Investigation of mineralogical, petrographical and geochemical features of sedimentary units in Banaz (Uşak) basin

Banaz Basin (Uşak) is a northeast-southwest trending basin filled with Neogene continental sediments associated with Uşak Neogene Basin in West Anatolia. The metamorphics of granite-schist, mica-schist, phyllite, marble blocks and lenses form the basement rocks in the examination field. These rocks belonging to the Menderes Massif are spread to the south and south east of Banaz District in the study area. The Neogene sequence, which fills the Banaz basin, is composed of fluvial, lacustrine and terrestrial deposits from the bottom to the top. Fluvial sediments comprise mainly cross layered gravel stone, sand stone and accompanying mudstone constituents. Fluvial sediments is much more widespread in the western and northern part in the basin and is conformably overlain by lacustrine sediments. Lacustrine deposits, widely spread particularly in the southern part of Banaz basin, consist of largely marl, calceraous mudstone and travertine. Sedimentary intercalations such as tuff, sandstone, conglomerate and claystone are observed locally within the lacustrine sequence. The Miocene aged Karaboldere Volcanites are spread in the east-southeast of the study area The Karaboldere Volcanics, which are composed of rhyodacite, trachyt, trachinadezite, andesite, tefrit, tuff and agglomerates, end with Miocene in the region. In the study area, fourteen deep drillings with depths ranging from 95 m to 580 m were performed by Turkey Coal Enterprises. Some levels of thin coal vein were cut in the drillings. Calcite, dolomite, anhydrite, feldspar, quartz and clay minerals were found as a result of XRD studies. Clay minerals were identified as smectite, kaolinite and illite. Depending on the clay content of the samples, the contents of Al2O3 and SiO2 are increased. The SiO2 percentage of the samples ranged from 0.52 to 48.45, while the percentage of Al2O3 ranged from 0.13 to 18.58. Calcitic and dolomitic samples were found to be quite low compared to the clay samples with high REE and total trace element. The samples were mostly formed under dry/semi-dry conditions by sedimentation and the cource rock was found to be acidic.