joining them together to a new green valley in the desert 
  
similar to the Nile valley. Therefore, information on the 
availability and reserves of groundwater in that area is of 
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the utmost importance, and, in order to evaluate the ground- 
water situation, a thorough knowledge of the regional geology 
is needed. 
Secondly, starting with the discovery of several oil and gas T 
fields in Northern Egypt, the prospect of becoming a major oil ' 
producing country has spurned Egypt to begin an extensive 
overall exploration for oil and gas. Here again, the Western 
Desert may have to play an important role. 
Since the Sirte Basin in neighboring Libya is known as the 
major oil province of Africa, there are chances that similar 
geological and structural settings in Southwestern Egypt might 
also prove to be oil producing. For the evaluation of seismic 
and aeromagnetic surveys in respect to oil, the geological 
picture must become clear. In addition, the Western Desert 
could still be hiding valuable mineral resources beside the 
phosphate beds that are already being exploited near Kharga. 
In view of this background, the Deutsche Forschungsgemeinschaft 
has started a cooperation program with the Egyptian Academy 
of Scientific Research in order to speed up the geological 
exploration of Southwestern Egypt. The help of both organiza- 
tions is gratefully acknowledged here. The authors are also 
indebted to Conoco, Marathon and Pecten oil companies which 
permitted the use of their field camps and contributed to the 
printing costs of the interpretation maps. 
2. Geological Background 
  
The geological knowledge of the area to be investigated and 
mapped was of a rather unbalanced nature when the work 
described here started in December 1976. The northern part of 
the Western Desert consists of a marine series from Late