| Textularia? gramen | N. discorbina |
| Globigerina bulloides | N. sub-discorbina |
| Operculina complanata, var. discoidea | Orbitoides (Discocycloides) dispansa |
| Nummulites gizehensis, var. Pachoi | (O. dilabida, Schwager). |
| N. curvispira |
Within the synclinal fold at one point ([Plate VII]), 17 kilometres north-east of Ain el Haiss, Eocene echinids and nummulites were found, but the beds from which they had weathered had been almost completely removed by denudation. The echinids have been recognized by Blanckenhorn as the following:—
| Porocidaris Schmedeli. |
| Echinocyamus luciana. |
| Sismondia Sæmanni. |
The following two species of nummulites have been determined by Chapman:—
| Nummulites Beaumonti. |
| N. sub-Beaumonti. |
Beds of east side of depression.In the scarp due north of Harra, the Cenomanian sandstones and clays with Exogyra mermeti and E. africana are conformably overlain by a hard yellow crystalline limestone containing small nummulites; so that here the Eocene clearly overlies the Cenomanian beds. If this upper limestone bed be followed southwards along the scarp (see the sections on [Plate VIII]) it appears to be continuous as far as the road leading to Ain Haswi, where the ground forming the bottom of the oasis-depression rises to the level of the limestone, and the clays are completely hidden by sand and limestone-debris. There commences here, however, a considerable thickening of the limestones, and hard brown limestones, with calcite-filled cavities, and some soft earthy beds come in; so that here we have the beginning of the series (No 6) which has been described as recurring on the opposite scarp in the same latitude, and which forms the hills north-west of Harra. The topmost bed of the scarp is a hard crystalline limestone, which appears continuous with that containing nummulites further north, and the top of the plateau is therefore probably here also Eocene. A little further south, the plateau-surface is covered with countless small hills of white chalky limestones with siliceous beds; these beds were searched without result for fossils, but as they overlie the hard crystalline rock, above mentioned as probably Eocene, they must be of Tertiary age, and therefore do not correspond with the Danian white chalk of the western plateau. As the large hill near the plateau east-north-east of Ain el Haiss is approached, the thickening of the lower crystalline brown and grayish-white limestones is very marked, and here they probably comprise both Cenomanian and Danian rocks; but the dip south-eastward is so strong that the 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 brown and grayish crystalline limestones, though both the dip and the thickness of these beds become gradually smaller. 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 limestones which form the second or upper plateau correspond with the Danian white chalk of the west side; but several considerations tend to negative this view. In the first place, it has been mentioned above that similar soft chalky limestones occur at about the same horizon further north, where they overlie beds which are probably Eocene. Again, on the line followed from the south end of the oasis of Minia, nummulites were found in abundance only a few kilometres away from the oasis. And lastly, these chalky limestones never show folding comparable with that of the lower beds, a fact which seems nearly conclusive in view of the unconformity known to exist at other points between the Cretaceous and the Eocene.
If the Eocene age assigned above to the chalky limestones of the eastern plateau be correct, it is possible that the clays and sandstones which underlie and separate them from the Cretaceous limestones may represent the Esna Shales of the more southern oases, though sandstones are elsewhere absent from this series.
Unconformity and overlap.—From the above description of the Eocene rocks of Baharia we see that their relation to the underlying Cretaceous system is one of unconformable overlap.[53] In the north part of the oasis we have the Eocene (Up. Lib.-Low. Mok.) overlying directly the lower beds of the Cenomanian; further south, on the west, the same beds overlie the White Chalk of Danian age, and no doubt at an intermediate point the Eocene overlies the intermediate beds. On the east side, though the actual demarcation of the Eocene and Cretaceous beds is a matter of some difficulty, the difference of dip between the two systems in some localities is well marked.
It seems certain then that after the deposition of the Cretaceous beds in this region, elevation took place with a considerable amount of folding (which will be noticed fully further on). The land thus formed underwent a marked denudation before subsidence took it below the surface of the sea and allowed of the deposition of the Eocene deposits just described.