GEOLOGY, MINERALOGY AND RADIOELEMENTS POTENTIALIYY OF MICROGRANITE DIKES TO THE SOUTH OF WADI ABU HADIEDA AREA, NORTHERN EASTERN DESERT, EGYPT

Abstract

The granite dike swarms intruding the older granitiod and occasionally the younger gabbros were emplaced througha shear zone extending in NE-SW direction. These dikes are composed mainly from alkali feldspar granites. They are finegrained, hard and compact vary in color from pink, red, reddish brown and occasionally bloody red. It is affected by varyingdegrees of alterations and subjected to deformation processes. Mineral segregations and pegmatite pockets are encounteredalong deformed and altered zones. Alkali feldspars mainly perthites and microcline, quartz, little sodic plagioclaseand biotite represent the main rock forming minerals. These dikes possess high contents of radioelements especiallythorium. The eTh contents range from 63.9 ppm to 2523 ppm with an average 465.8 ppm where the eU content range from25ppm to 497.9 ppm with 106.3 ppm average. The mineral segregations give the highest level of eU and eTh contents reach upto 7331 ppm and 1386 ppm respectively. Secondary uranium minerals (uranophane and curite), thorium minerals (thorite) andU- and Th-bearing minerals (Zircon, allanite, columbite, samarskite, xenotime, monazite, kasolite and titanite) are identified.Other non radioactive minerals such as magnetite, goetite, hematite, cronstedtite, pyrite, fluorite, garnet are also identified.Also, chemical analyses (XRF) revealed presence of high concentration of U, Zr, Y, Nb, Ba, Zn, Rb and Sr in addition to presenceof V, Pb, Ni and Cr. Au and Pt are also present