Aromatic Biomarkers as a Tool to Identification a Source and Palaeodepositional of Sajau Coal, Berau Basin, Indonesia

The distributions and concentrations of plant-derived aromatic biomarkers were investigated in the Pliocene coal seam from Pliocene Sajau Formation in Berau Basin, Indonesia. The study aims to identify vegetational sources and ancient depositional of these coals. The distribution of aromatic hydrocarbons were detected, including 1,2,7-Trimethylnaphthalene (TMN), 1,6,7-TMN, and 1,2,5-TMN, cadalene, retene,1-methylphenanthrene (MP), 3-MP, 9-MP, 1, 2,-dimethylphenanthrene (DMP), 2,6-DMP, 2, 7-DMP, 1.3. 8 Trimethyl Phenanthrene (TMP) and polycyclic aromatic hydrocarbons (PAHs). The distribution of aromatic biomarkers indicated that in the Lower part of Sajau Coal were relatively dominated gymnosperms, while in the middle and upper part of Sajau Coal, an angiosperm dominated higher plant and conifers. The coals showed mainly charred indicated by abundances of combustionderived PAHs such as Benzo[a] anthracene, fluoranthene, and benzofluoranthene in coals indicated the coals. The deltaic depositional environment is the place for forming Sajau Formation coal