Geochemical Comparison of Ilam and Sarvak oils in Marun and Kupal oilfields based on their physical and chemical properties of studied samples

Marun and Kupal oilfields situated in south east of Ahwaz city next to Agha Jari and Ahvaz oilfields are among the largest oilfields in the Dezful Embayment. Ilam and Sarvak formations constitute the main reservoirs. In order to investigate geochemical characteristics, oil samples of Ilam and Sarvak reservoirs studied by analyzing their physical and chemical properties. Investigation based on physical properties including sulfur content (%), nickel to vanadium ratio, API gravity and other physical properties suggest similar maturities for the oil samples. Biomarkers study of extracted Terpanes and Steranes of saturate section reveals that accumulated hydrocarbons in understudy reservoirs were originated from carbonate source rock. The kerogen of source rocks is possibly type II or mixed of type II and III. Biomarker investigation also detected that the candidate source rock(s) are thermally mature. Studying of Oleanane index reveals that oils in Marun and Kupal oilfields were originated from marine organic matter. It also shows a pre-Cretaceous source rock(s).