An Organic Geochemical Characterization of Crude Oils from El Hamd and Bakr Oilfields in the Gulf of Suez, Egypt

Abstract

Seven crude oil samples were collected from wells of the El Hamd and Bakr oil fields located in the central Gulf of Suez and their chemical composition, API gravity, sulfur content, and asphaltene content were determined. Nickel and vanadium contents were measured using atomic absorption spectroscopy. Saturated paraffinic hydrocarbon fractions were subjected to gas chromatography in order to investigate carbon number distribution. Terpanes and steranes biomarker distributions have been determined using gas chromatography-mass spectroscopy in order to characterize the type of organo-facies, oil classes, depositional environments of the studied crude oils, and to assess the thermal maturity level for oil generation. It has been found that mature oils are generated from marine shales and carbonates are enriched in marine algae with a contribution from terrestrial organic matters.

Keywords:

• API gravity
• Egypt
• Gulf of Suez
• nickel and vanadium
• oilfields
• sulfur content
• terpanes and steranes biomarkers

Notes

^a5α(H),14α(H),17α(H)-20R-steranes.

^b24-Ethyl-13β*(H),17α(H)-diacholestane(20R)/24-Ethyl-5α(H),17α(H)-cholestane(20R).

^cC₃₅17α(H),21β*(H)30Pentahomohopane(225+22R)ΣC₃₁toC3517α(H),21β*(H)30homohopanes (22S+22R).

^d18α(H)22,29,30Trinorneohopane/17α(H)22,29,30trinorhopane.

^e18α(H)Oleanane/C₃₀17α(H),21β*(H)hopanepH₃₁:C₃₁17α(H),21β*(H)30homohopane(225), H32:C₃₂17α(H),21β*(H)bishomohopane(225).

^f17α(H),21β*(H)-30-norhopane/17α(H),21β*(H)-hopane.

^gC₃₀17β*(H),21α(H)-hopane/C₃₀17α(H),21β*(H)-hopane.

^hSteranes maturity level.