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    Adsorption of Cu2+ and Pb2+ ion on dolomite powder
    (ELSEVIER SCIENCE BV, 2009) Pehlivan, Erol; Ozkan, Ali Mujdat; Dinc, Salih; Parlayici, Serife
    Natural Turkish dolomite was shown to be effective for removing Cu2+ and Pb2+ from aqueous solution. Selected information on pH, dose required, initial metal concentration, adsorption capacity of the raw dolomite powder was evaluated for its efficiency in adsorbing metal ions. Dolomite exhibited good Cu2+ and Pb2+ removal levels at all initial metal amount tested (0.04-0.32 mmol, 20 mL). It is important to note that the adsorption capacities of the materials in equilibrium vary, depending on the characteristics of the individual adsorbent, the initial concentration of the adsorbate and pH of the solution. One hour was enough for the removal of metal ions from (0.2 mmol in 20 mL) aqueous solution. Effective removal of metal ions was demonstrated at pH values of 5.0. The adsorptive behavior of dolomite was described by fitting data generated from the study of the Langmuir and Freundlich isotherm models. The adsorption capacity of dolomite was found as 8.26 mg for Cu2+ and 21.74 mg for Pb2+, respectively, from the calculation of adsorption isotherm equation. More than 85% of studied cations were removed by dolomite from aqueous solution in single step. The mechanism for cations removal by dolomite includes surface complexation and ion exchange. (C) 2009 Elsevier B.V. All rights reserved.
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    A Description of Terrestrial Neogene Deposits in the Beykoyu-Gokceyazi Area (Eregli, Konya, Central Turkey)
    (SPRINGER INT PUBLISHING AG, 2014) Ozkan, Ali Mujdat; ComlekcIler, Fuat
    The stratigraphic sequence in the Beykoyu-GokceyazI area, central Turkey, starts with the Palaeocene-lower Eocene Guneydagi Formation, including limestone interbedded with calcirudite, calcarenite, and marl. An angular unconformity separates the unit from the overlying Beykoyu Formation, which has two members: Kabaktepe gypsum and Kayalidagtepe stromatolitic limestone. A Miocene lacustrine environment is inferred for the deposition of the Beykoyu Formation, based on the existence of blue-green algae (Schizothrix sp., Scytonema sp., and Phormidium sp.) as well as green algae (Chara sp.), lacustrine Gastropoda (Planorbarius sp.), and lacustrine ostracodes. The sequence continues with the upper Pliocene-Holocene Kuskuncuk Formation, containing alternations of conglomerate, sandstone, and mudstone, with caliche bands in some levels, which were deposited in alluvial fan and braided stream environments. Quaternary alluvium is the youngest unit in the sequence.
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    Geochemical features of the MenteAYe Formation dolostones (Rhaetian) in the Karacahisar-KasA +/- mlar area (Isparta-Turkey)
    (SPRINGER HEIDELBERG, 2018) Ozkan, Ali Mujdat; Dinc, Salih
    The purpose of this study is to determine the geochemical characteristics of the MenteAYe dolostones (Rhaetian) in the west Taurus Mountains, Turkey. The isotope characteristics of the MenteAYe dolostones show a variation in the delta O-18 values of the dolomites between + 1.35 and - 2.72aEuro degrees (VPDB) and a variation in the delta C-13 values of the dolomites between + 1.6 and + 3.33aEuro degrees (VPDB). Most of the MenteAYe dolostone samples have positive oxygen isotope values; others have weak negative isotope values, which indicate early diagenetic development. In addition, oxygen, carbon, and strontium isotopes and trace element analyses suggest that these dolostones were probably resulted from insignificant recrystallizaion process than chemically similar fluids. Furthermore, Mn/Sr values of the MenteAYe dolostones indicate that there is no significant diagenetic alteration. The total REE contents of the MenteAYe Formation dolostones display a strong positive correlation with Si, Al, Fe, K, Ti, Ba, Rb and negative correlation with Mg, hence REE content is associated with in the first degree titanium-bearing minerals (probably sphene, rutile, anatase), second degree phosphate (apatite), and barium and rubidium-bearing minerals (probably barite). Ce anomalies versus Nd concentrations of the MenteAYe dolostone samples indicate that these dolostones are formed in an anoxic environment. In addition, the K/Rb ratios of the MenteAYe dolostones are not exposed to any metamorphism and indicate some diagenetic alteration. Calculated temperature values using delta O-18 values of the MenteAYe dolostones yield precipitation temperatures of 17 to 42 A degrees C, and suggest burial depths of 67 to 900 m. Sources of magnesium for dolomitization of the MenteAYe Formation carbonates were most likely fluids from seawater and/or diagenetic brines (slightly modified seawater). The MenteAYe dolostones formed as early diagenetic (Rhaetian to Cenomanian) in shallow burial areas at lower temperatures than seawater and/or diagenetic brines (slightly modified seawater).
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    Petrographic and geochemical features of the dolostones at the Golbogazi Formation (Upper Devonian), Southwest Konya, Turkey
    (SPRINGER HEIDELBERG, 2017) Ozkan, Ali Mujdat; Bicer, Emre
    This paper describes the occurrence of dolostone and the mechanism of dolomitization of the Upper Devonian Golbogazi Formation in the allochthonous Taurus Mountains Aladag unit in Turkey. The Upper Devonian Golbogazi Formation carbonates, with dominant ostracod-bearing mudstone and wackestone, formed tidal and subtidal environments, and some of these rocks were dolomitized from shallow to deep burial. On the basis of the field, the petrographic and geochemical features, four different replaceable and cement dolostone phases have been recognized. The replacive dolostones contain (1) very fine to fine crystalline planar-s dolostone (df1), (2) medium to coarse crystalline planar-s to planar-e dolostone (df2), (3) coarse to very coarse crystalline non-planar-a dolostone (df3), and (4) coarse to very coarse crystalline planar dolostone cement (df4). The replacive dolostones are disordered to moderate the ordered and calcium-rich. They are non-stoichiometric and have 46-59 mol% CaCO3 and 41-54 mol% MgCO3 total contents. The df1 dolostones have MgCO3 contents of 41-54 mol%, the df2 dolostones have 41-53 mol%, the df3 dolostones have 49 mol%, and the df4 dolostones have 49-50 mol%, respectively. The Golbogazi dolostones have delta O-18 values of -9.44 to -2.20% Vienna Pee Dee Belemnite (VPDB) and d13C values of -1.58 to + 2.52 VPDB. Sr, Na, Mn, and Fe concentrations of replacive dolostones are 74-184, 148-593, below detection level (bdl)-619, and 1049-9233 ppm, respectively. The petrographic and geochemical data demonstrate that the replacive dolostones occurred prior to the chemical compaction at shallow to intermediate burial depths from Late Devonian seawater and/ or seawater lightly modified by water-rock interaction process and later recrystallized by basinal brines at increasing burial depths and temperature. The North American Shale Composite-normalized rare earth element values of both limestone and dolostone show very similar rare earth element patterns characterized by slightly or considerably negative cerium (Ce) anomalies and a clear depletion in all rare earth element species. The dedolomitization observed in the Golbogazi Formation is thought to occur by the oxidizing effect of the meteoric water in the shallow burial environment during the telodiagenesis.
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    SEDIMENTARY CHARACTERISTICS OF THE DIKMENDEDE FORMATION (ANKARA, TURKEY)
    (INT SCIENTIFIC CONFERENCE SGEM, 2011) Ozkan, Ali Mujdat; Bozdag, Ayla
    The Maastrichtian aged Dikmendede Formation in the Orhaniye (Kazan-Ankara) area formed in a deep-marine environment. The formation consists of alternating green, grey-coloured turbiditic conglomerate, sandstone, shale, claystone and marl. The unit has typical flysch features and has sedimentary structures such as thin/thick bedding, normal graded bedding, erosional surfaces, flute casts, load structures, ball-and-pillow structures, bounce marks, slump structures and numerous biogenic traces. The conglomerates of turbiditic channel fills display clast imbrication and graded bedding. The sandstones of the Dikmendede Formation are mainly made of quartz, plagioclase, alkali feldspar (orthoclase, microcline, sanidine), sedimentary (carbonate, chert, sandstone, shale), metamorphic (micaschist, quartzschist, calcschist, phyllite, gneiss), volcanic rock clasts, mica (muscovite, biotite), heavy minerals (epidote, opaque minerals, glaucophane, piroksen, rutile, turmaline). The sandstones, texturally and mineralogically immature, are cemented by calcite and iron-oxides, in addition to clayey (illite, smectite, chlorite) and in a lesser amount micritic matrix.
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    SEDIMENTOLOGY OF BEYKOYU FORMATION (MIOCENE) AROUND BEYKOYU-KUSKUNCUK-GOKCEYAZI (EREGLI-KONYA-TURKEY)
    (INT SCIENTIFIC CONFERENCE SGEM, 2008) Ozkan, Ali Mujdat
    The basement of the investigated area consists of Upper Permian - Upper cretaceous aged the Bolkardagi Group and several formations situated in the Bolkardagi Unit, tectonostratigraphic units of the Taurus, viz., Paleocene - Lower Eocene aged the Guneydagi formation, and Upper Paleocene - Eocene aged the Halkapinar fort-nation. The limestone of the Guneydagi formation is observed as a basement rock in the area, and is overlied with angular unconformity by Miocene aged the Beykoyu formation, which is made up of members of the Kabaktepe gypsum and the Kayalidagtepe stromatolitic limestone. The Beykoyu formation is overlied with an angular unconformity by Upper Pliocene - Holocene aged the Kuskuncuk formation, which consists of alternation of conglomerate, sandstone and mudstone including caliche bands in some levels. While the Beykoyu formation was formed in lacustrine environment, the Kuskuncuk formation was developed in environments of alluvial fan and braided stream. The Kabaktepe gypsum member, basement of the Beykoyu formation, is white - gray in colour and is usually massive, rondomly medium to thick strata and have a laminae. The gypsum of the Kabaktepe gypsum member is usually white in colour and cyrstalized texture, at some levels they are prismatic and transparent, and folded in places. At some places, at the bottom of the gypsum, alternating of conglomerate - sandstone and mudstone can be observed. Through the upper part, the alternating of greenish - gray, brown sandstones and green - red coloured mudstones are present. In the upper levels they are in the form of gypsum with muddy stone interlayer. Over the gypsum, stromatolitic limestones belonging to the Kayalidagtepe member are found. The stromatolites are beige, brown in colour, medium to thick layered, and these are in the types of lateral linked hemispheroidal (LLH type), stacked hemispheroidal (SH type) and onkoides (SS type). The stromatolitic limestones have interlayering gray mudstones, red conglomerate, sandstones and mudstones. In some levels the stromatolites can be seen as sandy - gravel limestones which have ostrocode and gastropoda fossiliferous limestones alternating with marts. The formation of stromatolitic limestones belonging to the Kayalidagtepe member is strictly depending on the blue - green algae of Shizothrix sp., Phormidium sp. and Scytonema sp.
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    Stratigraphic Features of the Yesilyurt-Konak Area (Malatya, Turkey)
    (SPRINGER INT PUBLISHING AG, 2014) Ozkan, Ali Mujdat
    The stratigraphic sequence in the study area starts with the Carboniferous-Triassic Malatya Metamorphics, which are composed of marble and schist and covered unconformably by the Maastrichtian Gunduzbey Group. The group includes the Kizilguney Formation with conglomerate and sandstones, and the Kapullu Formation containing limestone-marl alternations, with turbiditic sandstone intercalations. The sequence continues with the Lutetian Yesilyurt Group, which includes the Zorbon, Yukaribanazi, and Gedik Formations, unconformably overlying the Kapullu Formation. The Zorbon Formation is composed of conglomerate interbedded with sandstone and mudstone, whereas the Yukaribanazi Formation consists of sandstone and shale alternations with intercalations of conglomerates and olistoliths. The Gedik Formation is composed of reefal limestone, claystone, and marl, and underlies the Pliocene-Quaternary Beylerderesi Formation formed of conglomerate interbedded with sandstone. Holocene alluvium unconformably overlies all units in the region.