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    Evolution of Can-Etili (Canakkale-NW Turkey) lignite basin: Sedimentology, petrology, palynology and lignite characterization
    (Irtces, 2015) Bozcu, Mustafa; Akgun, Funda; Gurdal, Gulbin; Bozcu, Ayse; Yesilyurt, Sevinc Kapan; Karaca, Oznur; Akkiraz, M. Serkan
    This study examines the development and sedimentology of Can-Etili lignite basin in Biga Peninsula (NW Turkey) along with the palynologic and petrographic properties of the coals in this region. The Can-Etili lignite basin discordantly overlies Oligocene-aged Can volcanics. The basin consists of caldera type sedimentation developed by the combined effects of volcanism and tectonics. The volcanic rocks forming the basement of the basin consist of andesitic, dacitic and basaltic lava flows as well as agglomerates, tuff and silicified tuffs, and kaolin which is their alteration product. The basement volcanic rocks cooled from high potassium and calc-alkaline magma. The trace element geochemistry of different rocks within the volcanics reveals that they are from a volcanic arc. The Can Formation contains lignites and consists of 6 lithofacies representing alluvial, fluvial, marsh and lacustrine environments. These lithofacies are the lower volcanogenic conglomerate, the claystone, the lignite, the laminated organic claystone, the tuff intercalated sandstone-siltstone and the upper volcanogenic conglomerate. The lignite in the basin is limnic and is formed in a non-fluvial marsh and marsh-lake environment. An abundant percentage of vegetation (Engelhardia, Sapotaceae, Cyrillaceae) is compatible with temperate and subtropical climatic conditions in the basin during sedimentation of lignite. The coals of Can-Etili basin are humic with high sulfur content (6-6.5% average) mostly containing huminite compounds belonging to the class of lignite-low bituminous (C-A) coal. Their coalification rank is between 0.38% and 0.56% Ro. The coals are formed in limnic-limnotelmatic marsh zones based on their microlithotype components. The inorganic components of the coal mostly consist of pyrite and clay. The trace elements, As, Th, U and V, are higher than international coal standards. The coal quality is adversely affected by high sulfur content and sulfur driven trace element enrichments. The lignite reserve (possible-proved) of Can-Etili basin is greater than a hundred million tons, and the average coal seam thickness is 17 m. The lignite production in the basin is 3 mt/year and 1.8 million tons of this are used in the local thermal power plant. (C) 2015 International Research and Training Centre on Erosion and Sedimentation/the World Association for Sedimentation and Erosion Research. Published by Elsevier B.V. All rights reserved.
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    New evidence for the record of the Cenomanian-Turonian oceanic anoxic event (OAE2) in the Pamphylian basin (Akdogan Section, Antalya Nappes, SW Turkey): Comparison with surrounding basinal settings
    (Academic Press Ltd- Elsevier Science Ltd, 2011) Bozcu, Ayse; Baudin, Francois; Danelian, Taniel; Vrielynck, Bruno; Bozcu, Mustafa; Poisson, Andre
    The organic-rich black shales in the Akdogan section (Antalya Nappes, SW Turkey) are the first reported evidence of the global Cenomanian-Turonian Oceanic Anoxic Event (OAE2) in the Isparta Angle region. Their age and organic geochemical characteristics are similar to those of other OAE2 intervals in the Pamphylian basin and neighbouring basins of the Tethyan realm. A short description of the whole Akdogan sequence allows us to compare it with other similar sequences in the surrounding areas and to discuss the local versus global controlling factors on the record of OAE in the Pamphylian basin. (C) 2011 Elsevier Ltd. All rights reserved.
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    Oligocene vegetation and climate characteristics in north-west Turkey: data from the south-western part of the Thrace Basin
    (Tubitak Scientific & Technological Research Council Turkey, 2013) Akgun, Funda; Akkiraz, Mehmet Serkan; Ucbas, Sariye Duygu; Bozcu, Mustafa; Yesilyurt, Sevinc Kapan; Bozcu, Ayse
    In this paper we present the first palynomorph and mollusc assemblages from the sediments in three different sections. From east to west, these are the Sevketiye (northern Biga Peninsula), the Tayfur (Gelibolu Peninsula) and the Kuzu harbour (Gokceada) (parts of the Danismen Formation) sections in the south and south-western side of the Thrace Basin (north-west Turkey), with the aim of obtaining information about the composition and structure of vegetation and climate during the Oligocene. The stratigraphic interval extends from late Rupelian to Chattian. The Danismen Formation in the Sevketiye section yielded a palynomorph association with abundant coastal palms (Arecaceae; Lepidocaryoidae), and mangrove pollen (Pelliciera). A similar assemblage from the Kuzu harbour section was also obtained, with minor contributions of mangrove elements Nypa and Acrostichum aureum, Arecaceae type palm, undifferentiated dinoflagellate cysts and microforaminiferal linings. These palynomorph assemblages, combined with the mollusc data, indicate that low-lying coastal environments prevailed. In contrast, the palynomorphs from the Tayfur section represent a non-marine environment lacking mangrove elements, palm trees, dinoflagellate cysts and microforaminiferal linings. The diversity of angiosperm taxa in the Tayfur palynoflora, which form the bulk of the assemblage, indicates terrestrial vegetation. Quantitative palaeoclimate analyses are based on the Coexistence Approach method, and yield over 22 degrees C at the coast as indicated by mangrove elements and palms in the Sevketiye and Kuzu harbour palynofloras. For the Tayfur palynoflora, mean annual temperature ranged between 16.5 and 21.3 degrees C. This indicates a climate cooling, corresponding to the transition from Rupelian to Chattian, and resulted in the pollen changes from mangrove bearing coastal deposits to more inland vegetation.
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    Organic geochemical characteristics and depositional environment of Lower-Middle Miocene Kucukkuyu Formation, Edremit Gulf, NW Turkey
    (Tubitak Scientific & Technological Research Council Turkey, 2017) Bozcu, Ayse
    The Lower-Middle Miocene Kucukkuyu Formation crops out extensively in the Edremit Gulf area (NW Turkey). In this study, shale samples from this unit were investigated to evaluate source rock characteristics, depositional conditions, and hydrocarbon potential. Outcrop samples of the Kucukkuyu Formation were taken from different locations and analyzed by Rock-Eval pyrolysis, vitrinite reflectance (R-o), stable carbon isotope (delta C-13), total sulfur (TS), gas chromatography (GC), and gas chromatography-mass spectrometry (GC-MS). The total organic carbon (TOC) values range from 0.23 to 6.1 wt.% with an average of 1.76 wt.% for the northern samples and 0.24 to 2.82 wt.% with an average of 1.66 wt.% for the southern samples around the Edremit Gulf. Hydrogen index (HI) values were up to 606 and 712 mg HC/g TOC in the north and south of the gulf, respectively. Organic matter type in the formation consists predominantly of Type II and III kerogen with a minor component of Type I kerogen. Tmax values ranging from 414 to 496 degrees C in the north and 423 to 446 degrees C in the south of the gulf indicate that most samples are at the beginning of the oil generation window and are thermally immature or early-mid-mature. Vitrinite reflectance (R-o) and biomarker maturity parameters support this result. Based on geological observations, biomarker distributions, and TOC/TS ratios, the Kucukkuyu Formation was deposited in a freshwater to slightly brackish water environment under anoxic-suboxic conditions with organic matter input from aquatic organisms and from terrestrial higher plants. According to Rock-Eval pyrolysis data, the Kucukkuyu Formation mostly has medium to good hydrocarbongeneration potential. However, as these potential source rocks are in general immature and/or early-mature, the hydrocarbon potential of the study area is very limited.
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    SOURCE ROCK POTENTIAL OF LOWER-MIDDLE MIOCENE LACUSTRINE DEPOSITS: EXAMPLE OF THE KUCUKKUYU FORMATION, NW TURKEY
    (Estonian Acad Publishers, 2015) Bozcu, Ayse
    The purpose of this study was to examine the geological, stratigraphic and organic geochemical features of the Kucukkuyu Formation out-cropping on Biga Peninsula, NW Turkey. The Lower-Middle Miocene formation crops out around the Gulf of Edremit and near Bayramic-Can in the north of the Kazdag Mountains. The unit is composed of shale, siltstone and sandstone intercalations. The shale is bituminous and represents a potential source rock in the region. Shale samples from the formation were investigated. Rock-Eval pyrolysis, vitrinite reflectance (Ro %), gas chromatography (GC), stable C isotope and total sulfur measurements were carried out. The shale is characterized by high total organic carbon (TOC) values (0.27 to 7.44 wt%, average 1.69 wt%), indicating a good potential source rock. The kerogen types are II and III, indicating the shale to be gas and oil-prone. T-max values are between 352 and 453 degrees C, the average value suggesting early catagenesis. The pristane/ phytane (Pr/Ph) values reveal suboxic and anoxic environments. Carbon preference index (CPI) and C isotope values reveal terrestrial OM. Geological and stratigraphic evaluations and total sulfur (TS) figures indicate that the Kucukkuyu Formation was deposited in a suboxic-anoxic, freshwater environment (lacustrine), developing brackish water conditions from time to time.
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    Source rock potential of the Sayindere formation in the Sambayat oil field, SE Turkey
    (Taylor & Francis Inc, 2019) Duman, Abubekir; Bozcu, Ayse
    Upper Campanian-Maastrichtian Sayindere Formation, located in southeastern Turkey, composed of pelagic limestone which was deposited relatively deep marine. In this study, well samples of the Sayindere Formation were analyzed by Rock-Eval pyrolysis and the oil sample from this unit were analyzed by GC, and GC-MS to assess source rock characteristics and hydrocarbon potential. The TOC values of the Sayindere Formation samples range from 0.34 to 4.65 wt.% with an average of 1.14 wt.% and organic matter have good TOC value. Hydrogen Index (HI) values range from 407 mg HC/g TOC to 603 mg HC/g TOC and indicates Type II kerogen. T-max values are in the range of 434 - 442 degrees C and indicate early-mid mature stage. The Sayindere samples have fair to good hydrocarbon potential based on TOC contents, S2, and PY values. According to the HI versus TOC plot, most of the samples have good oil source. The oil sample contains predominant short-chain n-alkanes and plots in marine algal Type II field on a Pr/n-C17 versus Ph/n-C18 cross-plot indicating anoxic environment. Biomarker analysis shows that the deposition of oil source rock is carbonate-rich sediments. [GRAPHICS] .