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Prof. J. W. Daicson — Notes on the Geology of Egypt. 



beds of carbonized wood, striated leaves and stems resembling those 

 of reeds. The Cretaceous formation does not, however, attain to 

 so great a development in Egypt as in Syria, and this, I think, 

 is an important point with reference to the attempts which have 

 been made to correlate the rocks of the two regions. We shall best 

 understand their true relations by studying a section geographically 

 intermediate, which we may find on the shores of the Red Sea, sixty 

 miles to the eastward of the great Mokattam section near Cairo. 



Tracing the Mokattam range to the eastward, in Jebel Attaka on 

 the Red Sea, it rises to a considerably greater elevation, and while 

 its upper part consists of Eocene Limestone with Nummulites ^ and 

 other characteristic fossils, its lower part is Cretaceous, and holds 

 Hippuntes and Ostrea larva. The Cretaceous here consists of hard 

 limestones, not, in so far as I know, found in the Nile valley, but 

 comparable with those seen farther east and north in Judea and the 

 Lebanon, while the Eocene beds appear to be less highly developed 

 and less purely calcareous than in the Nile. The structure of Jebel 

 Attaka, in short, appears to afford a clue to the apparent anomalies 

 of the distribution of the Cretaceous and Eocene in Egypt, Arabia, 

 and Syria. It would seem that while in all these countries the 

 Cretaceous and Eocene are conformable, and closely associated with 

 each other, they have from the first been unequally deposited. The 

 calcareous members of the Cretaceous, slenderly developed in Egypt, 

 increase in volume on the Red Sea, and attain their maximum in 

 Syria, while those of the Eocene show their greatest thickness in 

 Egypt and become depauperated farther to the east. This is at 

 least what appears to me the obvious explanation of the difficulties 

 which have occurred in correlating the Cretaceous and Eocene beds 

 of these countries. 



Fig. 4. — Section at Jebel Attaka, partly after Le Vaillant. (E) Eocene ; (Cr) 

 Cretaceous, including (a) White Chalky Limestone ; {b) Red and Greenish 

 Marl ; (c) Hard Limestone and Dolomite with Hippurites, Ostrece, etc. ; 

 ( V ) Position of Quarry ; (x x) Supposed Line of Fault. 



1 It has been stated that Nummulites do not occur here : 

 as to find specimens of coarse limestone lull of them. 



but I was so fortunate 



