Adil Doğan AZEZLİ, Serdar MAYDA, M. Cihat ALÇİÇEK
Adil Doğan AZEZLİ, Serdar MAYDA, M. Cihat ALÇİÇEK
The large fossil vertebrates obtained from the alluvial flood-plain deposits of the Kolankaya formationare determined as Skoufotragus laticeps (Andree, 1926) and Hipparion brachypus (Hensel, 1862),as representative elements of palaeomammal faunas spanning from the eastern Mediterranean toIranian domains during the late Miocene (early-middle Turolian, MN11-12). These first Turolianrecords from the basin fill succession bear importance on reconstruction for the palaeobiogeographicdiversity of relevant taxons as well as admit of interbasinal stratigraphic correlation for the WesternAnatolian terrestrial Neogene basins.
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Coşkun GÜNEŞ, Emrah PEKKAN, Muammer TÜN
Coşkun GÜNEŞ, Emrah PEKKAN, Muammer TÜN
Technological developments on Geographical Information Systems (GIS) make possible to useits applications on all departments of earth sciences. GIS based drill-hole data, lithological andstructural maps are used integrated with field geolgy investigations in this study. The area where isbordered Batıkent-Yukarı Söğütönü districts on northwest and Vadişehir-Ihlamurkent districts onsoutheast is defined as study area. 44 water wells drilled by State Hydraulic Works (DSİ) are locatedin various points of Eskişehir region were transformed to GIS base. Geological cross-sections whichwere designed by drill-hole lithology are point out a disconformity zones between Paleogene andNeogene according to principle of lateral continuity. Neotechtonic researches on study area showthah right lateral strike slip shear zone dominates the region structurally. Searching these structuraltraces on the field and representing new field evidances by using GIS on the regions where there isno consensus stratigraphicly are the main purposes of the study. Geological map of the region wherelies between Çankaya and Karapınar districts without consensus stratigrapichly was made by fieldobservations on Miocene units. The other surface evidances include dilation fractures, strike-slipfaults are support the idea which is suggested for Eskişehir region as right lateral strike-slip shearzone.
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Ayhan ILGAR, Tolga ESİRTGEN, Banu TÜRKMEN BOZKURT, Serap DEMİRKAYA
Ayhan ILGAR, Tolga ESİRTGEN, Banu TÜRKMEN BOZKURT, Serap DEMİRKAYA
The lacustrine units have been deposited in the Ermenek, Bucakkışla, Korucuk and Çamlıyayla basinsin the Central Taurides since early Oligocene. In this study, structural features and stratigraphicalproperties of Oligocene basins have been described in detail and the lacustrine units have beendated. Regional geological interpretations have been made by using tectono-stratigraphic and agedata of the basins. Lacustrine Oligocene sedimentation in these basins, which were opened onthe tectonic units of Taurides due to normal faults, constitute the first records of the sedimentationoccurring under the extensional tectonic regime after the orogeny of the Central Taurides. All the preOligocene units that had been emplaced in the region due to a north-south compressional movementin the Central Taurides, continued to be compressed until the end of Eocene, and completed theirorogenic development as napped structures. The bedrock units, reaching the maximum elevation,have been subjected to “orogenic collapse” due to the strain or gravity forces as a result of aninterruption or termination of the compression which lasted until the end of Eocene. Thus, “orogeniccollapse” basins have started to be formed in the Central Taurides since Oligocene. The orogenyand the compressional tectonic regime forming the Taurides lasted until late Miocene in the EasternTaurides. On the other hand, extensional basin formation since early Oligocene on the Taurus units,which had been emplaced in the region due to nappe tectonics, indicates that a new tectonic periodhas started in the Central Taurides.
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Anıl ARDAHANLIOĞLU, Gürol SEYİTOĞLU, Korhan ESAT
Anıl ARDAHANLIOĞLU, Gürol SEYİTOĞLU, Korhan ESAT
The Beypazarı Blind Thrust Zone, which is surrounded by the North Anatolian, the Eskişehir, andthe Kırıkkale-Erbaa fault zones, is a recently defined neotectonic structure developed in the NWcentral Anatolia together with the Eldivan-Elmadağ and the Abdüsselam Pinched Crustal Wedges.In this study, the internal structure of the Beypazarı Blind Thrust Zone has been examined in detailaround Çayırhan region. It has been defined that it consists of the Karaköy, Sekli, Nalçabayırı,Uzunbayır blind thrusts, Davutoğlan Back Thrust, and Beypazarı Blind Thrust I-II from northto south, respectively with help of the fault-propagation folds in the study area. The existence ofeconomically important and operational resources such as lignite and trona in the Neogene sequenceaffected by these faults in the region and earthquake generating potential of the faults determined inprevious studies increase the importance of this study.
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Doğan KALAFAT, Yavuz GÜNEŞ, Mehmet Akif KARA, Kıvanç KEKOVALI
Doğan KALAFAT, Yavuz GÜNEŞ, Mehmet Akif KARA, Kıvanç KEKOVALI
Western Anatolia is one of the most seismically active regions in Turkey. The high seismic activityis a result of a complex tectonic deformation dominated by the N-S extensional tectonic regime inWestern Anatolia. This tectonic deformation is also a result of the relative movement of the AfricanArabian plates towards the north, which causes the Anatolian plate to shift 2.5 cm per year towardsW-SW. One of the largest fault zones in the Western Anatolia, Sultandağı Fault Zone (SFZ) hasa northwest-southeast trend. SFZ, approximately 120 km long, is an important tectonic structure,which produced three major earthquakes (Mw> 6.0) between the years of 2000 -2002. Therefore, themost significant goals of this study were to monitor the micro-earthquakes along SFZ, to enrich thecurrent seismic network and to increase the earthquake detection threshold in the region (Mc <2.5).Within the scope of the study, 3 digital broadband earthquake stations were installed in the region.The analysis of the data obtained in the research indicated that the central and western parts of SFZare active and there is intense seismic activity especially in the vicinity of Sultandağı, Çay, Çobanlar,and Afyonkarahisar. Fault plane solutions revealed that the earthquakes in the region generally occurwith normal faulting with oblique components. Seismic stations installed within the scope of thestudy contributed positively to the increase of the sensitivity (Mc = 1.3) of the earthquake detectionthreshold (Mc) in the region and increased the detection capacity
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The geothermal energy is a renewable and relatively clean energy resource. The amount ofgeothermal energy stored just in the upper crust of the earth is large enough to meet the world’senergy needs for thousands of years. Unfortunately, only a small portion of this potential can beutilized today by the conventional methods. The rest corresponds to the hot, fluid-poor areas whichcannot be utilized by the current technology. The first concrete steps towards the utilization ofsuch high potential areas emerged in the late 1960s and early 1970s. These studies have graduallycontinued in the following years, and many new terms and conceptual designs have been proposedso far. Unfortunately, no comprehensive definition has been established on this subject yet. This maybring about some difficulties such as the failure to express the intended concept in the right manner,the inability to determine the legal boundaries for the regulations required by the countries to makeuse of these areas which pose high risks in the commercial point of view. In this paper, some of themajor terms and conceptual designs used for the projects targeting the power generation from fluidpoor hot areas are discussed. Furthermore, all of these terms have been gathered under the title of“Unconventional Geothermal Systems-UGS” and these designs are classified according to the typesof thermodynamic system for the first time in this study. In addition, some new suggestions that canbe used to define the definitional boundaries of these terms are put forward.
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The aim of this study was to delineate copper mineralization controllers in Nohkouhi volcanogenicmassive sulfide (VMS) deposit by using geostatistical and fractal simulation. In this study,concentration-volume (C-V) fractal model has been used to indicate various copper populationsrelated to different host rocks and copper minerals. Accordingly, uncertainty-volume (U-V) fractalmodel was applied to probability values achieved through sequential indicator simulation (SIS).Copper ores of Nohkouhi deposit including chalcopyrite and malachite were simulated in 30realizations. The U-V fractal model obtained by using a probability map was divided into fourprobability zones (high, moderate, low, and very low) for copper minerals. Furthermore, coppergrades were simulated for 10 times by sequential Gaussian simulation (SGS). Combination ofC–V and U-V fractal modeling resulted in a hybrid method which could be properly employedto determinate various mineralization zones based on the relationship between quantitative (e.g.copper grade) and qualitative (e.g. copper minerals) variables. Moreover, integrating the resultsof C–V and U-V fractal modeling with the most frequent occurrence of rock type modeling helpsidentify copper mineralization controllers in a VMS deposit.
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The Salda Lake basin which is in the southwestern Turkey is an important water body in view ofenvironmental values. We used stable isotopes (δD and δ18O), δ3H and 14C composition of the watersamples to understand recharge process effective in the groundwater and lake water. Water sampleswere collected in dry and wet periods and the stable isotope (δD and δ18O) and radiogenic isotope(14C) analysis were made in the basin. The δ18O contents of groundwater and lake water rangedfrom -9,94‰ to 1,18‰ in dry period and from -10,24‰ to 0,30‰, in wet period. δD contents ofgroundwater and lake water varied from -67,42‰ to 1,20‰ and from -64,51‰ to -2,80‰, in dryand period wet respectively. The stable isotope data of samples indicate a meteoric origin for allsamples. According to stable isotope data, groundwater samples seem to be recharged from higherelevations whereas the lake water is recharged from low elevations. The tritium (δ3H) content ofthe water samples ranges from 1.04 to 4.49 TU and from 1.91 to 4.18 TU in the dry period and wetperiod respectively. Long-term δ3H observations are required to determine whether these δ3H signalsare associated with young recharge or with the groundwater with long residence time. In addition,the 14C activities of the samples vary between 90 pmc and 110 pmc for Salda Lake waters and 530pmc and 5990 pmc for the groundwater.
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Gökçeada Island, which is situated west of Biga Peninsula, has widespread magmatism withvariable ages. Lower-Middle Eocene Dağiçitepe volcanics are the oldest volcanic unit in theisland and consist of lavas, tuff-tuffites. They are influenced by alteration and almost all minerals,except quartz, are transformed into other minerals. Lower Oligocene Gökçeada andesitic lava/domes exhibiting hypocrystalline porphyric texture, are the products of NE-SW trending domes/cryptodomes. The phenocrysts assemblages consist of plagioclase, hornblende, clinopyroxene ±biotite and quartz. Middle Miocene Eşelek volcanics, which occur as lavas and pyroclastic rocks,exhibit hypocrystalline porphyric and intersertal textures. They are composed of plagioclase,hornblende and clinopyroxene crystals. Rhyolitic Dağiçitepe volcanics and andesitic Gökçeadalava/domes have calc-alkaline, andesitic Eşelek volcanics have tholeiitic character. They havegeochemical features similar to subduction-related magmas. Lower-Middle Eocene Dağiçitepevolcanics are the products of syn-collisional magmas that have undergone processes of crustalcontamination due to thickened crust. Whereas, Lower Oligocene Gökçeada andesitic lava/domes arethe products of post-collisional magmas and were derived from metasomatized lithospheric mantle.Middle Miocene Eşelek volcanics were also derived from lithospheric mantle but, the mantle sourcegenerating Eşelek volcanics were relatively depleted over time. Geochemical data demonstrate thedecreasing role of subduction signature and crustal contamination during the genesis and evolutionof Gökçeada volcanics from Lower-Middle Eocene to Middle Miocene.
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The Nevruztepe iron-copper prospect is a skarn near Yeşilhisar (Kayseri). It has been overlookedas a potential producer of copper. The skarn was generated in Permian to Jurassic carbonate rocksby the Eocene Yahyalı granitic pluton. Lithologic units, including skarns, dip about 15 degreessouthward. Skarns are both prograde (garnet and diopside) and retrograde (epidote); both exoskarnand endoskarn exist. Most of the magnetite is in a quartz-sulfide stage in retrograde skarn that iscut by veins and lenses containing quartz-pyrite-chalcopyrite. Granite and mineralized skarn arerare at the surface. From 2013 to 2015, 31 drill holes (totaling 6.178,5 m) encountered skarn to adepth of 450 m. Mineralized zones vary from 1,2 to 54,7 m thick. Fe mean grade ranges from 12%to 49%; mean copper grades vary from 10 to 4650 ppm. The deposit contains 5.096.788 tonnes ofmineralized material. Microscopy on samples of drill core shows that the ore minerals are primarilymagnetite, hematite, and chalcopyrite. Some magnetite is altered to hematite. Experiments showthat with grinding to 100 microns the iron can be beneficiated to 66%. Waste from separation ofthe magnetite is 0.16 to 0.19% Cu; with flotation this was beneficiated to 19% Cu.
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