Geology of Dakhla Oasis, Western Desert, Egypt
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the depressions, although tectonic activity also may have contributed to their formation. All of the oasis depressions occur in areas where hard rocks overlay soft ones;
once the hard overlying rock was eroded, the softer rock was hollowed out quickly
and stripped away.
Geomorphologically, the study area is divided into the following three main
distinct geomorphic units:
1. The Dakhla—Abu Minqar Plateau (The limestone plateau)
2. The Scarp Face
3. The Dakhla Depression
2.1 The Dakhla—Abu Minqar Plateau
The Dakhla—Abu Minqar plateau makes a part of the main plateau between Kharga
and Dakhla depressions. The plateau surface overlooks the Nubian depression of
the Western Desert to the south, whereas it stretches northward forming the general
surface of the central part of the Western Desert and the floor of the Farafra Depression. The surface elevation ranges from 400 m. to 500 m. above sea level. The
surface of the plateau is made of hard, greyish white to yellowish-white limestone’s
of Tarawan and Kurkur Formations. The effect of wind erosion is highly manifested
in the formation of Yardings and wind flutes especially developed in the limestone
ridges which namely Kharafish (Fig. 2).
Generally, the main rock surface of the plateau is broken into rugged and rough
landscape which is sometimes veneered by limestone rubble.
Yarding
Fig. 2 Google Earth image showing limestone Yarding (Kharafish) at the top of the Plateau
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the depressions, although tectonic activity also may have contributed to their formation. All of the oasis depressions occur in areas where hard rocks overlay soft ones;
once the hard overlying rock was eroded, the softer rock was hollowed out quickly
and stripped away.
Geomorphologically, the study area is divided into the following three main
distinct geomorphic units:
1. The Dakhla—Abu Minqar Plateau (The limestone plateau)
2. The Scarp Face
3. The Dakhla Depression
2.1 The Dakhla—Abu Minqar Plateau
The Dakhla—Abu Minqar plateau makes a part of the main plateau between Kharga
and Dakhla depressions. The plateau surface overlooks the Nubian depression of
the Western Desert to the south, whereas it stretches northward forming the general
surface of the central part of the Western Desert and the floor of the Farafra Depression. The surface elevation ranges from 400 m. to 500 m. above sea level. The
surface of the plateau is made of hard, greyish white to yellowish-white limestone’s
of Tarawan and Kurkur Formations. The effect of wind erosion is highly manifested
in the formation of Yardings and wind flutes especially developed in the limestone
ridges which namely Kharafish (Fig. 2).
Generally, the main rock surface of the plateau is broken into rugged and rough
landscape which is sometimes veneered by limestone rubble.
Yarding
Fig. 2 Google Earth image showing limestone Yarding (Kharafish) at the top of the Plateau