title: 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 150km(2) 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 interactions of both types are encountered. Thirteen feldspar samples were collected from different locations in the Abu Dob area for measuring the natural radioactivity of (238)U, (232)Th and (40)K using an HPGe detector. The variation in concentration of radionuclides for the area under investigation can be classified into regions of high, medium and low natural radioactivity. The average concentration in BqKg(-1) has been observed to be from 9.5 to 183675.7BqKg(-1) for (238)U, between 6.1 and 94,314.2BqKg(-1) for (232)Th and from 0 to 7894.6BqKg(-1) for (40)K. Radium equivalent activities (Ra(eq)), dose rate (D(R)) and external hazard (H(ex)) 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 Coupled 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.
authors.affiliation: Department of Physics, Faculty of Girls for Art, Science and Education, Ain Shams University, Heliopolis, Cairo, Egypt. nadia_walley5@hotmail.com
authors.forename: Nadia
authors.initials: N
authors.lastname: Walley El-Dine
authors.forename: Amal
authors.initials: A
authors.lastname: El-Shershaby
authors.forename: Sofia
authors.initials: S
authors.lastname: Afifi
authors.forename: Amany
authors.initials: A
authors.lastname: Sroor
authors.forename: Eman
authors.initials: E
authors.lastname: Samir
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D003889:Desert Climate; D004534:Egypt; D008674:Metals, Rare Earth / Q000032:analysis*; D017680:Potassium Compounds / Q000737:chemistry*; D011851:Radioactivity
chemical_list: D000538:Aluminum Silicates; D008674:Metals, Rare Earth; D017680:Potassium Compounds; C016447:feldspar