IDENTIFICATION OF CLAY MINERALS AND MICAS IN SEDIMENTARY ROCKS

Real possibilities of FTIR-spectroscopy application along with thermal analysis (TG/DTA) for examining clay minerals in rocks are presented. These methods were used for determination of mineral composition in sedimentary rock samples from the shaft No.4 Frenstat -West, Northern Moravia, CZ. Previously, the samples representing the basic clay mineral specimen were investigated by means of the following methods. In order to provide an adequate characterization of these samples, X-ray diffraction and X-ray fluorescence spectroscopy were utilized. As the individual clay minerals often occur in a form of mixed-layer clay minerals with various ratios of individual components, IR spectra and TG/DTA curves of mixtures (either natural or synthetic) were recorded, too. Clay minerals represented mainly by fine-crystalline illite (muscovite) with traces of kaolinite were predominant. Besides, carbonates (calcite, ankerite) and silica minerals occured in these samples, too. A presence of pyrites and coal matter was confirmed only by thermal analysis. Traces of feldspars were detected by means of FTIR spectroscopy in some rock samples.