Nubia sandstone aquifer in Egypt, origin and distribution

1. Nubia sandstone
By
Abd Al Rahman Ibrahim Soliman,
BSc of Geoscience ,
Faculty of science, Alexandria University.
abdalrahmanibrahim209@gmail.com

2. 2
Introduction
Nubia sandstone
 Introduction
 Problem of Nubia sandstone
 Origin of Nubia sandstone
 Stratigraphy of Nubia sandstone
 Mechanical analysis of Nubia
sandstone
 Mineral analysis of Nubia sandstone
 References

3. 3
Introduction
Nubia sandstone
The term Nubia Sandstone is well
established in the stratigraphic column of
Egypt and is used to describe the
extensive sandy formations (clastic
series) either overlying the Precambrian
basement rocks or conformably
underlying the marine sequence of Upper
Cretaceous variegated shale.

4. 4
Introduction
Nubia sandstone

5. 5
Problem of Nubia sandstone
Nubia Sandstone
The fact that it covers vast areas in Egypt
with a broad age window ranging from
Early Paleozoic to Late Cretaceous due to
lack of any credible record of index body
fossils has always caused a problem of
where to consider it in the Egyptian
geochronological sequence.

6. 6
Problem of Nubia sandstone
Nubia Sandstone
The fact that it covers vast areas in Egypt
with a broad age window ranging from
Early Paleozoic to Late Cretaceous due to
lack of any credible record of index body
fossils has always caused a problem of
where to consider it in the Egyptian
geochronological sequence.

7. 7
Problem of Nubia sandstone
Nubia Sandstone
The fact that it covers vast areas in Egypt
with a broad age window ranging from
Early Paleozoic to Late Cretaceous due to
lack of any credible record of index body
fossils has always caused a problem of
where to consider it in the Egyptian
geochronological sequence.

8. 8
Why interest in Nubia Sandstone

9. 9
Why interest in Nubia Sandstone
Nubia Sandstone
In spite of the Nubian sandstones is
considered as the main reservoir of giant
oil fields in Egypt especially in Gulf of
Suez region, the Nubian sandstones also
represent the main water aquifer in Egypt
especially in western desert.

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Why interest in Nubia Sandstone
Nubia Sandstone
In many localities especially in Sinai the
Nubian sandstone intercalated with
kaolinitic deposits which are of potential
economic importance. The Nubian
sandstones are the main source of glass
sand in Egypt.

11. 11
Introduction
Groundwater Drilling techniques
 Origin of Nubia sandstone
 Stratigraphy of Nubia sandstone
 Mechanical analysis of Nubia
sandstone
 Mineral analysis of Nubia sandstone
 References

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Origin of Nubia sandstone
Nubia Sandstone
Evidences Much has been written about
the origin of the Nubian Sandstone in
Sudan and Egypt. Aeolian, deltaic,
estuarine, and marine depositional
conditions have been advocated by
different authors

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Origin of Nubia sandstone
Nubia Sandstone
Evidences Much has been written about
the origin of the Nubian Sandstone in
Sudan and Egypt. Aeolian, deltaic,
estuarine, and marine depositional
conditions have been advocated by
different authors

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Origin of Nubia sandstone
Nubia Sandstone
 Walther (1888) and Fortau (1902)
considered that the Nubian Sandstone
was deposited along the southern
margin of the Paleozoic and Mesozoic
Tethys as a gigantic desert deposit.
 Barthoux (1922), Cuvillier (1930), and
Picard (1943) also accepted an aeolian
origin. However

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Origin of Nubia sandstone
Nubia Sandstone
 Hume (1906) favored a marine and
Mesozoic Tethys as a gigantic desert
However, Hume (1906) favored a marine

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Origin of Nubia sandstone
Nubia Sandstone
 Hume considered the Nubia sandstone
to be of marine origin because
 The flat regular nature of the base on which the Nubia
sandstone resets
 The presence of gravel cautes, conglomerate in same
parts.
 The extreme randomly quartz pebbles.
 The un broken passage into marls containing marine
fauna of definite age, and
 The occurrence through very rarely, in the Nubia

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Origin of Nubia sandstone
Nubia Sandstone
A. J. WHITEMAN' Ibadan, Nigeria origin,
basing his conclusion on presence of
 rounded boulders in the basal conglomerates,
 the transition with sandstones containing
marine fossils,
 and on his considerable field knowledge of the
geology of Egypt and the riverain Sudan,
 Ball (1907) thought that the Nubian
Sandstone in the Aswan area of
Egypt indicated shallow-water deposition.

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Origin of Nubia sandstone
Nubia Sandstone
Barron considered the Nubia sandstone
of Sinai to be of fluvio – marine origin as
it is
 well stratified and
 the clay and marly beds are interbedded
with the sandstone.

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Origin of Nubia sandstone
Nubia Sandstone
El Askary, El Mahdy studied the Jurassic
succession of the kharga coal
prospecting well No. 1. They showed that
 an alternation of sandstones,
siltstones, sandy, silty, clays
and clays. Each of these rocks exhibit
different lithologic verities which
grade into each other.
Numerous coal fragments where

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Origin of Nubia sandstone
Nubia Sandstone
Based on geochemical studies of
trace elements shown in following
diagrams(Fig. it seems that most of
the analyzed samples belong to
fresh water environment while few are
either brackish or marine.
 The presence of conglomerate
together with entire absence of
marine fauna and flora in the situ.

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Origin of Nubia sandstone
Nubia Sandstone
Relative
abundance of B,
Ga, and Rb in the
raw clays and
separated clay
fraction of the
Nubia
sandstone of
Kharga oasis.
(Dividing lines
after Degens et.
Al. 1957). O =

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Origin of Nubia sandstone
Nubia Sandstone
Samples are Favor of fresh to
brackish water environment of deep
this origin was assumed by El
Ghazaly based on paleontological
study of the same succession.

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Origin of Nubia sandstone
Nubia Sandstone
Relation between
B and Ga in the
raw clays and
separated clay
fraction of the
Nubia sandstone
of Kharga
oasis. (Divivding
lines after Degens
et. Al. 1957). O =
raw clays; +=
separated clays

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Origin of Nubia sandstone
Nubia Sandstone
Based on these geochemical diagrams,
El-Askary also showed that at wadi
kalalsha (SW of Aswan ) the Nubia
sandstone succession (upper
cretaceous) which enclose
irregularly shaped kaolinite lenses was
deposited in fresh water environment.

25. 25
Introduction
Nubia Sandstone
 Stratigraphy of Nubia sandstone
 Mechanical analysis of Nubia
sandstone
 Mineral analysis of Nubia sandstone
 References

26. 26
Stratigraphy of Nubia Sandstone
Nubia Sandstone

27. 27
Stratigraphy of Nubia Sandstone
Nubia Sandstone
Nubia Formation" as used herein refers
to the predominantly non marine
terrigenous sequence overlying
Precambrian basement and underlying
Upper Cretaceous marine shale and
limestone.
The age of the Nubia Formation in the
central Eastern Desert generally is
thought to be Late Cretaceous.

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Stratigraphy of Nubia Sandstone
Nubia Sandstone
The lowermost sandstones, which
contain only undated plant fragments,
may be older.
A few bivalves reportedly of
Cenomanian age are present about 50 m
above the base of the Nubia near Aswan.
Beds we include in the upper Nubia
interfinger northward with
deposits containing Campanian fossils.

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Stratigraphy of Nubia Sandstone
Nubia Sandstone

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Stratigraphy of Nubia Sandstone
Nubia Sandstone
The overlying Duwi Formation is dated
as Campanian (e.g., Ghanem et al, 1970),
or Maastrichtian (e.g., Issawi, 1972), or
Campanian-Maastrichtian (e.g.. Said,
1962).
West of the Red Sea Mountains the
basal Nubia crops out in a fringe around
exposures of the Precambrian basement
complex, and progressively younger

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Stratigraphy of Nubia Sandstone
Nubia Sandstone
On the eastern side of the mountains the
Nubia Formation crops out only in the
Safaga-Quseir area, where the section is
exposed in fault blocks

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Stratigraphy of Nubia Sandstone
Nubia Sandstone

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Stratigraphy of Nubia Sandstone
Nubia Sandstone

34. 34
Introduction
Nubia Sandstone
 Mechanical analysis of Nubia
sandstone
 Mineral analysis of Nubia sandstone
 References

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Mechanical analysis of Nubia sandstone
Nubia Sandstone
The lower half of the Nubia in the
Eastern Desert is predominantly
sandstone and
conglomeratic sandstone, and the upper
half is mostly fine sandstone, siltstone,
and shale

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Mechanical analysis of Nubia sandstone
Nubia Sandstone
The section can be divided into five major
lithologic units, in ascending order:
1. A basal unit of trough-cross-bedded sandstone
and conglomerate with non-bedded kaolinitic
sandstone;

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Mechanical analysis of Nubia sandstone
Nubia Sandstone

38. 38
Mechanical analysis of Nubia sandstone
Nubia Sandstone
The section can be divided into five major
lithologic units, in ascending order:
1. A basal unit of trough-cross-bedded sandstone
and conglomerate with non-bedded kaolinitic
sandstone;
2. gray and red shale and thin, sparsely
fossiliferous sandstone (Aswan area only);

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Mechanical analysis of Nubia sandstone
Nubia Sandstone

40. 40
Mechanical analysis of Nubia sandstone
Nubia Sandstone
The section can be divided into five major
lithologic units, in ascending order:
1. A basal unit of trough-cross-bedded sandstone
and conglomerate with non-bedded kaolinitic
sandstone;
2. gray and red shale and thin, sparsely
fossiliferous sandstone (Aswan area only);
3. tabular cross bedded sandstone;

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Mechanical analysis of Nubia sandstone
Nubia Sandstone

42. 42
Mechanical analysis of Nubia sandstone
Nubia Sandstone
The section can be divided into five major
lithologic units, in ascending order:
1. A basal unit of trough-cross-bedded sandstone
and conglomerate with non-bedded kaolinitic
sandstone;
2. gray and red shale and thin, sparsely
fossiliferous sandstone (Aswan area only);
3. tabular cross bedded sandstone;
4. current ripple-laminated siltstone and lenticular
sandstone; and

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Mechanical analysis of Nubia sandstone
Nubia Sandstone

44. 44
Mechanical analysis of Nubia sandstone
Nubia Sandstone
The section can be divided into five major
lithologic units, in ascending order:
1. A basal unit of trough-cross-bedded sandstone
and conglomerate with non-bedded kaolinitic
sandstone;
2. gray and red shale and thin, sparsely
fossiliferous sandstone (Aswan area only);
3. tabular cross bedded sandstone;
4. current ripple-laminated siltstone and lenticular
sandstone; and
5. an upper unit of green, blue, and red clay-shale

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Mechanical analysis of Nubia sandstone
Nubia Sandstone

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Mechanical analysis of Nubia sandstone
Nubia Sandstone

47. 47
Introduction
Nubia Sandstone

 Mineral analysis of Nubia sandstone
 References

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Mineral analysis of Nubia sandstone
Nubia Sandstone
Quartz over growth, partially altered feldspars and
interstitial clay. Over size pores resulted from
altered, partly altered feldspars and dissolved
grains. Secondary porosity is due to digenesis
processes. Over growth reduces porosity concave-
convex contacts elongated & triple point types of
contacts. Sometimes carbonate cements reduce
porosity. Good porosity-partially altered feldspars-
iron oxides and dissolution of feldspar cause
oversize pores. Sometimes porosity-quality
reduced due to the occurrence of iron oxides.

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Mineral analysis of Nubia sandstone
Nubia Sandstone

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Mineral analysis of Nubia sandstone
Nubia Sandstone
authigenic illite as grain coating showing irregular
flakes oriented perpendicular to grain surface and
some authigenic clay coating grains and fills the
interstitial pores are also occurred. Over growth
and the interstitial authigenic illite and mixed layer
occurred

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Mineral analysis of Nubia sandstone
Nubia Sandstone

52. 52
Introduction
Nubia Sandstone

 References

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References
Nubia Sandstone
AAPG Bulletin Volume 63 issue 1979 W. C. Ward,
K. C. McDonald (2), -- Nubia Formation of Central
Eastern Desert, Egypt--Major Subdivisions and
Depos.
Middle East Journal of Applied Sciences, 4(4):
1016-1022, 2014, Mineralogical and Mechanical
Compaction Characteristics of Nubian Sandstones,
Gebel Duwi, Central Eastern Desert, Egypt. R. A.
El-Mohammady, A. I. M. Ismail and M. Gameel.
The American Association of Petroleum Geologists
Bulletin V. 54, No. 3 (March, 1970), Nubian Group:

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