Organic geochemical characteristics of the Upper Cretaceous-Early Paleogene source rock and correlation with some Egyptian mummy bitumen and oil from the southern Gulf of Suez, Egypt

摘要

Previous research has focused upon the geochemical fingerprinting of oil and mummy bitumen in order to define their biomarker characteristics and their geographical origins. Here, a set of source rock samples comprising the Upper Cretaceous-Early Paleogene sequence from the Ras El Bahar-2 borehole on the western coast of the southern Gulf of Suez is investigated for a comparative molecular biomarker link between source rock bitumen and oil and mummy bitumen. The analysed source rocks are quantitatively rich in organic content and qualitatively derived from algae and bacteria deposited in highly reducing environments. The source rocks are sulphur-rich and related to type II-S kerogen, having the ability to generate hydrocarbons at low levels of thermal maturity. For oil and seeps, they are genetically related. The biomarkers suggest their derivation from siliciclastic source rocks that received substantial terrestrial inputs within predominantly Tertiary basins and were deposited in normal marine conditions with pervasive suboxia. The source rock bitumen is correlatable with the Cleopatra mummy bitumen, whereas the oil seeps are comparable with the bitumen from some Egyptian mummies reported in the literature.