Sedimentological, petrographic and minerological analyses of Köprüağzi-Örenkale village (Başkale, Van) evaporite deposits

With this M.Sc. thesis, lithofacies and sedimentary structure definitions, sedimentological features, as well as petrographic texture and mineralogical characteristics of the evaporite sequence accumulated between Köprüağzı and Örenkale villages in the south of the province of Başkale in Van province were determined. For this purpose, a general evaporitic sequence was revealed by measuring and correlating the measured stratigraphic sections with the help of the stratigraphic relations and sedimentological features of the evaporitic units. It is determined that the evaporites in the sequence are composed of primary and secondary gypsum lithofacies and anhydrite. In addition, the presence of sedimentary structures in this gypsum has been revealed. With this field study, the petrographic texture properties of the evaporites investigated under the polarizing microscope were determined. In minerologic studies, it has been coincided to euhedral tabular, lenticular gypsum and orthorhombic anhydrite minerals, Mg-rich detritic and authigenic clay minerals, late diagenetic celestine crystals, quartz and feldspar grains within the gypsums, folds in laminated gypsum and rombohedral dolomite grains that replaced with gypsums during the late diagenesis. As a result of all these studies, it has been demonstrated that evaporites have a saline basin of continental-shallow origin, which is likely to be deposited in the playa lake environment and is affected by the formation conditions such as temperature, pressure and salinity during the sedimentation phase until late diagenesis process. In addition, climate, tectonism, hydrothermal solutions and stream effectiveness played an active role on these evaporites periodically.