[47]Beadnell, Dakhla Oasis, its Topography and Geology. Geol. Surv. Egypt. Report, 1899, Pt. IV. Cairo. 1901, pp. 96-98.
[48]Barron and Hume, Topography and Geology of the Eastern Desert of Egypt, Geol. Surv. Report, Cairo, 1903.
[49]It may perhaps be that the lowest limestone bed disappears, having thinned out, in which case it is difficult to distinguish the sandstones and clays of this division from those of the one below.
[50]Zittel, op. cit.
[51]As it seems probable that the Lower Mokattam is a somewhat local development of the upper part of the Libyan Series, and it being difficult or impossible in many areas to separate the two, we shall in our description of the Eocene of this oasis make no attempt at a division.
[52]Chapman, Geol. Mag. Dec. IV, Vol. IX, Feb. and March, 1902, pp. 62-67, 106-114.
[53]It should be noted here that the presence of an overlap was suspected by Capt. H. G. Lyons as long ago as 1894, as in his paper (op. cit. 535) he says:—
“At the north-east and east of the Baharia Oasis the Upper Mokattam beds, characterized by Ostrea Fraasi and O. Cloti (as kindly determined by Dr. Zittel), occur 30 miles north-east and 20 miles east of Upper Cretaceous beds containing Exogyra Overwegi in the oasis, and with a difference in altitude of less than 200 feet. As there is no marked dip of the beds, we have evidently an overlap of the remainder of the Cretaceous beds and the Libyan and Lower Mokattam beds of the Eocene, and this inference is borne out by the short distance between the Cretaceous and Miocene outcrops to the west on Dr. Zittel’s route to Siwa.”
[54]Voyage à Méroé, I., p. 189. The same observer also noted the presence of nummulites in the northern scarp, and the ferruginous nature of the sandstones composing the hills of the oasis (p. 190).
[55]Zeitsch. d. Ges. f. Erdkunde zu Berlin, 1885, p. 134.