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Öğe Abatement of nitrous oxide over natural and iron modified natural zeolites(ELSEVIER SCIENCE BV, 2011) Ates, Ayten; Reitzmann, Andreas; Hardacre, Christopher; Yalcin, HuseyinThe natural zeolite obtained from the Sivas-Yavu region in Turkey and iron modified forms were studied for the decomposition of N(2)O and selective catalytic reduction of N(2)O with NH(3). The natural and iron modified zeolites were characterised by XRD, SEM, H(2)-TPR, NH(3)-TPD and low temperature nitrogen sorption. The effect iron loading, precursor and valency on the catalytic performance of catalysts were studied. The catalytic activity of the zeolites increased up to about 7.0 wt.% Fe. Above this value, the activity decreased as a result of a reduction in the surface area and pore volume of the zeolite. The highest catalytic activity was observed using catalysts prepared with FeCl(2) due to the formation of more reducible iron species in the zeolites. When FeSO(4) was used as the iron precursor, sulphate remained on the surface even after extensive washing resulting in a decrease in the N(2)O decomposition activity and a shift the N(2)O reduction temperature to higher values. Since the natural and iron exchanged natural zeolites prepared using FeCl(2) have comparable activity with synthetic zeolites, the offer a promising alternative catalyst for the abatement of N(2)O, particularly for the selective reduction of N(2)O with NH(3). (C) 2011 Elsevier B.V. All rights reserved.Öğe Alteration Mineralogy and Geochemistry of the rocks from Tekirova (Antalya) Ophiolite Nappe(TMMOB JEOLOJI MUHENDISLERI ODASI, 2015) Yalcin, Huseyin; Bozkaya, Omer; Yilmaz, CananThe Tekirova Ophiolite Nappe, part of the Antalya Unit in the southwest Anatolia, consists of a dismembered oceanic crust sequence with tectonic slices in different sizes. Three types of subsequent mineralizations are present in the ophiolitic rocks during the oceanic crust formation, emplacement and post-emplacement, respectively. First stage, pyrometamorphism (pyrometasomatization) caused to occurrence of metamorphic minerals such as scapolite, diopside, garnet, epidote and tremolite. Second stage, hydrothermal metamorphism(alteration) is represented byserpentinization of ultramafic rocks. Third stage is followed by listwaenite formation, and age neoformation and/or alteration products contain carbonates (calcite, dolomite, aragonite, magnesite, hydromagnesite, hydrotalcite), oxides and hydroxides (brucite, goethite, hematite), phyllosilicates (smectite, illite, chlorite, talc, C-V, C-S, I-S) and quartz. The serpentine minerals can be distinguished from each other by morphology: ribbon-like shapes for antigorite, platy for lizardite and fibrous for chrysotile. Serpentines are represented by three polytypes as structural groups of A- (clinochrysotile-2M(1)), C- (lizardite-1T) and D- (lizardite-2H(1)). Chondrite-normalized trace and rare earth element patterns of 1T and 2H(1) Fe-lizardites, Fe-tremolite and Ca-hydromagnesite minerals show similar trends indicating similar ophioliticparent rocks and differentiated form each others. The delta O-18 and delta D values of serpentines indicate two different serpantinization under hypogene conditions as oceanic (lizardite-1T) and supergene as Alpin types (clinochrysotile-2M(1) and lizardite-2H(1)) at temperatures of about 200 degrees C and 100 degrees C, respectively.Öğe Approaches to the Low Grade Metamorphic History of the Karakaya Complex by Chlorite Mineralogy and Geochemistry(MDPI AG, 2015) Tetiker, Sema; Yalcin, Huseyin; Bozkaya, OmerIn this study, chlorite is used to investigate the diagenetic-metamorphic evolution and accurate geological history of the different units belonging to the Karakaya complex, Turkey. Primary and secondary chlorite minerals in the very low-grade metamorphic rocks display interference colors of blue and brown and an appearance of optical isotropy. Chlorites are present in the matrix, pores, and/or rocks units as platy/flaky and partly radial forms. X-ray diffraction (XRD) data indicate that Mg-Fe chlorites with entirely IIb polytype (trioctahedral) exhibit a variety of compositions, such as brunsvigite-diabantite-chamosite. The major element contents and structural formulas of chlorite also suggest these were derived from both felsic and metabasic source rocks. Trace and rare earth element (REE) concentrations of chlorites increase with increasing grade of metamorphism, and these geochemical changes can be related to the tectonic structures, formational mechanics, and environments present during their generation.Öğe Approaches to the Low-Grade Metamorphic History of the Karakaya Complex by Chlorite Mineralogy and Geochemistry(TMMOB JEOLOJI MUHENDISLERI ODASI, 2015) Tetiker, Sema; Yalcin, Huseyin; Bozkaya, OmerChlorite minerals are commonly found in the units of Karakaya Complex that reflect different tectonic settings and evolution. In this study, the availability of chlorites has been investigated as a parameter on the interpretation of the diagenetic-metamorphic evolution and revealing the geological history from the different units of the complex. Primary and secondary chlorite minerals in the low-very low-grade metamorphic rocks have interference colors of blue and brown and an optical isotropic appearance with very low birefringence. Chlorites are seen in the matrix, pores and/or pods of rocks as platy/flaky and partly radial forms. According to X-ray diffraction (XRD) data; Mg-Fe chlorites with entirely IIb polytype (trioctahedral) exhibit various compositions such as brunsvigite-diabantite-chamosite. Furthermore, chlorite minerals correspond to felsic and metabasic origins in terms of the rocks from which they derived. Similarly, geochemical data such as the major element contents and structural formulas of chlorites also suggest a different composition and origin. Trace and especially rare earth element (REE) concentrations of chlorite minerals increase from schist towards slate depending on their degree of metamorphism and nature of the host rocks. This relationship can be significantly noticed in the chondrite-normalized REE and trace element patterns. These changes show that are they are related to the structures, formation mechanisms and tectonic environments of the chlorite minerals. In other words, they suggest that chlorites may play a key role in distinguishing of units with different geological history.Öğe The assessment of the malignant mesothelioma cases and environmental asbestos exposure in Sivas province, Turkey(SPRINGER, 2014) Berk, Serdar; Yalcin, Huseyin; Dogan, Omer Tamer; Epozturk, Kursat; Akkurt, Ibrahim; Seyfikli, ZehraOne of the most significant diseases related to environmental asbestos exposure is malignant mesothelioma (MM). Sivas province is located in the Central Anatolia where asbestos exposure is common. We aimed to study clinical, demographical and epidemiologic features of the patients with MM in Sivas, along with the history of asbestos exposure. In total, 219 patients with MM who were diagnosed in our hospital between 1993 and 2010 were retrospectively analyzed in terms of demographical and clinical features. Rock, soil and house plaster samples were taken from the habitats of those patients and were evaluated with optical microscopy and X-ray diffraction methods. The age of the patients ranged between 18 and 85 years. The male-to-female ratio was 1.4:1. Most of the patients confirmed an asbestos exposure history. The most frequent symptoms of the patients were chest pain (60 %) and dyspnea (50 %). The gap between the start of first symptoms and the diagnosis date was approximately 4 months in average. The plaster materials used in most of the houses were made up of mainly carbonate and silicate minerals and some chrysotile. Ophiolitic units contained fibrous minerals such as serpentine (clino + orthochrysotile) chiefly and pectolite, brucite, hydrotalcite and tremolite/actinolite in smaller amounts. MM is not primarily related to occupational asbestos exposure in our region, and hence, environmental asbestos exposure may be indicted. Yet, single or combined roles and/or interactions of other fibrous and non-fibrous minerals in the etiology of MM are not yet fully understood and remain to be investigated.Öğe Clay mineralogy of the Paleozoic-Lower Mesozoic sedimentary sequence from the northern part of the Arabian Platform, Hazro (Diyarbakir, Southeast Anatolia)(SLOVAK ACAD SCIENCES GEOLOGICAL INST, 2011) Bozkaya, Omer; Yalcin, Huseyin; Kozlu, HuseyinThe Paleozoic-Lower Mesozoic units in the Diyarbakir-Hazro region consist of sandstone (subarkose, quartz arenite), mudstone, shale, coal, marl, dolomitic marl, limestone (biomicrite, lithobiosparite, biosparite with lithoclast, dololithobiosparite, dolomitic cherty sparite) and dolomite (dolosparite, dolosparite with lithoclast, biodolosparite with glauconite). These units exhibit no slaty cleavage although they are oriented parallel to bedding planes. The sedimentary rocks contain mainly calcite, dolomite, quartz, feldspar, goethite and phyllosilicates (kaolinite, illite-smectite (I-S), illite and glauconite) associated with small amounts of gypsum, jarosite, hematite and gibbsite. The amounts of quartz and feldspar in the Silurian-Devonian units and of dolomite in the Permian-Triassic units increase. Kaolinite is more commonly observed in the Silurian-Devonian and Permian units, whereas illite and 1-S are found mostly in the Middle Devonian and Triassic units. Vertical distributions of clay minerals depend on lithological differences rather than diagenetic/metamorphic grade. Authigenetic kaolinites as pseudo-hexagonal bouquets and glauconite and I-S as fine-grained flakes or filaments are more abundantly present in the levels of elastic and carbonate rocks. Illite quantities in R3 and RI 1-S vary between 80 and 95 %. 2M(1)+1M(d) illites/1-S are characterized by moderate h cell values (9.005-9.040, mean 9.020 angstrom), whereas glauconites have higher values in the range of 9.054-9.072, mean 9.066 angstrom. KI values of illites (0.72-1.56, mean 1.03 Delta 2 theta degrees) show no an important vertical difference. Inorganic (mineral assemblages, KI, polytype) and organic maturation (vitrinite reflection) parameters in the Paleozoic-Triassic units agree with each others in majority that show high-grade diagenesis and catagenesis (light petroleum-wet gas hydrocarbon zone), respectively. The Paleozoic-Triassic sequence in this region was deposited in the environment of a passive continental margin and entirely resembles the Eastern Taurus Para-Autochthon Unit (Geyikdagi Unit) in respect of lithology and diagenetic grade.Öğe Diagenesis/Metamorphism History of Lower Triassic Cigli Group Rocks in Uludere-Uzungecit (Sirnak) area (Eastern Part of the Southeast Anatolian Autochthone)(TMMOB JEOLOJI MUHENDISLERI ODASI, 2016) Tetiker, Sema; Yalcin, Huseyin; Bozkaya, OmerThis study aims to reveal the mineralogical characteristics of the carbonate and pelitic rocks in the Lower Triassic Cigli Group in the Uludere-Uzungecit (Sirnak) region from Southeast Anatolian Autochthone (SEAA). Cigli Group is represented by Yoncali Formation (dolomite-siltstone-shale with limestone intercalation), Uludere Formation (shale/shale with carbonate-clayey limestone intercalated with dolomite) and Uzungecit Formation (limestone with chert nodule-dolomitic limestone-shale) from bottom to top. In order of abundances of minerals obtained by XRD investigations as follows; Yoncali Formation contains carbonate (calcite, dolomite), feldspar, phyllosilicate (illite, chlorite) and goethite minerals, and Uludere Formation is made up of carbonate (calcite, dolomite), quartz, feldspar, phyllosilicate (illite, chlorite, mixed-layered chlorite-vermiculite/C-V, and very minor amount of kaolinite in only a sample) and hematite minerals. Uzungecit Formation has carbonate (dolomite, calcite), silica (quartz, opal-CT, moganite), phyllosilicate (chlorite, illite), and feldspar and hematite minerals. On the basis of illit Kubler Index values; Yoncali Formation reflects the degrees of anchizone; as for Uludere and Uzungecit formations, they have the degrees of anchizone-high diagenesis, respectively. Similarly, Chlorite Arkai Index (AI, degrees 2 theta) values indicate the grades of anchizone-diagenesis. Illites exhibit 2M(1) ve 2M(1) + 1M + 1M(d) polytypes and the values of b unit-cell distances show a composition close to ideal muscovite and low pressure conditions. The rocks of the Cigli Group offer differences in terms of rare occurrence of kaolinite, appearance of moganite and C-V and the dominance of dolomite and hematite in most levels, and diagenesis/metamorphism grades are also high, when compared with the equivalent units in the Diyarbakir-Hazro area. Lower Triassic series regionally seem to have a deeper depositional environment, and have relatively higher maturation because of the volcanic feeding and tectonic burial in the Diyarbakir-Sirnak direction from west to east.Öğe Diagenetic and very low-grade metamorphic characteristics of the Paleozoic series of the Istanbul Terrane (NW Turkey)(SPRINGER BASEL AG, 2012) Bozkaya, Omer; Yalcin, Huseyin; Goncuoglu, Mehmet CemalThe Istanbul Terrane along the Black Sea coast in NW Anatolia, is a Gondwana-derived continental microplate, comprising a well-developed Paleozoic succession. Petrographic and X-ray diffraction studies were performed on rock samples from measured sections throughout Ordovician-Carboniferous sedimentary units. Diagenetic-very low-grade metamorphic clastic (shale/mudstone, siltstone, sandstone) and calcareous rocks (limestone, dolomite) mainly contain phyllosilicates, quartz, feldspar, calcite, dolomite, hematite and goethite minerals. Phyllosilicates are primarily represented by illite, chlorite, mixed-layered chlorite-vermiculite (C-V), chlorite-smectite (C-S) and illite-chlorite (I-C). Feldspar is commonly present in the Ordovician and Carboniferous units, whereas calcite and dolomite are abundant in the Silurian and Devonian sediments. The most important phyllosilicate assemblage is illite + chlorite + I-C + C-V + C-S. Illite and chlorite-bearing mixed layer clays are found in all units. The amounts of illites increase in the upper parts of the Silurian series and the lower parts of the Devonian series, whereas chlorite and chlorite-bearing mixed-layers are dominant in the Ordovician and Carboniferous units. Kubler index values of illites reflect high-grade anchimetamorphism for the Early Ordovician rocks, low-grade metamorphism to high-grade diagenesis for the Middle Ordovician-Early Silurian rocks and high-grade diagenesis for the Late Silurian-Devonian units. The K-white micas b cell dimensions indicate intermediate pressure conditions in the Early Ordovician-Early Silurian units, but lower pressure conditions in the Middle Silurian-Devonian units. Illites are composed of 2M(1) +/- 1M(d) polytypes in all units, except for Upper Ordovician-Lower Silurian units which involve 1M polytype in addition to 2M(1) and 1M(d) polytypes. The 2M(1)/(2M(1) + 1M(d)) ratios rise from Devonian to Ordovician together with the increasing diagenetic-metamorphic grade. Chlorites have IIb polytype. In general, crystal-chemical data of clay minerals in the Istanbul Terrane show a gradual increase in the diagenetic/metamorphic grade together with increasing depth. The new data presented in this work indicate that the diagenetic/metamorphic grade of the Paleozoic of the Istanbul Terrane is higher than that of the neighboring Zonguldak Terrane and generated by a single metamorphic phase developed at the end of Carboniferous. This finding contrasts with the metamorphic history of the neighboring Zonguldak Terrane that displays a distinct Early Devonian unconformity and a thermal event.Öğe Dietary effects of Ca-zeolite supplementation on some blood and tibial bone characteristics of broilers(SOUTH AFRICAN JOURNAL OF ANIMAL SCIENCES, 2011) Eleroglu, Hasan; Yalcin, Huseyin; Yildirim, ArdaThis study was conducted to investigate the effects of differing amounts of natural Ca-zeolite on bone and some blood parameters. A total of 240 day-old Ross 308 broiler chicks were assigned to four treatments with three replicates, each containing 20 day-old chicks of mixed sex. A clinoptilolite+mordenite type of zeolite was added in the broiler diets at levels of 0 g/kg, 10 g/kg, 30 g/kg, and 50 g/kg. Stocking density was 14 broilers/m(2). During the six-week trial, blood parameters and bone characteristics were monitored. The inclusion of Ca-zeolite, at various levels, did not have any significant effect on the concentration of blood serum biochemical parameters; serum glucose, cholesterol, total protein, uric acid; concentrations of Ca, P, Na, K, Cl, and on tibial bone characteristics (tibia weight, ash, volume, specific gravity, and Ca and P contents) in the two sexes and mixed-sex between the groups at 21 and 42 days of age.Öğe The evaluation of the relationship between malignant mesothelioma and environmental asbestos exposure in Sivas(EUROPEAN RESPIRATORY SOC JOURNALS LTD, 2012) Berk, Serdar; Yalcin, Huseyin; Epozturk, Kursat; Dogan, Omer Tamer; Seyfikli, Zehra; Akkurt, Ibrahim…Öğe Evidence of the diagenetic history of sediment composition in Precambrian-early Paleozoic rocks: a systematic study from the Southeast Anatolian Autochthon, Mardin (Derik-KA +/- zA +/- ltepe), Turkey(SPRINGER HEIDELBERG, 2015) Tetiker, Sema; Yalcin, Huseyin; Bozkaya, OmerThe mineralogical properties of the Precambrian-early Paleozoic series have been investigated in the Southeast Anatolian Autochthon (SEAA) and are represented by generally clayey siliciclastic and rarer volcanogenic rocks. These include basalt, andesite, and volcanic sandstones of the Precambrian period; siliceous sandstone, dolomite, shale, and siltstone of the Cambrian period; and sandy dolomite, shale, siltstone, sandstone, and limestone with red Fe nodules of the Lower-Upper Ordovician period. The rock-forming minerals determined in order of abundance are feldspar, pyroxene, quartz, and olivine in the Precambrian unit; quartz, moganite, calcite, dolomite, feldspar, and phyllosilicates (illite, chlorite, mixed-layered illite-smectite/I-S, smectite) in the Cambrian units; and phyllosilicates (kaolinite, illite, chlorite, I-S, mixed-layered chlorite-vermiculite/C-V, smectite), quartz, feldspar, calcite, dolomite, moganite, and goethite in the Lower-Upper Ordovician units. Short prismatic and partly radiating moganites discovered in the early Paleozoic sediments in Turkey are present between euhedral and coarse-grained quartz and feldspar in the sandstones. Thin platy illites have undergone a transition that introduces a fibrous/thread-like mixed-layer I-S through their edges. The rhombohedral dolomites have dissolution traces associated with siliceous balls, long thin filament-shaped illites, and acicular-radial chlorites. Illites usually show coarse and tiny plates parallel to each other and partly radiating flakes, and chamosite-type chlorites form thick plates in the siliciclastics. Kaolinites consist of typical pseudohexagonal sheets with parallel or accordion-like booklets in the siltstones. The Kubler index indicates low- to high-grade diagenesis to low-grade diagenesis, signifying that the location partially differs from the other units of the SEAA and Taurus Belt. In addition, Paleozoic rocks reflect no maturation characteristics with respect to the petroleum system.Öğe Geochemical Properties of Phyllosilicates in Goksun, Afsin and Ekinozu Metamorphites (Kahramanmaras, Turkey)(Tmmob Jeoloji Muhendisleri Odasi, 2021) Hozatlioglu, Deniz; Bozkaya, Omer; Yalcin, HuseyinThis study determined the geochemical properties of phyllosilicates in the Upper Palaeozoic-Lower Mesozoic metamorphic units outcropping from west to east in the vicinities of Goksun, Afsin and Ekinozu towns in the north of Kahramanmaras province in the westerly part of the Eastern Taurus mountains. Geochemical examination of phyllosilicates (major and trace elements, stable isotope) was carried out on pure K-micas and illite/K-micas separated from low-medium grade metamorphic samples. According to the main oxide composition of the phyllosilicates, illite/K-micas from the areas of Afsin and Goksun contain higher SiO2 and Al2O3 and lower MgO, Fe2O3, MnO and Na2O compared to those in the area of Ekinozu. The minerals represented by schists in the Ekinozu K-micas are close to having a biotite-celadonite composition while those with phyllites in Afsin and Ekinozu are close to muscovite composition. Chlorites have a trioctahedral composition between chamosite and clinochlor. Illite/K-micas with both trioctahedral and dioctahedral characteristics show a composition between muscovite and biotite (biotite-celadonite, muscovite-phlogopite, muscovite-ferriphengite, muscovite-ferrobiotite, Al-phlogopite-Alannite) in general. In the trace element content of phyllosilicate minerals, transition metals and granitoid elements are at high concentrations while other elements, especially elements with low (LFSE) and high field strength (HFSE), display low concentrations. In the chondrite-normalized trace element content of phyllosilicate minerals, chlorites have higher values compared to K-micas and trioctahedral K-micas show lower values compared to dioctahedral K-micas. Rare earth element (REE) distribution of chlorite and sericite/K-mica minerals is normalised to chondrite and North American Shale Composition (NASC); the dioctahedral K-mica of Afsin region has the highest depletion, while the trioctahedral mica of Ekinozu has the highest enrichment. The oxygen and hydrogen isotope composition of the phyllosilicate minerals show that they are in the hypogene region, which represents high temperature and deep environment conditions. The oxygen and hydrogen isotope values of sericite/K-mica and chlorites indicate that the formation temperatures of these minerals varied between 375 and 500 degrees C. 40Ar/39Ar radiometric age data for the metamorphic rocks show that the metamorphism developed during the Upper Cretaceous (Santonian-Campanian) in the Afsin and Goksun regions and the Lower-Middle Eocene (Ypresian-Bartonian) periods in the Ekinozu region.Öğe GEOCHEMISTRY OF MIXED-LAYER ILLITE-SMECTITES FROM AN EXTENSIONAL BASIN, ANTALYA UNIT, SOUTHWESTERN TURKEY(CLAY MINERALS SOC, 2010) Bozkaya, Omer; Yalcin, HuseyinThe Antalya Unit, one of the allochthonous units of the Tauride belt, is of critical, regional tectonic importance because of the presence of rifling remnants related to the break-up of the northern margin of Gondwana during Triassic time. Paleozoic-Mesozoic sedimentary rocks of the Antalya Unit consist mainly of calcite, dolomite, quartz, feldspar, and phyllosilicate (illite-smectite, smectite, kaolinite, chlorite, illite, chlorite-smectite, and chlorite-vermiculite) minerals. Illite-smectite (I-S) was found in all of the sequences from Cambrian to Cretaceous, but smectite was only identified in Late Triassic-Cretaceous sediments. R0 I-S occurs exclusively in early-diagenetic Triassic-Cretaceous units of the Alakircay Nappe (rift sediments), whereas R3 I-S is present in late-diagenetic to low-anchimetamorphic Cambrian-Early Triassic units of the Tahtalidag Nappe (pre-rift sediments). Kubler Index (KI) values and the illite content of I-S reflect increasing diagenetic grades along with increasing depth. Major-element, trace-element, rare-earth-element (REE), and stable-isotope (O and H) compositions were investigated in dioctahedral and trioctahedral smectites and I-S samples from the pre-rift and rift-related formations. Both total layer charge and interlayer K increase, whereas tetrahedral Si and interlayer Ca decrease from smectite to R3 I-S. Trace-element and REE concentrations of the I-S are greater in pre-rift sediments than in rift sediments, except for P, Eu, Ni, Cu, Zn, and Bi. On the basis of North American Shale Composite (NASC)-normalized values, the REE patterns of I-S in the pre-rift and rift sediments are clearly separate and distinct. Oxygen (delta O-18) and hydrogen (delta D) values relative to SMOW (Standard Mean Oceanic Water) of smectite and I-S reflect supergene conditions, with decreasing delta O-18 but increasing delta D values with increasing diagenetic grade. Lower delta D values for these I-S samples are characteristic of rift sediments, and pre-rift sediments have greater values. On the basis of isotopic data from these I-S samples, the diagenesis of the Antalya Unit possibly occurred under a high geothermal gradient (> 35 degrees C/km), perhaps originating under typical extensional-basin conditions with high heat flow. The geochemical findings from I-S and smectites were controlled by diagenetic grade and can be used as an additional tool for understanding the basin maturity along with mineralogical data.Öğe High Risk of Malignant Mesothelioma and Pleural Plaques in Subjects Born Close to Ophiolites(ELSEVIER SCIENCE BV, 2013) Bayram, Mehmet; Dongel, Isa; Bakan, Nur Dilek; Yalcin, Huseyin; Cevit, Ruhiye; Dumortier, Pascal; Nemery, BenoitBackground: Ophiolites, a special sequence of geologic rock units, are known sources of naturally occurring asbestos. The aim of this study was to test whether the occurrence of malignant mesothelioma (MM) or pleural plaques (PPs) in the province of Sivas, Turkey, is determined by the proximity of the patient's birthplace to ophiolites and, if so, to establish the magnitude of the risk. Methods: The birthplaces of patients with MM or PPs (cases) and patients with prostate or breast cancer (control subjects), diagnosed between 2000 and 2010 and identified through a mandatory cancer registry or from hospital records (PPs), were located on a geologic map, and the nearest distance to ophiolites was measured. The relation of MM or PPs with distance to ophiolites was analyzed by logistic regression. Samples of soil and house plaster were determined by x-ray diffraction. Results: Patients with MM (n = 100) or PPs (n = 133) were born significantly nearer to ophiolites (median distance, 4.5 km for men, 0 km for women) than were patients with prostate cancer (n = 161) or breast cancer (n = 139) (median distance, 20 km for both). ORs were 1.6 (men) (P < .001) and 2.0 (women) (P < .001) for every 5-km decrease in the distance of birthplace to ophiolites for MM, compared with prostate and breast cancer, respectively. Conclusion: In this area without substantial industrial asbestos use, there is an association between the occurrence of mesothelioma (and of PPs) and the proximity of the subject's birthplace to ophiolites. CHEST 2013; 143(1):164-171Öğe Is living close to ophiolites related to asbestos related diseases? Cross-sectional study(W B SAUNDERS CO LTD, 2013) Dongel, Isa; Bayram, Mehmet; Bakan, Nur Dilek; Yalcin, Huseyin; Gulturk, SefaObjective: To determine the rate of pleural plaques and malignant mesothelioma and other factors that affect people living close to ophiolites. Methods: The study population was comprised of 2970 volunteers who resided <10 km from an ophiolitic unit. Control group comprised of 157 residents >25 km from ophiolites. Information gathered from the patients included presence of pleural plaques on chest X-ray, distance from ophiolites, gender, smoking status, duration of asbestos exposure, and body mass index (BMI). Mineralogical analysis of soil and rock samples was performed by X-ray diffraction. Results: Among the 2970 study participants, those who lived close to ophiolites, 9.8% had asbestos related disease (3 malignant mesothelioma, 289 pleural plaques). No asbestos related disease (ARD) was identified in the control group. Male gender (OR: 2.63, 95% 1.9-3.5, p < 0.001), advanced age (5% increase for every year p < 0.001), residential proximity to ophiolites (for every 1 km proximity, a 12% increase p < 0.001), and low BMI (for every 1 unit decrease, 3.6% increase p < 0.001) were associated with increased risk of ARD. Conclusion: The rate of ARD is higher in residents living close to ophiolites. Important risk factors for developing ARD were age, male gender, proximity to an ophiolite site, and low BMI. (c) 2013 Elsevier Ltd. All rights reserved.Öğe Metamorphic evolution of the Karakaya Complex in northern Turkey based on phyllosilicate mineralogy(SPRINGER WIEN, 2015) Tetiker, Sema; Yalcin, Huseyin; Bozkaya, Omer; Goncuoglu, M. CemalThe Triassic Karakaya Complex (KC) of the Sakarya Composite Terrane in northern Turkey is traditionally subdivided into two units. The Lower Karakaya Complex (LKC) consists of a tectonic m,lange with blocks of metabasic rocks, metacarbonates, meta-arenites and metapelites that have been affected by high pressure/low temperature metamorphism. It is followed by a low pressure/low temperature metamorphic overprint; the latter is the only metamorphic event in some tectonic slivers of the LKC. The Upper Karakaya Complex (UKC) units are primarily composed of diagenetic to low-grade metamorphic rocks, comprising Late Permian and Triassic cherts and blocks of OIB-type volcanic rocks interfingering with Anisian limestones. LKC slide-blocks of variable sizes are frequently observed within the UKC. Phyllosilicates of LKC and UKC were examined for their abundance, crystallinity, polytype and b cell dimension. Trioctahedral chamositic chlorites have IIb polytype and phengites 2 M (1) polytypes in the LKC units and 2 M (1) + 1 M + 1M (d) polytypes of phengitic dioctahedral illites in the UKC units. Kubler index data correspond to the low anchizone and epizone for the LKC units, and to the high diagenesis-low anchizone, and in part to the epizone for the UKC units. The b values of illites are consistent with a high-pressure facies series for the LKC, but only intermediate-pressure facies for the UKC. According to textural features, mineral paragenesis, clay transformations, index minerals, and b values, the lower-middle parts of the LKC represent an accretional tectonic setting, whereas the UKC units reflect pressure temperature conditions of an extensional basin affected by high heat flow.Öğe Mineral Chemistry of Chlorite and Illite/Mica in the Clastic Rocks of Karakaya Complex: Origin and Diagenesis/Metamorphism(TMMOB JEOLOJI MUHENDISLERI ODASI, 2018) Bozkaya, Omer; Yalcin, Huseyin; Tetiker, SemaThe Karakaya Complex units representing the relicts of environments related with the closure of PreJurassic Paleotethys Ocean outcrop within the Sakarya Composite Terrane. The compositions of illite/white micas change among muscovite-illite-phengite that illite/white micas with detrital and authigenic origins are close to muscovitic (Si-avg = 3.15, (Na+ K) avg = 0.81) and illitic compositions (Si-avg = 3.22, (Na+K)(avg) = 0.74), respectively. Paragonite (Si-avg = 2.96, Na= 0.78, K= 0.10) and NaK micas (Si-avg = 3.09, Na= 0.45, K= 0.34) are typical for extentional basins that are determined in the upper parts of the Turhal Metamorphites corresponding to the subgreenschist facies of the Karakaya Complex. The chlorites are of entirely trioctahedral and authigenic ones (Si-avg = 5.67, Fe avg = 5.05) have higher SiIVand lower FeVI contents in comparison with detrital ones. Chlorites have chamositic in the Hodul Unit, whereas clinochlore composition in the Orhanlar Unit. Detrital micas with high Mg (5.70-7.59) and Cr (0.09-0.16) contents are also identified in the Orhanlar Unit more common and in the Turhal Metamorphites as a few grains that are evaluated as evidences the presence Pre-Triassique ophiolitic rocks. The data of chlorite chemistry indicate the origins of felsic for Turhal Metamorphites, metabasic (probably remains of Paleotethys) for Orhanlar Unit and felsic and metapelitic with rich in Al and extreme rich in Fe. The data of chlorite geothermometry and phengite geobarometer indicate a temperature ranging from 150 to 300 degrees C and a pressure between 0.5-1.2 kbar, respectively. These values reflect the the high temperature-low pressure metamorphism for the upper part of the Karakaya Complex representing sub-greenschist facies and low-middle temperature-low pressure diagenesis conditions for sub-greenschist facies units of the Karakaya rift.Öğe Mineral Chemistry of Low-Temperature Phyllosilicates in Early Paleozoic Metaclastic Rocks, Eastern Tauride Belt, Turkiye(Mdpi, 2022) Bozkaya, Omer; Yalcin, HuseyinThe mineral chemistry of illite/mica and chlorites, together with the evaluation of textural data of low-temperature metaclastic rocks, plays an important role in determining their origin and metamorphic grade. This study aimed to investigate the chemical properties of phyllosilicates in early Paleozoic metaclastic rocks in the Eastern Tauride Belt, Turkiye. The textural (electron microscopy) and chemical (mineral chemistry analysis) analyses were performed on the samples representing different grades of metamorphism. The illites/micas and chlorites are observed as detrital (chlorite-mica stacks) and neoformation origin. Trioctahedral chlorites (chamosite) exhibit different chemistry for detrital and neoformed origin as well as the metamorphic grade. Tetrahedral Al and octahedral Fe + Mg increase, whereas octahedral Al decreases together with the increasing grade of metamorphism. The detrital chlorites have higher tetrahedral Al and Fe contents than their neoformed counterparts. Chlorite geothermometry data (detrital: 241->= 350 degrees C; neoformed: 201-268 degrees C) are compatible with the texture and illite Kubler index data. Illite/white-mica compositions display muscovite and Na-K mica. Tetrahedral Al and interlayer K + Na contents of illites/micas increase with metamorphic grade. Na-K mica and paragonite are observed as replacement-type developments within the detrital CMS. The obtained data indicate that phyllosilicate chemistry can be used effectively for determining the geological evolution of low-grade metamorphic sequences.Öğe Mineralogic evidences of a mid-Paleozoic tectono-thermal event in the Zonguldak terrane, northwest Turkey: implications for the dynamics of some Gondwana-derived terranes during the closure of the Rheic Ocean(CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS, 2012) Bozkaya, Omer; Yalcin, Huseyin; Goncuoglu, Mehmet CemalThe Zonguldak terrane is a Gondwana-derived continental microplate along the Black Sea coast in northwest Anatolia. It includes a Cadomian basement, with oceanic-and island-arc sequences, unconformably overlain by siliciclastic rocks of Ordovician to Middle Silurian age. After a period of deformation and erosion, late Lower Devonian (Emsian) quartzites and shallow-marine limestones unconformably cover Middle Silurian (Wenlock) graptolitic shales. Along several cross sections across the unconformity plane, the mineralogical characteristics of the Paleozoic sedimentary rocks in the Zonguldak terrane are studied to check whether this regional unconformity is only of epeirogenic nature or the result of a thermal event. In addition to the appearance of kaolinite in Devonian units, crystal-chemical data of illites show a sudden jump at the unconformity plane. The b cell dimension values of illites of Ordovician-Silurian units are somewhat higher than those of Devonian-Carboniferous units and show a drastic drop between the Silurian and Devonian units. The new mineralogic data indicate that the pre-Emsian rocks in the Zonguldak terrane experienced a thermodynamo event, prior to the Emsian transgression. This Caledonian-time event is also reported in east Moesian terrane but not noticed in the neighboring Istanbul-Zonguldak and in the west Moesian Balkan - Kreishte terranes. By this, it is suggested that Zonguldak and east Moesian terranes behaved independently from the Istanbul-Balkan terranes during the closure of the Rheic Ocean. They very likely docked to Laurussia during Emsian by strike-slip faults and remained thereon at its platform margin, where the Middle-Late Devonian shallow-platform conditions were followed by fluvial (lagoon and delta) conditions and deposition of coal during Late Carboniferous.Öğe Mineralogical and geochemical features of colored benthic foraminifers from Aegean and southwestern coasts of Turkey(MICRO PRESS, 2008) Yalcin, Huseyin; Meric, Engin; Avsar, Niyazi; Tetiker, Sema; Barut, Ipek F.; Yilmaz, Sener; Dincer, FeyzaWe studied a total of 24 genera and 41 species of modern benthic foraminifers with colored shells from 49 samples collected from the Gokceada region. Southwestern Bozeaada, eastern Mitilini in the northeast Aegean Sea and from different points along the shores of southwest Antalya. d((104)) reflection and MgCO3 content of shell calcite vary between 2.979-3.035 angstrom and 0.33-19.00 mole%, respectively. Mg/Ca and Sr/Ca ratios of whole shells range between 2.95-51.51 and 1.45-10.44 [mmol/mol]. These values are normalized to maximum and minimum concentrations in chemical analyses from whole shells and shell surfaces in colored and colorless foraminifers. Enrichments in metallic elements seem to be related to absorption depending on qualitative and quantitative measurements of shell structures, although variations are also related to mineralogical composition of shells. Hypothetically ions transferred with hot waters from active faults on the sea-floorand/or the ions transported with cold water runoff from land may cause abnormal enrichment of some metals within foraminifer shells and/or secondary metabolic enrichment of foraminifer shells during life.
