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2013

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The U-Pb Age, Geochemistry And Tectonic Significance Of Granitoids In The Soursat Complex, Northwest Iran, Mahboobeh Jamshidi Badr, Alan S. Collins, Fariborz Masoudi, Grant Cox, Mohammad Mohajjel Jan 2013

The U-Pb Age, Geochemistry And Tectonic Significance Of Granitoids In The Soursat Complex, Northwest Iran, Mahboobeh Jamshidi Badr, Alan S. Collins, Fariborz Masoudi, Grant Cox, Mohammad Mohajjel

Turkish Journal of Earth Sciences

The Soursat Complex in northwestern of Iran is part of the Sanandaj-Sirjan metamorphic belt. Three granitoid suites are present: Type I- syenogranite and deformed syenogranite; Type II- Turkeh Dare and Pichagchi plutons; and Type III- quartz porphyry. The granites can be assigned to a medium-K calc-alkaline to high-K calc-alkaline series. The Type I granitoids are weakly to strongly peraluminous and belong to a S-type suite, whereas Type II plutons are metaluminous to weakly peraluminous with I-type character. Type III granitoids are weakly peraluminous and can be labelled as a highly fractionated I-type suite. U/Pb zircon dating of the syenogranite and …

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Petromodeler (Petrological Modeler): A Microsoft® Excel© Spreadsheet Program For Modelling Melting, Mixing, Crystallization And Assimilation Processes In Magmatic Systems, Emrah Yalçin Ersoy Jan 2013

Petromodeler (Petrological Modeler): A Microsoft® Excel© Spreadsheet Program For Modelling Melting, Mixing, Crystallization And Assimilation Processes In Magmatic Systems, Emrah Yalçin Ersoy

Turkish Journal of Earth Sciences

PETROMODELER (Petrologic Modeler) is a Microsoft® Excel© spreadsheet program which numerically and graphically models magmatic processes including melting, crystallization, assimilation and mixing by using trace elements and isotopic ratios. Melting models include (a) batch, (b) dynamic (continuous) and (c) fractional melting for (1) instantaneous and (2) cumulate melts, (3) residual solid and (4) total residue. These models can also be used to treat modal and non-modal melting. Crystallization processes modelled in the program include: (1) perfect equilibrium and (2) perfect fractional crystallization (PEC and PFC), (3) equilibrium crystallization-imperfect fractional crystallization (EC-IFC), (4) zoned crystallization-imperfect fractional crystallization (ZC-IFC), and (5) combined …

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Emerging Multi-Proxy Records Of Late Quaternary Palaeoclimate Dynamics In Turkey And The Surrounding Region, Kathleen Nicoll, Ceren Küçükuysal Jan 2013

Emerging Multi-Proxy Records Of Late Quaternary Palaeoclimate Dynamics In Turkey And The Surrounding Region, Kathleen Nicoll, Ceren Küçükuysal

Turkish Journal of Earth Sciences

We present an overview of selected papers published since 2000 that interpret Late Quaternary multi-proxy palaeoclimate records from Turkey and the surrounding region of the Near-Middle East and Mediterranean region. Existing records in Turkey are rather limited in their resolution, and the locations studied thus far reflect a limited spatial and temporal distribution. Because Turkey is a very large country with numerous mountains that affect local weather conditions and create complex feedbacks, it is difficult to correlate trends across the broad landscape, and beyond. Published instrumental records are too short, and most palaeoclimate proxy records, including many lakes studied in …

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Petrology, Geochemistry, And Evolution Of The Iron Skarns Along The Northern Contact Of The Eğrigöz Plutonic Complex, Western Anatolia, Turkey, Tolga Oyman, İsmet Özgenç, Murat Tokcaer, Mehmet Akbulut Jan 2013

Petrology, Geochemistry, And Evolution Of The Iron Skarns Along The Northern Contact Of The Eğrigöz Plutonic Complex, Western Anatolia, Turkey, Tolga Oyman, İsmet Özgenç, Murat Tokcaer, Mehmet Akbulut

Turkish Journal of Earth Sciences

The Çatak and Küreci skarn districts are located approximately 10 km NW of Emet (Kütahya) in Western Turkey. The skarn and associated ore formations mainly occur at the contact between intrusive rocks of the Eğrigöz Plutonic Complex (EPC) and calcareous pelitic schists with limestone lenses of the Sarıcasu Formation and meta-carbonate rocks of the Arıkaya Formation. The major, trace, and rare earth element analysis of the igneous rocks indicate that they are high level, subalkaline, calc-alkaline, peraluminous to metaluminous I-type intrusions, generated in a continental arc setting. Three distinct skarn-type mineralization, differing in their host rocks and distance from the …

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Cover And Contents Jan 2013

Cover And Contents

Turkish Journal of Earth Sciences

No abstract provided.

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Genesis Of Sedimentary- And Vein-Type Magnesite Deposits At Kop Mountain, Ne Turkey, Selahatti̇n Kadi̇r, Hasan Kolayli, Muhsi̇n Eren Jan 2013

Genesis Of Sedimentary- And Vein-Type Magnesite Deposits At Kop Mountain, Ne Turkey, Selahatti̇n Kadi̇r, Hasan Kolayli, Muhsi̇n Eren

Turkish Journal of Earth Sciences

Sedimentary- and vein-type magnesites were deposited within and on ultramafic rocks of the Kop Mountain region in Bayburt province. In the field, magnesites are exposed along NE-SW trending normal faults and in fractures in the ultramafic rocks. Petrographic studies reveal that magnesite is predominantly micrite, but also occurs as microsparite formed by recrystallization of micrite. The ultramafic rocks hosting the magnesites consist of serpentinized olivine, hypersthene and diopside. Ni, Co and Ti contents of magnesites suggest precipitation from percolating water through the serpentinized ultramafic rocks. The sedimentary- and vein-type magnesites have different \delta^{18}O and \delta^{13}C values, characterizing formation under different …

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Late Maastrichtian-Late Palaeocene Planktic Foraminiferal Biostratigraphy Of The Matrix Of The Bornova Flysch Zone Around Bornova (İzmir, Western Anatolia, Turkey), Bi̇lal Sari Jan 2013

Late Maastrichtian-Late Palaeocene Planktic Foraminiferal Biostratigraphy Of The Matrix Of The Bornova Flysch Zone Around Bornova (İzmir, Western Anatolia, Turkey), Bi̇lal Sari

Turkish Journal of Earth Sciences

The Bornova Flysch Zone (BFZ), located between the Menderes Massif and the İzmir-Ankara Suture in westernmost Anatolia (Turkey), forms the westernmost part of the Anatolide-Taurides. The BFZ comprises intensely sheared Upper Cretaceous-Palaeocene matrix and blocks of various origins. The matrix of the BFZ is mainly made up of unfossiliferous flysch-type sediments (alternations of sandstones and shales). In Bornova (İzmir, western Turkey) and its surroundings, these clastics locally include planktic foraminifera-bearing pelagic micritic limestone and calcareous shale lenses and interbeds (Beytitepe Limestone). As a result of studies focusing on the planktic foraminifera-bearing pelagic interlayers in three areas (Gökdere, Işıklar and Kocaçay …

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The Efficacy Of Travertine As A Palaeoenvironmental Indicator: Palaeomagnetic Study Of Neotectonic Examples From Denizli, Turkey, Beki̇r Levent Mesci̇, Orhan Tatar, John D. A. Piper, Hali̇l Gürsoy, Erhan Altunel, Stephen Crowley Jan 2013

The Efficacy Of Travertine As A Palaeoenvironmental Indicator: Palaeomagnetic Study Of Neotectonic Examples From Denizli, Turkey, Beki̇r Levent Mesci̇, Orhan Tatar, John D. A. Piper, Hali̇l Gürsoy, Erhan Altunel, Stephen Crowley

Turkish Journal of Earth Sciences

This study has aimed to evaluate whether a discernible environmental signature is recorded in tectonic travertine by applying palaeomagnetic study to examples from the Denizli region in western Turkey. Palaeomagnetic sampling in 7 quarry exposures through short stratigraphic intervals of bedded travertine has determined variations in magnetic susceptibility and palaeofield direction; the former is a potential proxy of climatically-controlled atmospheric dust input and the latter is a possible indicator of directional changes resulting from geomagnetic secular variation of the ancient magnetic field and hence a measure of the rate of travertine accretion. Most sites record normal polarity as predicted from …

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Microfacies Correlation Analysis Of The Oligocene-Miocene Asmari Formation, In The Central Part Of The Rag-E-Safid Anticlinal Oil Field, Zagros Basin, South-West Iran, Mahnaz Amirshahkarami Jan 2013

Microfacies Correlation Analysis Of The Oligocene-Miocene Asmari Formation, In The Central Part Of The Rag-E-Safid Anticlinal Oil Field, Zagros Basin, South-West Iran, Mahnaz Amirshahkarami

Turkish Journal of Earth Sciences

The Oligocene-Miocene Asmari Formation was deposited in a carbonate ramp setting at the margin of the Zagros Basin in south-western Iran. The subsurface sedimentary successions of the Asmari Formation have been studied using cores from the Rag-e-Safid oil field, in order to determinate their microfacies and sedimentary palaeoenvironments. Based on texture analysis and faunal assemblages, 10 microfacies types have been recognised and interpreted. They indicate different depositional settings: open marine, oolitic and bioclastic shoal, lagoon, tidal flat and beach. The microfacies have been interpreted as indicative of the inner and middle ramp. In accordance with the temporal and spatial correlation …

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Revised Late Campanian-Danian Age Of The Melange-Related Turbiditic Sequence In The Mersin Area (Central Taurides, S. Turkey), Hayati̇ Koç, Kemal Tasli, Erol Özer Jan 2013

Revised Late Campanian-Danian Age Of The Melange-Related Turbiditic Sequence In The Mersin Area (Central Taurides, S. Turkey), Hayati̇ Koç, Kemal Tasli, Erol Özer

Turkish Journal of Earth Sciences

A planktonic foraminiferal assemblage obtained from the Yavca stratigraphic section north of Mersin shows that the age of a melange-related turbiditic sequence extends to the Danian (Early Palaeocene). Previously, this turbiditic sequence, termed the Yavca Formation, was considered to be of Late Cretaceous or Campanian-Maastrichtian age. The formation is either depositionally overlain by the Fındıkpınarı ophiolite-related melange or tectonically by Mersin Ophiolite slices or Jurassic-Cretaceous platform carbonates. Clayey limestone and mudstone samples collected from the type area of the Yavca Formation yielded planktonic foraminiferal assemblages, which include Parasubbotina pseudobulloides (Plummer), P. varianta (Subbotina), Praemurica pseudoinconstans (Blow), P. inconstans (Subbotina), Globanomalina …

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Prediction Of Weathering Development In Metarhyolites Of The Ilgın (Konya) Area, Sw Turkey, Erkan Bozkurtoğlu, Şenel Özdamar, Hati̇ce Ünal Ercan Jan 2013

Prediction Of Weathering Development In Metarhyolites Of The Ilgın (Konya) Area, Sw Turkey, Erkan Bozkurtoğlu, Şenel Özdamar, Hati̇ce Ünal Ercan

Turkish Journal of Earth Sciences

Fresh to weathered metarhyolites crop out in the Ilgın (Konya) area of the Afyon-Bolkardağ Zone. Determination of the development of weathering was studied by physical (i.e. specific gravity, dry unit weight, saturated unit weight, porosity, void ratio, and degree of saturation by weight) and mechanical (i.e. point load) properties and the \"point rock change value\" (RCV_p) and \"point rock change ratio\" (RCR_p) values of the metarhyolite rock samples. The samples were classified in 3 groups (i.e. A, B, and C) representing degree of weathering from weathered to fresh rocks based on their RCV_p and RCR_p values. The K_2O values are …

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Coeval Shoshonitic-Ultrapotassic Dyke Emplacements Within The Kestanbol Pluton, Ezine – Biga Peninsula (Nw Anatolia), Cüneyt Akal Jan 2013

Coeval Shoshonitic-Ultrapotassic Dyke Emplacements Within The Kestanbol Pluton, Ezine – Biga Peninsula (Nw Anatolia), Cüneyt Akal

Turkish Journal of Earth Sciences

The Biga Peninsula, in the north-western part of Western Anatolia, is part of the Sakarya Zone of the Western Pontides and the tectonically overlying Ezine group. The basement rocks are intruded by the early Miocene Kestanbol Pluton and early to middle Miocene calc-alkaline to shoshonitic-ultrapotassic volcanic successions related to postcollisional continental extension. The Kestanbol Pluton mainly comprises monzonite and granodiorite and is cut by shoshonitic-ultrapotassic tephriphonolite dykes. ^{40}Ar-^{39}Ar ages of biotite (21.22 ± 0.09 Ma) and leucite (22.21 ± 0.07 Ma) crystals indicate that tephriphonolite dyke emplacement was coeval with the intrusion of the Kestanbol Pluton during the early Miocene …

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Oligocene Vegetation And Climate Characteristics In North-West Turkey: Data From The South-Western Part Of The Thrace Basin, Funda Akgün, Mehmet Serkan Akki̇raz, Sari̇ye Duygu Üçbaş, Mustafa Bozcu, Sevi̇nç Kapan, Ayşe Bozcu Jan 2013

Oligocene Vegetation And Climate Characteristics In North-West Turkey: Data From The South-Western Part Of The Thrace Basin, Funda Akgün, Mehmet Serkan Akki̇raz, Sari̇ye Duygu Üçbaş, Mustafa Bozcu, Sevi̇nç Kapan, Ayşe Bozcu

Turkish Journal of Earth Sciences

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 Şevketiye (northern Biga Peninsula), the Tayfur (Gelibolu Peninsula) and the Kuzu harbour (Gökçeada) (parts of the Danişmen 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 Danişmen Formation in the Şevketiye section yielded a palynomorph association with abundant coastal palms (Arecaceae; Lepidocaryoidae), …

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Tragulidae (Artiodactyla, Ruminantia) From The Middle Miocene Chinji Formation Of Pakistan, Muhammad Akbar Khan, Muhammad Akhtar Jan 2013

Tragulidae (Artiodactyla, Ruminantia) From The Middle Miocene Chinji Formation Of Pakistan, Muhammad Akbar Khan, Muhammad Akhtar

Turkish Journal of Earth Sciences

The fossil record of the Siwalik tragulids remains poorly documented. The study of the tragulid material from the Chinji Formation allows the identification of 3 species: Dorcatherium minus, Dorcatherium majus and Dorcabune anthracotherioides. The tragulid assemblage is quite rich and Dorcatherium is the predominant taxon in the Chinji Formation of Pakistan. The fossils from the Chinji Formation of the Chakwal district, northern Pakistan, may document the first appearance of the 3 tragulid species in the Lower Siwaliks. The selenodonty and palaeoecology of the Siwalik tragulids are also discussed.

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Comment On "Al-In-Hornblende Thermobarometry And Sr-Nd-O-Pb Isotopic Compositions Of The Early Miocene Alaçam Granite In Nw Anatolia (Turkey)", Si̇bel Tatar Erkül, Fuat Erkül Jan 2013

Comment On "Al-In-Hornblende Thermobarometry And Sr-Nd-O-Pb Isotopic Compositions Of The Early Miocene Alaçam Granite In Nw Anatolia (Turkey)", Si̇bel Tatar Erkül, Fuat Erkül

Turkish Journal of Earth Sciences

No abstract provided.

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The Effects Of Linear Coarse-Grained Slope Channel Bodies On The Orientations Of Fold Developments: A Case Study From The Middle Eocene-Lower Oligocene Kırkgeçit Formation, Elazığ, Eastern Turkey, Hasan Çeli̇k Jan 2013

The Effects Of Linear Coarse-Grained Slope Channel Bodies On The Orientations Of Fold Developments: A Case Study From The Middle Eocene-Lower Oligocene Kırkgeçit Formation, Elazığ, Eastern Turkey, Hasan Çeli̇k

Turkish Journal of Earth Sciences

A significant magnitude of tectonic feature deflection away from the principal stress direction was investigated. This was caused by oblique spatial orientation of coarse-grained sediment bodies, principally large conglomerate and sand-filled deep-water slope channels, in an otherwise mud-rich sedimentary section. After detailed mapping and field work to find the cause of this localised fold axis deflection, superbly exposed conglomerate and sand filled deep-water slope channel bodies were found both in and/or next to the core of the folds with the same spatial orientation as the folds. It was concluded that the channel bodies are effectively dictating the orientations of the …

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Revisiting The Genesis Of Red Mediterranean Soils, Nicolas Fedoroff, Marie-Agnes Courty Jan 2013

Revisiting The Genesis Of Red Mediterranean Soils, Nicolas Fedoroff, Marie-Agnes Courty

Turkish Journal of Earth Sciences

This work, aside from being a classical discussion on the processes of rubefaction and illuviation, is an attempt to cross the abundant literature on red Mediterranean soils (RMSs) written by pedologists, and also by paleopedologists and geologists, with the climatic frame established by paleoclimatologists for the Quaternary. Such an approach leads us to consider that the development of the RMSs was discontinuous, occurring during periods of environmental stability, i.e. interglacials, characterized by a humid climate (precipitations exceeding evapotranspiration) with dry and hot summers. The impact of glacial intervals on the RMS covers is presently only partially documented. Aeolian processes during …

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The Key Role Of Micromorphology In Studies Of The Genesis Of Clay Minerals And Their Associations In Soils And Its Relevance To Advances In The Philosophy Of Soil Science, Gordon Jock Churchman Jan 2013

The Key Role Of Micromorphology In Studies Of The Genesis Of Clay Minerals And Their Associations In Soils And Its Relevance To Advances In The Philosophy Of Soil Science, Gordon Jock Churchman

Turkish Journal of Earth Sciences

Micromorphological observations from 3 different published works have been studied to aid understanding of aggregation and of colloids, both unique to soils. Saprolites in Hong Kong included ‘veins’ of different thicknesses and colours. Optical mineralogy identified them as infill from the neogenesis of clays in rock fractures. The common thicker infills resulted from weathering. Dark infill contained comminuted primary minerals whereas thin pale infill originated hydrothermally. Scanning electron microscopy (SEM) showed that the size, shape, and mineralogy of the kaolin minerals formed in infill depended on the types of cracks in the saprolites and on drying. Energy-dispersive X-ray spectroscopy analyses …

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Late Holocene Climatic Oscillations Traced By Clay Mineral Assemblages And Other Palaeoceanographic Proxies In Ria De Vigo (Nw Spain), Virginia Martins, Fernando Rocha, Cristina Sequeira, Paula Martins, José Santos, Joao Alveirinho Dias, Olivier Weber, Jean-Marie Jouanneau, Belén Rubio, Daniel Rey, Ana Bernabeu, Eduardo Silva, Lázaro Laut, Rubens Figueira Jan 2013

Late Holocene Climatic Oscillations Traced By Clay Mineral Assemblages And Other Palaeoceanographic Proxies In Ria De Vigo (Nw Spain), Virginia Martins, Fernando Rocha, Cristina Sequeira, Paula Martins, José Santos, Joao Alveirinho Dias, Olivier Weber, Jean-Marie Jouanneau, Belén Rubio, Daniel Rey, Ana Bernabeu, Eduardo Silva, Lázaro Laut, Rubens Figueira

Turkish Journal of Earth Sciences

This work aims to study recent climatic oscillations and their influence on sedimentation in the Ria de Vigo, a coastal embayment in Galicia, NW Spain. It is based on the study of clay mineral assemblages, in conjunction with other proxies (granulometric, geochemical, geochronological and microfaunal), in the core KSGX 24. A Benthic Foraminifera High Productivity (BFHP) proxy was used to determine changes in the flux of organic matter (OM) at the bottom of the study area. Total organic carbon (TOC) content is not a suitable proxy to estimate changes in the past supply of OM due to diagenetic processes. The …

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Clay Mineralogy Of Red Clay Deposits From The Central Carpathian Basin (Hungary): Implications For Plio-Pleistocene Chemical Weathering And Palaeoclimate, János Kovács, Béla Raucsik, Andrea Varga, Gabor Ujvari, György Varga, Franz Ottner Jan 2013

Clay Mineralogy Of Red Clay Deposits From The Central Carpathian Basin (Hungary): Implications For Plio-Pleistocene Chemical Weathering And Palaeoclimate, János Kovács, Béla Raucsik, Andrea Varga, Gabor Ujvari, György Varga, Franz Ottner

Turkish Journal of Earth Sciences

Geochemical and mineralogical studies of palaeosols provide essential information for palaeoclimatic and palaeoenvironmental interpretation of continental deposits and can present a proxy for palaeoclimate. Red clays in the central Carpathian Basin (Hungary) (Tengelic Red Clay Formation; Kerecsend Red Clay Formation), overlain by loess-palaeosol sequences, were studied. Results from geochemical climofunctions applied to Upper Pliocene–Lower Pleistocene red clays and palaeosols located in the Carpathian Basin, and clay mineralogy, indicate that the palaeoclimate was considerably more humid and warmer during the Late Pliocene-Early Pleistocene in comparison to modern values.

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Cover And Contents Jan 2013

Cover And Contents

Turkish Journal of Earth Sciences

No abstract provided.

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Geology Of Late Miocene Clayey Sediments And Distribution Of Palaeosol Clay Minerals In The North-Eastern Part Of The Cappadocian Volcanic Province (Araplı-Erdemli), Central Anatolia, Turkey, Selahatti̇n Kadi̇r, Ali̇ Gürel, Hülya Senem, Taci̇t Külah Jan 2013

Geology Of Late Miocene Clayey Sediments And Distribution Of Palaeosol Clay Minerals In The North-Eastern Part Of The Cappadocian Volcanic Province (Araplı-Erdemli), Central Anatolia, Turkey, Selahatti̇n Kadi̇r, Ali̇ Gürel, Hülya Senem, Taci̇t Külah

Turkish Journal of Earth Sciences

The study area is situated in the Araplı-Erdemli (Kayseri) area in the north-eastern part of the Cappadocian Volcanic Province (CVP), central Anatolia. The Late Miocene series comprises lacustrine and fluvial deposits interbedded with ignimbrites and lava flows. The Late Miocene Mustafapaşa member of the Ürgüp Formation comprises yellow to red mudstone that alternates with thin sandstone beds in the north-eastern part of the CVP. This unit continues upward through the Cemilköy ignimbrite palaeosol layers (comprising altered Cemilköy ignimbrite, vertisol and well-developed palaeosol layers), the Gördeles ignimbrite and red palaeosol layers, and includes two fallout levels; it is overlain by the …

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Multi-Proxy Evidences Of Mid-Pleistocene Dry Climates Observed On Calcretes In Central Turkey, Ceren Küçükuysal, Asuman Günal Türkmenoğlu, Seli̇m Kapur Jan 2013

Multi-Proxy Evidences Of Mid-Pleistocene Dry Climates Observed On Calcretes In Central Turkey, Ceren Küçükuysal, Asuman Günal Türkmenoğlu, Seli̇m Kapur

Turkish Journal of Earth Sciences

Palaeosols are very important in reconstructing palaeoclimate studies, since they are accepted as useful climate markers and as potential providers of proxy data. The study of the palaeosols of the Plio-Pleistocene rock sequences around Ankara revealed evidence for a reconstruction of the Quaternary palaeoclimate of the region. The study area is located in Bala, south-east of Ankara, which contains Middle Pleistocene red palaeosols with powdery to nodular calcrete developments, alternating with channel deposits. During this warm and arid period in the Pleistocene, the limited water available in the soil led to the accumulation of low magnesian carbonates, forming calcretes. The …

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Genesis Of The Hydrothermal Karaçayır Kaolinite Deposit In Miocene Volcanics And Palaeozoic Metamorphic Rocks Of The Uşak-Güre Basin, Western Turkey, Selahatti̇n Kadi̇r, Hülya Erkoyun Jan 2013

Genesis Of The Hydrothermal Karaçayır Kaolinite Deposit In Miocene Volcanics And Palaeozoic Metamorphic Rocks Of The Uşak-Güre Basin, Western Turkey, Selahatti̇n Kadi̇r, Hülya Erkoyun

Turkish Journal of Earth Sciences

The Karaçayır kaolinite deposit, situated in the Uşak-Güre basin of western Turkey, is hosted by rhyolite and andesite of the Miocene Dikendere volcanics, and by muscovite schist, glaucophane schist, talc schist and chlorite schist of the Palaeozoic Eşme Formation. The association of kaolinization with silicification and Fe-oxidation, and the presence of pyrite, chalcopyrite and gypsum, suggest that hydrothermal alteration processes in the volcanics and schists were controlled by faults. Thus, prevalent kaolinite is associated with quartz, smectite, illite and opal-CT in the centre of the deposit, with relative increases in smectite, illite, chlorite and Fe (oxyhydr)oxide phases outwards and upwards. …

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The Geochemistry And Petrology Of The Ophiolitic Rocks From The Kahramanmaraş Region, Southern Turkey, Utku Bağci Jan 2013

The Geochemistry And Petrology Of The Ophiolitic Rocks From The Kahramanmaraş Region, Southern Turkey, Utku Bağci

Turkish Journal of Earth Sciences

The regionally important dismembered ophiolitic sequence from the southern Kahramanmaraş region, located along the Arabian-Eurasian collision zone in southeastern Turkey, contains harzburgitic tectonites, ultramafic to mafic cumulates, isotropic gabbros and ophiolite-related metamorphic rocks. The ultramafic-mafic cumulate rocks are composed of wehrlite, lherzolite, olivine websterite, olivine gabbronorite, olivine gabbro and gabbro. The crystallization order of the cumulus phases, the presence of high Ca-plagioclase (An_{83-94}), highly magnesian clinopyroxene (Mg#_{78-93}), olivine (Mg#_{71-91}) and their coexistence in the ultramafic-mafic cumulate rocks indicate a suprasubduction zone (SSZ) environment and suggest that the cumulates were derived from an island arc tholeiitic (IAT) magma. The isotropic gabbros …

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Colour Origin Of Red Sandstone Beds Within The Hüdai Formation (Early Cambrian), Aydıncık (Mersin), Southern Turkey, Muhsi̇n Eren, Selahatti̇n Kadi̇r Jan 2013

Colour Origin Of Red Sandstone Beds Within The Hüdai Formation (Early Cambrian), Aydıncık (Mersin), Southern Turkey, Muhsi̇n Eren, Selahatti̇n Kadi̇r

Turkish Journal of Earth Sciences

The basal part of the Hüdai Formation (Early Cambrian) in the Aydıncık (Mersin) area comprises red sandstone beds at different stratigraphic levels, showing ripple cross-lamination. These beds were deposited in the middle to lower part of an intertidal flat environment. Bedding-parallel reddening and its cyclic character suggest syn-sedimentary or early diagenetic red colouration in a marine environment. Both X-ray diffraction and petrographic analyses indicate that the red sandstones are composed of predominantly K-feldspar and quartz grains and an illite matrix. These are dominantly arkosic wacke. A small amount of hematite (

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Low-Sulfidation Epithermal Au-Ag Mineralization In The Sındırgı District, Balıkesir Province, Turkey, Hüseyi̇n Yilmaz, Fatma Nuran Sönmez, Erhan Akay, Ahmet Keri̇m Şener, Seda Tufan Jan 2013

Low-Sulfidation Epithermal Au-Ag Mineralization In The Sındırgı District, Balıkesir Province, Turkey, Hüseyi̇n Yilmaz, Fatma Nuran Sönmez, Erhan Akay, Ahmet Keri̇m Şener, Seda Tufan

Turkish Journal of Earth Sciences

The Sındırgı District (Balıkesir, western Turkey) lies within the Western Anatolian volcanic and extensional province, adjacent to the WNW-trending Simav graben, approximately 130 km NE of İzmir. The Sındırgı mining district is underlain mainly by Miocene volcanic rocks and hosts several low-sulfidation epithermal Au-Ag deposits and prospects located near the towns of Sındırgı and Bigadiç. The Kızıltepe low-sulfidation epithermal gold-silver deposit is located southeast of Yusufçam village (Sındırgı, Balıkesir), and other prospects, including the Kepez, Kavaklıdüz, and Karadüz prospects, are located northeast of Kızıltepe. Potentially economic grades occur at Kızıltepe, which contains a measured and indicated resource of 1.754.790 Mt …

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Mineralogical And Physicochemical Properties Of Talc From Emirdağ, Afyonkarahisar, Turkey, Bahri̇ Ersoy, Sedef Di̇kmen, Ahmet Yildiz, Remzi̇ Gören, Ömer Eli̇tok Jan 2013

Mineralogical And Physicochemical Properties Of Talc From Emirdağ, Afyonkarahisar, Turkey, Bahri̇ Ersoy, Sedef Di̇kmen, Ahmet Yildiz, Remzi̇ Gören, Ömer Eli̇tok

Turkish Journal of Earth Sciences

Lens-shaped talc deposits related to Mesozoic gabbroic rocks are exposed in an area of 2 km^2, about 80 km northwest of Afyonkarahisar (western Anatolia). Different alteration zones in talc deposits were determined depending on differences related to the texture and color of the host rock. In order to determine mineralogical, geochemical, and physicochemical features of the Emirdağ talc deposits, X-ray diffractometer, scanning electron microscope (SEM), FT-IR and Mössbauer spectroscopy, differential thermogravimetric analyses, BET-specific surface area, color, water soluble substance, acid-soluble carbonate, and acid-soluble iron tests were performed on the samples collected from different alteration zones in the lateral direction. Four …

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Three-Dimensional Subsurface Modeling Of Mineralization: A Case Study From The Handeresi (Çanakkale, Nw Turkey) Pb-Zn-Cu Deposit, Si̇nan Akiska, İbrahi̇m Sönmez Sayili, Gökhan Demi̇rela Jan 2013

Three-Dimensional Subsurface Modeling Of Mineralization: A Case Study From The Handeresi (Çanakkale, Nw Turkey) Pb-Zn-Cu Deposit, Si̇nan Akiska, İbrahi̇m Sönmez Sayili, Gökhan Demi̇rela

Turkish Journal of Earth Sciences

The main goal of 3D modeling studies in the mining sector is to address the complex geological, mineralogical, and structural factors in subsurface environments and detect the ore zone(s). In order to solve this complexity, use of quality data (e.g., a wide range of boreholes at regular intervals) is necessary. However, this situation is not always possible because of certain restrictions such as intensive vegetation, high slope areas, and some economic constraints. At the same time, with the development of computer technology, the unused and/or insufficiently considered data need to be gathered and reviewed. This assessment may lead to the …

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Geology And Diagenesis Of A Zeolitic Foça Tuff Unit Deposited In A Miocene Phreatomagmatic Lacustrine Environment (Western Anatolia), Mustafa Albayrak, Abdullah Mete Özgüner Jan 2013

Geology And Diagenesis Of A Zeolitic Foça Tuff Unit Deposited In A Miocene Phreatomagmatic Lacustrine Environment (Western Anatolia), Mustafa Albayrak, Abdullah Mete Özgüner

Turkish Journal of Earth Sciences

This study explains the relations between the depositional environment of a zeolitic tuff unit and its diagenesis. It gives new ideas of the juvenile phreatomagmatic origin of the zeolitic unit with its bentonitic cap rock, and finds that the diagenetic alteration of the volcanic ash deposition in a hot hydrologic system is penecontemporaneous and not epigenetic. A massive, fine-grained zeolitic unit has a sharp contact with the underlying shallow subaqueous rhyolitic dome intrusions and their surrounding volcanoclastic ejecta. Juvenile emanations from the basal subaqueous intrusions activated thorough zeolitic diagenesis within the overlying rhyolitic tuff deposits extending as far as the …

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