الفهرس 
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Abstract
The present work dealt with detailed sedimentological, mineralogical,
textural and chemical compositions and aspects of some surface sediments.
These sediments are represented with sands, clays and carbonates which are
studied from eleven localities scattering at east and west of Cairo-Alexandria
desert road.
Furthermore, these investigations were carried out on representative
selected surface sediments to determine their environment of deposition,
transporting agent and source rock.
In addition to the previous investigations, the present study dealt
with studying the possible utilization of some raw materials (carbonate and
clay deposits) in building purposes through studying their technological
characteristics. Moreover, some natural additives (sand and grog) were used
with the studied Egyptian clay (Hagif Formation, locality V) to improve their
technological properties.
Lithostratigraphical units
In the present study, five rock units are described lithologically in the field
(other rock units in the area under investigation out of the present study)
through studying several stratigraphic sections. The studied rock units arranged
from the oldest to the youngest as follows: HagifFormation, Muluk Formation,
Qataji Formation, Diba Formation and Stabilized Sand dunes.
Hagif Formation (Middle Miocene) in the present study is divided into
two members; Carbonate-Clastic at top and Clastic at base. Lithologically, the
Hagif Formation is represented in locality V by the Carbonate-Clastic Member,
which consists mainly of fossiliferous carbonate deposits intercalated with the
argillaceous beds, while at locality VII the studied section is composed of
the two members; Clastic-Member at base and intercalation of carbonates and
argillaceous deposits at top (Carbonate-Clastic Member). Hagif Formation at
the studied localities is unconformably overlain by the Qataji Formation.
Carbonate-Clastic Member of the Hagif Formation at the studied locality
may be deposited in marine environment, while the Clastic Member may be
deposited in fluvial environment.
Muluk Formation (Late Pliocene) at the studied locality is represented by
Clayey Member of Abou Khadrah (1973), which consists of clay; greyish
green, compact, gypSl~OUSs,aliferous and unfossiliferous. The Clayey Member
may be deposited in marine environment under reducing condition. However,
probably this member was deposited in marine environment.
Qataji Formation (Plio-Pleistocene) at the studied localities is composed
of buff to dark brown, very hard and oolitic sandy limestone. This formation
may be deposited in fluvial environment under semi-arid climate.
Diba Formation (pleistocene) in the present study is classified into two
members; the upper Gravely Member and the lower Sandy Member.
Gravely Member is composed of loose to semiconsolidated gravels of
metamorphic and igneous rock fragments, in addition to the quartz and chert
pebbles. The occurrence of rock fragments (basement and sedimentary) may be
pointed to recycling from the basement source (igneons and metamorphic) or
reworking from previously deposited sedimentary rocks.
Gravely Member of the Diba Fonnation may be deposited from braided
streams occurred at low sinuosity and steep slopes of the channel, low threshold
of bank erosion (weak banks) with series of cataractswhich responsible for the
long transport of the heterogeneous gravels which may be either from its
highland source area in the Eastern Desert along the Red Sea mountains
(Mohamed, 1994) or older sediments which transportedby Prenile River.
Sandy Member of the Diba Formation is composed mainly of yellowish
to greyish white, loose, fine to medium grained, cross bedded, ill-sorted
sands with carbonate streaks and some quartzpebbles. The sedimentological
investigations indicated that the sediments of Sandy Member in locality represent levee deposits due to occurrence of the vertical sequence of
alternating sandy and muddy layers in addition to presence of rootless.
Consequently, Diba Formation in all probability was deposited in fluviatile
environment.
Stabilized Sand dunes (Pleistocene) are composed of yellow, medium to
coarse grained, loose and ill-sorted sands. These sands were deposited in desert
environment by winds.
Sand
Representative sand samples from the Hagif Formation, the Diba
Formation and the Stabilized Sand dunes were studied mechanically and
mineralogically. The size parameters (Mz, 0’1’ SKI and KG’) of Folk and Ward
(1957) were calculated. Scatter plotting diagrams are drawn for each pair of
these size parameters. The four moments of Friedman (1961 & 1967) were
calculated and plotted as scatter diagrams. The relationship between the grain
size and hydraulic conditions during transportation also were discussed
according to Passega and Byramjee (1969). The four discriminant functions of
Sahu (1964) are calculated to clarify the environment of deposition.
_ Sands of the Stabilized Dunes are very coarse to medium sand sizes, poorly
to very poorly, range from fine skewed to coarse skewed and from very
platykurtic to leptokurtic classes.
_ Sands of the Gravely Member of the Diba Formation are pebbley to medium
sand sizes, vary from moderately well sorted to very poorly sorted, range
from strongly fine skewed to strongly coarse skewed and range from very
platykurtic to leptokurtic classes.
_ Sands of the Sandy Member of the Diba Formation are medium and fine
sand sizes, poorly sorted, range from fine skewed to strongly coarse
skewed, and fall within mesokurtic and leptokurtic classes.
Sands of the Carbonate Member of the HagifFormation distinguished by
their medium sand size, poorly sorted sand, coarse skewed sand and
mesokurtic and leptokurtic classes.
The calculated size parameters have been plotted for the studied sediments
against each other to recognize their depositional environments using the
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boundaries of Friedman (1961&1967) and Moiola (1968) and showed that
majority of the examined sands of the studied rock units are plotted the river
environment.
Plot of the C-M diagram showed that the majority of the studied sediments
probably transported by rolling motion with some minor graded suspension.
The discriminant functions of Sahu (1964) indicated that majority of the studied
sand samples were deposited in turbidity environment.
Results of light and heavy minerals show that the light fractions are
mainly composed of quartz grains and other minerals with percentage about
2% from calcite mica and clay minerals. The absence of feldspars can be
attributed to their removal during transportation process because it is physically
weaker than quartz grains. The heavy fractions showed relative enrichment of
epidotes and amphiboles than pyroxenes in the non-opaque sand fractions.
from the mineralogical studies and according to Hubert (1971) the
studied sands of the Diba Formation may be derived from high rank
metamorphic (may be derived from uncovered crystalline basement complex in
Sudanese-Egyptian borders or equatorial sub-Saharan Africa and transported
through the Neonile River) and ash fall rocks (may be derived from volcanic
rocks of the Ethiopian Plateaux and transported through the same river). The
Stabilized Sand dunes may be derived from the reworked sedimentary rocks.
The studied sediments of the Clastic Member of the HagifFormation may
be derived from high rank metamorphic and ash fall source rocks (may be from
the Eastern Desert mountains through the Eonile River tributaries which
drained on the Red Sea mountains during Miocene period, Said, 1993).
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Clay
Representative clay samples representing the Muluk and Hagif
Formations were studied texturally, mineralogically and chemically.
Texturally, the studied clay samples fall in well sorted silty clay, fairly
sorted clayey silt and in fairly sorted sandy silt categories.
Mineralogically, maiority of the studied clay samples of the Hagif
Formation is composed mainly of montmorillonite, kaolinite and illite
minerals (in decreasing order of abundance), while the studied clay sample of
the Muluk Formation is composed of montmorillonite and lesser amount of
kaolinite mineral.
Majority of the studied non-clay minerals in the samples were represented
by plagioclase and quartz minerals.
There are a good agreement in the results of mineralogical analyses with
these obtained from chemical analyses.
In the present study, it can be concluded that the clays of the Carbonate-
Clastic Member of the Hagif Formation and Muluk Formation may be
deposited in marine environment, while that of the Clastic Member of the
Hagif Formation may be deposited in fluviatile environment.
In the experimen1al work (part 2), the fired clay articles of the used
montmorillonitic clay without additives are cracked at all firing temperatures
(8000C, 850°C and 900°C) due to the high content of montmorillonite mineral
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and soluble salts. Hence, sand and grog additives were used as non-plastic
materials with different percentages (15,25,35 & 50 % by weight) with the
used clay as an attempt to improve their technological properties.
The optimum physic:o-mechanical properties were obtained with mixes
containing 15% grog fired at 9000 C and 15 % sand fired at 800
0
C.
Mixes of the used montmorillonitic clay with various percentages of grog
additive save the workable water, modify the physical mechanical properties
into reasonable ones and have much lower corrosive action on the metals of
equipments than caused by the clay/sand mixture.
Finally, addition of grog as well as sand with various percentages led to
improve some of technological characteristics (physico-mechanical properties) of
the used clay. Moreov”r, this montmorillonitic clay can be used successfully in
cement manufacture.
Carbonate
The studied carbonate samples representing the Carbonate-Clastic
Member of the Hagif and Qataji Formations were studied petrographically,
mineralogically and chemically.
petrographically, the studied carbonate samples are divided into two main
lithofacies as given below:
_ The limestone lithofacies: Classified into four common microfacies types,
these are: The lime-mud (recorded in Qataji Fm. and HagifFm.), the
wackestone (recorded only in Hagif Fm. and subdivided into the algal
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foraminiferal wackestone sub-microfacies), the packstone (recorded only
in Qataji Fm. and subdivided into sandy pisoidal packstone submicrofacies)
and the grainstone (recorded only in Qataji Fm. and
subdivided into sandy foraminiferal and algal grainstone sub-microfacies)
_ The dolostone lithofacies: Recorded only in the base of the Carbonate-Clastic
Member of the Hagif Formation and is composed mainly of fine-grained
rhombic dolomite mineral.
Algal foraminiferal wackestone microfacies of the Hagif Formation may
be deposited in the shallow marine environment (subtidal zone), while the finegrained
dolostone microfacies of the same formation may be deposited in the
intertidal zone.
Mineralogically, many of carbonate rock types could be recognized in the
Carbonate-Clastic Member of the Hagif Formation these are: Dolomitic
limestone, dolostone, limestone and sandy limestone, while in the Qataji
Formation only sandy limestone rock is present.
Chemically, all of the studied carbonate rocks are characterized with
presence of calcium oxide as the main oxide and high values of loss on
ignition.
In the experimental work (part 2), the studied carbonate rocks are
dolostone and sandy limestone. The dolostone is used as cubes (5 em. side
length), while sandy limestone rock is used as aggregates (sizes 1,2 & 3).
Some of chemical and physico-mechanical tests were carried out on these
cubes and aggregates following ESS and ASTM specifications.
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The results of chemical and physico-mechanical properties clarified the
following:
1- The studied sandy limestone aggregates fall in limits of Egyptian Standard
Specification 1109: 1971 and American Standard Specifications C3 3-90.
Consequently these aggregate can be used successfully in concrete in
addition to their uses in road works.
2- The studied dolostone cubes generally fall out of the standards specification
of building units. Moreover, they may be used as partition units of
buildings, but must be protected from water.
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