"Natural radioactivity and Rare Earth elements in feldspar samples , Central Eastern desert , Egypt"

Abstract

The pegmatite bodies of the Eastern Desert of Egypt are widely distributed especially along the Marsa-Alam-Idfu road .The Abu Dob area covers about 150 km2 of the Arabian Nubian shield at the central part of the Eastern Desert of Egypt .Most of the pegmatite is zoned ;the zonation starts with milky quartz at the core followed by alkali feldspar at the margins .The feldspars vary in color from rose to milky and in composition from K- feldspar to Na- feldspar . sometimes interations of both types are encountered . Thirteen feldspar samples were collected from different locations in the Abu Dob area for measuring the natural radioactivity of 238U , 232Th and 40K using an HPGe detector .The variation in concentration of radionuclides for the area under investigation in Bqkg-1 has been observed to be from 9.5 to 183675.7 Bqkg-1 for 238U , between 6.1 and 94,314.2 for 232Th and from 0 to 7894.6 for 40K . Radium equivalent activities (Ra eq) . dose rate (DR) and external hazard(Hex) have also been determined .In the present work the concentration of rare earth elements are measured for two feldspar samples using two techniques .Environmental Scanning Electron microscope XIL 30 ESEM, Philips , and Inductively Coupied Plasma Mass Spectroscopy (ICP-MS).The existence of rare earth elements in this area are very high and can be used in different important industries.