Properties of altered coals associated with Carboniferous red beds in the Upper Silesian Coal Basin and their tentative classification

In the Czech and Polish parts of the Upper Silesian Coal Basin, red beds associated with the pre-Neoide tectonic structures are found. The occurrence of these beds is connected with changes in the development of the coal seams, in the macroscopic and microscopic character of coal and with its chemical and technological properties. These changes are due to the thermal and oxidation alteration of coal as a result of geological processes which, up to now, have not been clarified unambiguously. These altered coals were divided into groups according to their chemical and physical properties and vitrinite reflectance using statistical multicomponent methods. Coal samples classified as belonging to one of these groups correspond to a certain type of coal, characterized by a particular grade of thermal and oxidation alteration and petrographical composition