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Geology of the Sudan
Published in J.R. Vail, Lexicon of Geological Terms for the Sudan, 2022
There were two major differences during the Tertiary and Quaternary from the earlier Mesozoic era. The Arabian-Nubian Shield split along the Red Sea rift and with the incursion of the sea marine deposits accumulated along the coast. At the same time eruptions associated with within-plate volcanism and with the East African Rift System increased and significant volcanic fields of mainly basaltic lavas accumulated. Deposition continued in the north and in the deepening rift basins occupied by the present day White Nile and Bahr El Arab rivers, and the Blue Nile River developed a large delta across the present Blue Nile and Gezira Provinces. Towards the end of the era climatic conditions fluctuated between moist and dry and progressively the wind blown sands and fine alluvial silts accumulated to cover much of the present surface of the country.
Magmatism in the Context of the Present-Day Tectonic Settings
Published in O.A. Bogatikov, R.F. Fursenko, G.V. Lazareva, E.A. Miloradovskaya, A. Ya, R.E. Sorkina, Magmatism and Geodynamics Terrestrial Magmatism Throughout the Earth’s History, 2020
O.A. Bogatikov, V.I. Kovalenko, E.V. Sharkov, V.V. Yarmolyuk
A similar sequence of magmatic evolution is found during the formation of back-arc basins, for example the Japan Sea (Tamaki, 1988; Frolova et al., 1989). Its development began about 30 Ma ago, in the form of a continental-margin rift in the rear part of the newly formed active margin of Eurasia (Amur microplate). As in the case of the Red Sea Rift, subaerial K–Na moderately alkaline basalts and ignimbrites (“green tuffs”) were the predominant rocks. The relics of this continental crust were preserved beneath submarine rises such as the Yamato, Oki and Korean rises. The submergence of the region was accompanied by extension, starting in the early Miocene and intensifying during the middle and late Miocene, with the formation of a marine basin and the eruption of tholeiitic basalts, including MORB, and generation of oceanic crust took place in the newly formed deep-sea basins, for example in the Yamato Basin. Thus, the evolution of deep-seated melts, from Fe–Ti moderately alkaline to tholeiite with the generation of MORB in the more developed regions, takes place by the opening of both new oceans and back-arc basins. This tendency is exhibited on some large oceanic islands, for example in the early stages of the development of Hawaii, although MORB have not been generated there. This type of evolution could be attributed to melting of the ultrabasic substrate of upper-mantle asthenospheric plumes; the general evolution trend is towards oceanization of the crust.
2 emissions reduction and climate mitigation
Published in Heping Xie, Jian Zhao, Pathegama Gamage Ranjith, Deep Rock Mechanics: From Research to Engineering, 2018
D. Chandrasekharam, K. Bankher, P.G. Ranjith
The Arabian shield has undergone several stages of deformation and stresses since it breakup from the Nubian Shield (Hamimi et al., 2013). The shield has undergone initial three regional deformation (D1, D2 and D3) that are printed over these granites and granite gneisses (Hamimi et al., 2013). The initial D1 deformation resulted due to E-W shortening of the shield followed by D2 deformation resulted due to W-WSW thrust. Due to the rotation of the shield anti-clock wise, the D3 deformation changed from E_W to NE-SW. With the opening of the Red Sea the current extension is perpendicular to the Red Sea axis (NNW-SSE) (Fig. 5). This stress pattern will continue as long as the Red Sea rift is active due to volcanic activity along the Red Ridge axis.
Hydrogeophysical characterization of the Southern Red Sea coastal aquifer, Saudi Arabia, using Time-Domain electromagnetic method
Published in Human and Ecological Risk Assessment: An International Journal, 2023
Salman S. Alharbi, Saleh I. Qaysi, Mahmoud M. Elwaheidi
The geological setting of the area is highly affected by the opening of the Red Sea tectonics that began in the late Oligocene and is still active today (Bosworth 2015). The Arabian Shield was a part of the Arabian-Nubian Shield before the divergence occurred between the Arabian Plate and the African plate forming the Red Sea rift. The evolution of the Red Sea basin has resulted in the accumulation of salts along the coastal area and formed sabkha areas that are dominated by the presence of halite and gypsum (Nehlig et al. 2002). The surface geology of south Jazan (Figure 1b) is mainly composed of the igneous and metamorphic rocks of the Proterozoic basement in the eastern part, which is separated from Quaternary sediments and Quaternary-Tertiary carbonates along the Red Sea coastal plain by an escarpment. The Quaternary sediments contain alternating layers of sand and gravel that originated by the erosion of basement rocks (Fairer 1983; Camp and Roobol 1989; Zaidi et al. 2017).