The Ibar-basin, situated in the southwest of Serbia, contains several small coal basins of Tertiary age. The rank of the different coals was studied in the past and was determined again in this paper. Vitrinite reflectance ( R r ), fluorescence measurements of extracts and the liptinite maceral exsudatinite, as well as organic-geochemical investigations have shown a higher rank for the northernmost deposit of Usce (high volatile bituminous A coal) and lower rank in the deposits situated in the centre of the basin near Tadenje and in the south at Jarando, where the coal is of high volatile bituminous B/A rank. This relatively high rank for Tertiary coals is due to thermometamorphism. The petrography and geochemistry of Tadenje coal shows an extraordinary composition. This is explained by relatively enhanced oxidizing conditions during deposition. The low rank of the kerogen within the magnesite of Bela Stena in the south of the Ibar-Basin indicates that the magnesite deposition is younger than the peat accumulation. The magnesite is less affected by the andesite and dazite intrusions than the coal.

Hand-selected lithotypes of a Polish subbituminous coal were examined using organic-geochemical methods and microscopy. The random reflectance of the vitrinite was determined to be 0.52%. Chemical analysis of solvent extracts showed that in this rank region the intra-seam diffusion of bitumen present in the coal is of minor importance. Thus the lithotypes vitrain, durain and fusain each possess significant geochemical characteristics. The extract of the vitrain concentrate is enriched in degradation products of resinous material impregnating the whole vitrain. The fusain concentrate is characterized by a relatively high content of short-chain normal alkanes (C15-C20) and the main feature of the durain is its high pristane content. This indicates a distinct organic matter input or particular diagenetic conditions during coal lithotype formation.

Immature samples of the Permian Kupferschiefer from the Lower Rhine Basin in N.W. Germany were analysed for tetrapyrrole pigment type and abundance. The sediment, thought to have been deposited in a marine regime with enhanced salinity, was found to contain high concentrations of metalloporphyrins. The porphyrins are complexed to nickel (Ni) and oxovanadium (V=0), but high abundances of iron (Fe) porphyrins were also detected using UV/visible spectroscopy and mass spectrometry. The presence in the latter of series of aetioporphyrins, cycloalkanoporphyrins, di-cycloalkanoporphyrins and benz-cycloalkanoporphyrins was confirmed by accurate mass measurements; HPLC co-injection of deoxophylloerythroetioporphyrin (C32 DPEP) with the demetallated iron porphyrins indicated its presence in the sediment as an iron complex. The study provides the first evidence for the occurrence of Fe porphyrins in geological samples other than coals and lignites, and reports the highest concentrations in sedimentary organic matter to date.

According to previous studies, there is a significant difference in the thickness and number of coal seams from the foredeep and the intermontane coal basins (or basins situated on platforms and cratons). Recent petrographic and geochemical investigations on selected coal samples from foredeep and intermontane basins of Europe (Carboniferous and Tertiary) and South America (Permian) show that the coal seams in each of these coal basins have significant differences in their petrographic and geochemical compositions. Many intermontane coals are characterized by more liptinite than foredeep coals. Fluorescence studies show that up to 75% of the liptinite macerals of these humic coals can be attributed to alginite and/or degradation products of algae. This indicates that generally subaquatic conditions occurred more often in the peats that formed within intermontane basins.

The Kupferschiefer of the Lower Rhine Basin and of NW Germany is a typical black shale containing Corg values between 0.5 and 9.1%. On average it contains 4% Corg.

A series of eight Tertiary coal and carbonaceous shale samples with vitrinite reflectance values between 0.50 and 0.58% were extracted, fractionated and the saturated and aromatic hydrocarbons analysed for characteristic components by GC and GC-MS. Additionally, a microscopical study was undertaken in order to obtain a more precise picture of the samples under investigation.

According to previous studies alginite does not occur in humic coals. However, in coals from the Saar District, F.R. Germany, alginite was identified by fluorescencemicroscopy. In addition, high amounts of an undeterminable liptinite maceral were found and tentatively explained as an alteration product of alginite. Therefore, organic geochemical methods were used to characterize and identify this unknown liptinite maceral.