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Ermis I.U.,Mineral Research and Exploration General Directorate
12th International Multidisciplinary Scientific GeoConference and EXPO - Modern Management of Mine Producing, Geology and Environmental Protection, SGEM 2012 | Year: 2012

Leaching of strontium sulfate (SrSO4) concentrate in the presence of nitric acid (HNO3) was investigated in this study. The effects of some operating parameters such as stirring speed, leaching temperature, acid concentration, solid/liquid ratio and particle size on the leaching of SrSO4 were determined and Sr was obtained from the solution 91.35% efficiency at 400 rpm, 60 °C, 1M, 2 g/500 mL, -75 μm respectively. © SGEM2012 All Rights Reserved by the International Multidisciplinary Scientific GeoConference SGEM. Source

Ozguner A.M.,Mineral Research and Exploration General Directorate
Journal of African Earth Sciences | Year: 2014

Representative sampling of the raw materials used to make Portland cement, correct calculations for the possible clinker mixtures, sufficient reserves of the raw materials and selection of the correct infrastructure for the location of a cement factory are essential to the protection of the great investment in the factory.The results of chemical analyses of pipe samples taken in the field at right angles to the strikes of favourable limestone, clay, shale, and marl outcrops were used in Kind's lime saturation formula for clinker calculations of the possible mixtures. The cement modulus values were calculated using the corresponding clinker oxide ratios and were confirmed to be within the standard intervals for positive cement raw material mixtures.The most promising raw material source, a double lithologic mixture of limestone and mudstone was found during the prospection in north of Bilecik Province, where rhyolitic tuff outcrops with pozzolanic properties also exist. Some marble quarries nearby have been inclined to dispose of their marble wastes for use in cement production to prevent polluting the environment with them. The nearby Gemlik fertiliser factory provides inexpensive waste gypsum that can be used as a cool cement mixing material. The limestone, mudstone and trass raw material reserves in this area were calculated to be sufficient for the factory's requirements for more than 100. years of operation as results of the detailed geological mapping.The regional infrastructure is most suitable for distribution and marketing of cement products. The cement factory described in this study has been producing cement for the last 3. years, after coring and testing of the raw material reserves. © 2014 . Source

Girgin I.,Hacettepe University | Yorukoglu A.,Mineral Research and Exploration General Directorate
Russian Journal of Inorganic Chemistry | Year: 2010

The effect of methanol on the solubility of Nd2O3 in HCl medium in the temperature range of 25-55°C were studied. HCl-CH 3OH was observed to be a better solvent than HCl-CH 3OH-H2O and hydrochloric acid for the dissolution of Nd2O3 mainly due to prevention of neodymium hydroxide and dissolution increased with increase of HCl concentration even at high HCl concentrations. Presence of methanol in the medium was determined to cause corresponding decreases in conductivity, ESCE, pH values with corresponding increase in ER values. Neodymium compounds formed in HCl-CH3OH medium at 25°C were isolated and identified using X-ray diffraction, thermal and chemical analysis methods and their thermal behaviour were investigated between 25-1100°C. NdCl3 × x 1CH3OH and NdCl3 × x 2CH 3OH × 4.14H2O (x 1 + x 2 = 2.8) were formed in non-aqueous medium and these compounds were converted into NdCl3, NdCl2.37 and NdCl3 × 0.47CH 3OH with complete and partial loss of water and methanol around 240°C respectively. Methanol was completely removed around 390°C with formation of NdCl2.37 (77.5%) and NdOCl (22.5%) and NdOCl was detected as the major stable phase above 700°C. © 2010 Pleiades Publishing, Ltd. Source

Gursu S.,Mugla University | Gursu S.,University of Kansas | Moller A.,University of Kansas | Goncuoglu M.C.,Middle East Technical University | And 5 more authors.
Precambrian Research | Year: 2015

New geochemical, Sr/Nd isotope and zircon U-Pb LA-ICP-MS data from the Derik Volcanics in the Southeast Anatolian Autochthone Belt of Turkey are consistent with an Andean-type Cadomian arc that developed along the northern edge of the Arabian Plate during the Late Neoproterozoic. The Derik Volcanics represent a volcanic complex including andesites, rhyolites and basalts, with volcanoclastic and fluvial sediments. They are unconformably overlain by playa sediments with Early Cambrian ichno-fossils, followed by Middle Cambrian-Silurian shallow marine deposits.Geochemically, the Derik Volcanics (DV) display transitional-calcalkaline affinities. On Th/Nb-Ti/Zr diagram, DV display negative trends from rhyolites to late to early-stage andesites and mafic dykes, respectively. The REE patterns are highly to moderately fractionated, with [(La/Yb)N=5.20-6.77 in late-stage andesites, 4.38-10.51 in rhyolites, 2.58-4.65 in the early-stage andesites, and 2.51-4.21 in mafic dykes]. Normalized trace element and REE diagrams display Th, La, Ce, Sm enrichment and depletion of Nb, Ti and Eu as is typical for Andean-type active continental margin igneous rocks. The enrichment of LILE and LREE, combined with depletion of HREE also suggests that the Derik Volcanic rocks were formed in relation with a subduction zone. Negative Eu anomalies (Eu/Eu)N, range from 0.50 to 1.81, indicates fractional crystallization of feldspar. The DV have positive e{open}Nd (+0.15 to +4.20) and mean model ages of 1.28Ga for the early-stage andesites, 1.34Ga for rhyolites, 1.35 for late-stage andesites, and 1.36Ga for mafic dykes. The positive e{open}Nd(T) data show that DV are product of mantle-derived magmas. Lower 143Nd/144Nd isotope ratios than the depleted MORB mantle (DMM) source indicate that the DV may have been contaminated by crustal material during magma genesis. Geochemical modeling shows that all four volcanic rock types may have been formed by different percentages of batch melting of DMM and subducting slab sources.Zircon LA-ICP-MS data give crystallization ages of 581.4. ±. 3.5. Ma (. n=. 7) and 559.2. ±. 3.2. Ma (. n=. 3) for the early and late-stage andesitic rocks, as well as ages of 569.6. ±. 1.6. Ma (. n=. 17), 571.6. ±. 1.9. Ma (. n=. 18), 575.4. ±. 4.3. Ma (. n=. 6) for the rhyolites.The geological and geochemical features together with the new age data suggest that the Derik Volcanics formed along a continental arc in the course of the southward subduction of Prototethys oceanic lithosphere along the northern margin of the Arabian Plate, which is attributed to a late-stage phase of the Cadomian Orogeny of the Pan-African cycle. © 2015 Elsevier B.V. Source

Albayrak M.,Mineral Research and Exploration General Directorate | Ozguner A.M.,Mineral Research and Exploration General Directorate
Turkish Journal of Earth Sciences | Year: 2013

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 periphery of the underlying intrusions. The bentonitic cap rock suggests that the diagenesis diminished vertically with the weakened phreatomagmatic activity up to the overlying limestone. The lack of sedimentary evaporite minerals and scarcity of boron-bearing authigenic K-feldspar indicate a nonsaline-alkaline depositional and diagenetic environment during the zeolitic transformation. Geochemical data from the zeolitic tuff samples indicated that the main diagenetic factors were hydrolysis of the glassy tuff in an open hydrologic system, under high heat flow rates and one of several scales of ion transfer. Zeolitisation developed with a significant loss of alkaline elements and iron oxide, which were compensated for by an important gain in the alkaline earth elements and absorption of strontium. The rhyolitic glass was altered by hydrolysis to form smectite and clinoptilolite, resulting in the release of excess silica that was not removed from the system but was changed in crystal form to opal-CT. © TüBi̇TAK. Source

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