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Genetical Investigation Of Balya-balikesir Lead-zinc MineralizationsOzisik, Gulsevim 01 January 2009 (has links) (PDF)
This thesis study is concerned with genetical investigation of Balikesir Balya Pb-Zn mineralization through the mineralogic-petrographic and geochemical examination of the core samples obtained from a total of 9 holes drilled by EczacibaSi ESAN Madencilik.
The Pb-Zn mineralization in Balya is mainly of vein-type. Wall rocks hosting mineralizations are dacite, dacite porphyry and microdiorite. Major types of alteration are silicification, carbonatization and calc-silicate alteration, each of which is further subdivided into early and late stages and overprinted by argillic alteration of probable supergene origin. The ore minerals are mainly Zn- and Pb-sulphides and are hosted by the rocks with late calc-silicate alteration that underwent pervasive late silicification and late carbonatization. Sulfide mineralization is spatially and temporally associated with the late silicification and carbonatization stages. Lateral-vertical correlation of drill logs suggest that thickness of the ore zone tends to decrease towards north.
The volcanic rocks hosting the mineralization have calc-alkaline nature. Major, trace and rare earth element (REE) geochemistry suggests either crustal contamination or subduction signature in the mantle source of the volcanics. Multi element patterns and discrimination diagrams collectively point to a post-collisional setting for their generation. Alteration geochemistry reveals that Fe2O3 and CaO are enriched during calc-silicate alteration in contrast to depletion of SiO2. Al2O3 and TiO2 are almost constant during late calc-silicate alteration. Enrichment of Fe2O3 and Na2O, and depletion of K2O characterize the silicified zones. Carbonatization is accompanied by strong enrichment of CaO and depletion of SiO2, Al2O3 and K2O.
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Volcanostratigraphy And Petrogenesis Of Suphan StratovolcanoOzdemir, Yavuz 01 March 2011 (has links) (PDF)
This study is concerned with volcanostratigraphic and petrologic evolution of the Sü / phan, which is a 4050 m high Quaternary stratovolcano in eastern Anatolia.
The eruptive products of Sü / phan Stratovolcano, including transitional mildly alkaline to calc-alkaline rocks, are lavas, domes and pyroclastics ranging in composition from basalts to rhyolites. Ar-Ar age data from different levels of the volcanostratigrafic succession yield a range of 0.76-0.06 Ma.
Textural features, wide temperature ranges obtained for intermediate members, and the linear trends of whole-rock geochemistry are strongly suggestive of magma mixing in the evolution of Sü / phan volcanics. Presence of crystal clots in many lavas suggests that cogenetic plutonic rocks were also involved in the mixing process. Comparison of whole-rock, melt inclusion and glass chemistry data of Sü / phan to data from experimental studies reported in literature indicate that the melt inclusions describe true liquid lines of descent from a common hydrous parent at pressures of ~500 MPa.
EC-AFC modeling of trace element and isotopic compositions reveals 2-8% crustal contamination in the differentiated lavas. REE modeling indicates that primitive rocks of Sü / phan volcanics were products of mixing of melts from spinel and garnet lherzolite sources, with contributions of 60% and 40%, respectively, in the mixture.
A two-stage petrogenetic model is proposed for Suphan stratovolcano. Mantle- derived melts stall and undergo chemical differentiation in a deep hot zone in lower to mid-crust / variably evolved melts ascending from this zone are arrested and mixed at a shallow level where they construct a sub-volcanic magma reservoir beneath Suphan.
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Investigation Of The Recharge And Discharge Mechanisms Of A Complex Aquifer System By Using Environmental Isotopes And Noble GasesArslan, Sebnem 01 February 2008 (has links) (PDF)
This study aims to determine the recharge, discharge and the mixing mechanisms of a
complex aquifer system located above the Kazan trona ore field using the environmental
isotopes of deuterium, oxygen-18, carbon-13 and carbon-14, chlorofluorocarbons (CFC-
11, CFC-12 and CFC-113) and the noble gas isotopes (He, Ne, Ar, Kr and Xe).
The groundwater system consists of three different aquifers: shallow, middle and deep.
The Akpinar formation lying between deep and middle systems acts as an aquitard.
Oxygen-18 and deuterium data showed an isotopic contrast between the shallow and
deeper aquifer systems and even between the unconfined and confined parts of the
middle and deep aquifers. The Noble gas temperatures indicated the average yearly air
temperatures in shallow aquifer system whereas the recharge temperatures came out to be
lower than todays in deep groundwater system. This finding is also supported by the
dissolved inorganic carbon&rsquo / s radiocarbon activities being close to the detection limits in
the same system. These activities together with the stable isotope data revealed there
might be evidence of recharge to the middle and deep aquifer systems under colder
climate conditions during the late Pleistocene.
CFC concentrations indicated modern recharge to the shallow aquifer system, whereas
the concentrations were close to the detection limits therefore CFC&rsquo / s were unable to date
the middle and deep aquifer systems however proved the existence of modern recharge to
this system.
Mantle-He escape to shallow aquifer system is believed to be along a deep buried fault
system located in downgradient areas.
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Geochemical Monitoring Of The Seismic Activities And Noble Gas Characterization Of The Geothermal Fields Along The Eastern Segment Of The Buyuk Menderes GrabenSuer, Selin 01 February 2010 (has links) (PDF)
This study aims the real-time monitoring of gases (CO2, N2, O2, H2, H2S, CH4, He, Ar) discharging from natural pools in the Tekke Hamam geothermal field (Denizli) in addition to the geochemical characterization of the field along with the Kizildere geothermal field, both located at the eastern segment of the Bü / yü / k Menderes Graben.
The continuous gas monitoring experiment (November 2007-October 2008) conducted in the Tekke Hamam geothermal field has revealed temporal variations in the gas compositions, gas flow rate and pool temperature. Different variation components, such as daily variation profiles and peak/Multi-day signals, are detected in the monitored data, which are mainly correlated with shallow and deep processes involving mainly meteorological factors and seismicity induced variations, respectively. Particularly, the coupled variations in the gas compositions and flow rate seem to correlate with seismicity induced permeability modifications within the subsurface during the absence of significant meteorological factors, such as high rainfall and varying atmospheric pressure.
The noble gas characterization of the fields have revealed both high 3He/4He and 4He/20Ne isotopic ratios, suggesting a mantle contribution of about 18% for Kizildere and 34% for Tekke Hamam, whereas the other noble gases (Ar, Ne, Kr, Xe) are of atmospheric nature. The different mantle contributions observed in both fields can suggest a different mantle-He flux variably contaminated by crustal helium. The chemical (cation-trace element-anion) and stable isotopic (& / #948 / 18O-& / #948 / D) contents of the thermal waters reveal high temperature water-rock interaction accompanied by the effects of deep origined gases (mainly CO2 and H2S) discharging from the fields.
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