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Um Taghir area located along the shear zone of the Qena-Safaga road, mostly it represents one of the most important occurrences of radioactive elements in the Central Eastern Desert of Egypt. The current study aims to calculate the content of the radioactive elements of the investigated granitic rocks by radiative methods for the geochemical parameters. Major oxides such as SiO2, Al2O3, Fe2O3, CaO, MgO, TiO2, P2O5, Na2O and K2O in addition to trace and rare earth elements (Cr, Ni, Cu, Zn, Zr, Rb, Y, Ba, Pb, Sr, Ga, V, Nb, As and Co) are measured by (X-ray fluorescence (XRF) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The average activity (range) of 238U series, 232Th series and 40K were 15.7 (8.7–25.7), 13.2 (4.7–11.7) and 703.8 (195.1–1371.8) Bq/kg, respectively. The average concentrations values of 226Ra, 232Th are lower than those of the world's average and the average activities in Egyptian soil. While in the case of potassium (40K), we find that the radioactive content is greater than the world's average, and also the radioactive average of the Egyptian soil. The scope of estimated exercises generally contrasted as their quality in rocks tests relies upon their physical, synthetic and geo-concoction properties and the appropriate condition. [ABSTRACT FROM AUTHOR]

Granite rocks are currently one of the foremost raw materials that can be used for various economic purposes such as ornamentation and building materials, because they do not possess radioactive concentrations and have good physical and mechanical properties. The granite rocks of north Um Taghir are connected to neoproterozoic rocks and integrated to the north Arabian-Nubian Shield (ANS), which lies in Northeast Africa. Inductively coupled plasma mass spectrometry (ICP-MS) and X-ray fluorescence analysis, concurrent to some statistical analysis, have been carried for major oxides and some trace elements to extract much fundamental information by following certain mathematical methods. The exposed granite rock units in north Um Taghir are classified into four rock units represented by tonalite, granodiorite, monzogranite, and alkali-feldspar granite which are cut by different types of dikes. The magma of tonalite and granodiorite is low-to-medium K calc-alkaline affinity, while the magma of monzogranite and alkali-feldspar granite is medium-to-high K calc-alkaline affinity, and of metaluminous to peraluminous nature. Granite rocks show a slightly depletion of fractionated patterns from light rare earth elements (LREEs) to heavy rare earth elements (HREEs) with slightly positive to negative Eu anomalies from tonalite to monzogranite and alkali-feldspar granites. The statistical criteria have been achieved to explore the significant differences of radiological hazard parameters among samples. It is obvious that there is no homogeneity among samples; furthermore, in Kruskal–Wallis test, Mann–Whitney test, and Pearson correlation coefficient, it can be noticed that there are significant differences between each pair of samples: tonalite, monzogranite; tonalite, alkali-feldspar granite; granodiorite, monzogranite; and granodiorite, alkali-feldspar granite. There is a strong direct relationship among granodiorite and both tonalite and alkali-feldspar granite, and among alkali-feldspar granite and tonalite and granodiorite. There is a strong inverse relationship among monzogranite and tonalite, granodiorite, and alkali-feldspar granite. As stated by all results, it can be mentioned that the granite rocks have a worthy result of mechanical and physical properties. So that they can be used for various economic purposes.

The current study presents the integration between field observations and remotely sensed data for detection and extraction of geological structural features using Sentinel-2A and Aster DEM images. The area under investigation is represented by the Neoproterozoic East African Orogeny encompassing a part of the Arabian Nubian Shield. All the rock units studied belong to the Late Cryogenian-Ediacaran periods that are divided into two large terrains (continental arc terrain and oceanic arc terrain). The metagabbro and metavolcaniclastic rocks make up the oceanic terrain, while the gabbro, tonalite, granodiorite, dokhan volcanic, monzogranite and alkali feldspar granite comprise continental arc terrain. The Sentinel-2A remote sensing and ASTER DEM data have meaningful application in respect of geological interpretation. Lineament analysis is one of the most useful tools in geological mapping and mineral exploration. Several methods of processing and extracting lithological information and lineaments were applied to the Sentinel-2A and ASTER DEM data covering the present study. The methods include various image enhancements (FCC, MNF and PCA) and the application of directional filters (Sobel). The study results show that the area was subjected to stresses of various directions (WNW – ESE, NW-SE, NE-SW, N-S, NNE – SSW, and E-W). There occurred some important structure-related and mineralization events like migmatization (in granodiorites) and bearing mineralization (in gabbro), which are associated with major elements of evidence-based structural control of the area and with the proximity of the Quena Safaga shear zone-related mineralization.