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    An approach to geochemical characterization of productive versus barren granitoids in terms of iron in Central Turkey
    (PERGAMON-ELSEVIER SCIENCE LTD, 2004) Kuscu, I; Gencalioglu-Kuscu, G; Sarac, C; Meinert, LD
    The granitoids associated with and without skarn type mineralizations in central Anatolia are. termed as productive and barren respectively. The Study of the relationships between plutonic rocks in the Central Anatolian Crystalline Complex in central Turkey suggests,:is a direct genetic connection between the composition of plutons, and their associated ore deposits. In order to discriminate between productive and barren granitoids, two Fe-skarn granitoids (Celebi and Karamadazi). and a series of barren plutons within central Anatolia were examined. The Karamadazi and Celebi granitoids are geochemically different from other barren plutons in Central Anatolia. The parameters governing the productivity of these granitoids were determined by principal component analysis (factor analysis) method. Based on this method, the factors controlling the geochemical characteristics of the Celebi granitoids are (Al2O3 divided by MgO divided by Fe2O3 divided by P2O5 divided by TiO2 divided by CaO)/(SiO2), (K2O + Rb)/(Na2O) and Rb/Sr ratios, and for the Karamadazi granitoid the (Fe2O3 divided by MnO divided by MgO divided by P2O5 divided byY)/(SiO2 divided by Rb) (FMMY/S) and (Na2O)/(K2O) ratios. These two granitoids are clearly distinguished front the barren Central Anatolian Granitoids (CAG) on Harker diagrams based oil these controlling factors (parameters). Barren CAG plutons are different front the productive Celebi granitoids in their higher silica content and generally higher total alkali values. This study suggests that iron-producing granitoids are less differentiated and receive little contribution from continental crust compared to the barren granitoids. Higher apatite and zircon abundance in the Celebi granitoids suggest that the Celebi granitoids have more I-type characteristics compared to barren plutons of CAG. The Karamadazi granitoid is the most striking example for the granitoids in CAG, having a higher contribution front the continental crust ass evidenced by higher Rb. Ba. Th, the highest mean Sc, V, and mean Zr, Y, Ni contents. Based on the factor analysis, it is proposed that the Karamadazi granitoid displays geochemical characteristics similar to the Terlermez and Agacoren granitoids of CAG. The factor analyses indicated that the first two factors are about the same for both the Fe-producing Celebi and Karamadazi granitoids. Therefore. this similarity has let to a conclusion that the productivity or non-productivity of the granitoids in Central Anatolia can be tested by examining and comparing the distribution of granitoids in diagrams designed according to the factors defined in this study. (C) 2004 Elsevier Ltd. All rights reserved.
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    Geochemical signatures of granitoids associated with skarns in central Anatolia
    (TAYLOR & FRANCIS INC, 2001) Kuscu, I; Gencalioglu-Kuscu, G; Erler, A
    Many studies have shown systematic correlations between the composition of plutons worldwide and the metal contents of associated skarns. This is the first report of similar correlations between plutons and the skarns of the Akdagmadeni, Akcakisla, and Keskin districts in Central Anatolia. Herein, die genetic associations of skarn occurrences are investigated using the geochemical compositions of the intrusives. In terms of major- and trace-element data, the granitoids associated with skarns show important differences. Three general groups of plutons, are distinguished, and the distinction among them is based largely on major-element data. In general, the granitoids associated with Pb-Zn skarns in all three districts are classified as subalkaline/calc-alkaline, based on TAS and AFM diagrams, respectively. The Akdagmadeni and Keskin granitoids display S-type characteristics, and those of Akcakisla display I-type characteristics. As a whole, the granitoids in all districts display major-element geochemical characteristics (Harker diagrams) that typify plutons associated with worldwide Zn, W, Mo, and Sn skarns. These data probably indicate that some other elements, like W in the Akdagmadeni district, and Mo + Sn in the Keskin district, could be associated with these skarns. Similarly, the granitoids of Akdagmadeni and Akcakisla have trace-element geochemical signatures (Zr versus Ba and Zr versus Rb/Sr diagrams) that typify plutons associated worldwide with Zn, Cu, Mo, and W skarns. This also helps to underline the possible association of W and Mo skarns in the Akdagmadeni district, and Cu skarns in the Akcakisla district. The average K2O/Na2O ratios of the plutons also serve to differentiate the granitoids associated with different types of skarns. The average K2O/Na2O ratio of the Keskin pluton it; 1.23, close to that of plutons associated with major Mo and Sn skarns. On the other hand, the average K2O/Na2O ratio of Akcakisla granite is very close to 1.0, close to that of plutons associated with major Cu (and W?) as well as Pb and Zn. Therefore, these skarns should be investigated in terms of the potential for those elements. This suggests new exploration possibilities for the Akcakisla, Akdagmadeni, and Keskin districts.
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    Influences of human activities and agriculture on groundwater quality of Kayseri-Incesu-Dokuzpinar springs, central Anatolian part of Turkey
    (SPRINGER-VERLAG, 2003) Elhatip, H; Afsin, M; Kuscu, I; Dirik, K; Kurmac, Y; Kavurmaci, M
    Human activities and agriculture have had direct and indirect effects on the rates of contamination of groundwater in the Incesu-Dokuzpinar spring area. Direct effects include dissolution and transport of excess quantities of fertilizers with associated materials and hydrological alterations related to irrigation and drainage. Indirect effects may include changes in water-rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agricultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3, N-2, Cl, SO42, H+, K, Mg, Ca, Fe, Cu, B, Pb, and Zn, as well as a wide variety of pesticides and other organic compounds. For reactive contaminants like NO3, it is recommended that a combination of hydrochemical and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. The water type of Dokuzpinar springs is mainly Na-Mg-Ca-Cl-HCO3. Note that the water types of the springs were directly related to the hydrogeochemical properties of outcrops at the study area. Thus, the high concentration of Ca2+ and HCO3 is mainly related to the high CO2 contents in the marbles, whereas the high Na concentration arises from the existing syenite, volcanic ash, basalt, and clay units, although the Incesu-Dokuzpinar springs cover most of the drinking and irrigation water demands of this area. The high concentrations of NO3 and NaCl show that the area around the springs is continuously being contaminated by untreated sewage and agricultural wastes, especially during dry periods. Therefore, this approach is based on the vulnerability studies of the catchment area, determination of the transfer time of the pollutant, and the water-bearing formations of Incesu-Dokuzpinar springs. Vulnerability in this study is defined as the intrinsic hydrogeochemical characteristics of an aquifer, which may show the sensitivity of groundwater to be contaminated by different human activities.
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    Post-collisional H-type granitoid magmatism in Central Anatolia and time-space relation with Fe-oxide mineralization
    (MILLPRESS SCIENCE PUBLISHERS, 2003) Kuscu, I; Kuscu, GG; Soylu, M; Eliopoulous, DG
    The distribution, in both space and time, of the mineral deposits of the Central Anatolia reveals some interesting and enigmatic features of mineralization in a collision related setting. Central Anatolia is a polymetallic metallogenic province hosting mineral deposits of various size and type. Present study concerns with the formation and distribution of the Fe-oxide mineralization in terms of granite metallogeny, and reveals the genetic coexistence of H-type post-collisional granitoid magmatisin and Fe-oxide mineralization.
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    Tectonic setting and petrogenesis of the Celebi granitoid, (Kirikkale-Turkey) and comparison with world skarn granitoids
    (ELSEVIER SCIENCE BV, 2002) Kuscu, I; Kuscu, GG; Meinert, LD; Floyd, PA
    Many studies have shown systematic correlations between the composition of plutons worldwide and the metal content of associated skarns. This is the first report of similar correlations between the composition of Celebi granitoid and skarns of the Celebi district in Central Anatolia, Turkey. The Celebi district is well known for its polymetallic Fe-Wand Cu vein ores. These are hosted by calcic skarn zones. Both exoskarns (pyroxene-gamet) and endoskarns (epidote-pyroxene) occur in the district formed mainly along the granitoid contacts and along the fractures within the marble. Based on mineralogy, petrology and geochemistry, two different igneous rocks were recognized in the Celebi granitoid, referred to as leucocratic (felsic) and mesocratic (intermediate) Celebi granitoid. The leucocratic Celebi occurs as dominant rock type, and is classified as granite. The mesocratic Celebi is not widespread and is classified as adamellite, tomalite, quartz monzonite and quartz monzodiorite. The mesocratic Celebi has I-type characteristics, and have subalkaline, calc-alkaline and metaluminous characteristics like most worldwide skarn granitoids. A post-collisional tectonic setting is proposed on the basis of field evidence, the relative timing of intrusions with respect to metamorphic and obducted ophiolitic rocks and trace element geochemistry. The high abundance of La and Ce and the enrichment of V in mafic components suggest that Celebi granitoids are formed by partial melting of mantle rocks, but have been contaminated by interaction with continental crust involving possible magma mixing processes (i.e. mixing of coexisting felsic and mafic magmas). In the district, the mesocratic type and mafic microgranular enclaves (MME) mainly within leucocratic type represent a mafic underplating magma that was mixed with and/or injected into felsic magma of the leucocratic type. The present study shows that Fe mineralization is associated with mesocratic Celebi type, whereas W mineralization is associated with leucocratic type. Mesocratic Celebi granitoid is significantly different from the worldwide average of plutons associated with Fe skarns. In particular, MgO vs. SiO2, FeOt+CaO+Na2O/K2O vs. SiO2, Fe2O3/Fe2O3+FeO vs. SiO2 and V vs. Ni vary from typical values (are lower than values typical for plutons associated with Fe skarns) for plutons associated with Fe skarns. Instead, it resembles the geochemical characteristics of plutons associated with worldwide Cu and possibly An skarns. This suggests new exploration possibilities for copper and gold in the Celebi district. (C) 2002 Elsevier Science B.V. All rights reserved.