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The cross-polarized magic-angle-spinning NMR (CPMAS-NMR) technique was used in this work to assess the carbon distribution in coals of different rank (peat, lignite, xylite, sub-bituminous coal) from important deposits in Greece and Bulgaria. The technique is assumed to be only semiquantitative due to a number of interferences, such as spinning side bands (SSB) in the spectra, paramagnetic species in the samples, and low or remote protonation of aromatic carbons. The Bulgarian sub-bituminous coal shows the greatest amounts of aromatic structures. The lignite sample from the Drama basin Northern Greece, is relatively unaltered and largely unlettered, and shows the greatest amounts of aliphatic groups. The 13C-NMR spectra of Pliocene lignites from endemic areas in Serbia and Montenegro and Bosnia, taken from published papers, show significantly more intense resonance's for methoxyl phenolic, and polysaccharide moieties compared to the Drama lignite NMR spectrum. Xylite reveals high contents of carbohydrates.

The FTIR spectra for both Neogene xylite and matrix lignite samples from Achlada NW Greece show significant differences, which are mainly evident in aliphatic stretching region (3000-2800 cm-1) where the intensities of the vibrations are reduced in matrix lignite lithotype compared to xylite one. The intense bands in the region 3402-3416 cm-1 are attributed to -OH stretching of H2O and phenol groups. The bands at ~3697 cm-1 and ~3623 cm-1 as well as at ~538 cm-1 and 470 cm-1, which are more evident in the FTIR spectra of matrix lignite, are attributed to higher content of clay minerals in the samples of this lithotype. The stretching vibration appears at ~1032 cm-1 is intense in all matrix lignite samples and it is broadening in the xylite ones. The FTIR spectra of all samples confirm the progressive elimination of aliphatic vibrations from xylite lithotype to matrix lignite one and the appearance of clay minerals in the latter. As a whole the FTIR spectra of both xylite and matrix lignite confirm the significant differences between these two lignite lithotypes.

[EN] The concentrations of 47 trace elements In the Lava xylite/lignite and Ptolemais lignite deposits, as well as in their intermediate sterile bands, were determined by ICP-MS. The majority of the trace elements are depleted, as compared to Clarke's earth. Three elements (As, Se and Ag) are enriched in all samples. The stock pile samples of Lava are enriched in Ge, As, Se, Ag, Cd, Hg and U, while the stock pile samples of Ptolemais are enriched in B, As, Se, Ag and U. The majority of the elements are more or less, positively correlated with the ash content of the coal samples, while Mo and Hg are possibly negatively correlated. The elemental composition of the investigated samples is related to the nature of plant communities and to the geological conditions and processes of the basin and surrounding areas.

GRYC, V., SAKALA, J.: Identifi cation of fossil trunks from Bukkabrany newly installed in the Visitor Centre of the Ipolytarnoc Fossils Nature Reserve (Novohrad ‐ Nograd Geopark) in Northern Hungary. Acta univ. agric. et silvic. Mendel. Brun., 2010, LVIII, No. 5, pp. 117–122 The Late Miocene forest was discovered in the opencast lignite mine of Bukkabrany which is situated in the foothills of the Bukk Mountains (NE Hungary). Sixteen stumps were exposed upright in 2007 at their original position. Five stumps were installed in the Ipolytarnoc Fossils Nature Reserve. They are identifi ed in the present paper. The wood of one fossil trunk (No. 1) has been identifi ed as Glyptostroboxylon rudolphii, which represents the wood of Glyptostrobus. Its main microscopic features are: visible growth rings, gradual transition between early- and late wood, rather small opposite bordered pits in 1–2 loosely spaced vertical rows with infrequent crassulae, uniseriate rays formed of procumbent cells without ray tracheids, 1–3 “glyptostroboid” cross-fi eld pits per fi eld and resin canals absent. The four remaining stumps (Nos. 2–5) have been identifi ed as Taxodioxylon germanicum. Their main microscopic features are: growth rings, abrupt transition between early- and late wood, opposite bordered pits in 1–3 regular vertical rows with frequent crassulae, uniseriate rays formed of procumbent cells without ray tracheids, 1–3 taxodioid cross-fi eld pits per fi eld arranged mostly in one horizontal row, axial parenchyma both in early and late wood (diff use arrangement) with smooth transverse end walls and resin canals absent. This species most probably represents the wood of Sequoia.