الفهرس 
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Abstract
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CHAPTER JX
SUMMARY and CONCLUSION
This part of the thesis summarizes the steps followed in this study and indicates
the salient results of the study.
SUMMARY:
The present work deals with the stratigraphy of the Upper Cretaceous-Lower
Tertiary succession in an area located between Wadi Tayiba and Wadi Feiran in
west central Sinai. Two sections were measured in the study area, Mouth Feiran
and Mouth Withr sections.
This study includes the following parts:
1- A discussion of the previous literature on the Late Cretaceous, Paleocene
and Eocene of Egypt in general and of Sinai in particular.
2- A discussion of the lithostratigraphic units and their relation to time
stratigraphic units •
• In this part of the thesis, it intended to provide a good understanding of the
different stratigraphic units and correlate with the rock unit recognized in
other parts of Egypt, especially the Nile Valley.
3. A discussion of the biostratigraphic subdivisions based on both Planktonic
foraminifera and larger benthonic foraminifera (Nummulites) for each section
in addition to correlation with the standard universal biozones recognized
in other parts of the world.
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4- A detailed description of the measured and sampled stratigraphic sections.
This description involves the megascopic characters of the various beds as
recognized in the field as well as a list of all foraminifera and megafossils
in each bed. This part is also illustrated by some stratigraphic paleontologic
charts for the measured sections, in addition to a geologic map showing the
location of the two studied sections.
5- A taxonomic <’ftscussionof the identified foraminiferal (Planktonic and larger
benthonic) species including some remarks of each species, and its stratigraphic
distribution in the world and in the study area. The identified foraminiferal
species are illustrated by (12) plates. Furthe.!JIWre, some range charts
for the identified foraminiferal species for each section have been drawn.
6- A discussion of the age assignment (chronostratigraphy) for the different
biozones using the planktonic and larger benthonic foraminifera in order to
throw some light on the Cretaceous-Tertiary boundary.
7- A discussion of the geologic history of the study area during the Late Cretaceous
and Early Tertiary. This history includes the various sedimentary
cycles and the paleoenvironmental conditions prevailed during the deposition
of the studied rock units, in addition to the tectonic frameWork of the Gulf
of Suez and its relation to the Red Sea tectonism.
CONCLUSIONS:
1- Seven lithostratigraphic units would be recognized, these are arranged from
base to top as follows: Sudr Chalk, Esna Shale, Thebes Formation, Darat
Formation, Khaboba Formation, Tanka Formation and Red Beds.
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Sudr Chalk (GHORAB, 1961) is composed of chalky limestone that grades
into argillaceous limestone; Esna Shale (BEADNELL, 1905) consists of
greenish grey shales and marls; Thebes Formation (SAID, 1960) is composed
of bedded limestone, chalky in parts and intercalated with chert bands and
concretions; Darat Formation (VIOTTIand EL DEMERDASH, 1968) is composed
of alternating green and brown shale and marls with brownish limestone;
Khaboba Formation (VIOTTI and EL DEMERDASH, 1986) is delimited in its
lower part by’ a gypsiferous shale bed while the upper boundary is delimited
by a chalky limestone bed with some pelecypod casts’; Tanka Formation
(HUME et al., 1920) is composed of thin intercalations of chalky limestone
and yellow claystone beds. The presence of Red Beds overlying the Tanka
Formation reflects unconformable relationship.
It is worthy to mention that the facies of the top part of Darat Formation
and probably the overlying Formations (Khaboba and Tanka) in the northern
part of the study area vary laterally into purely Nummulitic Limestone facies
towards the southern part. Also it is worthy to mention that the Nummulitic
Limestone fac~~s is equivalent to the Qarara Formation in the Nile Valley
facies depending on the identified Nummulites species.
2- As a result of the distribution of the identified species, 17 planktonic
foraminiferal biozones were recognized including one benthonic Iarger
foraminiferal biozone. These are arranged from base to top as follows:
Globotl”uncane aegyptiaca zone and Gansserina gansseri zone (Maastrtchtian);
Morozovella pseudobulloides and Morozovella tl”inidadensis zones (Early
Paleocene); Morozovella uncinata, Morozovella angulata and Planorotalites
pusilla pusilla zones (Middle Paleocene); Planol”otalites pseudomenardii and
Morozovella velascoensis zones (Late Paleocene); MOl”ozQvellasubbotinae,
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Morozovella formosa formosa; Morozovella aragonensis, Acarinina pentacamerata
zones (Early Eocene); Hantkenina naHulli, Globigerinatheka subconglobata
sUbconglobata, Morozovella lehneri, Truncorotaloides rohri and
Nummulites gizehensis (s.L) zones (Middle Eocene).
The previously mentioned planktonic foraminiferal zones were matched with
their equivalents universally and in Egypt.
3- Eighty six planktonic species and one larger benthonic species of foraminifera
of Upper Cretaceous-Lower Tertiary succession (belonging to 24 genus) are
identified.
4- from the study of chronostratigraphy of the studied sequence plays a great
role in establishing the following ages: Maastrichtian (Sudr Chalk), Paleocne-
Early Eocene (Esna Shale), Early-Middle Eocene (Thebes, Darat, Khaboba,
Tanka and Qarara Formations).
The relation between the Maastrichtian and Paleocene is unconformable
while the relation between the Paleocene and Eocene is conformable. The
magnitude of the unconformity between the Late Cretaceous and Early
Tertiary is larger in Mouth Withr section than in Mouth Feiran section. There
is a gap in the faunal fossil content in Mouth Withr section whereas the last
zone of Middle Paleocene (Planorotaloites pusilla pusilla zone) is missing.
Therefore, the lacunae of sedimentation in the two studied sections reflect
the instability of the region during the Late Cretaceous-Early Tertiary time.
5- The boundary between MaastriChtian and Paleocene is delineated by the
appearance of i!0rozovella pseudobulloides zone Which represents the lower
part of Early Paleocene.
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The boundary between Paleocene and Early Eocene is delineated by the
appearance of Morozovella subbotinae zone which represents the lower part
of Early Eocene, while the boundary between the Early Eocene and Middle
Eocene is delineated by the appearance of Hantkenina nuttalli zone which
represents the lower part of Middle Eocene. The boundary between the
Middle Eocene and Late Eocene is not clearly identified biostratigraph ically,
but it is defined lithologically, where the Red Beds overlie the Tanka Formaticn,
6- The field observations and the micropaleontologic studies reflected the
change in bathymetry of the sedimentary basins during the deposition of the
Late Cretaceous and Early Tertiary successions of west central Sinai.
Three sedimentary cycles are recognized in the study area. The first sedimentary
cycle includes the measured part of the Sudr Chalk Formation and
the lower part of the Esna Shale, the transgressive part of this cycle started
at the beginning of the Senonian and the acme of the cycle is the Sudr Chalk
¢!
(Which is represented by the two zones, Globotruncana aegyptiaca and
Gansserina gansseri), The regressive part of this cycle is represented by a
lacuna of sedimentation in the uppermost Maastrichtian and the lowermost
Paleocene sediments, where two biozones are missing (.\bathomphalus mayaroensis
and Globigerina eugubina).
The second sedimentary cycle includes the upper part of the Esna Shale and
Thebes Formation, the transgressive part of this cycle is represented by two
biozones of the Middle Paleocene (Morozovella uncinata and Morozovella
angulata) and its acme is marked by the Late Paleocene. The regressive
part is represented by the Thebes Formation. The third sedimentary cycle
includes the Darat, Khaboba and Tanka Formations, the transgressive part of
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the cycle is represented by the Darat Formation and its acme is the Khaboba
Formation. The regressive part of this cycle is marked by the Tanka Formation,
The Middle Eocene Formations (Darat, Khaboba and Tanka) are re- • presented by open deep marine facies, whereas they are including deep planktonic
facies in the northern part of the study area at Mouth Feiran section,
While in the southern part at Mouth Withr section, similar horizons are represented
by benthonic larger foraminifera mainly Nummulites gizehensis
(FORSKAL) s.l, which indicates shallow marine conditions.