Geology, mineralogy and geochemical properties of graphite deposits between Gökçeyayla and Akhisar (Han-Eskişehir)

Daha sonra doldurulaThere are amorphous graphite formations in the metamorphic rocks widely distributed around Gökçeyayla, Akhisar and Peçene (Eskişehir/Han). The geological, mineralogical and geochemical properties of graphite formations were investigated within the scope of this study. Graphite, which is among the critical raw materials by developed countries; It is aimed to reveal the geological and geochemical characteristics of the graphite quarry, which was operated in the 1960s, with the new technology. Paleozoic aged Afyon Metamorphites are located at the base of the study area. In this metamorphic succession, there are thin and medium thickness dark black colored amorphous graphite formations containing different carbon ratios. Triassic aged Çakmak Quartzite and Loras Formation overlie the Afyon Metamorphics unconformably. Above this, the Miocene aged Gebeceler Formation is unconformably overlain by the Seydiler Ignimbrite. Quaternary aged Alluvium units constitute the youngest units of the study area. Field studies were carried out in 3 different locations in the study area. These locations consist of Ataklı Stream, Elma Stream and Kezban Field. During the field studies, a total of 35 samples were taken from the rocks containing graphite and the surrounding rocks. Within the scope of mineralogical - petrographic studies on 10 samples selected from amorphous graphite samples; Polarizing Microscope, X-ray diffractor (XRD), Scanning Electron Microscope (SEM/EDX) and Raman Spectrum examinations were performed. In addition, geochemical analysis studies were carried out on these samples. In this context, Major Oxide, Trace and Rare Earth Element (REE) analyzes and Stable Isotope (δ13C, δ18O) analyzes of the samples were carried out. In Polarizing Microscope examinations, it was determined that graphite was settled in micro fractures and cracks, especially in marble samples. In XRD examinations, peak values of 3.34 and 2.12 were found. SEM/EDX examinations were performed on Agf 3 and Agf 11 samples. In EDX analysis, the carbon content of Agf 3 sample was 44.05%, and the carbon content of Agf 11 sample was 56.23%. As a result of Raman spectra acquisition, the peak values of the graphites were found to be 1343 in the D band, 1574 in the G band, and 2679 in the 2D band. According to the analysis results of amorphous graphite-containing rocks taken from Ataklı Stream, Elma Stream and Kezban Area locations within the scope of geochemical investigations, SiO2 content (39.98 - 90.16 wt%) is the highest in all regions. It was observed that the other main oxide contents decreased while the SiO2 content increased. Carbon content (CM) has the highest content with 8.59 wt% in Ataklı Stream Location. According to the trace element contents, Rb, Sr, U and Zr contents were observed to be richer in all regions compared to other trace elements. In addition, when the rare earth element (REE) contents were examined according to the knitting diagrams, it was seen that Eu gave negative anomaly. Finally, according to the δ13C stable isotope analysis results, the graphite samples were determined to be of biogenic origin. Keywords: Afyonkarahisar, Amorphous Graphite, Geochemistry, Stable Isotope, XRD, Raman Analysis