Baharia Oasis: Its Topography and Geology

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Page 63 - In one hill an ordinary yellow sandstone was observed, when followed up, to contain an increasing number of ferruginous concretions, at first in isolated lumps, or strings, but higher in such quantity as to present the appearance of a breccia, which latter gradually passed up into a hard dense mass of ferruginous quartzite.
Page 55 - Cenomanian aspect, although some of the forms (marked**) are indicative of a somewhat later age, ie, Turonian and Senonian. As the next bed above is the Danian White Chalk, it is probable that some of the upper beds of this series form a transitional stage between the Cenomanian and Danian. The presence of the bone-bed, as already mentioned probably of the same age as the Dakhla and Eastern Desert bone-beds, ie, Campanian, supports this view.
Page 62 - Ghorabi, in the extreme northern end of the depression. The hill consists of a mass of ferruginous material, including limonite, pisolitic iron ore, red and yellow ochre, etc., lying on a series of sandy shales, clays, and sandstones of Cretaceous (Cenomanian) age. Thin bands of limonite occur in the clays and sandstones, but the great mass of the mineral appears to form a distinct deposit capping the Cretaceous beds.
Page 49 - ... total thickness cannot be estimated. In the north part of the oasis they are capped, with apparent conformability, by Eocene limestones, although an intervening band of limestone-grit may occasionally occur. In the south, the series is followed by the higher Cretaceous divisions, while in the isolated hills within the depression these beds are capped either by Eocene limestones, by basalt or dolerite, or by Post-Eocene ferruginous sandstones and quartzitcs.
Page 29 - Eocene, is important as showing that whatever the age of the limestones at the actual edge of the south part of the oasis may be, the beds forming the plateau only a few kilometres east of the oasis are, like those which form the top of the northern scarp, of undoubted Eocene age. The nummulites were visible in the •Jordan's position for this point is approximately lat. 27° 46' 20
Page 60 - Eocene must be close to the edge of the plateau, while the folding doubtless accounts for the crystalline nature of the rocks and their poverty in fossils. South of the large hill, a second plateau is met with at a distance of about a kilometre eastward from the main scarp; this second plateau consists of soft chalky beds similar to those above-mentioned, underlain by clays and sandstones, while the main scarp still exhibits...
Page 60 - As the south point of the oasis is approached the limestones thin out, till at the end only a few beds of hard yellow-brown limestone occur in the clays ; these beds are continuous with those containing Cenomanian fossils on the west plateau. Thus at the south-east portion of the scarp the Danian is either absent, or represented by very thin beds at a little distance from the oasis. It might be suggested that the soft chalky...
Page 9 - On the stratigraphy and physiography of the Libyan Desert of Egypt : QJGS, v.
Page 21 - Eocene) and the hills seen from this road are doubtless composed of the same beds. The ridges crossed at 20 kilometres are formed of hard, compact, close-grained crystalline limestone, covered with more or less gypsum and flint gravel ; the limestone beds forming these ridges show dips which suggest the existence of a fault running NE-SW, parallel to the...
Page 49 - They consist of friable false-bedded variegated sands and sandstones, •with harder dark-brown ferruginous bands, alternating with sandy shales and clays, passing through every gradation. Some of the sandstones are micaceous. ' The clays are frequently saliferous, and bands of fibrous gypsum are occasionally seen.

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