MOLECULAR COMPOSITION OF A LEAF-BEARING AND ROOT-BEARING OLIGOCENE OXBOW LAKE CLAY IN THE WEISSELSTER BASIN, GERMANY

A plant fossil bearing clay profile from the Upper Oligocene Thierbach strata (Weisselster Basin, Germany) has been sectioned into horizons and the plant macrofossils of each section surface have been identifie d by morphological and anatomical studies. In the upper half of the pr ofile leaves from Populus germanica and Carpinus grandis and branchlet s from the conifer Taxodium balticum vel T. dubium dominate the horizo ns while the lower part contains only root remains of unknown higher p lants. In the Soxhlet-extracted samples from each section n-alkanes, n -alkanols, n-carboxylic acids, and several terpenoids [beta-amyrin, 24 ,25-dinoroleana-1,3,5(10),12-tetraene, olean-12-en-3-one, simonellite, and hop-17(21)-ene] were identified by combined gas chromatography-ma ss spectrometry. The comparison of the extracted chemical compounds an d the macrofossil record of the profile shows that simonellite occurs preferentially in the Taxodium bearing horizons, n-Alkanes, n-alkanols , n-carboxylic acids, and beta-amyrin were found in all sections, but are enriched in the root-containing part of the profile. The distribut ion of hop-17(21)-ene is independent of the input of higher plant rema ins.