GEOLOGY AND RADIOELEMENTS DISTRIBUTION IN GABAL SALAAT EL BALI AND GABAL EL REDDAB ENVIRONS, NORTH EASTERN DESERT, EGYPT

Abstract

Gabal Salaat El Bali and Gabal El Reddah environs are located in the northern part of the Eastern Desert of Egypt between longitudes 33° 18.' 06 11 - 33° 25.1 3811 E and

latitudes 27° 051 !011 - 27° 13 1 1111 N. The area, about 200 km 2

is occupied by late

Proterozoic basement rocks including various types of granites, Hamarnmat sedimentary rocks and Dokhan volcanics.

The examined granitic rocks comprises the two well-known granite groups in

Egypt namely the "Older granites" and the "Younger granites" (El Ramly and Akaad,

1960). The Older "gray" granites are represented mainly by quartz diorite. The Younger Granites include Salaat El Bali composite pluton (biotite-hornblende monzogranite and biotite-hornblende syenogranite), El Reddah pluton (biotite monzogranite), Urn Nafie pluton (biotite syenogranite) and Qattar pluton (syenogranite to alkali feldspar granite). The area is dissected later by Katharina subvolcanic alkali granite and post-granite dykes. The gray granites are unconformably overlain by the Hamammat sedimentary rocks and are intruded with sharp intrusive contacts by the Younger granites.