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  • Essay / The basement rocks of the northeastern desert of Egypt

    The Egyptian basement complex is considered to represent part of the Arabian-Nubian Shield (ANS) or the northeastern extension of the shield nubian fig. The complex Neoproterozic basement rocks of the ANS across the Egyptian province consist mainly of gneisses, volcanic rocks and metasediments cut by granites, granodiorites and a series of dolerite dykes. They occupy the southern part of Sinai and cover a vast area of ​​the eastern desert forming the Red Sea mountain ranges, the northern tip of this mountain range beginning at approximately 28° 40' north latitude; and the range extends approximately 830 km south to Sudan, gradually increasing in width from a few kilometers to almost 400 km along the Sudanese border. Additionally, basement rocks are present and cover limited areas in the Nile Valley at Aswan, in addition to the southern part of the Western Desert at G. Uweinat. The eastern desert was divided into three provinces; North-Eastern Desert (NED), Central-Eastern Desert (CED) and South-Eastern Desert (SED). These three areas reflect the following: (1) There is a much higher concentration of granitoids in the NED and SED than in the CED; (2) Ophiolites and serpentinites are absent from the NED; (3) gneisses are most abundant in the SED; and 4) The DEC holds the largest concentration of rocks with strong oceanic affinities, such as ophiolites and the Banded Iron Formation (BIF). The study area is the Northeast Desert Province whose basement rocks are largely composed of granitic rocks with limited outcrops of high-grade gneisses, Dokhan volcanics and Hammamat sediments or their equivalents. Here the ophiolitic mixing is very limited compared to its occurrences in the central and southern parts of the Eastern Desert of Egypt. The basement rocks of the northeastern Egyptian desert have already been described and studied by many authors. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get the original essay Granite rocks constitute approximately 60% of the total Neoproterozoic outcrops of the Eastern Desert of Egypt. Their wide distribution and clear identification in the field have led many authors to classify and describe them such as El Ramly and Akaad (1960); Akaad and Noweir who classified the granitoids into gray and pink granites as well as older and younger granites. And El Gaby (1975) was the first to classify the granitic rocks of Egypt into two groups: (a) syn-orogenic granitoids, which include gray granites representing older granites and (b) post-orogenic granitoids which include pink and red granites and represent younger granites. granites, while (Akaad et al., 1979) classified the granites of Egypt into older granites (gray) and younger granites (pink). The oldest granites are mainly diorites, quartz diorites, tones and granodiorites. The youngest granites are mainly monzogranites, syenogranites and alkali feldspar granites. On the other hand, Greenberg (1981) classified granitoids according to their geological context and their petrography into three phases (Phases I, II and III). I consists mainly of granodiorites with minor monzogranites, while phase II consists mainly of monzogranites and syenogranites. Phase III is mainly made up of alkali feldspar granites. The four targeted areas can be described geologically as follows: The Ras Gharib area represents a coastal region covered with Pliocene-Recent alluvium).