Geological setting, petrology and geochemistry of metasedimentaries and high-K metavolcanics in the north of Ilgın (Konya), SW Turkey

Ilgın bölgesinde (Konya); Paleozoyik metasedimanterler, bunlar üzerinde uyumsuz Mesozoyik metasedimanterler ve metavolkanikler ve tüm bunları açısal uyumsuzlukla örten Neojen çökeller ve alüvyon yer alır. Çalışma alanının genellikle batı ve orta kesiminde yaygın olarak izlenen Paleozoyik topluluğun kalınlığı 1000 m’ye kadar ulaşır ve çakıltaşı, kumtaşı, silttaşı, kiltaşı, kireçtaşı ve kuvarsitlerin metamorfik türevlerinden oluşur. Mesozoyik topluluk tabanda metakonglomera ile başlayıp üste doğru daha ince taneli ve nihayet karbonatlardan oluşan metasedimanterler ile bunlar arasındaki metalavlar ve metatüflerden oluşmaktadırlar. Mesozoik topluluk içindeki metavolkanik kayalar, yüksek-K’lu riyolitlerin düşük derecede metamorfizmaya uğramış lav ve tüfleridir. Bunların mineral bileşimi; %75-80 matriks (ince taneli kuvars, K-feldspat ve serizit) ile %20-25 oranındaki fenokristallerden (kuvars, K-feldspat,Or94-97, Ab2-6An0-0.74,kalıntı sanidin ve albit) oluşur. Matrikste serizitleşme, feldspatlaşma ve silisleşme belirgindir, birincil doku ayırt edilebilmektedir. Yüksek-K’ lu metavolkanikler (K2O: % 7-11) kalkalkali karakterlidirler. Nadir toprak element dağılımı; (La/Lu)N: 0.87-215.54 ve (Eu/Eu*)N: 0.0024-0.23 aralığını (negatif Eu anomalisi) verir. Paleozoik metamorfik grupta kloritoid ve stilpnomelanın varlığı ve Mesozoik metamorfik grupta bu minerallerin olmayışı metamorfizma derecesinin alttan üste doğru azaldığını gösterir. Muskovit K-Ar değerlerine göre (Paleozoyik metamorfik grup örneği: 96.9±1.4My, Mesozoyik metamorfik grup örnekleri; 70.2±1.0My, 65.6±1.0My ve 64.4±1.0My) bölge çok evreli metamorfizmanın etkisinde kalmış ve metamorfizmanın son evresi Üst Kretase-Alt Paleosen’de gelişmiştir. Metavolkanik tüm kaya K-Ar değerleri 60.4±0.9My, 62.6±0.9My ve 64.1±2.0My olarak elde edilmiştir. Anahtar Kelimeler: Afyon-Bolkardağ Zonu, jeokronoloji, yüksek-K metavolkanikler, Ilgın-Konya, metamorfizma, Turkey.The Afyon-Bolkardağ Zone is one of the metamorphic belts, along with the Tavşanlı Zone, Menderes Massif and Lycian Nappes in western Anatolia, eastern Mediterranea. The study area included by thiz zone is located in the north of Ilgın (Konya-Turkey). Two main metamorphic groups and cover series unconformably overlaid each other from Ilgın of Konya province are reported in this study. From bottom to top, these are: Paleozoic metasedimentary group, Mesozoic metasedimantary and metavolcanic group, Neogene covers and Quaternary alluvium. The Paleozoic group is 1000m in thickness observed particularly in the west and middle part of the study area. This group is derived from the metamorphics of conglomerate, sandstone, siltstone, claystone, limestone and quartzite. Metaconglomerates consist of chert, shale, quartz and green schist fragments in clayey-sandy matrix. Metasandstones are grayish color, grain-supported, well-consolidated and carbonate cemented and bedding is from fine to medium. Phyllites are made up of mainly thin mica flakes and rarely fine-grained quartz and feldspar. Metacherts are thin-bedded, gray in color. Metacarbonates include elongated, flatted calcites, muscovite, chlorite, tourmaline and quartz. Metaconglomerates, at the base of Mesozoic group, purple-pinkish in color pass gradually laterally and vertically into metasandstones. Metasandstones are grayish-reddish-greenish color, mostly 5-30 cm and rarely 10 m in thickness. Metacarbonates are generally dolomitic limestone and dolomite and gray, white and yellow in color. They are in upper levels of Mesozoic group. In this study, we stated that rhyolitic metavolcanics are different from others formerly cited in Ilgın (Konya). These rocks are light-dark gray and green colors. These are mostly metalavas and metatuffs unmapped in scale and thin bedded within schists. The black white alteration surfaces are widespread in the rocks considered lava origin. The foliation is marked in the passing into the schists and muscovites are wieved along foliation plains. The Paleozoic metasandstone and schist samples have high content of SiO2. Na2O values of Paleozoic samples vary from zero to 2.15 % and a higher value of K2O (5.8 %) is found in some samples. The values of high Rb and low Sr in some samples are significant. Schists have 64.2-81.33% SiO2. These values suggest that the Paleozoic group is felsic lithologies and acidic in character. Ba values are in the range of 6-485 ppm. On the other hand, some samples have high Zr values (486 ppm). The high contents of Rb may have resulted from the presence of muscovite in these rocks. Na2O and K2O values are very low whereas Sr values are high in dolomitic metacarbonates. Magma composition changes due to mineral fractionations. K2O, CaO, MgO, Fe2O3 and TiO2 show negative correlations with increasing SiO2 whereas Na2O shows positive correlation. As the SiO2 content increases, the Sr, Ba, Co, Th, Sc and Hf contents decrease and the Rb content increases. However, Cs shows variation. Linear correlations can be explained by fractional crystallizations whereas such unlinear trends as negative and/or positive correlations can be explained by partial alterations and magma mixing in major and trace element diagram. Metavolcanics have 75-80% groundmass and 20-25% phenocrysts. Phenocrysts are quartz, K-feldspar, remnant sanidine and albite. Feldspars occur mostly as K-feldspar (Or 85-97 Ab 3-6 An 0-2). Matrix is composed of microcrystalline quartz, K-feldspar, sericite and rarely muscovite. The metavolcanics have 66-77% SiO2, 5.8-10.6% K2O, 0.08-1.77% Na2O, 12-18% Al2O3, 0.1-0.4% MgO, <1% CaO. This chemical composition suggests that metavolcanics are high-K rocks with acidic character. The Ba contents of some samples reach up to the high levels. Plotting data for metavolcanics in the SiO2 vs. Zr/TiO2 diagram samples fall into the rhyolite field. Metavolcanics are extremely K-rich (7-11 wt. % K2O), calc-alkaline in character and show also strong enrichment in LILE and LREE. Metavolcanics show concave REE pattern with (La/Lu)N:0.87-215.54 and have negative Eu anomalies (Eu/Eu*)N:0.0024-0.23. One sample, 3.92, from Paleozoic unit in Ilgın (Konya) region, yielded muscovite age of 96.9±1.4 Ma, whilst three samples, 4.10, 3.109 and TSD1, yielded muscovite ages of 70.2±1.0Ma, 65.6±1.0Ma and 64.4±1.0Ma, implying polyphase metamorphism in this region and the last phase was in Upper Cretaceous-Lower Paleocene. Three samples, 3.37, 3.122 and 2.5 from metavolcanics yielded whole rock ages of 60.4±0.9Ma, 62.6±0.9Ma and 64±2.0Ma.  Keywords: Afyon-Bolkardağ Zone, geochemistry, geochronology, high-K metavolcanics, Ilgın-Konya, metamorphism

Geology of Neogene sediments in Turgutlu (Manisa) Region

Çalışma alanı (Turgutlu/Manisa) Batı Anadolu’nun merkezi bölümünde, Gediz Grabeni içerisinde yer almaktadır. Bölgedeki temel kaya birimleri; Menderes Masifi ve İzmir-Ankara zonuna ait kayaçlardır. Gediz grabeni asimetrik bir graben olduğu için, Turgutlu havzasının kuzey ve güney bölümlerinde yer alan Neojen yaşlı çökeller farklılık gösterirler. Çalışma alanında Alt-Orta Miyosen devresi Turgutlu formasyonu ile temsil edilir. Pliyosen devresi çalışma alanının kuzey kesiminde Kanlıtepe formasyonu güney bölümünde ise Halilbeyli formasyonu tarafından temsil edilir. Çalışma alanının en genç Neojen çökellerini ise güney bölümde görülen fluviyal kaba kırıntılılardan oluşan Pliyosen-Pleyistosen yaşlı Kupyartepe formasyonu oluşturmaktadır. Normal faylar çalışma alanındaki çökel istifin konumunu büyük ölçüde denetlemişlerdir.Anahtar Kelimeler: Gediz grabeni, Turgutlu, Neojen çökelleri. The study area (Turgutlu/Manisa) is  located in the Gediz Graben which is the central part of western Anatolia. Gediz Graben is a basin of the east-west trending, in an arc shaped form and with a length of 140 km. The basement rock units of the region are Menderes Massif  and İzmir-Ankara Zone ophiolitic rock complex. Neogene deposites in northern and southern parts of the Turgutlu basin are different from each other due to the asymmetric characteristics of Gediz Graben. In the study area early-middle Miocene period is represented by Turgutlu formation made of mainly conglomerates, sandstones, claystones. Pliocene period is represented by Kanlıtepe formation in the northern part of the study area and by fluvial Halilbeyli formation made of coarse grained clastics in the southern part of the study area. The youngest Neogene sediments of the study area constitute Pliocene-Pleistocene aged Kupyartepe formation made of fluvial coarse grained clastics presented in the southern parts of the study area. The strikes of the faults in the study area are generally E-W and NE-SW and the dips of the faults are about 50-65o. The slips of the faults measured are generally between 2 and 6 meters. These fault systems are cut with NW strike antitethic faults. Keywords: Gediz Graben, Turgutlu, Neogene sediments

TEKİRDAĞ BÖLGESİ (TRAKYA) ALKALİ BAZALTLARI İÇERİSİNDEKİ PERlDOTİTİK KSENOLİTLER

Tekirdağ bölgesindeki (Trakya) bazaltik volkanitler içerisinde üst mantonun birer parçası olarak düşünülen harzburjit ve dunit türü peridotit ksenolitler saptanmıştır. Bazaltik lavlar petrografik olarak başlıca plajiyoklaz, olivin, ojit, manyetit ve nadir hipersten bileşimli birincil parajeneze ve lokal olarak önemli oranlarda olabilen ikincil minerallere sahip olivinli bazaltlardır. Jeokimyasal açıdan ise alkali bazalt, trakibazalt ve bazanit kaya türlerine karşılık gelirler, içerisinde peridotit ksenolit saptanmış Hacıköy ve Balabanlı bazalt örnekleri ile peridotit ksenolitlerin bulunmadığı Muratlı bazalt örnekleri arasında ana ve iz element içerikleri açısından da farklılıklar vardır. Olivin (forsterit), enstatit, Cr-spinel ve nadir diyopsit bileşimli peridotit ksenolitler tipik olarak protogranüler, kısmen geçişli olarak porfiroklastik dokulu olup, magmatik dokuları büyük ölçüde korunmuştur. Foliasyon ve lineasyon göstermezler, iri ve çok iri taneli, kavisli tane sınırlıdırlar. Mekanik etkiyi işaret eden, ikizlenme benzeri, bandlanmalar ve deformasyon lamelleri olivin ve piroksenlerdeki özelliklerdir. Peridotit ksenolitlerin ana elemanları arasında orijinal mantonun kısmî ergimesini ifade eden ilişkiler bulunur. Ancak, ergime derecesi muhtemelen düşüktür. Metasomatizmadan etkilenmemişlerdir ve primitif mantoya göre bir miktar tüketilmiş bileşim gösterirler

The separation efficiency of Na-bentonite by hydrocyclone and characterization of hydrocyclone products

Upgrading of bentonites in sodium or mixed forms through wet separation methods is considered because such low solid suspensions require filtration followed by drying. These wet separation methods turn into effective and compatible processes for high selling prices such as water and solvent based bentonites. In this study, Na-bentonites were subjected to a series of multistage hydrocyclone testing to evaluate the separation efficiencies related to the hydrocyclone parameters such as vortex and apex diameters and feed pressures. In each hydrocyclone test, the run of mine bentonite was split into different fractions of various qualities. The separation efficiencies and the corresponding products were examined and characterized based on some technological properties such as cation exchange capacity, viscosity, swelling ability along with particle sizes, and chemical and mineralogical analyses. It is shown that for clay minerals such as smectites and also bentonite minerals, cation exchange capacity is the best method for assaying the concentration products and for evaluating the metallurgical balance though other characteristic properties such as chemical analysis, swelling, gelling and viscosity could be used as complementary. (C) 2010 Elsevier B.V. All rights reserved

THE CHARACTERIZATION OF MEDIEVAL CERAMICS EXCAVATED FROM THE EĞIRDIR CARAVANSERAI (TURKEY)

Thirteen potsherds from the Eğirdir Caravanserai (south-west of Turkey) were characterized by optical microscopy (OM), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Mineralogical and petrographic studies of medieval potsherds in there show a ceramic body composed of a microcrystalline to amorphous matrix with various clasts and voids. The thin section, XRD and SEM analyses of samples showed that potsherds consist of K-feldspar (orthoclase), plagioclase (albite and anorthite), pyroxene (diopside), melilite (gehlenite), mullite, wollastonite, mica (biotite and muscovite), chlorite, leucite, amphibole, quartz, calcite, iron minerals (hematite and magnetite) and trace amounts of sphene. The obtained results showed that calcareous materials including illitic-kaolinitic clays were used for pottery production and the potsherds were fired in the temperatures from 800 to 1150°C

Petrogenesis of Miocene volcanism in the Central Anatolia: Geochemical, isotopic and geochronological evidence

This paper presents the first 40Ar/39Ar age data, new bulk-rock major-trace element compositions and Ndsingle bondSr isotope geochemistry, combined with detailed geological mapping of Galatia Volcanic Province (GVP) in the northwest Central Anatolia (Turkey). Here, there are voluminous extrusive rocks in a wide compositional range: a basalt, andesite and trachyte suite, and their pyroclastic equivalents. 40Ar/39Ar dating of two whole-rock samples from the GVP yielded plateau ages of 21.76 ± 0.8 Ma and 20.97 ± 0.5 Ma, constrain the volcanic activity at ca. 21 Ma (Aquitanian). The samples show by sub-parallel light rare earth element (LREE)-enrichment and relatively flat heavy rare earth element (HREE) patterns and moderate fractionation [average (La/Yb)N = 13.5]. Their initial 87/86Sr values vary between 0.704619 and 0.704998, while initial 143/144Nd values lie between 0.512673 and 0.512755. Integration of the geochemical and geochronological with geological data we propose that the volcanic rocks in the northern area of GVP with calc-alkaline affinity were produced by a lithospheric mantle magma in an extensional setting