Abstract
The Arabian shield, in the western part of Saudi Arabia has significant iron and copper ore deposits, they have promising economic potential with their reserves. Nine rock samples were collected from different areas of it and prepared for analysis. XRD was applied to determine the mineral composition of the samples, which revealed that the major minerals are QUARTZ (mostly in all samples), MAGNETITE, HEMATITE, CORUNDUM, GOETHITE, MONTMORILLONITE, PYRITE, ANKERITE, BOEHMITE, SPINEL and ALBITE, with additional minor and trace minerals. Samples were analyzed for concentrations of, U-238, Th-232, and K-40 by the gamma spectrometer based on hyper pure germanium detector "HPGe" crystal. For U-238 concentrations, the values in Bq/kg dry weight ranged from 152.68 to 264.73 (for iron ore), 156.37 and 329.98 (for copper ore). For Ra-226, the activities of Pb-214 and Bi-214 in equilibrium with parent (Ra-226) were used to calculate the concentrations in Bq/kg dry weight, the average values ranged from 2.50 to 386.30 (for iron ore), 57.41 and 1048.01(for copper ore). While the activities of Th-232 series were calculated from daughters Ac-228, Bi-212, and Tl-208, the average concentrations in Bq/kg dry weight ranged from 1.50 to 183.90 (for iron ore), 43.66 and 44.41(for copper ore). K-40 concentration values in Bq/kg dry weight ranged from 2.70 to 186.99 (for iron ore), 48.92 and 191.33 (for copper ore), and the U-238 concentrations in Bq/kg dry weight ranged from 8.35 to 13.70 (for iron ore), ND and 18.37 (for copper ore). the Ra-eq Bq/kg dry weight which ranged from 10.88 to 333.59(for samples 1,2,3, 6,7,9), they are less than 370 the permissible value adopted by EPA and UNSCEAR (2000), while for samples 4, 5 were 610.63 and 662.56 which they are higher than the value 370, for sample 8 (Jabal Sayid) has the highest value 1114.21 (Bq/kg). [Safia H. Q. Hamidalddin and Afaf A. Fakeha. Natural Radioactivity Levels in Environmental Samples (Iron and Copper) in the Arabian Shield, the Western Part of Saudi Arabia. Life Sci J 2012;9(4):1605-1610] (ISSN:1097-8135). http://www.lifesciencesite.com. 245