Chemical properties and petrographic composition of the lacustrine Seyitomer lignites (Miocene), Kutahya, Turkey

The Seyitomer basin, which is one of the most productive coal basins of western Anatolia-Turkey, contains two seams, lower and upper in the Lower-Middle Miocene lacustrine Seyitomer Formation. The lower seam in this basin is only extensively exploited by open-cast methods and produced lignites are mainly consumed in coal-fired power plants. A total of thirty-six lignite samples, of which thirty-one are from the lower seam and five from the upper seam, were collected from the two locations (DK and S30), and have been subjected to chemical and petrographic analyses. The chemical analyses of the coal ash samples with XRF show that the lignite samples on a whole-coal basis are enriched for Cr and especially Ni, and Bi, Co, Cu, Mo, Sc and V and also exceed the range values of the most world coals. The most abundant maceral group of all the samples is huminite, in which textinite, ulminite and especially densinite are rich. Liptinite group macerals in all the samples, which are considerably higher than the inertinite group macerals, include mainly sporinite and liptodetrinite. The mean values of maximum reflectance (av. 0.29%) in oil of ulminite from the lignite samples in the Seyitomer Basin show a lignite stage (soft brown coal) in rank. In addition, vertical variations of some results in the two lignite seams have been also considered in this study.