EVALUATION, RADIOACTIVITY AND MECHANICAL ANALYSIS OF THE TOP METER BLACK SANDS NORTH EAST OF MOTOBAS INDUSTERIAL SECTOR, KAFR AL-SHEIKH GOVERNORATE, EGYPT.

ABSTRACTThe coastal plain of study area covered by sea water rich in fines derived from the clay lenses of the continental shelf by erosion processcomprises three zones; eastern, middle and western. So, the high content of fines variesfrom 0.72 % to 74.08 with an average of 18%.Theapparent specific gravityof topmost partof the sands one meter thick varies from 1.29 g/cm³ to 1.74 g/cm³with anaverage of 1.59 g/cm³.The studied sediments are derived fromriver environment, due to the high content of clay and organic matter in the raw sands. The average percentage of sand fraction finer than 125 micron hasanaverage value of 19.51 %,in which thetotal heavy fractions constitutes92.78 %in average of its total amounts.The calculated total reserve of the economic heavy minerals reaches up to578,760tons separated from 2893.800 tons bulk sands. Its mineralconstituents are;182,850tonsmagnetite, 329,130 tons ilmenite, 23,850 tons garnet, 14,310 tons leucoxene, 20,670 tons zircon, 6,996 tons rutile and 954 tons monazite.The radiometric measurementsof the study area revealed that the western zone which occupiesfour square kilometers have high valuesof specific activity, absorbed and effective doses because of itshigh contents of monazite and radioactive zircon, while the eastern and middle zones eachoccupythree square kilometerspossesa moderatetolow values of these activitiesrespectively.Therefore, thethe western zone isnot recommended asbuilding materialsbecause of itsrelatively high radioactivity.Meanwhile, sands of the middleand eastern zones are recommended for the same target, after separation the economic and strategic minerals of strategic importance.