الفهرس 
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Abstract
The Abu Qir area lies in the northwestern side of the Nile Delta region,
the offshore Mediterranean Sea, between longitudes 30° 00´- 30° 24´E and
latitudes 31° 18´- 31° 40´N.
The Nile Delta is one of the most promising provinces in Egypt due to
its significant hydrocarbon potential. The Abu Qir basin is considered as one
of three main sub-basins in the Nile Delta that has been formed due to the
effect of the Serravalian tectonic movement during the Late Miocene. Patterns
of sedimentation in the northern delta between the late Oligocene and the
Pliocene were controlled by four reactivated faults named the Bardawil line,
Qattara-Eratosthenes line, Pelusium line, and Hinge zone.
The sedimentary sequence penetrated by wells in the study area
consists of thick Miocene-Pleistocene siliciclastics. The lithostratigraphy of
the study area is represented by Miocene sediments (Qantara, Sidi Salem, and
Abu Madi formations) and the Pliocene–Pleistocene sequences (Kafr El
Sheikh, El Wastani, and Mit Ghamr formations), which are represented mainly
by shale or clay with sandstone interbeds. Also, Qantara Formation (Early
Miocene) is composed of calcareous marine shales and sandstones. In
addition, the formation is overlain unconformably by the Sidi Salem
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Summary and Conclusions
Formation (Middle Miocene) which is dominated by shales with some
sandstones facies, deposited under marine to fluvial condition. Moreover, it is
unconformably overlain by Qawasim and/or Abu Madi formations. Moreover,
these formations are overlain unconformably by Kafr El Sheikh Formation,
which is composed of shales and sandstones. In addition, the thickness of the
Kafr El Sheikh Formation increases towards offshore areas. Furthermore, Kafr
El Sheikh Formation is overlain by El Wastani Formation (claystones and
sandstones), which represent a transitional facies between the shelf facies of
the Kafr El Sheikh Formation and the fluvio-deltaic facies of the overlying Mit
Ghamr Formation.
The purpose of this study is to evaluate the possible source rocks in
Abu Qir fields, through several geochemical analyses and predicting the
maturation levels reached by the source rocks and the time of hydrocarbon
generation. Additional objectives are to characterize the condensates
recovered from Kafr El Sheikh and Abu Madi reservoirs from the same fields
using biomarker analyses, and to identify the origin of the natural gas in this
area on the basis of geochemical and stable isotope data.
The geochemical analyses (total organic carbon analyses, Rock Eval
pyrolysis and vitrinite reflectance measurements) of one hundred and sixty-
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Summary and Conclusions
two (162) cuttings samples of the Kafr El Sheikh, Sidi Salim and Qantara
formations from North Abu Qir-1 (NAF-1), North Abu Qir-101 (NAF-101),
West Abu Qir-1X (WAQ-1X) and West Abu Qir-4X (WAQ-4X) wells in Abu
Qir concession suggest the following:-
1- Kafr El Sheikh Formation is immature to marginally mature rocks
source rock in the drilled sections, with poor to fair generating potential to
generate mainly gas.
2- Sidi Salim Formation has poor generating potential to generate
mainly gas in the drilled sections. This formation is marginally mature in
NAF-1 and NAF-101 wells and entered the oil window in NAF-1 and WAQ-
1X wells.
3- Qantara Formation is penetrated only in NAF-101 well and is
considered to be immature to marginally mature rock with poor generating
potential to generate gas.
Four condensate samples from the studied wells were analyzed using
whole-oil gas chromatography (GC), medium pressure liquid chromatography
(MPLC), carbon isotopic analysis, and gas chromatography-mass
spectrometry analysis (GC-MS) on the saturate and aromatic fractions. In
addition, four gas samples were collected from the previous wells and
analyzed for methane (C1), ethane (C2), ethylene (C2H4), propane (C3),
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Summary and Conclusions
propylene (C3H6), butanes (i-C4and n-C4), pentanes (i-C5and n-C5), C6+ and
non-hydrocarbons composition and δ13C isotopic analysis of methane, ethane,
propane, and CO2. Also, be aware that the gases were recovered from the
same reservoirs as the condensates. The geochemical analyses were conducted
through Stratochem Laboratories and provided by Abu Qir Petroleum
Company.
The geochemical characterization of four condensate samples suggest
their derivation from clay-rich source rocks with mixed organic sources
deposited under oxic to suboxic low salinity conditions, suggesting a
transitional environment. The abundance of both C27 and C29steranes indicate
both terrestrial and marine influence. However, the presence of moretane and
the richness of 6RP indicate a more significant contribution from terrestrial
organic matter. In addition, the presence of oleanane (albeit in low
concentration) may imply Late Cretaceous-Early Tertiary age for the
condensate source rocks. Moreover, the maturity indicator ratios indicated that
Abu Qir condensates were generated during the early stage of source rock
maturation.
Molecular and isotopic composition for the analyzed gases from the
AQ Concessions suggests that the studied gases are of thermogenic origin and
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Summary and Conclusions
are dominated by mixed type II/III kerogen. Finally, the different maturity
ranges for the studied gases may be attributed to the mixed kerogen Types (II
and III) of the studied gases.
One-dimensional modelling of burial history and thermal maturity was
constructed for the wells NAF-1, NAF-101, WAQ-1 and WAQ-4 and
suggested that all the wells show the same geological settings, which is
characterized by the presence of three main sedimentation phases (periods)
separated by Hiatus or uplift events. The most rapid and main burial phase
starts by the end of the Pliocene and continues to present day. Although the
study wells have the same geology but the preserved thicknesses show slight
differences from well to another.
Cumulative Hydrocarbon Curves were constructed for the four
investigated source rocks (Kafr El Sheikh, Sidi Salim, Qantara and Tineh
formations) suggesting that the Kafr El Sheikh source rocks in the drilled
sections are currently immature to marginally mature and only minor
hydrocarbon generation could be expected, while no hydrocarbon expulsion
have been taken place, however the Sidi Salim source rocks are generated
higher amounts relative to that obtained from the Kafr El Sheikh source rocks
but also no expelled hydrocarbons had been taken place. In addition, the
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Summary and Conclusions
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Qantara source rocks reflect that there is noticeable hydrocarbon generation
has occurred. Although the generated hydrocarbons from Qantara Formation
appear significant and much greater than those appeared from the shallower
source rocks (Kafr El Sheikh and Sidi Salim) but it does not overcome the
saturation threshold (20%) of the source rock and therefore no hydrocarbons
expulsion could have been take place. The cumulative hydrocarbon curves of
the Tineh source rock (Oligocene) suggest that it reaches its capacity for
hydrocarbon expulsions in all the studied wells and it is in early or mid of the
wet gas/condensate maturity stages. The oil expulsion from Tineh source rock
started during the Pleistocene and continued to recent with total expelled oils
ranged between 26 bbls/acre-ft to 31 bbls/acre-ft and total expelled gas of
about 42-89 ft^3/acre-ft of gases (hypothetical numbers).