الفهرس 
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Abstract
The present thesis Introduce a companson between the
groundwater in the Miocene aquifers in some localities east of the Nile
Delta from the hydrochemical and isotopical points of view. These
localities are: Cairo-Suez desert road, Heliopolis basin and Inshas area.
The study involved geomorphological and geological survey
depending mainly on the previous works while the hydrogeological,
hydrochemical and environmental isotopes were studied depending on the
field and laboratorial measurements.
This thesis includes the following chapters:
Chapter I: Methodology
This part includes the procedures used to determine hydrogen ion
concentration (pH), electrical conductivity (EC), total dissolved solids
(TDS), major constituents (Ca++,Mg++’Na+,K+,C03--,HC03-, S04-, cr
and SiOl), minor constituents (N03-, P04--, B+++and Fe) as well as
stable and radioactive isotopes (oxygen-I 8, deuterium, tritium and
carbon-14). It also includes the chemicals and apparatus used in the
analysis.
Chapter II: Geomorphological, geological and hydrogeological
aspects
I-Geomorphology:
The area under investigation slopes generally northward and is
classified into three geomorphologic units which could be described as
follow
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(i) Moqattam-Ataqa structural plateau.
This unit extends from Gebel EI Mokattam westward to Gebel
Ataqa eastward. It extends in an E-W direction for a distance of about
135km and forms a series of highly elevated disconnected hills.
(ii) Structural ridges and depressions.
To the north of Moqattam-Ataqa plateau, a senes of structural
ridges and depressions are developed. They are represented by four
subparallel structural ridges:
- Anqabiya-Nasuri.
- Dibba-Iweibied.
- Geniefa-Shubrawiet,
- Shubrawiet-Hamza.
These structural ridges are separated by two main shallow
depressions:
-Heliopolis depression and
-EI Dakruri depression.
The ground elevation of these depressions ranges between 15m and
240 m above sea level. They act as water-collecting basins during winter
times.
(iii) Belbeis-EI Tell EI Kebeir-EI Salhiya old deltaic plain.
This plain: slopes northward (4m/km) and characterized by a
moderately low relief. Inshas area lies within Umm Gidam gravelly
plains, which are located within this old deltaic plain.
2- Geology
The area of study has a sedimentary cover ranging in age from
Eocene up to Pliestocene-Holocene (Quaternary). Great attention is paid
to the Miocene rocks.
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(i) Quaternary deposits
The Quaternary deposits are mainly composed of sand sheets and
recent deltaic silt with average thickness about 5 m, and the Pleistocene
deposits which are dominated by sand and gravel with clay lenses with a
thickness ranges from 50 m to about 200 m which is increasing toward El
lsmailia canal
(ii) Miocene deposits
Miocene sediments cover a large area along Cairo-Suez desert road
and at Heliopolis basin with a thickness reach about 250m, they overlie
unconcformably the Oligocene. Lithologically, they are represented by
sandstone and sandy limestone and are unconformably underlie the
Pliocene, or sometimes, the Pleistocene sediments. They are divided into
two units, the lower unit is made up of marine sediments and the upper is
made up of non-marine fluviatile sediments. The Miocene sediments in
Inshas area are rmconformably underlying the Pleistocene sediments.
These sediments are of marine origin and consist of dark grey clay and
calcareous marl interbedded with gravel and sand bands.
3-Hydrogeology
Hydrogeologically, the investigated area includes two aquifers, the
Quaternary aquifer and the Miocene aquifer.
(i) Quaternary aquifer:
This aquifer covers a great parts to the east of the Nile delta. Its
thickness shows gradual increase towards the Nile Delta. The Quaternary
aquifer is mostly under semi confined conditions due to the presence of
overlying clay. It is subjected to unconfined conditions in Inshas area due
to the absence of the clay confining beds. It is mainly recharged from the
main Nile Delta aquifer and seepage from surface water systems.
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--- - . -- ----. - ----- ---- ------
(ii) Miocene aquifer
The Miocene aquifer along Cairo-Suez desert road and at
Heliopolis basin is mainly composed of sand and gravel with clay and
limestones interbeds with an average thickness of about 250 m. The
Miocene aquifer within this area is subjected to unconfined or
semiconfined conditions with a depth to water ranges from 160 to 240 m.
The Miocene aquifer in Inshas area is mainly composed of grey
clay and calcareous marl interbedded with gravel and sand bands. Its
thickness reaches 65 m. The depth to water varies from 14m to 36 m.
*Hydrogeological cross sections:
The three hydrogeological cross sections constructed in the study
area show that generally, the direction of groundwater flow is generally
from SW to NE.
Chapter III: Hydrochemical aspects.
The main aim of this chapter is to know the water chemistry, water
types and to asses the hydrogeochemical processes affecting water
quality. Seventy eight water samples were collected from the study area.
Fifty three of them represent the Miocene aquifer, sixteen represent
Pleistocene aquifer, five represent mixed water and four represent surface
water.
*Hydrochemistry of surface and Pleistocene groundwater:
The total dissolved solids (TDS) in the surface water samples (El-
Ismailia canal) ranges between 196 mg/l and 203 mg/l, reflecting fresh
water type. On the other hand the total dissolved solids of the Pleistocene
groundwater ranges between 499 mg/l and 3511 mg/l, reflecting fresh to
brackish water type.
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*Hydrochemistry of Miocene groundwater:
The study of the chemistry of the Miocene groundwater is the main
target of this thesis. The following topics are discussed:
(a) Total salinity:
Along Cairo-Suez desert road, the salinity ranges from 6194 mg/l
to 7897 mg/I and from 3651 mg/I to 6802 mg/I at Heliopolis basin. In
lnshas area, it ranges from 3433 mg/I to 10680 mg/1. Generally, the
salinity in the aboye areas indicates brackish to saline water type.
(b) Alkalinity:
Along Cairo-Suez desert road , the alkalinity ranges between 96
mg/I and 177 mg/I as CaC03 where it ranges between 27 mg/l and 215
mg/I at Heliopolis basin. It has a relatively high value in lnshas area due
to the influence of meteoric water rich in carbonate and bicarbonate. It
ranges between 80 mg/l and 304 mg/1.
(c) Hardness:
Generally, all the Miocene groundwater samples are classified as a
very hard water.
It ranges between 2659 mg/I as CaC03 and 4655 mg/l along Cairo-
Suez desert road and ranges from 989 mg/I to 3664 mg/I at Heliopolis
basin. It ranges between 639 mg/l and 3880 mg/l at Inshas area.
(d) Major ion relations:
The study revealed that, the Miocene groundwater samples have
CI-Na type and the combination between major anions and cations
reveals three main groups of hypothetical salts. these are:
Group J : composed ofNaCI, MgCh, CaCh, CaS04, and Ca(HC03)2.
Group II : composed ofNaCI, MgCh, MgS04, CaS04 and Ca(HC03)2.
Group Ill: composed ofNaCI, Na2S04, MgS04, CaS04 and Ca(HC03h.
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Two types of water arc existed, namely Mg-CI and Ca-CI. The
water of Ca-CI reflects the old marine water with salt combination
represented by group 1.
This type is represented in most water samples along Cairo-Suez
road and Heliopolis basin. In case of Mg-CI type showing recent marine
origin with salt assemblage represented by group II is exhibited in some
samples in Heliopolis basin. The existence of Mg-Cl type refers to old
marine water that was subjected to more developed stages of flushing by
deep meteoric water percolation. Most of the samples in Inshas area
reflects mixing water ofNaS04 type. Such water is characterized by salt
combination represented by group II.
mGeochemical classification of groundwater:
By using the semi-logaritmic and the trilinear diagrams water
analysis diagram, the Miocene groundwater of the study area shows the
following:
Along Cairo-Suez road, the groundwater has the sequence: Ca(Mg)
< Na < CI > S04> HC03 and occupies area (6) in the diamond shape
reflecting the secondary salinity character. This could be attributed to the
overpumping from these water wells.
At Heliopolis basin, the groundwater has the sequence: Ca > Mg <
Na < CI > S04> HC03 and occupies area (6) and (7» in the diamond
shape, reflecting the secondary and primary salinity character. This
reveals marine origin and ion exchange processes. In Inshas area, the
sequence of groundwater samples is: Ca> Mg < Na > CI(S04) > S04(CI)
> HC03 and occupies area (7) in the diamond shape reflecting the
primary salinity character. This reveals the effect of marine growidwater
with meteoric water.
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The Miocene groundwater samples in Inshas area (Nos. 49, 50 and
51) and some samples in Heliopolis basin (Nos. 41, 43 and 44) are less
depleted than the rest of the Miocene samples. These can mark a zone of
mixing and interconnection with the Quaternery aquifer and the recent
recharge. The Pleistocene water samples are not as enrich as the Nile
water system.
This confirms the presence of zone of mixing and hydraulic
connection between the present time recharge source and pluvial time
water entrapped between the rock pores since Pleistocene-early
Holocene. This zone is present in the northern boundary of the study area
(EI Adlia water wells).
The areal distribution of 0-18, 0 and T are highly compatible
together where 0-18, 0 and T get the lowest concentration values in the
central part of the study area at Heliopolis basin.
There seem present a structural break between Heliopolis basin and
the other localities in the area of study, where the structural features resist
the recent recharge to the basin while it reaches the northern and eastern
portion of the area.