Petrographic characteristics of Neogene lignites from the Ptolemais and Servia Basins, Northern Greece

In this study the petrographic analysis results of Ptolemais and Servia Neo gene lignites, Northern Greece, are presented. The geological position, lit hotype, and maceral content of these lignites, as well as some chemical par ameters and changes in, the reflection of different macerals, are described . The interdependence between maceral content and environmental conditions in the process of peat formation is traced. Petrographic analysis shows tha t coals are represented by different kinds of lignites from dark brown to b lack, semibright lignites, consisting mainly of the coal lithotype humoclar ain rare strips and bands of blight humovitrain, and dull humodurain. The s ample from the Lava deposit in the Servia Basin is composed of grayish to b lack, dark humoclarain. The predominance of humodetrinite macerals (densini te and attrinite) and the low contents of inertinite show that the lignites in the Ptolemais and Servia Basins are formed in limno-telmatic conditions and in different mire types, being similar to herbaceous swamp, fen, or ma rsh.