Investigation of placer gold and heavy mineral potential in stream beds in Alihoca Village (Niğde) location in Ulukışla basin

The aim of the thesis is to reveal the heavy metal potential, formation forms, origins, formation mechanisms, mineralogy and bed characteristics of the region by using samples taken from the stream beds in the region between Maden Village and Alihoca Village. To clarify the metal potential. The study area is located in Alihoca Village, Ulukışla district, in the south of Niğde province. The region presents a thick sequence consisting of deep sea sediments, pelagic carbonates, volcanic rocks in the Upper Cretaceous-Middle Eocene age scale, and dioritic, monzonitic and trachytic dykes cutting this sequence. Within the scope of this study, as a result of geological compilations of important units, Bolkar Carbonate Platform, Alihoca ophiolitic mélange, Çiftehan Formation, Ulukışla Basin and felsic pluton intrusions, Aktoprak Basin sediments and Quaternary fills were examined. Briefly, the stratigraphy of the Late Cretaceous-Cenozoic aged Ulukışla Basin consists of widely distributed volcanic lavas containing intrusions of felsic plutons and marine and continental sedimentary rocks, and at the base of these is the Bolkar Carbonate Platform and above this unit is the Alihoca ophiolitic mélange with tectonic contacts. Within the scope of the thesis, more than 40 samples were selected from over 80 samples obtained from 12 localities within the scope of detailed stream bed studies in the study area and their geological, mineralogical and geochemical analyzes were carried out. The samples taken within the scope of the field study were investigated using analytical methods in a laboratory environment. Analytical methods used on samples; grain size analysis, calcium carbonate (CaCO3) analysis and clay organic matter quantification, XRD measurements and clay heavy mineral separation method. Additionally, mineralogical and geochemical investigations were carried out on suitable samples and the results were interpreted. As a result of the examinations made on unattached sediment and soil samples taken from the stream bed in the grain size analysis, it was determined that the stream bed sediments and Holocene aged terrace soils were poorly sorted and all samples had positive and slightly negative values and generally showed strong coarse-skewness or very fine warpage. has been determined. As a result of the determination of the amount of calcium carbonate (CaCO3), clay and organic matter, it was determined that carbonate rocks were dominant in the terrestrial inputs and the decomposed grains were found in stream beds as crumbs. XRD patterns of Quaternary aged terrace soil samples obtained from stream beds were examined and the samples showed particularly widespread calcite, dolomite, quartz, small amounts of feldspar, hornblende, pyroxene, heavy minerals and clay minerals, and serpentine (lizardite), talc and zeolite (analcime) in the same localities. minerals have also been identified. The investigation of heavy mineral content and gold grains was investigated under two subheadings: transparent and opaque. Transparent ones are rutile, anatase, tourmaline and some ores, rock-forming minerals are calcite, quartz, pyroxene and feldspar, while opaque heavy minerals are commonly found such as sphalarite, pyrite and chalcopyrite. As a result of XRF-ICP analyzes (Geochemical analyses), the main (%) and trace (ppm) element amounts of unenriched stream bed sediments and enriched samples were determined and the results were interpreted with graphs and charts. As a result of the evaluation of sample analysis results taken from the field, in the region; It shows that these hydrothermally formed sulphide ores, which originate from Horoz Granite-Gradoniorite, are released by surface and ground waters and transported as sulphide and oxide. During its transportation, it precipitates along its path depending on its density and settles in karst systems, forming concentrated placer-type deposits. During the detailed determination of clay and organic substances, the Au element, which was assumed to be transported as grains, could not be determined, and the mineralized Au element could not be determined because it remained in the karst system and could not be transported to the stream bed.