The Lower Paleozoic rock units in Egypt: An overview

Abstract

Lower Paleozoic rocks are exposed in various regions of Egypt (south central Sinai, north Eastern Desert and southwest Western Desert), in addition to occurring in the subsurface such as north Western Desert and the Gulf of Suez. The Lower Paleozoic rocks in Egypt include surface and subsurface rock units of formational status. The surface rock units are the Taba, Araba and Naqus formations. The subsurface rock units include the Shifa, Kohla and Basur formations.The Infracambrian Taba Formation has been discovered recently in the outcrops of the southeast central Sinai in the Taba-Ras El-Naqab area. It is missing and/or not recognized in the subsurface. The Taba Formation consists mainly of reddish brown, unfossiliferous gravelly fine-to medium-grained kaolinitic sandstones and subordinate horizons of paleosols. The Cambrian Araba Formation and its subsurface equivalent (the Shifa Formation) are essentially composed of reddish brown, fine-grained laminated sandstone and siltstone with abundant Skolithos and Cruziana sp. In contrast, the OrdovicianeSilurian Naqus Formation and its subsurface equivalents (the Kohla Formation and Basur Formation) are mainly composed of white, unfossiliferous, cross-bedded, medium-to coarse-grained sandstones with haphazardly distributed pebbles and cobbles. Sedimentological analysis indicates that the Araba Formation and its subsurface equivalent were deposited in a marginal-marine environment, whereas the Naqus Formation and its subsurface equivalents were laid down in a fluvio-glacial environment.Integrated stratigraphic and sedimentological studies of the Lower Paleozoic rocks permit reconstruction of the paleogeography of Egypt at that time. Egypt has been largely controlled since the Cambrian by the pre-existing structural framework of the pre-Phanerozoic basement rocks inherited from the Late Proterozoic Pan-African event. Additionally, sedimentation processes were controlled during Cambro-Ordovician times by tectonic movements, whereas glacio-eustatic control predominated during the Late OrdovicianeSilurian Period. These studies suggest that most areas of Egypt were exposed lands Production and hosting by Elsevier available at www.sciencedirect.com China University of Geosciences (Beijing) GEOSCIENCE FRONTIERS journal homepage: www.elsevier.com/locate/gsf GEOSCIENCE FRONTIERS 2(4) (2011) 491e507with episodically transgression by epi-continental seas related to the paleo-Tethys. These lands formed a part of a stable subsiding shelf at the northern Gondwana margin. ª 2011, China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B.V. All rights reserved.

Mineral Industry in Egypt– Part II Non-Metallic Commodities – Silica Ores

“…The white sand in Wadi Qena constitutes most of the lower Paleozoic Naqus Formation (450 km 2 ) North-East of Qena. The Northern part of Wadi Qena consists of the exposed lower Paleozoic rock units which are represented by Araba and Naqus Formation (Wanas 2011). The Naqus Formation rests unconformably on the peneplained Precambrian crystalline rocks of Araba-Nubian shield and form scattered outcrops in a series of hills and mesas.…”

Uranium Mineralization Hosted by the Paleozoic Sandstones at Southwest Sinai, Egypt

“…Akarish and El Gohary (2008) incorporated mineralogy and chemical composition of the lower Paleozoic sandstones in East Sinai to disclose their provenance and tectonic setting. Wanas (2011) classified the lower Paleozoic rock units in Egypt including Sinai Peninsula. This classification includes surface units (Taba, Araba and Naqus Formations) and its equivalent subsurface rock units (Shifa, Kohla and Basur Formations).…”

Cambrian ichnofossils from northeastern Egypt

“…2A-B). Cambrian to Carboniferous rocks are known from Sinai Peninsula, the Jebel Uweinat area in the southwest as well as from southern Egypt, the Eastern Desert, and subsurface in northern Egypt (klitzSch 1990a, b;giraud 1999;tawadroS 2001garfunkel 2002;wanaS 2011). Whereas Silurian (sandstone and shale), Devonian (sandstone, conglomerate, carbonate) and Carboniferous sedimentary rocks (sandstone, shale, carbonate, coal) have been securely dated by their fossil content, biostratigraphic data from Cambro-Ordovician rocks are limited (summary by tawadroS 2012).…”