Abstract
The molecular markers (n-alkanes, dibenzothiophene, phenanthrene, methyldibenzothiophene, and methylphenanthrene) have been determined in eight oil samples from different Egyptian oil fields. These parameters are used together to provide information on source organic matter input, depositional environment, and the maturity of crude oils. The results showed that the crude oil samples are classified into moderately mature oil, which includes Yidma-6, N. Ras Qattara-3, Alamein-1, and Ghana-1 wells, generated from mixed organic sources in reducing environment, characterized by low wax content, and low to moderate sulfur content. Mature oils are generated from source rocks deposited in lacustrine palaeoenvironmental conditions and include oils from IF 37-1, Balayim Land, E. Wadi Araba-3, and NDR wells characterized by high wax and high sulfur contents. Therefore, it is recommended that the molecular and polycyclic aromatic sulfur compounds play an important and powerful role in characterization and evaluation of crude oils.