Contribution to Petroleum Source Rocks and Thermal Maturation of
Jurassic-Cretaceous, S. Matrouh, N. Western Desert, Egypt
Lobna M. Sharaf, Mohamed F. Ghanem1;
Samir A. Hussein and
Mohamed El Nady1
Geol. Dept., Fac. Sciences, Ain Shams Univ.,Egypt; 1Egyptian
Petroleum Research Institutef,
Cairo, Egypt |
In the search for hydrocarbons, the geochemical analyses (pyrolysis, maturity indicator
(Ro%),
and gas chromatograms of saturated hydrocarbons), in addition to burial history models of
the drilled Jurassic-Cretaceons sections in some wells suggest the following : Ras Qattara
Fm
(Early-Mid Jurassic) bears a mature source rock with poor capability for generating gas,
formed
under slightly oxic depositional environment. Khatatba Fm (Mid Jurassic) bears mature
source
rock with poor to good capability for generating mixed oil and gas of mixed organic
sources. It
reached peak of oil generation since the Cretaceous. Masajid Fm (Late Jurassic) bears
mature
source rock with poor potential for generating gas, and mixed organic sources, deposited
under
oxic environment. It entered the oil window in times varying from Late Cretaceous to
Eocene.
Alam ElBueib (Barremian-Early Aptian), Kharita (Early Albian), and Bahariya (Late
Albian-Early
Cenomanian) Fms and Abu Roash "G" Memer (Late Cenomanian) are similar in their
source
potential (poor to fair), in type of contained kerogen (mixed oil and gas-prone); all were
deposited
under slightly oxic environment, except Abu Roash "G" Member which was deposited
under slightly
reducing environment. Alam ElBueib Fm entered the oil window in times varying from Late
Cretaceous to Late Eocene. At present, Khatatba, Masajid, and Alam ElBueib Fms in some
wells,
are still within the oil window while Kharita Fm is immature to marginally mature lying
within the early
stage of generation in most of the drilled sections. Bahariya Fm and Abu Roash
"G" Member are
still immature in all the drilled sections. In conclusion, Khatatba, Alam ElBueib, and
Kharita Fms
are effective source rocks in the study area. Khatatba Fm is the main source for
hydrocarbon
accumulations in this area followed by Alam ElBueib, and Kharita Fms. Bahariya Fm and
Abu Roash "G" Member are considered as potential source rocks, in the drilled
sections for
generating hydrocarbon at optimum maturity.
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