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Öğe Clastour: A Computer Program for Classification of the Minerals of the Tourmaline Group(Pergamon-Elsevier Science Ltd, 2002) Yavuz, Fuat; Gültekin, A. H.; Karakaya, Muazzez ÇelikTourmaline is the most important borosilicate mineral and a dominant carrier of boron, occurring in different geologic environments. Recently, many investigators have focused on the enhanced understanding of crystal chemistry of this complex mineral group. CLASTOUR is a program package for IBM-compatible personal computers that can be used for classification of the tourmaline group. The program classifies most of the currently valid tourmaline end-members together with other hypothetical end-members. Because it is difficult to establish OH- and O2(-) contents at the V- and W-sites without carrying out bond valance sum (BVS) calculations, CLASTOUR gives alternative names for some tourmalines including dominant O2- anion at their V- and W-sites. The program is developed to edit, to store and to calculate the tourmaline analyses obtained both from electron-microprobe and wet-chemical studies. It is designed to calculate entered tourmaline analyses into cation and molecular percentages, to share cation site-allocations at the different structural positions and to give mole percent of the end-members of alkali-, calcic-, and X-site vacant-group tourmalines. Thus, CLASTOUR makes it possible to plot various types of binary and ternary diagrams under the Grapher software. This program is a user-friendly software with pull-down menus, base-function keys, help menus, extensive error codes and mouse options. The compiled program together with the test data files and graphic files is approximately 1160 kB.Öğe GEOLOGY AND CONDITIONS OF FORMATION OF THE ZEOLITE-BEARING DEPOSITS SOUTHEAST OF ANKARA (CENTRAL TURKEY)(CLAY MINERALS SOC, 2015) Karakaya, Muazzez Celik; Karakaya, Necati; Yavuz, FuatThe pyroclastic sediments studied here contained varied amounts of zeolite and were formed in the saline alkaline Tuzgolii Basin following the alteration of dacitic volcanic materials during the Early to Late Miocene. The present study focused on the geological-geochemical properties of the zeolites and describes their formation. Mineralogical and chemical compositions were determined by X-ray diffraction, scanning electron microscopy, optical microscopy, and inductively coupled plasma mass spectrometry. Results indicated that the zeolitic tuffs consisted mainly of heulandite/clinoptilolite (Hul/Cpt), chabazite, erionite, and analcime associated with smectite. Smectite, calcite, and dolomite are abundant in the clay and carbonate layers which alternate with the zeolitic tuffs. K-feldspar, gypsum, and hexahydrite (MgSO4 center dot 6H(2)O) were also found in some altered tuffs and clay-marl layers as accessory minerals. The zeolite and other authigenic minerals showed weak stratigraphic zonation. Some vitric tuff layers contained no zeolite minerals and others were found to consist of almost pure Hul/Cpt and chabazite layers with economic potential. The rare earth elements (REE), large ion lithophile elements (LILE), and high-field strength elements (HFSE) in the Hul/Cpt-rich tuffs and vitric tuffs were enriched or depleted relative to the precursor rock, while many major elements were slightly or significantly depleted in all zeolitic tuffs. The amounts of REE in the chabazite- and erionite-rich tuffs were generally smaller than those in the precursor rock. The middle and heavy REE (MREE and HREE, respectively) were abundant in the Hull Cpt-rich tuffs, tuffs, and smectitic bentonites. Chondrite-normalized REE values of the sample groups are characterized by sub-parallel patterns with enrichment in LREE relative to HREE. The mineral assemblages and geological setting indicated that zeolite diagenesis occurred in a saline-alkaline basin. The delta O-18 and delta D compositions of the Hul/Cpt, chabazite, and smectite indicated that the minerals formed at low to moderate temperatures and that some of the zeolitization occurred due to diagenetic alteration under closed-system conditions that varied according to the nature of the basin and with the composition and physical properties of the volcanic materials.Öğe Mineral Chemistry of Barium- and Titanium-,Bearing Biotites in Calc-Alkaline Volcanic Rocks From the Mezitler Area (Balıkesir-Dursunbey), Western Turkey(GEOCHEMICAL SOC JAPAN, 2002) Yavuz, Fuat; Gültekin, Ali Haydar; Örgün, Yüksel; Çelik, Nurgül; Çelik Karakaya, Muazzez; Şaşmaz, AhmetBarium- and titanium-bearing biotites from Miocene volcanic rocks of Mezitler area, eastern Balikesir, western Turkey are studied. The chemical composition of volcanic rocks range from andesite to rhyodacite. The iron-enrichment index of micas (average I.E. = 0.40) is intermediate between annite and phlogopite. The biotite phenocrysts contain up to 1.72 wt.% BaO and 5.90 wt.% TiO2, with the average formulae (K-0.807 Na-0.131 Ca-0.036 Ba-0.027) (Mg-1.404 Fe-0.800(2+) Fe-0.131(3+) Ti-0.303 Al-0.056 Mn-0.023) (Si-2.832 Al-1.167) O-10 [(OH)(1.976) Cl-0.024]. The BaO content of electron-microprobe micas is positively correlated with the Al2O3, TiO2, and FeO contents, and with the I.E., and is negatively correlated with the SiO2, K2O, and MgO contents. Ba- and Ti-rich micas are generally found in potassic igneous rocks, in subalkaline and alkaline gabbroic rocks and in contact metamorphic rocks, whereas Ba- and Ti-bearing micas in this study occur in calc-alkaline volcanic rocks that hosted manganese-oxide and barite deposits. Most of the phenocrysts analyzed have deficiencies in their octahedral and partly interlayer sites. Deficiencies in the octahedral sites may arise from the Ti-vacancy and partly the Ti-tschermakite substitution. On the other hand, deficiencies in the interlayer-site are due to the replacement of K by Ba. The substitution mechanism in the Mezitler micas is characterized by Ba + 2Ti + 3Al = (K+Na+Ca) + 3(Mg+Fe+Mn) + 3Si, with an excellent correlation coefficient. In terms of aluminum and titanium contents, micas from the Mezitler area lie on a similar trend parallel to that for metasomatic phlogopites from Canary Island xenoliths, which overlap the field for micas from the Ilha da Trindade xenolith, South Atlantic. Biotite compositions from the Mezitler area fall between the quartz-fayalite-magnetite (QFM) and nickel-nickel oxide (NNO) oxygen fugacity buffers. All these show that Mezitler micas with low to moderate Ba- and Ti-contents may be formed from magmas in a subduction-enriched sub-continental lithospheric mantle environment.Öğe Mineralogical and physico-chemical properties of Heu-type zeolitic rocks SE of Ankara, central Turkey(MINERALOGICAL SOC, 2017) Karakaya, Muazzez Celik; Karakaya, Necati; Yavuz, FuatThis study focused on the mineralogical and physico-chemical properties of heulandite/clinoptilolite (Heu/Cpt)-rich zeolitic tuffs SE of Ankara (Turkey) and evaluated their potential for use as adsorbents. The main Heu/Cpt minerals correspond to the intermediate type and the Cpt-type of the heulandite series. Minor chabazite, erionite and rarely analcime and accessory feldspars, mica, smectite, and quartz were also detected. Three types of Heu were recognized according to their thermal behaviour. Cpt (type-III Heu) was thermally stable at 600 degrees C, whereas type-I Heu collapsed and type-II Heu partially collapsed. The Si/Al ratios of the Hul/Cpt ranged from 3.54 to 5.03, the G parameter (G = Ca/Al + 0.115* Al) varied between 0.78 and 1.85 and Al + Fe3+ varied between 6.27 and 8.00. The Na, K and Ca contents of Heu/Cpt varied widely and the Heu had an intermediate composition between types II and III. The Mg + Ca content is greater than the Na + K content in Heu-type II and smaller in Heu-type III zeolites. The BET surface area and the pore-size of the samples varied between 10.15 and 194.27 m(2)/g, and between 1.41 and 12.42 nm, respectively. The N-2 adsorption and desorption isotherms were comparable, but the adsorption/desorption capacity is greater in type III than in type II Heu zeolites. The cation exchange capacities of the Heu/Cpt-rich samples ranged from 185 to 280 meq/100 g.Öğe Mineralogy and geochemical behavior of trace elements of hydrothermal alteration types in the volcanogenic massive sulfide deposits, NE Turkey(Elsevier Science Bv, 2012) Karakaya, Muazzez Çelik; Karakaya, Necati; Küpeli, Şuayip; Yavuz, FuatVolcanogenic massive sulfide (VMS) deposits of the Eastern Pontides, Turkey, are hosted by the Maastrichtian-Eocene dacite and rhyodacite series, accompanied by lesser andesite and basalts, as well as their pyroclastic equivalents, with tholeiitic to calc-alkaline affinity. The ore mineral assemblages are chalcopyrite, sphalerite, galena, chalcocite, covellite, bornite, and tetrahedrite. Potassic-, phyllitic- (sericitic), argillic- (kaolinitic and smectitic), silicic-, propylitic- and hematitic-alteration is commonly associated with these deposits. HFSE, LILE, TRTE and REE contents show strong variability in different alteration types resulting from interaction with acid or alkaline fluids. Sample groups showed chondrite-normalized enrichment of LREE relative to HREE and sub-parallel trends, except for the hematitic- and phyllitic-alteration types. MREE are strongly depleted in the zones of most intense silicification and kaolinization. Most sample groups have strongly- to slightly-negative Eu anomalies, ranging from 0.35 to 0.88 (mean); hematitic- (1.45) and propylitic-altered rocks (1.11) have slightly- to moderately-positive anomalies. The negative Eu anomalies indicate the low temperatures of fluids (<200 degrees C). In contrast, the positive Eu anomalies result from high-temperature hydrothermal conditions (>200 degrees C). No Ce anomaly was observed, except for phyllitic alteration where a slight positive anomaly was noted. The chondrite-normalized trace and REE patterns of the altered rocks are similar to each other, suggesting that they were derived from a common felsic source. The alteration groups formed from acid, intermediate, and alkaline hydrothermal solutions. Some transition, base and precious metals and volatile elements were clearly enriched, especially in the hematitic-, silicic-, kaolinitic- and phyllitic-altered samples. The other elements exhibit different behaviors in different sample groups. REE behavior is relatively immobile in the silicic-, hematitic-, kaolinitic- and partially in moderately- and propylitic-altered rocks, based on mass-balance calculations. LILE and HFSE appear mobile in the altered sample groups, except in the propylitic-altered rocks. TRTE behave as relatively immobile in most of samples, except in some of the silicic- and phyllitic-altered rocks, and especially in the hematitic-altered samples. HFSE, most of the transition (W, Mo, Cu, and Sb) and some other trace elements (Pb, As, Hg, Bi, Se and TI), are enriched in the hematitic-altered samples and in the some silicic-altered samples. The highest As, Bi, Mo, Se and Hg concentrations in the hematite-altered samples can be used to distinguish other alteration types and may be a useful indicator in a prospect-scale base metal exploration. (C) 2012 Elsevier B.V. All rights reserved.Öğe Trace-element, rare-earth element and boron isotopic compositions of tourmaline from a vein-type Pb-Zn-Cu +/- U deposit, NE Turkey(TAYLOR & FRANCIS INC, 2011) Yavuz, Fuat; Jiang, Shao-Yong; Karakaya, Necati; Karakaya, Muazzez Celik; Yavuz, RehaThis paper reports trace-element, rare-earth element (REE) and boron isotopic compositions of tourmaline in the Asarck granitoid and quartz veins at Sebinkarahisar. Abundant tourmaline occurs in the vein-type Pb-Zn-Cu +/- U deposit, within the northeastern Pontide Metallogenic Belt, both within the Late Cretaceous Asarck granitoid and in associated quartz-tourmaline veins. Tourmaline in the granitoid forms as rosettes up to 1.5cm in diameter, whereas in quartz-tourmaline veins a few centimetres to a few metres wide, it occurs as black needles and masses that cut the pluton. We present a systematic geochemical study of these tourmalines - all of the schorl-dravite series. Tourmalines from the quartz veins contain high concentrations of ore metals such as Ag, Bi and Zn and have higher Sr, Cr and Sn contents than tourmalines in the Asarck granitoid. Tourmalines from intensively altered parts of the pluton are characterized by higher concentrations of trace elements such as Ba, Rb, V, Sc, Th and Zr compared with occurrences in the quartz veins and in the fresh and less-altered granitoid. Chondrite-normalized patterns of REEs in tourmalines from the Asarck granitoid are generally similar to those of tourmalines in the quartz veins. All vein tourmalines, however, are characterized by heavy REE enrichments, in sharp contrast to those in the granitoid. Boron isotopic compositions of tourmalines range from -14.0 to -2.2 parts per thousand and fall within the 11B range of this mineral in granite-related settings. Tourmaline rosettes from the Asarck granitoid show relatively lighter 11B values (-14.0 to -12.2 parts per thousand) in comparison with those in the quartz veins (-10.4 to -2.2 parts per thousand).Öğe A Windows program for calculation and classification of tourmaline-supergroup (IMA-2011)(PERGAMON-ELSEVIER SCIENCE LTD, 2014) Yavuz, Fuat; Karakaya, Necati; Yildirim, Demet K.; Karakaya, Muazzez C.; Kumral, MustafaA Microsoft Visual Basic program, WinTcac, has been developed to calculate structural formulae of tourmaline analyses based on the Subcommittee on Tourmaline Nomenclature (STN) of the International Mineralogical Association's Commission on New Minerals, Nomenclature and Classification (IMA-CNMCN) scheme. WinTcac calculates and classifies tourmaline-supergroup minerals based on 31 0 atoms for complete tourmaline analyses. For electron-microprobe-derived tourmaline analyses site occupancy can be estimated by using the stoichiometric H2O (wt%) and B2O3 (wt%) contents. This program also allows the user to process tourmaline analyses using 15 cations and 6 silicons normalization schemes. WinTcac provides the user to display tourmaline analyses in a various classification, environmental, substitution, and miscellaneous plots by using the Golden Software's Grapher program. The program is developed to predict cation site-allocations at the different structural positions, including the T, Z, Y, and X sites, as well as to estimate the OH1-, F1-, Cl1-, and O2- contents. WinTcac provides editing and loading Microsoft Excel files to calculate multiple tourmaline analyses. This software generates and stores all the calculated results in the output of Microsoft Excel file, which can be displayed and processed by any other software for verification, general data manipulation, and graphing purposes. The compiled program code is distributed as a self-extracting setup file, including a help file, test data files and graphic files, which are designed to produce a high-quality printout of the related plotting software. (C) 2013 Elsevier Ltd. All rights reserved.Öğe A Windows program for chlorite calculation and classification(PERGAMON-ELSEVIER SCIENCE LTD, 2015) Yavuz, Fuat; Kumral, Mustafa; Karakaya, Necati; Karakaya, Muazzez C.; Yildirim, Demet K.A Microsoft Visital Basic program, WinCcac, has been developed to calculate the structural formulae of chlorite. WinCcac classifies rock-forming chlorite group minerals based on 14 oxygens for complete chlorite analyses. For electron-microprobe-derived chlorite analyses site occupancy can be estimated by using the stoichiometric H2O (wt%) and Fe2O3 (wt%) contents. The program is created to predict cation site-allocations at the different structural positions such as the tetrahedral, octahedral, and interlayer sites. Furthermore, various chlorite geothermometers based on an empirical approach are carried out to specify the condition of formation temperature. WinCcac allows the user to enter and load multiple chlorite analyses in its own data entry window, to edit and load Microsoft Excel files in estimating and classifying chlorite data, and to generate and store all the calculated results in the output of Microsoft Excel file for further data evaluation and graphing purposes. (C) 2015 Elsevier Ltd. All rights reserved.
