الفهرس 
Chapter I: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The study area lies to the east of Maadi and encompasses the Wadi Degla which is one
of the most important wadis in the north Eastern Desert. The Wadi and surrounding
high lands were declared protected areas in 1999 according to Law 102, 1983 in the
framework of protected areas in Egypt to protect the main natural resources represented
by geological formation, landscape and fauna and flora as the main attractive points to
visitors. The study area is bounded by latitudes 29° 57’ 57” & 29° 54’ 16” N and
longitudes 31° 19’ 18” & 31° 30’ 00” E.
The present study deals with the geology, geomorphology, delineation, characterization
of setting of caves and distribution in stratigraphic sequence of Eocene rock units in
Wadi Degla protected area in the East of Maadi–Cairo, Egypt. It aims also to study the
morphometric characteristics of the drainage basin of Wadi Degla to identify the main
threats and challenges with mitigating towards the natural and anthropogenic hazards.
Stratigraphically, the exposed rocks in the study area are of sedimentary nature.
Most of the study area is covered by carbonate sequences of Middle Eocene and
include two rock units Observatory and Qurn formations. The Obserbatory Formation
is subdivided into two members, Upper Building Stone Membe at the base and Guish
Member at the top. The second member exhibit an amazing and spectacular karst
features including cavities and caves. To represent stratigraphic setup of the study area
,three surface sections were measured and sampled.
Pertographically, the microfacies analysis of the limestones of the Upper Building Stone
and Giushi Members are examined and assigned to the following microfacies types:
Wackstone include : Foraminiferal bioclastic wackstone.
Packstones include :Molluscan foraminiferal packstone, Algal foraminiferal packstone,
Nummulitic packstone Sandy foraminiferal bioclastic packstone
Grainstones include : larger foraminiferal grainstone
Mudstone include :lime mudstone
Paleoenvironmentally, these facies are suggested to be deposited in warm, well
oxygenated, hyper- to hyposaline,shallow shelf environment with water depth less than
50 m for the Upper Building Stone Member,while the Giushi Member may be
deposited in normal marine, inner to middle shelf environment at depth not exceed
100m and moderate- oxygen conditions. the Qurn Formation may be deposited in
shelf lagoon to restricted platform. Faults are widely distrbuted through this area, most
of these faults are normal with small displacment and have three set of direction: E-W,
W-NW and NW sets.
Morphometrically, the analysis of drainage basin of Wadi Degla by using GIS
indicate that the basin has a dendritic pattern with fifth order stream and includes 1075
total stream in the catchment, out of which 542stream was identified in 1st order, 235
stream was in 2nd order, 126stream in 3rd order , 60 stream in 4th order and112 fifth
order streams. The total stream length for Wadi Degla watershed was 400.7 Km which
includes 258.8 Km in 1st order, 40.1 Km in 2nd order, 48.5 Km in 3rd order, 22. 1 in 4th
order and 31.2 km in 5 th . The low average mean bifurcation ratio of the basin under
study of 1.7 is an indication that parts of its segments (the fifth order) are liable to
flooding. The overland flow length in the Wadi Degla drainage basin is 0.2 km / km2,
indicating modest surface runoff, its mean that Wadi Degla high relief with short flow
paths and more venerable risk flooding expected.The geometry of the basin
calculation showed that Wadi Degla Basin length is 37 km with an area 177.6
km2 and basin perimeter is 93.3 kilometers.The Wadi Degla basin has an
elongation ratio (0.41), circularity ratio (0.26) and form factor (0.13) which
indicates that the shape of the basin tends towards elongation. The elongation
shape indicates that the basin will have a flatter peak of flow for longer duration.
Drainage density and drainage texture value of the Wadi Degla watershed was
2.26 km/km2 and 11.5 confirms that the catchment region has a very fine texture,
low permeability (carbonate rocks). The frequency of stream segments in the
study area, which is 6.05 per square kilometer. Due to the existence of ridges on
both sides of the valley, as well as a higher slope from the surface, this value refers to low impermeability of carbonate rocks and increased surface runoff.
The value of the total basin relief of the watershed in Wadi Degla is 528 m,
where highest and lowest elevations are 597 and 69 m, respectively. The relief
ratio of Wadi Degla basin is 5.6 m/km this high value indicates that the basin has
strong relief and steep slope.
Karstologically, the field study has been identified 21 caves in Wadi Degla
protected area mapped and inventoried from different points of view including,
location, the content of biological diversity, risk and hazards, and significance. The
inventory revealed that the caves in Wadi Degla range in length between 2m and 77 m
with width range from 0.5 to more than 6 m wide and height between 0.5 m to 7 m.
Most of the caves studied are phreatic in origin and developed on the bedding plain or
fractures or both of them and some formed along faults.
This study revealed that the Wadi Degla caves contain a variety of sediments of
both allochthones and autochthonous origin. One of the most important features that
distinguish some of these caves is the presence of allochthones deposits of sand, gravel
and mud preserved in these caves. This study suggests that the clastic sediments are
possibly derived from the Oligocene rocks in the east of study area, as indicated by the
presence of remains of silicified wood fossils and gravels. Autochthonous deposits are
represented in three of out 21 caves by flowstone, popcorn, gypsum flower shapes, and
fragments of limestone eroded from the walls or ceiling in addition to bats guano
deposits recorded in some caves.
Most of inventoried caves have been showed human disturbance represented by
trash, writing by graffiti on the walls and illegal digging to search for archaeological
remains.
Major organisms identified in the caves included bats of the species, Rhinopoma
hardwickii (large mouse-tailed bat), reptile species of Ptyodactylus guttatus Heyden,
(Fan-footed Gecko), pigeons of the specie Columba livia and Desert Eagle Owl.Generally, it can be stated that the Wadi Degla protected area caves have high
scientific, educational, and research values. Protection and conservations of the
recorded caves are available to a certain extent, but still not high enough to regulate the
visiting activities. The visitors’ awareness is at a very low level due to the lack of
adequate infrastructure and qualified guiding staff.
This study recommends, from an environmental hazards point of view, the Wadi
Degla Protected Area should be closed during heavy rainfall for visitor safety and also
avoid the establishment of any basic infrastructure in the vicinity of the Wadi pass.
Most of the caves should be closed for the protection of bats from anthropogenic
activities and the safety of users. The Wadi Degla protected area administrative should
prepare signposts warning the visitors from entering the cave without permission. In
addition to future work still needed further detailed sedimentological study and age
dating method to evaluate the real age of the sediments in the caves.