Журнал наук о Земле и изменения климата

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Tectono-Gravity Probing and Observations on the Rising Mantle Wedge in Central, NE and N Sudan Areas

Hussein Muhammed, Abdel Hafiz G. Mula

In the present study, two regions of the NE, N areas of Sudan have been investigated through gravity probing. A recognized number of anomalies have been observed, interpreted in the light of the plate tectonics theory models and the related structural deformation of the Wilson cycle in the western part of the Nubian-Arabian Shield. These gravity data have been acquired by many foreign and geological institutions contoured to prepare two gravity maps of the whole country, and N Sudan regions. The derived models uncover a new region with mantle up-welling and mantle wedge along the Red Sea offshore and central NE Sudan as a possible extension of S of Keraf Shear Zone, respectively, while the others have shown crustal thickening decorated by ophiolitic shear zones. High anomalies indicate a higher densityrock appraised to exist from the 3D gravity model and buried within the vicinity of Atbara and Shandi cities and are being referred to as buried ophiolitic sinusoids, low-grade metamorphic rocks of greenschist facies with tectonic mélange of a subduction zone. Their possible source according to the anomalies is surmised to be the Serpentinized - Mantle wedge of the Neoproterozoic subduction zone formed beneath the southern extension of Keraf Shear Zone, which is buried under the recent thinner and lighter geological cover in the Shendi-Atbra vicinity. A crustal thickening texture with various undulations in the Mohos’ interface has been observed from the gravity map that occurs in the lithospheric length between Nile valley and the Red Sea offshore.