Biostratigraphy and palaeoenvironmental in ter pre ta tion of the Dalichai Forma tion (Lower Cre ta ceous) in the east ern and cen tral Alborz Moun tains (North Iran) based on cal car e ous nannofossils. Geolog i cal Quar terly, 64 (3): 641-657,

Biomarkers are very useful tools for paleontologists, especially where the undistinguishable organic matters like Tabriz lignite cannot be attributed to particular fossils. In this study, the important detected biomarkers in Tabriz lignite beds are Oleananes (Olean-12ene and Friedelane), beta carotene, Dibenzofuran and Gibberellic acid. The results indicate angiosperm higher and lower plants entering from adjacent areas into the lake sedimentary environment of the lignite beds. No biomarker of gymnosperm was found. The short chain even n-alkanes (C18 and C20) imply the contribution of marine microorganisms, C23 normal alkane is derived from terrestrial plants specially Sphagnum leaf wax, the existing simple methyl saturated alkanes (C11-C22) is derived from cyanobacteria and algae and thiophene formed by sulfate reducing bacteria. Thus, Tabriz lignite have two extrabasinal and intrabasinal origins that the first is made of the higher (angiosperms) and lower terrestrial plants have transported by runoffs into the basin and the second origin is made of seagrasses, cyanobacteria and algae within the lignite beds basin.

No abstract