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Öğe Paleoclimatic interpretations of the late Miocene/pliocene Kömüşini formation, Central Turkey: Paleosol and fluvial succession(International Multidisciplinary Scientific Geoconference, 2015) Gürel A.The late Miocene/Pliocene was characterized by high global temperatures (the Messinian salinity crisis), and during this epoch went the Mediterranean Sea into a cycle of partly or nearly complete desiccation throughout the latter part of the Messinian age. The marine Mediterranean Sea area has been studied from widely different perspectives. However, continental paleoenvironmental and paleoclimatic records of the late Miocene surrounding the Mediterranean area are very limited in their spatial extent. The study area (Konya-Kulu) is situated in northwestern part of the Tuzgölü basin in Central Anatolia, which is the largest intermontane basin in Turkey [1]. The paleosols and fluvio-lacustrine sedimentary rocks (conglomerate, sandstone and limestone) of Kömişini Formation were described in detail and analyzed for geology, mineralogy, and these were characterized using petrographic and scanning electron microscope (SEM), X-ray diffractometry (XRD). Paleosols occurs in sequences with in the whole stratigraphic profile. It is recognized that they are histosol, aridisols, inceptisols, locally associated with, oxisols, according to the soil taxonomy [2]. Red colored palaeosols formed within these terrestrial sedimentary rocks under near surface or surface conditions, and comprise predominantly of quartz, feldspar, opal-CT, serpentine, calcite, dolomite, gypsum, hematite and clay minerals, such as smectite, chlorite, palygorskite and illite. Gypsum, smectite and chloride dominate at the base of the profile, whereas the palygorskite increase upward of the sections. The sedimentary rocks such as, conglomerate, sandstone and limestone formed in fluvio-lacustrine environment. The alteration of the ophiolitic and carbonate rich basement rocks caused the depletion of SiO2, Al2O3+Fe2O3, TiO2 and K2O by the precipitation of palygorskite, smectite, chlorite, ± illite in palaeosols. The appearance of limestone and palygorskite from the upper profile level is suggestive of a shift to more arid or more seasonal conditions that is equivalent with a prominent change in sediment provenance and these indicate decrease in sedimentation rate during the latter part of the late Miocene/Pliocene. © SGEM2015.Öğe Physicochemical properties and availability of Tahar-Güzelöz (Nevşehir) diatomite(General Directorate of Mineral Research and Exploration (MTA), 2018) Yildiz A.; Gürel A.; Okutan D.In this study, utilization of Tahar-Güzelöz (Nevşehir) diatomites occurring within the late Miocene-Pliocene age vocanosedimentary units which formed due to volcanism and outcropping in Tahar and Güzelöz (Nevşehir) areas were investigated. In the study area, three stratigraphic sections were measured, one of which was measured in the Tahar area (TK), and the two others were measured in the Güzelöz area (GÜ1 and GÜ2). Various physicomechanical, chemical, mineralogical and analytical methods were used on the samples. Analyses results of the diatomites in the investigated area were determined as follow; amount of acid-insoluble matters; 74,20 - 84,20 %, amount of water-insoluble matters; 99,80 %, loss on ignition ratios (950 °C de); 8,18 - 22,82 %, whitenesses; 80,45 - 84,79 %, particle sizes; 0,7-209 µ, pore sizes; 1,448 e-03A – 5,888 e-04A, pore volumes; 1,148 e-02 – 8,515 e-02 cc/g, specific gravities; 2,33 – 2,49 gr/cm3 , total porosities; 57 –60 %, cumulative specific surface areas; 4,047 e+01 – 5,160 e+01 m2/g, pH; 5-7 (acit and neutral), filtration rates; 138 – 351 ml/dk, SiO2 contents; 38,16 – 67,77 %. It was determined that, the samples are not contain palinological material and these generally formed from long and large diatom genus and species. The evaluation of the analyses results showed that, none of the three location’s diatomites is suitable as construction material, carrier, mild abrasive and cleaner, isolution material. At the same time, determined that, the Tahar and Güzelöz–1 location’s diatomites can not be used as filler material. In addition, it was determined that, the subject diatomites can be used in the manufacture of silicate, and in percolator by the enrichment in terms SiO2 . Also, Güzelöz-2 location’s diatomites can be used as filler material in the rubber and paper industries. © 2018 General Directorate of Mineral Research and Exploration (MTA). All rights reserved.Öğe Physicochemical properties and uses of Karacaören area (Nevşehir) diatomite(General Directorate of Mineral Research and Exploration (MTA), 2016) Yildiz A.; Gürel A.; Dursun Y.G.In this study, physicochemical properties and the area of use of diatomites that occur in association with Central Anatolian volcanism in the Karacaören region (Ürgüp country, Nevşehir) are investigated. In the investigated area two stratigraphic sections were measured, one is in Quaternary lake units (K1) and another section is in the lacustrine sediments of Bayramhacili member within Ürgüp formation of late Miocene-Pliocene age (K2). In order to specify physicochemical properties and the area of use of diatomites, various analyses were carried out at the Laboratories of General Directorate of Mineral Research and Exploration including loss on ignition (at 1050 °C), XRD, amount of acid and water-insoluble matter, thermal conductivity (in the range of 101; 150 °C and ± 10 °C), XRF, pH, total porosity, specific gravity, specific surface area, pore volume, pore size, whiteness, particle size and SEM analysis. The evaluation of the analyses results showed that the studied diatomites have a commercial value and can be used directly in percolator, as filler and structuring agents and in silicate manufacturing. In addition, once processed, they can also be used as mild abrasive and cleaner in production of isolation material.Öğe Sedimentological characteristics of the Çukurbag Formation deposited along the Ecemis Fault Zone, Central Anatolia, Turkey(2007) Gürel A.; Çiftçi E.; Kerey I.E.The Oligocene Çukurbag Formation, deposited within a long narrow basin surrounded by the Aladag, Ulukisla, and Nigde metamorphic Groups, consists of conglomerate, sandstone, siltstone, mudstone, marl, mudstone-gypsum successions. A number of analytical methods including morphological, mineralogical, and chemical techniques were employed to investigate the sedimentological characteristics of the formation. According to the grain size analyses, sediments of the formation are very poorly sorted with strong positive to near symmetrical skewness. The analyses show that irregular flow regime should have occurred during sedimentation of the Çukurbag Formation. These sediments comprises mainly of quartz, feldspars, calcite, clinopyroxene, and Fe-oxides. Common clay minerals include smectite, chlorite, and kaolinite. The chemical analyses carried out on the samples representing the bottom to the top of the formation indicated that SiO2, Al2O3, K2O, and P2O5 contents are low compared to the world mudstone averages. However, MgO, CaO, and C contents are comparatively high. Four measured profiles showing the distribution of principle facies within the formation are prepared. Based on the profile analyses, seven distinct lithological facies were distinguished that include massive conglomerate, bedded conglomerate, stratified sandstone, cross-bedded sandstone, laminated siltstone, massive mudstone-marl, and laminated mudstone-gypsum. This study suggests that the sediments of this formation must have been reworked material transported from unknown distances and deposited in an alluvial fan-braided stream and lacustrine environments. © Geol. Soc. India.Öğe Weathering of gabbroic rocks in the central black sea area (Ordu) and formation of acid soils [Orta karadeniz bölge’sinde (Ordu) yer alan gabroik kayaçların ayrışması ve asidik toprakların oluşumu](Namik Kemal University - Agricultural Faculty, 2017) Gürel A.The study area is located in forest soils in and around Yeşilköy village of Ordu. It is observed that the ratio of sand and clay in soil horizons developed on gabbro increased with the depth of the profile. The mineralogical studies carried out on gabbro indicate that the amount of quartz minerals in upper horizons of the soil increased, but that the amount of feldspar, pyroxene, amphibole and olivine minerals decreased. The soil horizons developed on gabbro, the amount of oxides such as Al2O3, Fe2O3 and MnO were increased and CaO, MgO, Na2O, K2O and P2O5 decreased with respect to host rock. It is observed that in this locality, the mobile trace elements such as Co, Sr and Cd were leached vertically, the semi mobile trace elements such as Cu, Ni, Ba and Zn, are leached away completely and the immobile trace elements such as Cr, Nb, Ce, and Zr were concentrated in soil profile. The data obtained from this locality is in the range of the North American Shale Composite (NASC). © 2017 Namik Kemal University - Agricultural Faculty. All Rights Reserved.
