Enrichment of rare earth and radioactive elements concentration in accessory phases from alkaline granite, South Sinai- Egypt

The occurrence of a unique accessory mineral association in alkaline granite of Wadi Umm Adawi-Yahmid area, South Sinai with significant enrichment of Rare earth elements (REE), Th, U and Y is described. These minerals are chevkinite, zircon, monazite, apatite and thorite. Chevkinite is recorded for the first time in this type of granite. Petrographical and textural criteria indicate that apatite, zircon and chevkinite are the early crystallized phases while thorite and monazite are the late phase. REE abundance is clearly identified in chevekinite, monazite and Apatite while; Th, U,Y are concentrated in chevkinite and zircon. The distribution of REEs, Th, U and Y in alkaline granite result from processes allowing substitution, redistribution and enrichment such processes include late or post magmatic (fractionation and alteration). Alkaline granite of the studied area and its weathering product may be considered as a potential source of REEs, Th, U and Y.