THE 



GEOLOGICAL MAGAZINE. 



NEW SERIES. DECADE V. VOL. VIII. 



No. I.— JANUARY, 1911. 



OIRIG-IIN" ^I_, AETICLES. 



I. — The Gulf of Suez. 1 

 By John Ball, Ph.D., D.Sc, F.G.S. of the Geological Survey of Egypt. 



IN a previous paper published in this Magazine, 2 I gave reasons 

 for the belief that neither the Gulf of Suez nor the valley of 

 the Nile* owes its origiu to trough-faulting, as was at that time 

 generally supposed. The skeleton of the argument was as follows : — 



1. Extensive faulting at the faces of the scarps of the Nile Yalley 

 and Gulf of Suez cannot be held to be evidence of trough-faulting, 

 since the same can be observed along the scarps of the Wadi Araba, 

 the structure of whose floor shows it to be an eroded anticline, and 

 the faults along its scarp-faces to be merely huge landslips. 



2. The faulting observable immediately along the coast of the Gulf 

 of Suez is of an exactly similar nature to that above mentioned, and 

 along part at least of the gulf the strata dip away from the sea on the 

 opposite coasts, leading to the inference that the Gulf of Suez is, like 

 the Wadi Araba, an eroded anticline. 



3. If it be granted that the Gulf of Suez is not a trough-fault, the 

 argument against the Nile Yalley being a trough-fault is strengthened, 

 the support of parallelism being removed. 



A discussion of the paper with various fellow-workers has indicated 

 entire agreement as to the Nile Yalley having been cut out by erosion, 

 but at the same time has shown a tendency to suspension of judgment 

 regarding the origin of the Gulf of Suez. I have therefore searched 

 diligently for further facts which might throw light on the origin 

 of the gulf. Since writing my last paper 1 have spent a season 

 surveying in the neighbourhood of Gebel Zeit. Though the work was 

 confined, by other considerations than geology, to a small part of the 

 Egyptian side of the gulf, and has in consequence not furnished much 

 additional evidence, I may say that such observations as I was able 

 to make were all to my mind corroborative of the conclusion to which 

 I had already been driven, viz. that the Gulf of Suez owed its origin 

 to erosion and not to trough-faulting ; for example, I remarked that 

 the Nubian Sandstones on the north-east flank of Gebel Zeit dip 

 strongly away from the gulf, which one would not expect them to do 

 if the gulf had been faulted down. Since more extended field 



1 Communicated by permission of the Director-General, Survey Department, Egypt. 



2 Geol. Mag., Dec. V, Vol. VII, pp. 71-6, 1910. 



DECADE V. VOL. VIII. NO. I. 1 



