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    C, O, S and Sr isotope studies on the genesis of Fe-carbonate and barite mineralizations in the Attepe iron district (Adana, Southern Turkey)
    (ELSEVIER GMBH, URBAN & FISCHER VERLAG, 2007) Kuepeli, Suayip; Karadag, A. Muzaffer; Ayhan, Ahmet; Doeyen, Adnan; Arik, Fetullah
    The Attepe district consists of Precambrian, Lower-Middle Cambrian, Upper Cambrian-Lower Ordovician and Mesozoic formations. It contains several iron deposits and occurrences. Three types of iron-mineralizations can be distinguished in the area; (1) Sedimentary Fe-sulfide in Precambrian bituminous metapelitic rocks, and Fe-oxides in Precambrian metasandstones (STSO), (ii) vein-type Fe-carbonate and oxides composed of mainly siderite, ankerite and hematite including barite in Lower-Middle Cambrian metacarbonates of the Caltepe Formation (HICO), (iii) karstic Fe-oxides and hydroxides essentially in the Lower-Middle Cambrian metacarbonates and the unweathered Fe-carbonates (KIO). The latter type is more widespread and located at the upper parts of the most important mineable iron deposits like Attepe deposit. Oxygen-, carbon-, sulfur- and strontium-isotope studies have been performed on siderites and barites in the vein-type ores, and on calcites in the recrystallized Caltepe Limestones to investigate the sources and formation mechanism of primary ore-forming constituents. The delta C-13 values of siderites and calcites in limestones of the Caltepe Formation range from -10.10 parts per thousand to -8.20 parts per thousand, and from -0.8 parts per thousand to 2.30 parts per thousand. Both carbonate minerals show delta O-18 values between 17.50-18.30 parts per thousand and 16.20-23.00 parts per thousand, respectively. The delta C-13 and delta O-18 isotopic variations do not indicate any direct or linear relations between siderites and limestones. However, it is possible that the carbon and oxygen isotopic compositions of carbonate minerals could be changed to some extent, when limestones were subjected to hydrothermal processes or thermal alterations during metamorphism. The isotopic values of barites display 32.40-38.30 parts per thousand for delta S-34 and 12.20-14.70 parts per thousand for delta O-18. The strontium isotope ratios (0.717169-0.718601) of barites and the sulfur isotope compositions of barites and pyrites suggest that there are no direct linkages of ore-forming compounds neither with a magmatic source nor with sedimentary pyrite formations in the Precambrian bituminous shales of the Attepe formation. According to the field observations and the stable isotope data, siderites and ankerites should be formed by interaction between iron-rich hydrothermal fluids and Caltepe limestones, whereas isotope ratios of barites indicate that they were formed by mixing of sulfur-rich meteoric waters and deeply circulated hydrothermal solutions. (C) 2006 Elsevier GmbH. All rights reserved.
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    GEOLOGICAL INVESTIGATION OF THE CARIKSARAYLAR-KOZLUCAY AREA (ISPARTA-TURKYE)
    (INT SCIENTIFIC CONFERENCE SGEM, 2008) Bozkir, Yesim; Ayhan, Ahmet; Arik, Fetullah
    The study area is located in southeastern part of Sultandaglari, 50 km to the northeast of Isparta. The geological units exposed in the area are: The Lower-Middle Cambrian Caltepe Formation, which comprises grey and pink coloured recrystallized limestone, nodular limestone, dolomitic limestone and dolomite, is the oldest unit. The Upper Cambrian - Lower Ordovician Seydisehir Formation conformably overlies the Caltepe formation and comprises green to brown coloured metasandstone, quartzite, phyllite, calcshists, schist. The Upper Jurassic Mezardere formation lies with an angular unconformity on the Seydisehir Formation and comprises dolomite, dolomitic limestone and limestone. The Upper Jurassic Islikayatepe volcanite is composed of volcanite, partly weathered volcanite and autochthonous bauxite. The bauxite occurrences are aligned generally in NW-SE direction and seen in two or three levels depending on the localities. The Upper Cretaceous Aktassirti limestone consists mainly of limestone with dolomitic level. The Miocene lacustrine Bagkonak formation consists of cream and orange coloured, poorly sorted conglomerates, mudstones, claystones, sandstones and sandy limestones. Locally Recent alluvium is seen.
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    GEOLOGICAL SETTING AND PETROGRAPHICAL CHARACTERISTICS OF THE BOZKIR OPHIOLITIC MELANGE, BOZKIR (KONYA- TURKIYE).
    (INT SCIENTIFIC CONFERENCE SGEM, 2008) Ozturk, Alican; Karadag, M. Muzaffer; Ayhan, Ahmet; Arik, Fetullah
    [Abstract not Available]
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    Rare earth element (REE) geochemistry and genetic implications of the Mortas bauxite deposit (Seydisehir/Konya - Southern Turkey)
    (ELSEVIER GMBH, URBAN & FISCHER VERLAG, 2009) Karadag, M. Muzaffer; Kupeli, Suayip; Aryk, Fetullah; Ayhan, Ahmet; Zedef, Veysel; Doyen, Adnan
    The Mediterranean-type karst-bauxite deposit of Mortas, South Turkey, placed unconformably between Cenomanian and Senonian shallow marine limestones is built of massive (MB), oolithic (OB), breccia-bearing (BB) and earthy (EB) bauxite horizons, from top to bottom. The MB layer is enriched in Al and REE (except Cc) due to loss of Si, Na, K, Mg and P. REE are accumulated in the BB but depleted in the EB layers. The ferruginous OB lost LREE and gained in HREE probable due to scavenging by authigenic heavy minerals like rutile, anatase and titanite. Total REE contents in the bauxite profile display an increasing trend from bottom to top, while negative and maximum positive Ce anomalies characterize the upper and the lower parts of the profile, respectively. This unusual REE behavior is explicable by assuming mobilization of Ce(W) either under reducing condition or chemical complexation under alkaline conditions in the top layer and scavenging of Cc by Al-Mg hydrosilicates and Ti-oxides and/or precipitation with authigenic REE minerals, especially of the bastnasite group near the bedrock limestones. Similarity in chondrite normalized-REE patterns of the Seydisehir phyllites, bauxite and terra rossa samples and the presence of tridymite (?) in bauxites makes a felsic source rock most likely and reveal a close genetic relationship between the Seydisehir phyllites and the recent terra rossa occurrences. The REE patterns of the bauxites resemble those of the Katrangedigi limestone despite variations in Sigma REE. Field observations and geochemical data together with mass-balance calculations suggest that the Mortas deposit was derived from the Seydisehir phyllites and argillic phase within the Katrangedigi limestone which in turn have Precambrian (?) felsic, probably granitic precursors. (c) 2008 Elsevier GmbH. All rights reserved.