites and granodiorites and Cenozoic adakites. However, they exhibit important geochemical differences from them, including low-Al (<15 wt%) contents, unfractionated HREE patterns and evolution towards the higher Y concentrations and lower Sr/Y ratios within the body. All these features are obtained in experimentally produced melts from mafic rocks at low pressures (≤5 kbar) and also widespread in the rocks of arc where old (Upper Cretaceous or older) oceanic crust is being subducted. Major and REE modelling supports formation of the quartz dioritic parent to the felsic intrusive rocks by 70% partial melting of a primitive gabbroic sample (G694). Therefore, once taking into account the extensional conditions prevailing in the Pontian arc crust in Early Jurassic time, former basic products (gabbros) seem to be the most appropriate source for the tonalite-trondhjemite body. Magmatic emplacement of stratigraphically similar lithologies in the Pulur Massif, just southwest of the Yusufeli, was dated to be 184 Ma by the 40Ar/ 39Ar method on amphibole, and is compatible with the initiation of Early Jurassic rifting in the region.
AtıfScopus76OpenAlex73İncele