... into the Tertiary. The Tertiary Hudi Chert, found in scattered outcrops in the region of Atbara, was considered to overlie the Nubian Sandstone Formation. We suggest that the Hudi Chert is partly age equivalent to the Tertiary upper Nubian Sandstone at Jebel Mudaha. The Nubian Sandstone Formation...

..., 1942 ; Berry and Whiteman, 1968 ; Whiteman, 1971 ). Berry and Whiteman (1968 , p. 27, Fig. 15) dated the Shendi surface, an extensive lateritic or iron-enriched surface (of which Prasad’s laterite forms part), as pre-Hudi Chert ( i.e. , pre-?Oligocene) and post-Nubian Group ( i.e. , post-?Early...

... Code ( American Comm. Stratigraphic Nomenclature, 1961 ). I have defined the Nubian Group for Sudan Republic ( Whiteman, 1969 ) as: Those conglomerates, grits, sandstones, sandy and calcareous mudstones and ironstones which are overlain unconformably by the Hudi Chert formation (Lower Tertiary...

...Fig. 3. An interpretation of present-day altitude of the ‘Shendi surface’ ( Berry & Whiteman 1968 ), and possible equivalents, including the lateritic surfaces of Schwarz & Germann (1999) , the Eocene–Oligocene facies change, the probable Oligocene Hudi Chert (occurrences from Whiteman...

... are younger than the Paleozoic, Carboniferous sandstones on which they lie locally but they more usually lie unconformably on the Basement Complex in the major part of the Sudan. The sandstones are older than the Upper Lower Tertiary (Oligocene) Hudi chert and the Tertiary plateau basalts. Locally Tertiary...

... parts of the area. The contacts between the ophiolitic rocks and the metamorphic rocks are defined by faults. The Pre- to Late Cretaceous ophiolite mélange is composed of serpentinized peridotite, gabbro, diabase and pelagic limestone with minor amounts of radiolarian chert. Serpentinized peridotites...