الفهرس 
GROUNDWATER GEOLOGY AND AQUIFER DISTRIBUTIONOnly 14 pages are availabe for public view
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Abstract
The study area lies between Longitudes 30° 00’ & 30° 50’ E and
Latitudes 30° 00’ & 30° 33’ N. It extends from km 62 (Cairo-Alex. Desert
Highway) in the south to El-Alamin Desert Road at krn 126 to the north.
The study area covers an area of about 800000 Feddan and the present
study depends on the data obtained from about 557 wells out of existing
2000 working wells.
The present study has indicated the presence of three different
aquifers having different geological ages but they are hydraulically
connected. Those three aquifers are the Pleistocene, the Pliocene and the
Miocene clastic rock units. The distribution and characteristics of such
units ar~ widely discussed in this thesis.
from the analysis of a number of pumping tests, the
transmissivity of the Pleistocene, Pliocene and Miocene aquifers are 60
m2/day, 1275 m2/day and 260-4600 m2/day, respectively.
One of the most important results reached in the present work is
the assessment of the groundwater level variations during a period of
more than 10 years. This assessment has, obviously, revealed that a
serious depletion of the rate of I rn/year happens as a result of the
intensive pumping in the great farms.
The rate of the water level depletion (1m/year) is a serious
indicator for the mismanagement of the water resources in the Miocene
aquifer in Wadi El-Farigh. Actually, the continuous decrease in the
saturated thickness of that aquifer will lead to a tragedic problem in the
agricultural development in this area. Bearing in mind that the saturated
thickness of the Miocene aquifer in Wadi El-Farigh does not exceed 150
m as a maximum value and 100 m as an average value, one should give a
warning for the applied water exploitation rates. The most affected areas
with a total drawdown (8-12m) during 10 years are the areas lying close
to the Cairo-Alexandria Desert Highway; i.e. the areas of high
accessibility. The chemical analysis shows that water salinity CTDS) ranges
between 351 ppm and 1630 ppm for the Pleistocene aquifer, between 766
ppm and 5847 ppm for the Pliocene aquifer and between 264 ppm and
991 ppm for the Miocene aquifer.
The change detection of the surface hydrological features
(cultivated area, natural and artificial lakes and sabkhas) is performed by
using remote sensing and GIS techniques through comparing two
different dates of imagery to detect land cover change over time between
1993 and 2002.
In 1993, the areas of the cultivated land irrigated by groundwater,
the sabkha, natural lakes at Wadi El-Natrun, and the barren desert are
about 27992 Feddan (irrigated by 0.56x106 m3/day of groundwater),
2719 Feddan, 2252 Feddan and 780439 Feddan, respectively.
In 2002, the areas of the cultivated land by groundwater, the
sabkha, natural lakes at Wadi El-Natrun, artificial lakes and the barren
desert are 78404 Feddan (irrigated by 1.57x106 mJ/day of groundwater),
1740 Feddan, 1925 Feddan, 71 Feddan and 731262 Feddan,
respectively.
Different GIS layers are constructed including the geographical
distribution of groundwater salinity, water depth, specific capacity, depth
of well drilling and expected dynamic water level.
Different weights were given for the above five layers to give two
scenarios according to the needs and requirements of the investors. In the
first scenario, the economic factor is the dominant factor, i.e. the low cost
of groundwater extraction is the main target of the investors. from the
final model map of this scenario, one can conclude that the best areas
with low cost but of low quality (Pliocene aquifer) are covering the area
from El-Sadat Road up to El-Alamein Road (Wadi El-Natrun area). In
the second scenario, the groundwater quality is of prime importance
(drinking and bottling). from this final model map, one can conclude that
the recommended areas to be invested are the southern and western areas
at Wadi El-Farigh (Miocene aquifer) and the areas east to Wadi El.
atrun (Pleistocene aquifer).