دراسات تركيبية وإشعاعية لمنطقة أم جروف، شمال الصحراء الشرقية، مصر

Abstract

The present work deals with the geology, structure and radioactivity of Um Guruf area, North Eastern Desert, Egypt. Um Guruf area is bounded by latitudes 27º 06΄ 35˝ and 27º 15΄ 40˝ N and longitudes 33º 00΄ 18˝ and 33º 10΄ 25˝ E covering an area of about 275 km2. The study area is mainly covered by Neoproterozoic basement rocks. Based on field and petrological studies, the main rock types cropping out in the study area can be chronologically arranged from oldest to youngest as: older granitoids, Dokhan volcanics, Hammamat sedimentary rocks, younger granites and post granite dykes. Older granitoids in the study area are mainly represented by granodiorite, which is exposed in the southern parts of the mapped area with very small exposures around G. El Resha and G. Al Hamra alkali feldspar granites. Granodiorite occurs as rounded to sub rounded low to moderate small separated hills with gentle slopes. It is medium to coarse grained with grey colour. It is intruded by younger granites and dykes trending NE-SW. In some parts, it is highly fractured and exfoliated.